review & contact lenses

Tear Film Dynamics • Scleral-induced Pingueculitis • Breaking Bad Habits • Building Your Practice

Supplement to

TARGETING

Astigmatism

EARN 1 CE CREDITEARN 1 CE CREDIT

The Toric

Toolbox P. 08

Taking Torics

to the Top P. 10

Sclerals for Irregular

Corneas P. 14

Surgical Correction of

Astigmatism P. 18

NOVEMBER 2016

RCCLRCCLREVIEW OF CORNEA & CONTACT LENSES

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* Among patients who use digital devices at least 4 hours per day at least 5 days per week and self-report symptoms of eye fatigue at least once per week.

1 After 1 week of wear; data on file.

2 The Vision Council. Eyes overexposed: the digital device dilemma: 2016 digital eye strain report.

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Review of Cornea & Contact Lenses | November 2016

departments features

contents

18CE — Surgical Options for the Correction of Astigmatism

Today’s sophisticated surgical tools and techniques off er dramatically improved outcomes over the imprecise early eff orts of yesterday.

By Kristen Brown, OD

News Review4Corneal Thickness May Help Predict

CXL Outcomes; New Stats Highlight

the Need for More DED Education

My Perspective 6A Look at the Androgen Connection

By Joseph P. Shovlin, OD

10Taking Torics to the TopFitting toric lenses has become increasingly straightforward and now presents a viable option for myriad contact lens wearers.By David Kading, OD, and

Charissa Young, OD

14

29

24

When to Opt for

Scleral Lenses Irregular cornea patients in particular can enjoy the many benefi ts that accompany fi tting scleral lenses.By Michael J. Lipson, OD

Advances in Understanding Tear Film DynamicsLet’s gain some perspective on the components, modalities, and methodology of dry eye.By Will Smith, OD

Case Report: Solving Scleral Contact Lens-Induced PingueculitisThe simplest option is often the best solution.By Brian Chou, OD

Breaking Habits

By Mile Brujic, OD, andJason R. Miller, OD, MBA

Practice Progress32

The Toric Toolbox: Don’t Forget GPs

By Robert Ensley, OD, andHeidi Miller, OD

The GP Experts8

Four Keys to Building Your Practice

By Gary Gerber, OD

Out of the Box34

4 REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016

News Review

Corneal Thickness May Help

Predict CXL Outcomes

IN BRIEF

■ Dry eye symptoms and body fat may be correlated, a new prospective study suggests. Researchers sampled ocular symptoms and indices of adiposity in the general adult population and in the 305 participants, including 53 contact lens wearers. Results show a moderate cor-relation between body fat percentage and dry eye symptoms. Chronic infl am-mation may be the link. “Adipose tissue contributes to a rise in circulating levels of many proinfl ammatory mediators,” the researchers state.Ho KC, Jalbert I, Watt K, Golebiowski B. A possible association between dry eye symptoms and body fat: a prospective, cross-sectional pre-liminary study. Eye & Contact Lens. 2016. EPub ahead of print.

■ Keratitis infections appear to be more common in the summer, according to a new study. Researchers performed a retrospective chart review on patients presenting to the emergency department who were diagnosed with infectious keratitis from 2008 to 2013. Looking at data from 155 patients diagnosed with keratitis, researchers found that 12.3% of patients with ulcers presented in the fall, 21.3% in the spring, 21.9% in the winter and 44.5% in the summer—indicating a higher frequency of infectious keratitis and P. aeruginosa positivity during the summer months. Researchers posit that possible factors for this include warmer temperatures, higher levels of humidity and increased ocular exposure to water. Gorski M, Genis A, Yushvayev S, et al. Seasonal variation in the presentation of infectious kerati-tis. Eye & Contact Lens. 2016 Sep;(42(5):295-7.

■ Researchers recently developed and evaluated a new meibomian gland dys-function (MGD)-specifi c questionnaire based on accepted tests such as the Schein symptom survey, tear break-up time, corneal and conjunctival staining, abnormal meibum or meibomian gland atrophy and a normal Schirmer test. The MGD questionnaire initially contained 24 items targeting the intensity and fre-quency of 12 symptoms. Using data from the 69 MGD subjects who completed the survey and clinical testing, research-ers worked through three iterations of analysis of subject responses to the tests. The fi nal questionnaire included seven question pairs. Researchers conclude that the study is a valid and quantitative mea-sure of symptoms common for patients with MGD. They acknowledge that further research is needed to determine whether the diagnostic effi cacy is an adequate means of diff erentiating MGD dry eye subtypes in an independent sample of normal subjects. Paugh JR, Kwan J, Christensen M, et al. Develop-ment of a meibomian gland dysfuntion—specifi c symptom questionnaire. Eye & Contact Lens.

Researchers recently exam-ined how preoperative characteristics impact the outcomes of corneal

collagen crosslinking (CXL) in pe-diatric patients and found that the thinnest baseline corneal thickness impacts the success rate of CXL after two-year follow up.1

“Keratoconus has potentially devastating effects on our patients’ quality of life,” says Barry Eiden, OD, co-founder and president of the International Keratoconus Academy. “Younger individuals (<18) who develop keratoconus have been shown to progress faster and develop more advanced disease with a higher rate requiring corneal transplantation.”

Research shows that collagen crosslinking can slow down or halt the progression of the degenerative disorder and, when successful, CXL may stabilize keratoconus while leading to a permanent fl at-tening of the cornea—a result that potentially saves individuals from progressive vision loss or risky corneal transplants in the future. This study help to further identify the particular characteristics of patients who will more likely be successful candidates for this lead-ing-edge procedure.

The study included 72 eyes of 52 patients with keratoconus. The subjects were all under the age of 18 with a two-year follow up after CXL. Researchers analyzed subgroups determined by age, sex, baseline uncorrected and corrected distance visual acuities (UCVA, CDVA), topographic cone location (central and paracentral), max-imum keratometry (k-max) and

corneal thickness at the thinnest point (thCT).

Results of the study show that two years after CXL, the mean UCVA improved considerably, while the mean thCT decreased signifi cantly in all patients. The k-max in patients with paracen-tral cones and/or a thCT of less than 450µm was more likely to progress. The other characteristics did not present any notable effect on the progression of CXL after treatment.

“The challenge,” says Dr. Eiden, “is for us to develop metrics that reliably indicate keratoconus stability vs. progression. In this study, progression was defi ned as a steepening of the maximum anterior corneal curvature value (>1D) within 3mm of the apex of the cone (k-max). Other studies suggest alternative measures that may be more reliable indicators.”2

While the effi cacy and safety of CXL in pediatric and adult patients have been thoroughly demonstrated, this study sheds light on factors that help predict successful outcomes for pediatric patients undergoing crosslinking. “Further research surely is need-ed,” suggests Dr. Eiden. “However, the take-home message continues to be the importance of early diag-nosis of keratoconus and imple-mentation of treatment methods to hopefully halt the progression of the disease prior to its signifi cant impact on visual function.”

1. Sarac O, Caglayan M, Cakmak HB, Cagil N. Factors infl uencing progression of keratoconus 2 years after corneal collagen cross-linking in pediatric patients. Cornea. 2016. EPub ahead of print.2. Duncan JK, Belin MW, Borgstrom M. Assessing progression of keratoconus: novel tomographic deter-minants. Eye and Vision. 2016 Mar;3(6).

REVIEW OF CORNEA & CONTACT LENSES | NOVEMBER 2016 5

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EDITORIAL REVIEW BOARD

Mark B. Abelson, MD

James V. Aquavella, MD

Edward S. Bennett, OD

Aaron Bronner, OD

Brian Chou, OD

Kenneth Daniels, OD

S. Barry Eiden, OD

Desmond Fonn, Dip Optom M Optom

Gary Gerber, OD

Robert M. Grohe, OD

Susan Gromacki, OD

Patricia Keech, OD

Bruce Koffler, MD

Pete Kollbaum, OD, PhD

Jeffrey Charles Krohn, OD

Kenneth A. Lebow, OD

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Kirk Smick, OD

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Loretta B. Szczotka, OD

Michael A. Ward, FCLSA

Barry M. Weiner, OD

Barry Weissman, OD

RCCLRCCLREVIEW OF CORNEA & CONTACT LENSES

Nearly 90% of eye care providers (ECPs) believe there is no representative type of dry eye disease

(DED) patient, according to the National Eye C.A.R.E. (Current Attitudes Related to Eye Health) Survey. The online survey included more than 1,000 optometrists and ophthalmologists, as well as more than 1,200 adults who had been diagnosed with DED or experienced dry eye symptoms and used artifi cial tears within the past month. Results provide new statistics on many aspects of dry eye care, including:

Patient demographics• 76% said they see more pa-

tients aged 18 to 34 with DED symptoms than 10 years ago.

• 89% of ECPs believe DED is on the rise due to multi-screen digital device use.

Screening• 94% said DED screening

should be part of the compre-hensive eye exam.

• 75% believe it’s necessary to screen for dry eye symptoms in all patients regardless of age, gender or lifestyle.

• 88% deem it important to screen women over 50.

Symptoms• 79% of patients said their DED

symptoms are currently under control.

• 52% said their symptoms are getting worse over time.

• 75% said dry eye impacts their digital device use and 64% said it impedes daily activities.

• 54% said DED symptoms im-pact their ability to work.

• 69% believe dry eye is some-thing they have to live with.

The survey also revealed the need for more patient education, noting that 72% of ECPs said most patients aren’t familiar with DED. Patient responses are in accord with this fi nding, as 25% said they didn’t realize eye dryness is a symptom of a disease, and 32% said they didn’t know DED could cause long-term damage to their eyes.

Despite the well-known need for dry eye care, 72% of patients who participated in the survey said they initiated the DED conversation themselves. More telling, 45% of patients said they did not feel it was worth mentioning dry eye because the ECP did not ask about it.

Armed with these new statistics, ECPs are better equipped to

address dry eye in every exam and help more patients fi nd the relief they never knew they needed. RCCL

Shire Pharmaceuticals. The National Eye C.A.R.E. (Current Attitudes Related to Eye Health) Survey. September 2016. Available at www.myeyelove-ecp.com/dry-eye-info-from-peers. Accessed October 19, 2016.

New Stats Highlight the Need

for More DED Education

Advertiser Index

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Dry eye is on the rise, according to

a new study, and prolonged digital

device use might be to blame.

Photo: P

aul M. K

arpecki, OD

By Joseph P. Shovlin, OD

My Perspective


A Look at the Androgen ConnectionCould hormonal therapy work for dry eye?

The elaborate tear fi lm ecosystem has to maintain its own delicate balance, de-spite infl uences from

many outside sources and intrinsic characteristics. Dry eye is one such condition to disrupt the balance, giving rise to its newer moniker, dysfunctional tear fi lm. It likely results from a host of factors, including hormone imbalance.

BENEFITS AND RISKS

Androgen has been shown to regu-late meibomian gland function, and any dysregulation has a profoundly adverse effect. Along with micro-bial invasion and duct stenosis, androgen dysregulation promotes infl ammation in meibomian gland dysfunction (MGD), ultimately affecting the tear fi lm.1 Androgens also play a similar role in lacrimal gland function.2

A defi ciency in androgen result-ing from attenuation in androgen synthesis has been documented in Sjögren’s syndrome, menopause, aging, men taking androgen blockers and in complete androgen insensitivity syndrome.2

Multiple genes coding for andro-gen activity are present in ocular tissues, and research suggests andro-gen levels are depleted in individuals with signifi cant MGD.1,3

Testosterone is the most common form of androgen. Dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEAS) and androstenedione are also referred to as androgens, though they are actually converted to testosterone and could therefore be called pre-androgens.4,5

Sex hormone defi ciency also plays a key role in most dry eye disease, and studies have analyzed various methods for delivering androgen to the ocular surface.4 Unfortunately, investigators found topical testoster-one has poor solubility and results in considerable discomfort and irritation. A transdermal orphan preparation was licensed to arGen-tis Pharmaceuticals, which yielded good results, as did a progesterone transdermal delivery option.3 No testosterone or progesterone prepa-rations have yet made it to market.

In addition to establishing effi ca-cy, a major impediment for approval is safety. Commercial testosterone’s use is limited by cost, inconvenience, discomfort and occasional side ef-fects—especially in women.3 Various reports show potential side effects for men with prostate disease and women with breast cancer (or those at high risk for each disease) when using hormone therapy. Although some theorize hormone supple-mentation enhances cancer growth, others reject this notion and show no association with increased risk.3

Regardless, a careful patient history is vital before initiating hormone therapy and, in men, a PSA blood draw and urologic exam is prudent.

Many of the side effects and safety concerns stem from oral formulations or are secondary to in-creased aromatase activity, elevated estradiol and its effect at the estro-gen receptor. Aromatase activity increases with age, obesity, alcohol intake, insulin resistance, breast cancer, medications, processed diet and sedentary lifestyle.4 Although often overlooked in clinical studies, monitoring aromatase activity and

symptoms of elevated estradiol is critical to the safe use of testoster-one in both sexes.

One alternative is a transdermal preparation of testosterone (3% to 10%) used once or twice daily. In addition, practitioners have used topical DHEA (.03% to 0.5%), the metabolic precursor to testosterone, from a compounding pharma-cy with some reported success.3

However, results have been inconsis-tent, with reports of irritation.

PLAY IT SAFE

The signifi cance of androgen for dry eye therapy is well established, and some of us will occasionally use it in a transdermal form, mostly with female patients. However, we await additional evidence to ensure mean-ingful benefi t with no harm when prescribing it to more patients. Further, we need a safe and effective commercial product to provide a remedy for dry eye. Although this has been part of the discourse for nearly two decades, a dearth of studies and clinical trials remains. Some practitioners will continue to use the off-label transdermal testosterone as echelon therapy, but it’s vital that this be accompanied by close monitoring for any evidence of hormonally responsive tumors. RCCL

1. Sullivan DA, Sullivan BD, Evans JE, et al. Meibo-mian gland dysfunction and evaporative dry eye. Ann NY Acad Sci. 2002 June;966:211-2.2. Sullivan DA, Yamagami H, Liu M, et al Sex steroids, the meibomian gland and evaporative dry eye. Adv Exp Med Bio. 2002;506:389-99.3. Dawson TL. Testosterone eye drops: A novel treatment for dry eye disease. Ophthalmol Times. 2015 Nov.4. Glaser R, Dimitrakakis C. Testosterone therapy in women: Myths and misconceptions. Maturitas. 2013;74(3):230-4.5. Olson MC, Korb DR, Greiner JV. Evaluation of warm compress therapy for meibomian gland dysfunction. Invest Ophthalmol Vis Sci. 2003 May;44:2452.

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By Robert Ensley, OD, and Heidi Miller, OD

The GP Experts

Patients often report hav-ing been told they can’t wear contact lenses because of their astig-matism. With advance-

ments in contact lens technology, however, this is no longer the case. Major soft lens manufacturers and custom soft lens laboratories now offer extended parameter ranges, allowing even the most highly astigmatic patients to fall within a correctable range.

Despite advances in soft lens technology, however, the gold standard for quality of vision is still a gas permeable (GP) lens. Research shows GP lenses provide superior vision over their soft toric lens counterparts—including for patients with moderate to high astigmatism of 2.50D or greater.1

Although fi tting GP lenses for astigmatism may seem intimidat-ing, it’s essential knowledge for contact lens practitioners.

WHEN TO USE A TORIC GP

The normal astigmatic cornea has two principal meridians 90 de-grees apart, each with a different curvature and resultant refractive power. In combination with the tear layer underneath, a GP lens provides a spherical refracting surface to correct the astigmatism. To provide optimal comfort and vision, a GP lens should center well over the visual axis and align closely to the corneal shape.

Typically, you can successfully fi t a spherical GP lens on a cornea with 2.0D or less of toricity. Before placing a spherical GP lens on the eye, you should calculate

residual internal astigmatism, which originates from the posterior cornea and/or crystalline lens. The calculated residual astigma-tism (CRA) is the difference between the total refractive astigmatism at the corneal plane and the anterior corneal astigmatism measured by ker-atometry. You can fi nd actual residual astigmatism (ARA) by subjective spherocylindrical overrefraction. The ARA is typically less than the CRA, and simple math will save chair time and frustration, as 0.75D or more of ARA can result in decreased vision.2

In this situation, if a GP lens is still indicated or preferred by the patient over a soft toric lens, you can fi t a front surface toric (FST) GP lens. FST GP lenses apply the astigmatic power on the front surface, using prism ballasting and truncation to stabilize rotation. Similar to soft toric lenses, FST GPs may require rotational com-pensation using the left add, right subtract (LARS) principle.

As the corneal astigmatism increases, you should pay greater attention to the alignment of the GP lens to the corneal curvature. Placing a GP lens with a spherical back surface on a highly astigmat-ic cornea will create a dumbbell shaped sodium fl uorescein pattern

with apical bearing along the fl at meridian, as well as pooling and edge lift along the steep meridi-an. This misalignment can cause several complications, including lens rocking or fl exure; decentra-tion; corneal molding and distor-tion; and corneal desiccation from excessive edge lift.

Although there is debate among practitioners, 2.50D or more of corneal astigmatism is a common-ly accepted threshold for using back surface toricity.3 By using two base curves (BC), one for each principal meridian, back surface toricity provides a better lens-to-cornea fi t. While several meth-ods to determine BCs exist, the Mandell-Moore guide is a popular and effi cient method. Using this fi t factor, the BC is 0.25D fl atter than the fl at meridian and 0.50D to 0.75D fl atter than the steep me-ridian, depending on the amount of corneal astigmatism. The lens

To bolster confi dence, let’s review the basics of toric GP fi tting.

The Toric Toolbox: Don’t Forget GPs

This 3.0D with the rule cornea is a great candidate for

a GP lens with back surface toricity.


power on each meridian is then determined, using the SAM-FAP principle to account for the tear lens power.

BITORIC LENSES

Because of differences in the refractive index of the contact lens and the tear lens, a GP lens with back surface toricity will induce astigmatism of approximately half the magnitude of the back surface toricity. In most cases, to correct this induced astigmatism, you can add additional astigmatic power to the front surface of the lens, making the lens bitoric.

Bitoric lenses are classifi ed into two designs: spherical power effect (SPE) and cylindrical power effect (CPE). When adding astig-matic power to the front surface of the lens, you must take rotation of the lens into consideration. SPE lenses correct astigmatism similar to a spherical lens, despite hav-ing bitoric curves. Thus, the lens power is equivalent to a spherical lens and can rotate freely on the eye without impacting vision. CPE lenses must be rotationally stable to avoid inducing further astigmatism.

To determine the bitoric design, you should compare both the di-optric BC difference and the back vertex power difference between the two principle meridians. If the dioptric differences between me-ridians are equal for both BC and back vertex power, the bitoric is an SPE design. When the dioptric differences are unequal, the lens is a CPE design—typically occurring when refractive astigmatism is

unequal to corneal astigmatism. If the back vertex power is 1.5

times the back surface toricity, the induced astigmatism effec-tively cancels out the residual astigmatism. In these cases, the front surface of the GP can be made spherical, resulting in a back surface toric only lens. While this concept may be confusing, most laboratories will determine the necessity for you.

TORIC GP FITTING

MADE EASY

Before the days of empirical ordering, diagnostic fi tting was performed with standard SPE fi tting sets and overrefraction cal-culations. Now, you can design a toric GP lens with a high degree of accuracy using only keratometry readings and manifest refraction.1

You can provide this data directly to your GP lab of choice; however, if you prefer to calculate the math yourself, the GP Lens Institute (www.gpli.info) has several guides available, including a Mandell-Moore worksheet. Additionally, there is a GP toric calculator, which provides suggested lens parameters and indicates whether the lens is an SPE or CPE design. These resources can help improve your toric fi tting confi dence. RCCL

1. Michaud L, Barriault C, Dionne A, Karwatsky P. Empirical fi tting of soft or rigid gas-permeable contact lenses for the correction of moderate to severe refractive astigmatism: A comparative study. Optometry. 2009 Jul;80:375-83.2. Sarver MD. A study of residual astigmatism. Am J Optom. 1969;46(8):578-82.3. Bennett ES, Layfi eld KA, Lam D, Henry VA. Correction of astigmatism. In: Bennett ES, Henry VA, eds. Clinical Manual of Contact Lenses. 4th Ed. Philadelphia: Lippincott, Williams & Wilkins; 2014:344-94.

The GPLI Toric Calculator, available at www.gpli.info/lens-calculator, can help you select the correct lens parameters and either an SPE or CPE design.

Example 2: CPE Spectacle Rx: +1.00-4.50x180Ks: 42.00/45.50

BC: 42.00/44.75 BVP: +1.00/-2.50ΔBC (2.75 D) ≠ ΔBVP (3.50 D)

Example 3: BST Spectacle Rx: plano-4.50x180Ks: 41.00/44.00

BC: 41.00/43.25 BVP: 0.00/-3.50ΔBC (2.25 D) x 1.5 ≈ Δ BVP (3.50 D)

The GPLI Toric Calculator

BC: 42.00/44.25 BVP: -1.00/-3.25ΔBC (2.25 D) = ΔBVP (2.25 D)

Example 1: SPE Spectacle Rx: -1.00-3.25x180Ks: 42.00/45.00


Until recently, toric lenses made up a fraction of contact lens prescriptions. Over the last couple

of years, however, toric lens use has grown substantially—now making up 13% of our total lens fi ts.1 For most eye care practi-tioners, toric contact lens patients often seem more demanding than spherical patients due to the ex-tra time and effort that goes into fi tting them. Fortunately, new lens types and modalities are sim-plifying the process and making these patients happier than ever, without much added chair time.

Twenty years ago, nearly every toric lens had to be custom ordered, and patients had to wait in our reception area for 20 minutes while the lens settled. Today, toric fi tting sets allow for instant dispensing, and the lenses settle within minutes. With much advancement in this area, we have far fewer hurdles and can offer a higher standard of care to our patients. We live in a culture marked by instant gratifi cation, which often presents diffi culties when dealing with issues that can’t be immediately remedied. Fortunately, performing contact lens fi ttings from trial sets allows us to deliver care in mere minutes for the majority of our patients.

In our practice, we still have patients with low degrees of astigmatism explain that past practitioners would not fi t them

with lenses because of their astigmatism. This is no longer the case, and it is our responsibility to show our patients the increas-ingly wide range of options they have—whether they’re astigmatic or not. Our toolboxes and lens options are ever increasing and—luckily for the less patient among us—the majority of these lenses take only minutes to fi t.

TORICITY PATTERNS

We are all familiar with astig-matism, but even within each subtype certain measures require a better understanding, as they impact how a patient sees out of their lenses. For example, it is im-portant to distinguish the differ-ences between limbus-to-limbus and central corneal astigmatism. Topography is essential to under-standing these distinctions, as re-search shows signifi cant changes occur in the shape of the cornea in the periphery, thus making conical sections (like with manual keratometry or autorefractor Ks) inadequate to predict the extent of corneal astigmatism.2 If a pa-tient has a small pupil and central astigmatism during the refraction but a large pupil in her normal environment, her true amount of revealed astigmatism may vary.

This aspect of astigmatism management is also important for correctly fi tting patients with gas permeable (GP) lenses. Patients with central corneal astigmatism, even with high power (>2.00D),

may do very well with a spher-ical lens because the lens fi ts in the peripheral cornea in a more spherical nature. When patients have limbus-to-limbus astigma-tism, on the other hand, they may reveal only -2.00D in the refrac-tion but need a toric GP lens at the landing point of the lens (Figures 1a and b).

Other notable corneal shape features worth considering are those that are neither regular nor irregular in pattern. These patients may present with vari-able refractive axis with a mini-mally variable end point during the refraction. On topography, astigmatism in such patients may appear more like a distorted bow tie rather than a classic bow tie with-the-rule (WTR) or against-the-rule (ATR). These toric pa-tients may benefi t from a custom lens that can mask or vault the corneal shape.

Astigmatism in patients with a history of injury, surgery or

ABOUT THE AUTHORS

Dr. Young is an associate at

Specialty Eyecare Group in

Seattle, WA. She specializes

in dry eye and contact

lenses. She graduated

with honors from Pacifi c

University and received the

AOF award of Excellence in

Contact Lens Patient Care.

Dr. Kading owns Specialty

Eyecare Group, a Seattle-

based practice with multiple

locations. He specializes in

anterior segment disease

and custom contact lens

fi tting.

Taking Torics to theFitting toric lenses has become increasingly straightforward and now presents a viable option for myriad contact lens wearers.

T P


disease can vary widely—ranging from normal to irregular. Rather than suggesting they all need a custom lens, we refer back to the refraction and corneal shape (see “Case Report: Custom vs. Convenience,” p. 12).

Although some patients may present with alarming fi ndings on topography, they may have a rel-atively clean refraction and min-imal aberrations. These patients may be suited for a standard soft lens (sphere or toric) rather than a custom lens, which might offer only a slight improvement over the standard lens. Of course, if a patient has a corneal alteration that would deem standard soft lenses impossible, custom lenses (GP sphere, GP toric, scleral or custom soft) must be employed.

FITTING PROTOCOL

Every lens manufacturer has its own contact lens fi tting guides, which tend to be accurate and worthwhile. Still, every practice should have a fi tting protocol in place to maximize their success with any toric lens design:2

1. For patients under 40, we al-ways round up the sphere. Most trial toric lenses on the market only come in -0.50D. For exam-ple, we round the spherical pow-er up to -1.50D in a patient with a prescription of -1.25-1.00x175.

2. When working with a pa-tient with cylinder power that is between the options, we round down. Because soft contact lenses rotate about six degrees on average, rounding down minimizes visual distortions.3

As an example, we round the cylinder power down to -0.75D for a patient with a prescription of -1.25-1.00x175. Generally, if the sphere power is between stock powers and the cylinder power is between lens options, our practice is to round up with the sphere and down with the cylinder so that the spherical equivalent equals itself out.

3. For an axis that does not nail itself directly or clearly towards one, we round towards 180 for WTR and 90 for ATR. For a patient with a prescription of -1.25-1.00x175, we round the axis to 180 (Figure 2).

For patients with presbyopia, we may elect to round down for the spherical component, but maintain the other two protocols.

By David Kading, OD, and Charissa Young, OD

Figs 1a. and 1b. Topography is essential for understanding distinctions in corneal shape that aff ect GP lens fi tting.

Patients with apical astigmatism (left) often do well with spherical lenses, while those with limbal astigmatism (right)

often need a toric GP lens.


MAINTENANCE AND

PRESCRIPTION GUIDELINES

Lens comfort is paramount for success in fi tting toric lenses. Addressing and treating dry eye will decrease chances of eye rubbing, which can induce lens rotation and decrease vision quality. Unless the patient has a parameter that is not available in a daily disposable modality, we recommend dailies to provide the most comfortable contact lens wearing experience.

Toric single-use lenses are available from every major contact lens manufacturer. There now exist single-use silicone hydrogel lenses as well, which maintain the high oxygen per-meability found in two-week or monthly lenses.

Although fi tting most patients with toric powers is simpler and more direct than ever before, practitioners should always apply a greater degree of scrutiny for patients who have kerato-

conus or surgically altered eyes. These irregularities can account for signifi cantly different needs and outcomes, typically requiring customized lenses to maintain corneal health and maximize visual outcomes. Most common-ly, however, we fi nd toric lenses provide much of what an aver-age patient seeks. As a result of advancements in toric lenses over the last few years, we recom-mend and fi t for toric single-use lenses far more often than ever before.

Growth in our practice may be partially attributable to patients who elect to be part time wear-ers—individuals who may have never considered wearing lenses in the past. We fi nd that with the now possible simplifi ed ap-proach, our patients are pleased that we have taken the time for their torics, maximizing their comfort and vision—while also preventing contact lens dropouts in our practice. RCCL

1. Morgan, P et al. International contact lens pre-scribing in 2015. Contact Lens Spectrum, January 2016.2. Read S, Collins MJ, Carney LG, Franklin RJ. The topography of the central and peripheral cornea. Invest Ophthalmol Vis Sci. 2006 April;47:1404-15.3. Momeni-Moghaddam H, Naroo SA, Askarizadeh F, Tahmasebi F. Comparison of fi tting stability of the diff erent soft toric contact lenses. Cont Lens Anterior Eye. 2014 Oct;37(5):346-50.

TAKING TORICS TO THE TOP

Fig 2. Off WTR astigmatism: If this axis was 15, round closer to the 180,

which would be axis 10. This gives us a fi nal lens power for our patient of

-1.50-0.75x180.

CASE REPORT: CUSTOM

VS. CONVENIENCE

A 27-year-old presented to the offi ce wearing a standard toric soft lens in one eye and a custom-made keratoconus lens on the other. With his toric soft lens he was 20/25 OD and with his custom lens 20/30 OS. With overrefraction he was able to achieve 20/20 with his standard soft lens but 20/20-3 with the custom lens. The latter was a quarterly replacement lens and he reported ideal comfort, but felt it a nuisance to remember two replacement systems. The patient is active in snowboarding and surfi ng. Standard refraction revealed -1.75 cylinder in his left eye with best corrected vision of 20/25-2.

Because his topography was not regular, we understood why his prior provider had placed him in a custom lens. We elected to trial fi t him into standard single-use lenses with toric parameters to see how much improvement we could achieve with a slightly stiff er modulus daily lens. We were able to achieve 20/25+2 vision. After discussion with the patient about the slight improvement and possible decreased aberrations he might have with the custom lens vs. the daily disposable lens, the patient elected to go with the daily disposable due to convenience and simplicity.

2017 MEETINGS

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REVIEW OF OPTOMETRYEDUCATIONAL MEETINGS OF CLINICAL EXCELLENCE

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2017

Hands-onWorkshops†February 17-21, 2017Winter Ophthalmic Conference

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Program Chairs:

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Aspen, CO

March 24-26, 2017

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Charleston, SC

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San Diego, CA

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Philadelphia, PA

OPTOMETRIC CORNEA, CATARACT AND REFRACTIVE SOCIETY

2017_Meetings_HouseAd-R8.indd 12017_Meetings_HouseAd-R8.indd 1 10/5/16 10:50 AM10/5/16 10:50 AM


Soft contact lenses come with myriad benefi ts and have served our patients well for over four decades. With a

wide range of new designs and materials, expanded prescription ranges and customization options, we can achieve great comfort and vision in many more patients than in the past. Toric soft lenses have improved greatly in recent years, expanding the pool of soft contact lens wearers. But where do you turn for astigmatic patients who have not been successful with any soft lens options you have tried? Scleral lenses may provide the solution for practitioners who feel they’ve run the gamut with soft lens options.

CANDIDATES FOR

SCLERAL LENSES

Ideal candidates include any patient with an irregular corneal surface. This includes patients with kera-toconus, pellucid marginal degen-eration, post-penetrating kerato-plasty (post-PKP), corneal scarring, irregularities following refractive surgery and ocular surface disor-ders. My experience has shown that patients with these conditions are most appreciative of the bene-fi ts that accompany scleral lenses. For some patients, fi tting sclerals may eliminate or delay the need for corneal transplant surgery.1,2

In addition, patients with ocular surface disease report less dryness

when wearing scleral lenses.3,4 In cases of ocular surface disease or persistent epithelial defects, scleral lens wear can facilitate healing and long-term corneal health, as they help maintain a smooth, wet and protected corneal surface.

Finally, sclerals are a great option for patients with otherwise healthy corneas who have very high prescriptions (high myopia, high hyperopia and high astigmatism). The gas permeable (GP) optics of scleral lenses provide excellent vi-sion because they center well, have minimal movement and are not dependent on rotational orientation to correct astigmatism.

BENEFITS FOR ASTIGMATS

More often than not, my patients with irregular corneas love scleral lenses. Irregular cornea patients who have switched from corneal GP lenses to sclerals report im-proved comfort, longer wearing time and better visual acuity.5 Here are fi ve benefi ts scleral lenses can provide to your irregular cornea patients:

Visual acuity. Scleral lenses provide excellent visual acuity due to the inherent stability and customization possible with GP lens optics.6 Rigid materials create a new front surface for the eye by positioning the tear lens between the scleral lens and the cornea, which corrects astigmatism and irregularities of the corneal sur-face. One study found keratoconus

patients who were fi t with scleral lenses had better acuity than when previously measured with corneal GP lenses.7 In patients who have residual astigmatism, scleral lenses can be customized with front toric optics. This astigmatic correction is placed on the front surface of the lens and requires a rotationally stable lens attained via double thin zones or toric peripheral curves. Scleral lenses can also incorporate multifocal designs to provide both distance and near vision for pres-byopes. The lenses center well and can be made rotationally stable as described above.

Comfort. With proper fi tting, scleral lenses prove to be extremely comfortable. Most people describe the feeling of a properly fi t scleral lens as being more comfortable

ABOUT THE AUTHOR

Dr. Lipson is an assistant

professor at University of

Michigan’s Kellogg Eye Cen-

ter, Department of Ophthal-

mology and Visual Science,

at the Northville location. His

clinical practice involves con-

tact lenses with an emphasis

on specialty lenses for overnight

corneal reshaping, keratoconus, post-corneal

transplant, post-refractive surgery and severe

dry eye. He conducts clinical research as

the principal investigator for studies on

corneal reshaping, vision-related quality of

life, myopia control and new lens designs.

He lectures nationally and internationally on

specialty contact lens and research topics. He

is a consultant for Bausch + Lomb’s Specialty

Vision Product (SVP) division, specializing in

education and training on specialty contact

lenses with emphasis on orthokeratology.

Dr. Lipson is the vice president of the Scleral

Lens Education Society and a fellow of the

American Academy of Optometry.

When to Opt forScleral Lenses

Irregular cornea patients in particular can enjoy the many benefi ts that accompany fi tting scleral lenses.

By Michael J. Lipson, OD


than soft lenses.8 Not only are they often more comfortable, in patients with irregular corneal curvature, scleral lenses also allow patients to wear lenses for longer periods each day compared with soft lenses.9

As practitioners are well aware, lens comfort is a major factor contributing to improvement in our patients’ vision-related quality of life (QOL).8 Studies show higher QOL scores for patients wearing sclerals compared with their previ-ous mode of correction.8,10 In one study of patients who had ocular surface disease, 45 of 49 (92%) re-ported improved quality of life due to the reduction of photophobia and discomfort.11 During the fi tting process, if patients have adverse effects such as lens awareness or discomfort, various changes in lens parameters such as diameter, edge lift, limbal clearance, toric periph-eral curves and overall sagittal depth can be modifi ed to make scleral lenses more comfortable. These design changes improve lens comfort by minimizing edge stand-off and ensuring the lens has no corneal or limbal bearing. Because of this adaptability, scleral lenses present a good alternative for a wide range of patients.

Performance. Due to their size, scleral lenses do not dislodge with quick eye movements. In addition, airborne particles and dust rarely get under the lens. My clinic sees signifi cantly fewer patients report-

ing foreign objects beneath their scleral lenses compared with soft lens options. Further, I’ve yet to see a case of lenses dislodging. Both of these factors make sclerals a good option for patients who play sports or lead active lifestyles.

Corneal health. Scleral lenses help maintain a healthy ocular sur-face.11 Because properly fi t sclerals vault the cornea, they maintain a layer of tears that continually bathes the cornea in moisture. In patients suffering from severe dry eye or any ocular surface disorder, scleral lenses provide an ongoing therapeutic effect by keeping the corneal surface protected from trauma, irritation, dehydration and desiccation.12

Delayed surgical intervention. The use of scleral lenses may delay or eliminate the need for corneal transplant surgery.1 If a patient has been unsuccessful with previous modes of contact lens correction, scleral lenses often provide a comfortable, less costly and more convenient solution than surgery, which comes with numerous fol-low-up visits, long-term eye drop use and a long recovery period.

LEARNING TO FIT SCLERALS

Most eye care practitioners already have the skills required to fi t scleral lenses. But, at the slit lamp, scleral lens fi tters need specifi c training to know what to look for. Three crit-

ical observations are necessary to establish proper fi t of a scleral lens:

First is central clearance. During diagnostic fi tting and evalua-tion, clinicians must evaluate the thickness of the tear fi lm with an optic section to ensure full corneal clearance, record for future use or give very specifi c information to a fi tting consultant as needed.

Second is evaluation of limbal clearance. Long-term bearing on the limbus will create irritation and redness.

Third is evaluation of the landing profi le. The goal is to achieve a uniform, gentle landing 360°. Excessive bearing will show im-pingement of conjunctival vessels and increasing redness over time, while excessive lift will create increased lens awareness.

Numerous resources can help you learn the necessary skills to gain confi dence in fi tting scleral lenses. The Scleral Lens Education Society (www.sclerallens.org) and the GP Lens Institute (www.gpli.info) are both excellent resources. Additionally, wet labs and fi tting workshops at national and regional specialty contact lens meetings are a great opportunity to learn general scleral skills in a hands-on setting. It is also worth noting that scler-al manufacturers hold dedicated webinars and workshops to help clinicians gain experience with a specifi c design.

Fitting scleral lenses isn’t a high-

tech endeavor; all you need is a

diagnostic lens fi tting set, slit lamp

and phoropter.

Photo: C

hristine Sindt, O

D

A decentered corneal GP lens

secondary to corneal irregularity.

Such a patient may experience a

better fi t with a scleral lens.

This well-centered scleral lens shows

no edge impingement or scleral

compression. Note the continuity of

blood vessels under the lens.


A 56-year-old male was referred to me complaining of poor vision in the right eye, although his left eye is fi ne. He had a history of radial keratotomy in both eyes in 1992 and LASIK in the right eye in 2003. He stated he needed better vision for all activities, but especially for golf. He inquired about additional sur-gery, glasses or contact lenses.

Other practitioners had tried a variety of CL fi tting modalities over the past six years. The latest correc-tion was a hybrid lens that provided good vision, but his comfort was not acceptable.

FINDINGS

• Unaided VA: OD 20/70-, OS 20/30+• Refraction: -1.25 -4.75 x 140 20/50 OD; +0.50 -1.25 x 080 20/25 OS• Slit lamp: Eight radial RK incisional scars and two “T-cuts” superior and inferior, as well as trace LASIK fl ap interface visible, superiorly-hinged OD; eight RK incisional scars OS.• Topography: Irregular astigmatism with inferior-nasal steepening OD.• Corneal diameter: 11.8mm

SOLUTION

After discussing and dismissing the potential of surgical correction and glasses, I educated him on scleral lenses and how diff erent they were than the previous contact lenses he had tried. Diagnostic

evaluation went well as far as comfort and vision correction. I used an ob-late back surface design to more closely parallel the post-refractive cor-neal topography.

First lens ordered: • BC: 9.24 oblate design• OAD: 16.0• Power: -7.00• Sagittal depth:4.40mm

At one-week follow-up he reported comfortable wearing time of eight hours, but he continued to wear them for a total of about 10 hours a day. He reported his visual acuity as quite good, and he read 20/25 with no distortions. Slit lamp evaluation showed moderate temporal hyperemia, 200 microns of central clearance and slight temporal conjunctival prolapse.

I ordered a new lens with a toric landing zone (90 microns fl atter in the horizontal meridian with no change vertically). With the new lens, one month later, he reported excellent vision (20/25+), comfort-able wearing time of 12 hours a day and only slight and occasional redness. He also reported much bet-ter vision on the golf course!

NOT FOR EVERY PATIENT

While part of the appeal of scleral lenses is the wide range of patients for whom they prove successful, there are some exceptions. A few patient characteristics may be con-traindications for scleral lenses:

• If, for example, you have a patient with a very small palpebral fi ssure with deep-set orbit, scler-als may not be the best option. These anatomical factors can make application of the lens diffi cult for patients.

• Most patients, even those with small eyes, can be taught to com-petently apply and remove scleral lenses. We do, however, occasion-ally come across a patient who just can’t do it and fi nds repeated attempts too frustrating to tolerate.

• Patients with low endothe-

lial cell counts (<800 cells/mm2) represent another contraindication for scleral lenses. This can occur with various corneal conditions but must be carefully evaluated in post-PKP patients. Patients with low endothelial cell counts who wear scleral lenses are more prone to signifi cant corneal edema and the potential for graft rejection reactions.13

Although not a contraindication, the presence of pre-existing central corneal scarring will limit the vision-correcting potential of any contact lens—including sclerals. But appearances of scarring can be deceiving, and clinicians should still provide a diagnostic fi tting for these patients; scleral lenses may still provide the best potential visual acuity.

COMPLICATIONS

As with any contact lens fi tting, complications can occur with scler-al lenses.13 Some include corneal neovascularization, limbal injec-tion, corneal/conjunctival infec-tion, corneal staining and corneal edema.

To minimize complications, cli-nicians should provide a thorough initial fi tting evaluation, patient education on proper disinfection and handling techniques, and careful follow-up procedures. In addition, the use of highly perme-able materials and special solutions during application can minimize the chance of patients experiencing these complications. These instanc-es, however, are rare and will occur less frequently with increased prac-titioner experience and confi dence.

WHEN TO OPT FOR SCLERAL LENSES

Corneal topography of the

right eye.

CASE 1


CASE 2Fitting your patients with irregular corneas with scleral

lenses can be gratifying and is a worthwhile skill set to incorporate into your practice. Scleral lenses can provide comfortable lens wear, clear vision and longer wear time.9 As a practitioner, it is rewarding to hear patients who were unsuccess-ful in other contact lens modalities report clear vision and an improved quality of life with properly fi t scleral lenses. Further, as sclerals are specialty lenses, they can gener-ate greater revenue per patient for your practice from higher fi tting fees and enthusiastic word-of-mouth referrals for other specialty patients. RCCL

1. Deloss KS, Fatteh NH, And Hood CT. Prosthetic replacement of the ocular surface ecosystem(PROSE) scleral device compared to keratoplasty for the treatment of corneal ectasia. Am J Oph-thal. 2014;158:974-82.2. Severinsky B, Behrman S, Frucht-Pery J, Solo-mon A. Scleral contact lenses for visual rehabil-itation after penetratingkeratoplasty: Long term outcomes. Cont Lens Ant Eye. 2014;37:196-202.3. Schornack MM, Baratz KH, Patel SV, Maguire LJ. Jupiter scleral lenses in the management of chronic graft versus host disease. Eye Cont Lens. 2008;34(6):302-5.4. Rosenthal P, Cotter J. The Boston scleral lens in the management of severe ocular surface dis-ease. Ophthalmol Clin N Am. 2003;16:89-93.5. Segal O, Barkana Y, Hourovitz D, et al. Scleral lenses may help where other modalities fail. Cornea. 2003;22:308-10.6. Stason WB, Razavi M, Jacobs DS, et al. Clinical benefi ts of the boston ocular surface prosthesis. Am J Ophthalmol 2010;149:54–61.7. Schornack MM, Patel SV. Scleral lenses in the management of keratoconus. Eye Contact Lens 2010;36:39-44.8. Bergmanson JP, Walker MK and Johnson LA. Assessing scleral contact lens satisfaction in a keratoconus population. Optom Vis Sci 2016;93. Epub ahead of print.9. Ortenberg I, Behrman S, Geraisy W and Bare-quet I. Wearing time as a measure of success of scleral lenses for patients with irregular astigma-tism. Eye Contact Lens. 2013;39:381-4.10. Visser E-S, Visser R, van Lier H, Otten H. Mod-ern scleral lenses part II: patient satisfaction. Eye Contact Lens. 2007;33:21-5.11. Romero-Rangel T, Stavrou P, Cotter J, et al. Gas permeable scleral contact lens therapy in oc-ular surface disease. Am J Ophthal. 2000;130:25-32.12. Van der Worp E, Bornman D, Ferreira DL, et al. Modern scleral lenses: a review. Cont Lens Ant Eye. 2014;37:240-50.13. Walker MK, Bergmanson JP, Miller WL, et al. Complications and fi tting challenges associated with scleral contact lenses: A Review. Cont Lens and Ant Eye. 2015;39:88-96.

A 29-year-old male was referred to me with a history of keratoconus in both eyes. When he was fi rst diagnosed at 19, he was prescribed corneal GP lenses. He wore those for about fi ve years with varying degrees of comfort. After hearing about new contact lens options for keratoconus, he pursued other modalities over the next fi ve years, including: piggyback, hybrid and special soft lenses.

He came in wearing the special soft lenses that provided good comfort, but he complained that vision was not acceptable and that he had to replace them every two months due to deposits.

FINDINGS

• Current corrected VA: 20/30- OD, 20/40 OS.• Refraction: -4.25 -4.75 x80 20/70 OD, -5.50 -5.25 x 115 20/80 OS.• Slit lamp: Apical thinning and 1-2+ vertical striae OD; apical thinning, 2+ vertical striae and trace hazy scar OS.• Topography: Irregular astigmatism with inferior temporal steepening and inferior temporal apex OU.• Corneal diameter: 12.0mm

SOLUTION

After discussing his history and various contact lens options, I recom-mended we proceed with scleral lenses.

Diagnostic evaluation for fi tting his left eye went well. He was happy with both the vision and comfort with the scleral lenses. I used a prolate back surface design in a 17.0mm lens.

Initial diagnostic lens for the left eye:• Sagittal depth: - 4900 microns• Base curve: -7.8• Diameter: 17.0• Power: -2.00• Over-refraction: 3.50 sph 20/20-

The initial diagnostic lens showed slight central bearing but good limbal clearance and good edge alignment.

The fi rst lens I ordered had 150 microns greater sagittal depth than the diagnostic lens.

First lens ordered for the left eye: • Sagittal depth: 5050 microns • BC; 7.80 prolate design• OAD: 17.0• Power: -5.50

At one-week follow-up he reported comfort-able wearing time of 14 hours and reported not needing to use any lubricating drops. He reported his visual acuity in his left eye as very good, and he read 20/20- with no distortions. Slit lamp evaluation showed minimal hyper-

emia that did not change with increased wearing time.

Corneal topography of

the left eye.

The patient’s left eye

after wearing the

prescribed scleral lens

for six hours.

Initial diagnostic

lens showed

small central

bearing.


Eye care practitioners are familiar with corneal astigma-tism, as this common refractive condition

caused by unequal curvature along the two principal meridi-ans greets us in the exam chair every day. Classifi ed by axis, astigmatism is either with-the-rule (WTR), against-the-rule (ATR) or oblique; it can be further categorized as regular or irregular. These terms and their clinical manifestations are a part of routine practice; however, the advent of wavefront analysis in recent years has enhanced our understanding of irregular astig-matism with the classifi cation of higher-order aberrations such as coma, trefoil and quadrafoil.1

The portfolio of options for the surgical correction of astig-matism has expanded signifi -cantly over the past two decades. Photorefractive procedures such as laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) are well established. The introduction of femtosecond-laser (FS) tech-nology has opened the door for new surgical strategies including laser-assisted cataract surgery and the recently FDA approved small-incision lenticule extraction (SMILE) procedure. Meanwhile, incisional options such as astig-matic keratotomy (AK) continue

to evolve as FS technology adds a level of precision not seen with manual techniques. FS lasers can be combined with toric intraoc-ular lenses (IOLs) to address the growing demand for refractive cataract surgery.

Surgical correction of astig-matism has a promising future. Improved strategies are evolving in the areas of topography-guid-ed laser procedures, ray trac-ing, patterned corneal collagen crosslinking and toric multifocal intraocular lenses.2,3

THE RISING TIDE

Astigmatism accounts for about 13% of all refractive error.4 As much as 90% of the world’s population has some degree of astigmatism, including 20% with 1.5D or more cylinder.5

Approximately 63% of individu-als under 40 have 0.25D or more astigmatism, while most have less than 1D.6-8

Research reveals that myopia and astigmatism are increasing at an alarming rate, both surfacing at a younger age and growing in prevalence throughout the early and adolescent years.9,10 In the United States, myopia prevalence is nearly twice what it was 30 years ago.11-13 In 2015, investi-gators found that 50% of urban populations in East Asia were myopic, with 90% of university students displaying myopia or

myopic astigmatism.10 Research estimates that myopia—and presumably myopic astigma-tism—will affect nearly six billion people by the year 2050.13

This astonishing rise has ramifi -cations for eye care professionals around the world involved in the prevention, management and surgical correction of myopia and astigmatism.

FROM AK TO SMILE:

A RETROSPECTIVE ON

SURGICAL METHODOLOGY

Astigmatic keratotomy was one of the fi rst forms of refractive surgery developed to correct astigmatism. AK became avail-able in the United States shortly after radial keratotomy (RK) was introduced in 1978.14 During AK, peripheral arcuate incisions are made with a diamond blade knife along the steep axis of corneal astigmatism to fl atten that axis.15

Though RK has fallen out of favor due to diurnal fl uctuation in acuity and unpredictable long-term results, AK is still a conve-

Dr. Brown is clinical director of

TLC Laser Eye Centers of Bos-

ton, MA, and Providence, RI.

She is a member of the TLC

Clinical Director Advisory

Group and holds a faculty

appointment at the New

England College of Optometry.

She is involved in clinical research,

teaching and lecturing.

ABOUT THE AUTHOR

1 CE Credit (COPE Approval

Pending)

SURGICAL OPTIONS for the

Correction of ASTIGMATISMToday’s sophisticated surgical tools and techniques off er dramatically improved outcomes over the imprecise early eff orts of yesterday.

By Kristen Brown, OD


nient, relatively inexpensive pro-cedure. Compared with LASIK or PRK, however, astigmatic ker-atotomy is less predictable and has a lower range of astigmatic effect.16-19

The application of FS lasers has given surgeons better control of the length, depth and location of AK incisions, leading to fi ner pre-cision, less risk and better visual outcomes.20-23 A big advantage of FS AK is that cuts can be pene-trating or intrastromal without a break in the epithelium. This allows for titration of the effect and better patient comfort.24

Low to moderate astigmatism (1D to 3D) can also be corrected with intracorneal ring segments (ICRS). The goal of ICRS im-plantation is typically to delay or prevent corneal graft surgery; it is most often employed in ectatic conditions such as keratoconus, post-LASIK ectasia and pellucid marginal degeneration.25 As with AK, ICRS can be done manually or with an FS laser to create tun-nels that are more precise, more predictable and associated with fewer complications and similar visual outcomes.26

Photoablation with an excimer laser (i.e., LASIK and PRK) has become the prevailing surgical option for patients who desire an alternative to eyeglasses and contact lenses. The FDA fi rst approved the excimer for spher-ical myopia in 1995, but the option to treat astigmatism and hyperopia didn’t become avail-able until several years later. A 2004 study found that one to two million people in the United States undergo LASIK or PRK.27

US Military personnel opt for re-fractive laser surgery at twice the rate of the general population.28

Adverse events such as dry eye symptoms, night vision distur-

bances (ghosting, glare or halo) and residual refractive error are rare and most resolve after the fi rst year.28 Customized ablation profi les materialized about a decade ago when aberrometers became available to measure the wavefront of the eye.

Wavefront data is obtained by projecting a fl at plane or “wave” of light into the eye and measuring the location of the corresponding light spots refl ect-ed from the retina. The relative location of refl ected light is then used to calculate the power of the optical system where each spot of light enters the eye. The goal of custom or wavefront-guided (WFG) laser ablation is to reduce the imperfections or higher-or-der aberrations (HOAs) of the optical system.29 Original “con-ventional” laser ablation profi les with the very fi rst excimer lasers did not aim to correct HOAs and tended to create an oblate (centrally fl at) corneal profi le. They were also more likely to induce postoperative HOAs like spherical aberration. Wavefront-optimized (WFO) ablations were also designed to customize laser ablations but do not rely on wavefront measurement of the eye. WFO treatments are based on refraction data, keratometry and a peripheral ablation pro-fi le specifi c to each cornea. This peripheral algorithm results in a more prolate corneal shape

following laser ablation and is thought to induce fewer postop-erative HOAs.30

Custom ablations are indicated for myopia as high as -12D with astigmatism up to -3.75D on

Release Date: November 2016Expiration Date: November 1, 2019Goal Statement: Surgical correction of astigmatism has a promising future. This article discusses the improved strategies that are evolving in the areas of topography-guided laser procedures, ray tracing, patterned corneal collagen crosslinking and toric intraocular lenses.Faculty/Editorial Board: Kristen Brown, OD Credit Statement: COPE approval for 1 hour

of continuing education credit is pending for this course. Check with your state licensing board to see if this counts toward your CE requirements for relicensure.

Joint-Sponsorship Statement: This contin uing education course is joint-sponsored by the Pennsylvania College of Optometry.

Disclosure Statement: The author has no financial interest in any products mentioned in this article.

The same patient three months after

combined one-site cataract and

trabeculectomy surgery with LRI. In

retroillumination, we can verify the

rotational stability of the lens at 80°.

Photo: A

llister Gibbons, M

D

Preoperative topography of a

patient’s left eye prior to having

undergone a combined one-site

cataract and trabeculectomy surgery

with LRI. Regular 5.5D of with-the-

rule astigmatism can be seen with an

axis of 80°.

Photo: A

llister Gibbons, M

D


SURGICAL OPTIONS FOR THE CORRECTION OF ASTIGMATISM

most wavefront-guided excimer laser platforms. Similarly, wave-front-optimized ablation profi les can correct up to -12D myopia and provide an expanded range of astigmatism correction—up to -6D, for example—with the Wavelight EX500 excimer laser (Alcon).

Wavefront-guided visual outcomes have been excellent compared with conventional ab-lation profi les; however, they are dependent of aberrometry mea-surements which are affected by pupil size, pupil centration and accommodation.31 In addition, corneal, lens and vitreous opac-ities limit the ability to capture good wavefront data. As lenticu-lar aberrations change over time, correcting the wavefront of the whole eye may not be an optimal strategy for treating irregular astigmatism and other HOAs.

TOPOGRAPHY-GUIDED

LASER ABLATION

Refractive surgeons in the United States can now perform topogra-phy-guided laser ablation, which been growing in popularity out-side the United States for many years.32 The FDA granted approv-al for topography-guided treat-ment on normal (i.e., previously untreated) eyes on the Nidek laser in October of 2013 and the Alcon laser system in 2015.

Topography-guided ablation normalizes or smooths the corne-al surface by correcting only the HOAs that arise from the cor-nea, leaving internal aberrations unchanged. Topography-guided technology integrates placido disc topography, keratometry and pupillometry in a single diagnostic device that integrates with planning software and excimer laser technology.32 Unlike with WFG ablations, informa-

tion about sphere and regular astigmatism (the lower-order aberrations) is not captured by topography and must be obtained separately, by refraction, for example.

Recent research evaluating the safety and effectiveness of topography-guided LASIK found that visual symptoms such as glare, halo and starbursts were reduced—and, more surprisingly, 30.9% of subjects gained one or more lines of uncorrected visual acuity compared with preopera-tive best corrected visual acuity.32 Outside the United States, topog-raphy-guided procedures can be conducted on highly aberrated eyes such as those with small or decentered optical zones from previous corneal refractive sur-gery, eyes with naturally occur-ring irregular corneal astigmatism or irregular astigmatism from trauma.33,34

With age, the axis of astigma-tism shifts toward an ATR orien-tation primarily due to changes in the cornea, not the lens. A reduction in eyelid tension over time may partly explain this shift, as internal astigmatism remains relatively stable with age.35

Despite minimally invasive approaches, modern cataract sur-gery can induce corneal astigma-tism even with the small incisions made in the peripheral cornea. Like AK, incisions made for cat-aract surgery entry wounds cause fl attening in the meridian incised and steepening in the meridian 90 degrees away.36 Superior incisions cause fl attening of the vertical meridian or an increase in ATR astigmatism, while temporal incisions lead to fl attening in the horizontal meridian or an in-crease in WTR astigmatism. The amount varies with individual differences in corneal biomechan-

ical properties, surgical technique and type of surgery performed.37 Understanding and manag-ing surgically induced corneal astigmatism (SICA) is necessary for surgeons to succeed in an era of patients opting for refractive cataract surgery, which includes post-op uncorrected emmetropia as a goal. Many have had previ-ous LASIK or PRK and expect to return to post-laser, spectacle-free status.

LRIs AND IOLs

During cataract surgery, corneal astigmatism can be corrected with limbal relaxing incisions (LRIs), toric IOLs or a combi-nation of the two. In addition, a femtosecond laser can be em-ployed to assist the surgeon with steps that are typically performed manually. Laser-assisted cataract surgery (LACS) adds a level of precision to the procedure, which may improve visual outcomes and lessen the risk of postop-erative complications such as endothelial cell loss and macular edema.38 LRIs are positioned more peripherally in the cornea than AK incisions and are pre-ferred in cataract surgery since the same incision can be used for phacoemulsifi cation. Compared with astigmatic keratotomy, LRIs are associated with less pain and less induced irregular astigma-tism.39 Further, they are quick and effective at reducing up to 1.5D of corneal astigmatism.

Toric IOLs are a better option for surgical correction of moder-ate (1.5D to 4.25D) astigmatism. Several toric IOLs of various material and astigmatic pow-er are available in the United States, including the Staar Toric (Staar Surgical), Acrysof IQ Toric (Alcon), Tecnis Toric (AMO) and Trulign Toric (Bausch + Lomb).


For successful correction of astigmatism, toric IOLs must be aligned with the visual axis and the steep meridian of the cornea. Some lenses can rotate, which will reduce the effectiveness and leave residual astigmatism at a new, often oblique, meridian.

Anterior and posterior cor-neal astigmatism must both be considered when planning IOL surgery—particularly in patients who want less dependence on spectacle correction. Inaccuracies arise when posterior corneal astigmatism is measured with the assumption that there is a fi xed-ratio relationship with the anterior corneal curvature.40 The Cassini Corneal Shape Analyzer (i-Optics) is a new topographer that uses LED ray tracing tech-nology with 700 diode lights to measure anterior and posterior corneal astigmatism. Advances in cylinder and axis measurement precision can be useful for pre-operative planning of toric IOL implants, particularly in post-la-ser refractive surgery patients.41

In addition, the use of in-traoperative aberrometry can guide IOL power selection. The Optiwave Refractive Analysis system (Alcon) employs wave-front interferometry to produce a fringe pattern; distortions in this pattern are then translated into refractive values.42 Research on toric IOL power selection aided by intraoperative aberrometry reveals that patients were 2.4 times more likely to have less than 0.50D of residual refractive astigmatism when an intraopera-tive aberrometer was used.43

Advantages of LACS over manual cataract surgery include the customization of corne-al incisions, precision and the centration of the capsulotomy for improved refractive stability and

predictability. Fragmenting the lens before phacoemulsifi cation is another advantage of LACS that is believed to be less likely to induce endothelial cell loss.43 For astigmatism greater than 4.25D

at the corneal plane, it may be necessary to combine LRIs with toric IOLs or subsequent LASIK or PRK for up to 10D corneal astigmatism correction.

The newest frontier combines

Pre-op topography (Vario, Alcon) of a highly astigmatic patient to be treated

with Wavelight FS200/EX500 (Alcon) wavefront optimized system. Left

image: +4.25 -4.75x175 20/25 OD. Right image: +4.50 -5.25x005 20/25 OS.

Pentacam imaging of the same WFO-treated patient (right eye only). Left

image: pre-op OD. Right image: one month post-op OD.

At one month post-op, UCVA is 20/20 plano -0.25x005 20/20 OD.


SURGICAL OPTIONS FOR THE CORRECTION OF ASTIGMATISM

astigmatism and presbyopia treat-ment in one IOL. The recently FDA approved Tecnis Symfony Toric IOL (AMO) and the forth-coming Acrysof IQ Restor Toric (Alcon) are two early entrants into this emerging category.

NO LONGER AN

AFTERTHOUGHT

Although signifi cant astigma-tism is typically defi ned as 1D or more, amounts as low as 0.25D can impact visual acuity or visual quality in some individ-uals. Planning and predicting the outcome of refractive surgery is the foremost challenge a surgeon faces. With the explosion of more advanced technology and im-proved surgical outcomes, there is increasing expectation that refractive procedures can and will provide excellent visual results with minimal risk, and that astigmatism correction must now be part and parcel of the surgical approach. Future advances will focus on corneal biomechanical properties and wound healing response, which is one of the few remaining limitations affecting the predictability and stability of refractive surgery. RCCL

1. Kelly JE, Mihashi T, Howland HC. Compensation of corneal horizontal/vertical astigmatism, lateral coma and spherical aberration by internal optics of the eye. J Vision. 2004;4:262–71.2. Cummings AB, Kelly GE. Optical ray trac-ing-guided myopic laser in situ keratomileu-sis:1-year clinical outcomes. Clinical Ophthalmolo-gy. 2013;7:1181–91.3. Ibrahim Seven MS, Sinha Roy A, Dupps WJ Jr. Patterned corneal collagen crosslinking for astigmatism: Computational modeling study. J Cataract Refract Surg. 2014 June;40(6):943–53.4. Read SA, Collins MJ, Carney LG. A review of astigmatism and its possible genesis. Clin Exp Optom. 2007;90(1):5–19.5. Porter J, Guirao A, Cox IG, Williams DR. Mono-chromatic aberrations of the human eye in a large population. J Opt Soc Am A. 2001;18:1793–1803.6. Ferrer-Blasco T, Montés-Micó R, Peixo-to-de-Matos SC, et al. Prevalence of corneal astigmatism before cataract surgery. J Cataract Refract Surg. 2009;35:70-5.7. Saunders H. Age-dependence of human refractive errors. Ophthalmic Physiol Opt. 1981;(1):159–74.

8. Fledelius HC, Stubgaard M. Changes in refrac-tion and corneal curvature during growth and adult life. A cross-sectional study. Acta Ophthal-mol. 1986;64:487–91.9. Gwizada J, Grice K, Held R, et al. Astigmatism and the development of myopia in children. Vision Research. 2000;40:1019–26.10. Smith MJ, Walline JJ. Controlling myopia progression in children and adolescents. Adolesc Health Med Ther. 2015;6:133-40.11. Read SA. Ocular and environmental factors associated with eye growth in childhood. Optom Vis Sci. 2016;93:1031–41.12. Rose KA, Morgan IG, Ip J, et al. Outdoor activ-ity reduces the prevalence of myopia in children. Ophthalmology. 2008;115:1279–85.13. Holden BA, Fricke TR, Wilson DA. Global prev-alence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology. 2016 May;123(5):1036-42.14. Waring GO. Refractive keratotmy for myopia and astigmatism. St Louis, MO: Mosby-Year Book; 1992.15. Hanna KD, Jouve FE, Waring GO 3rd, Ciarlet PG. Computer simulation of arcuate keratotomy for astigmatism. Refract Corneal Surg. 1992 Mar-Apr;8(2):152-63.16. Waring GO 3rd, Lynn MJ, McDonnell PJ. Results of the prospective evaluation of radial keratotomy (PERK) study 10 years after surgery. Arch Ophthalmol. 1994;112(10):1298-308.17. Kemp JR, Martinez CE, Klyce SD, et al. Diurnal fl uctuations in corneal topography 10 years after radial keratotomy in the Prospective Evaluation of Radial keratotomy Study. J Cataract Refract Surg. 1999 Jul;25(7):904-10. 18. Kohnen T, Buhren J. Corneal fi rst-surface ab-erration analysis of the biomechanical eff ects of astigmatic keratotomy and a micro-keratome cut after penetrating keratoplasty. J Cataract Refract Surg. 2005;31:185–9. 19. Montes-Mico R, Munoz G, Albarran-Diego C, et al. Corneal aberrations after astigmatic keratoto-my combined with laser in situ keratomileusis. J Cataract Refract Surg. 2004;30:1418–21. 20. Abbey A, Ide T, Kymionis GD, Yoo SH. Fem-tosecond laser-assisted astigmatic keratotomy in naturally occurring high astigmatism. Br J Ophthalmol. 2009;93(12):1566–9.21. Hoff art L, Proust H, Matonti F, et al. Correction of post-keratoplasty astigmatism by femtosecond laser compared with mechanized astigmatic kera-totomy. Am J Ophthalmol. 2009;147(5):779–87.22. Oshika T, Shimazaki J, Yoshitomi F, et al. Arcuate keratotomy to treat corneal astigmatism after cataract surgery: a prospective evaluation of predictability and eff ectiveness. Ophthalmology. 1998;105(11):2012–6.23. Aristeidou A, Taniguchi EV, Tsatsos M, et al. The evolution of corneal and refractive surgery with the femtosecond laser. Eye and Vision. 2015 Jul 14;2:12.24. Bahar I, Levinger E, Kaiserman I, et al. IntraLase-enabled astigmatic keratotomy for post-keratoplasty astigmatism. Am J Ophthalmol. 2008;146(6):897–904.25. Cosckunseven E, Kymionis GD, Tsiklis NS, et al. One-year results of intrastromal corneal ring segment implantation (KeraRing) using femto-second laser in patients with keratoconus. Am J Ophthalmol. 2008;145(5):775–9.26. Piñero DP, Alio JL, El Kady B, et al. Refractive and aberrometric outcomes of intracorneal ring segments for keratoconus: mechanical versus femtosecond-assisted procedures. Ophthalmolo-gy. 2009;116(9):1675–87.27. Duff ey RJ, Leaming D. Trends in refractive

surgery in the United States. J Cataract Refract Surg. 2004;30(8):1781–5.

28. Blitz JB, Hunt DJ, Cost AA. Post Refractive surgery complications and eye disease, active duty US armed forces 2005-2014. MSMR. May 2016;23(5).

29. Subbaram MV, MacRae SM. Customized LASIK treatment for myopia based on preoperative manifest refraction and higher order aberrometry: the Rochester nomogram. J Refract Surg. 2007 May;23(5):435-41.

30. Randleman JB et al. Outcomes of wave-front-optimized surface ablation. Ophthalmology 2007 May;114(5):983-8.

31. Sáles CS, Manche EE. One-year outcomes from a prospective, randomized, eye-to-eye com-parison of wavefront-guided and wavefront-op-timized LASIK in myopes. Ophthalmology. 2013 Dec;120(12):2396-402.

32. Stulting RD, Fant BS, The T-CAT Study Group. Results of topography-guided laser in situ keratomileusis custom ablation treatment with a refractive excimer laser. Cataract Refract Surg. 2016 Jan;42(1):11-8.

33. Alio JL, Belda JI, Osman AA, Shalaby AMM. Topography-guided laser in situ keratomileusis (TOPOLINK) to correct irregular astigmatism after previous refractive surgery. J Refract Surg. 2003;19:516–27.

34. Lin DT, Holland S, Tan JC, Moloney G. Clin-ical results of topography-based customized ablations in highly aberrated eyes and kerato-conus/ectasia with cross-linking. J Refract Surg. 2012;28(11 suppl):S841-8.

35. Anstice J. Astigmatism—Its components and their changes with age. Am J Optom Arch Am Acad Optom. 1971;48:1001–6.

36. Simsek S, Yaşar T, Demirok A, et al. Eff ect of superior and temporal clear corneal incisions on astigmatism after sutureless phacoemulsifi cation. J Cataract Refract Surg. 1998;24:515–8.

37. Dupps WJ Jr, Wilson SE. Biomechanics and wound healing in the cornea. Exp Eye Res. 2006;83(4):709-20.

38. Callou TP, et al. Advances in femtosecond laser technology. Clinical Ophthalmology 2016:10 697–703.

39. Settas G, Settas C, Minos E, et al. Photore-fractive keratectomy (PRK) versus laser assisted in situ keratomileusis (LASIK) for hyperopia correction. Cochrane Database Syst Rev. 2012;(6): CD007112.

40. Koch DD. The posterior cornea: hiding in plain sight. Ophthalmology. 2015;122(6):1070–1.

41. Kanellopoulos J, Asimellis G. Distribution and repeatability of corneal astigmatism measure-ments (magnitude and axis) evaluated with color light emitting diode refl ection topography. Cornea. 2015;34(8):937–44.

42. Huelle JO, Katz T, Druchkiv V, et al. First clinical results on the feasibility, quality and reproducibility of aberrometry-based intraoper-ative refraction during cataract surgery. British J Ophthalmol. 2014;98(11):1484-91.

43. Hatch KM, Woodcock EC, Talamo JH. Intra-ocular lens power selection and positioning with and without intraoperative aberrometry. J Refract Surg. 2015;31(4):237–42.


CE TEST ~ NOVEMBER 2016 EXAMINATION ANSWER SHEET

Surgical Options for the Correction of Astigmatism

Valid for credit through November 1, 2019

Online: This exam can also be taken online at www.reviewofcontactlenses.com. Upon passing the exam, you can view your results immediately. You can also view your test history at any time from the website.

Directions: Select one answer for each question in the exam and completely darken the appropriate circle. A minimum score of 70% is required to earn credit.

Mail to: Jobson Optometric CE, Canal Street Station, PO Box 488 New York, NY 10013

Payment: Remit $20 with this exam. Make check payable to Jobson Medical Information LLC.

Credit: COPE approval for 1 hour of CE credit is pending for this course.

Sponsorship: Joint-sponsored by the Pennsylvania College of Optometry

Processing: There is an eight-to-10 week processing time for this exam.

Answers to CE exam:

1. A B C D 6. A B C D

2. A B C D 7. A B C D

3. A B C D 8. A B C D

4. A B C D 9. A B C D

5. A B C D 10. A B C D

Evaluation questions (1 = Excellent, 2 = Very Good, 3 = Good, 4 = Fair, 5 = Poor)Rate the effectiveness of how well the activity: 11. Met the goal statement: 1 2 3 4 5

12. Related to your practice needs: 1 2 3 4 5

13. Will help improve patient care: 1 2 3 4 5 14. Avoided commercial bias/influence: 1 2 3 4 5

15. How do you rate the overall quality of the material? 1 2 3 4 5

16. Your knowledge of the subject increased: Greatly Somewhat Little 17. The difficulty of the course was: Complex Appropriate Basic

18. How long did it take to complete this course? _________________________

19. Comments on this course: _________________________________________

___________________________________________________________________

20. Suggested topics for future CE articles: ______________________________

___________________________________________________________________

Identifying information (please print clearly):

First Name

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The following is your: Home Address Business Address

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By submitting this answer sheet, I certify that I have read the lesson in its entirety and completed the self-assessment exam personally based on the material present-ed. I have not obtained the answers to this exam by fraudulent or improper means.

Signature: ________________________________________ Date: _____________

Please retain a copy for your records. LESSON 113633, RO-RCCL-1116

1. Which of the following procedures was first used to correct astigmatism?

a. Toric intraocular lenses.b. LASIK.c. Astigmatic keratotomy.d. Small-incision lenticule extraction.

2. Which procedure is associated with fluctuation in vision and unpredictable

results long term?

a. PRK.b. Laser-assisted cataract surgery.c. Radial keratotomy.d. Astigmatic keratotomy.

3. Which statement is true regarding custom excimer laser ablation (LASIK/

PRK)?

a. Custom laser ablation treats higher-order and lower-order aberrations.b. Custom laser vision correction treats only lower-order aberrations.c. Custom laser ablation treats only higher-order aberrations.d. Custom laser ablation treats neither higher-order nor lower-order aberrations.

4. Wavefront data is obtained by which device?

a. Phoropter.b. Aberrometer.c. Keratometer.d. Pupillometer.

5. Topography-guided laser ablation corrects:

a. Internal aberrations.b. Lenticular opacities.c. Hyperopia.d. Aberrations of the corneal surface.

6. Normalizing the corneal surface with topography-guided laser ablation:

a. Has been associated with improved uncorrected acuity over preoperative best-corrected acuity in some patients.b. Has been associated with a high risk of losing best-corrected acuity in many patients.c. Is not currently FDA approved in the United States.d. Corrects only symmetric corneal astigmatism.

7. Toric Intraocular lenses are a good option for patients with:

a. A low amount of internal astigmatism.b. A moderate to high amount of corneal astigmatism.c. Macular degeneration.d. A moderate amount of lenticular toricity.

8. Which statement is true regarding limbal relaxing incisions?

a. Should never be combined with toric intraocular lenses.b. Should only be performed manually.c. Can be performed with an excimer laser.d. Can be performed with a femtosecond laser.

9. Which statement is false regarding femtosecond laser technology?

a. The use of FS lasers in ocular surgery has expanded significantly over the past 20 years.b. The use of FS lasers in ocular surgery peaked then faded in popularity over the past 10 years.c. FS lasers are used to create corneal flaps in LASIK, corneal incisions in cataract surgery and lenticule creation in the SMILE procedure.d. FS lasers are high-energy, high-speed lasers that can be used to improve the precision of ocular surgery.

10. Which statement is accurate regarding the surgical options for correction of

astigmatism?

a. Surgical correction of astigmatism is not relevant during cataract surgery.b. Correction of even small amounts of astigmatism is important in refractive surgery.c. The ability to correct mild to severe astigmatism has improved significantly over the past 20 years.d. Both b and c.


HistoryA 39-year-old Caucasian male pre-sented on referral for keratoconus care after relocating from another city. He reported wearing a con-tact lens (SynergEyes ClearKone) only in the right eye. He indicated an inability to tolerate wearing any contact lens in his left eye, including a corneal rigid lens, pig-gyback system with a corneal rigid lens and various hybrid contact lenses. He did not use any eye-glasses. Family ocular history was

unremarkable, he denied taking any regular medication and had no known drug allergies. He had no previous ocular surgery, and general health was unremarkable.

Diagnostic DataUnaided visual acuity was 20/100 OD and 20/400 OS. Autorefraction yielded readings of -2.50 -5.25X066 OD and no obtainable measurement OS. Manifest refraction was -2.50-6.00X065 OD yielding 20/30, and

gave no improvement OS. Corneal topography showed asymmetric corneal steepening OU, with sig-nifi cant irregularity, especially OS (Figure 1).

Contact lens evaluation of his SynergEyes ClearKone lenses OU

Solving Scleral Contact LensInduced Pingueculitis

A B S T R AC T

This case report describes the steps taken to solve scleral lens-induced pingueculitis in a keratoconus patient by refi tting the patient into a smaller diameter scleral lens. A discussion ensues on other possible treatments, including lens notching, micro vaults, increasing lens diameter and hybrid lenses.

Keywords: Pinguecula, pingueculitis, scleral lens, contact lenses, keratoconus

I N T R O D U C T I O N

Keratoconus is the prototypical, naturally-occur-ring condition typifi ed by elevated lower and high-er-order aberrations due to a distorted cornea.1 The primary treatment for visual rehabilitation is a rigid contact lens to re-establish a smooth refracting sur-face so the tear lens underneath optically neutralizes the aberrations resulting from the irregular corneal surface.2 Although a simple concept, it is frequently undermined by a host of factors, including: inability to sustain comfortable lens wear; diffi culty with lens handling; poor ocular physiology, such as corneal abrasions,3-9 corneal staining and other epitheliopa-thy, vascularized limbal keratopathy or DuBois ring; and lens dislodgement and ejection.

Scleral contact lenses have gained popularity as an effective treatment to restore vision in keratoconus and other thinning disorders, including in patients who have previously failed in traditional corneal gas permeable (GP) and hybrid contact lenses.3,4 Patients wearing scleral lenses often report excellent comfort, most likely because the lenses vault the sensitive cornea and rest on the relatively insensitive conjunctiva and underlying sclera.3,5,6

A common challenge to successful scleral lens wear is the presence of a pinguecula on the conjunctiva, which may mechanically interact with the landing area of the lens, causing redness and discomfort.7,8 In one study, nearly half of the population had a pinguecula.9 While the elective contact lens wearer can discontinue contact lens wear and use glasses, most patients with keratoconus require the functional vision that only rigid-surface contact lenses can provide. The prospect of excellent vision at the cost of eye redness and discomfort is not acceptable—nor is poor vision with a comfortable, white eye. However, keratoconus patients with pingueculitis due to scleral contact lens wear can often remain in this modality with appropriate lens modifi cation.

C A S E R E P O R T B Y B R I A N C H O U , O D

C A S E R E P O R T

The simplest option is often the best solution.

ABOUT THE AUTHOR

Dr. Chou is a partner at

EyeLux Optometry in San

Diego, CA, where he directs

a referral-based keratoconus

clinic.

C A S E R E P O R T


was performed, including assess-ment of his left lens, which he did not wear due to discomfort. High molecular weight fl uorescein was applied and showed an optimal fl uorescein pattern OD with good centration and approximately 150 microns of central vault, and an alignment relationship over the inner landing zone (ILZ). The fl u-orescein pattern OS showed hard apical bearing with inferior decen-tration, with an alignment rela-tionship over the ILZ and no skirt fl uting. Contact lens acuity was 20/25 OD with spherocylindrical overrefraction of +0.75-0.75X140 yielding 20/20, and 20/25 OS with spherical overrefraction of -0.50 DS yielding 20/25+.

Biomicroscopy revealed that lids and lashes were normal, while the conjunctiva and sclera were unremarkable with no obvious conjunctival elevations. The right cornea showed iron deposition (Fleischer’s ring) and no apical scarring. The left cornea also showed a Fleischer’s ring, grade 2+ apical scarring and vertical folds at the level of Descemet’s (Vogt’s striae). Anterior chambers were deep and quiet, and the irides were healthy with normal anatomy.

Dilated examination was per-formed using a 78D condensing lens and biomicroscope, and using a 20D condensing lens with bin-ocular indirect ophthalmoscopy. Crystalline lenses were clear, and anterior vitreous showed no lique-faction. Optic nerves were healthy with full neuroretinal rim tissue with C/D ratios of 0.2. Retinal vasculature, maculae and retinal peripheries were normal as well.

DiagnosisI diagnosed keratoconus OS > OD with contact lens discomfort OS attributable to the pronounced corneal distortion causing me-

chanical interaction with the hybrid lens.

TreatmentI did not prescribe glasses because the patient rejected the manifest refraction when in a trial frame. I conveyed information about the eye disease, including how signif-icant progression was unlikely at his age, as keratoconus is known to arrest on its own by the third to fourth decade of life.10

I recommended prescribing scleral contact lenses for both eyes and he scheduled a diagnostic fi tting visit.

When he returned for diagnostic lens fi tting, I started with Jupiter scleral lenses (Visionary Optics). The following initial lenses were applied with fl uorescein (NaFl):

OD: 7.50mm base curve, -5.00D power, 18.2mm diameter, standard peripheral system.OS: 6.25mm base curve, -14.00D power, 18.2mm diameter, standard peripheral system.

The NaFl pattern OD showed

excessive central bearing. Over-refraction was not performed. OS showed optimal fi tting character-istics with good centration and approximately 250 micron central clearance extending toward the limbus and a scleral landing zone without any noted vascular blanching or edge lift. Spherical overrefraction OS was +1.00DS yielding 20/25.

A new right diagnostic lens with greater sagittal depth was applied with 7.18mm base curve, -7.00D power, 18.2mm diameter and standard peripheral system.

This lens showed an optimal NaFl pattern with slight infero-temporal decentration, approx-imately 250 microns of central clearance and light superonasal touch in the corneal periphery. The scleral landing zone appeared ideal without vasculature blanch-ing or edge lift. Spherical over-re-fraction was -0.25DS yielding 20/25+.

The fi nal scleral lenses had the following parameters:

OD: 7.18mm base curve, -7.25D power, 18.2mm

Fig. 1. Topography showing corneal irregularity, more in the left than right eye.

C A S E R E P O R T


diameter, standard peripheral system, Boston XO Clear with drill dot.OS: 6.25mm base curve, -13.00D power, 18.2mm diameter, standard peripheral system, Boston XO Clear.

Dispensing and Training VisitRoughly two weeks later, I dispensed the scleral lenses and trained him on proper application, removal and lens care.

Contact lens acuity was 20/25+ with a spherical overrefraction of plano DS in each eye. A cursory evaluation using biomicrosco-py showed a contact lens fi tting relationship consistent with what I expected from the previous visit without air bubbles OU. He was cleared to wear his new contact lenses up to full waking hours, if well tolerated, and asked to return for a contact lens progress visit in one to two weeks.

Progress VisitsA week and a half later, he re-turned reporting that both new lenses performed well with excel-lent vision. Comfort in the right eye was excellent, and comfort in the left eye had improved by 90% compared with his previous expe-riences with other modalities. He noted that there was some tolera-ble redness and soreness in the left eye, especially by the end of the day. Wearing time at this visit was four hours.

Contact lens acuity was 20/25+ with a spherical overrefraction of plano DS in each eye. Fluorescein evaluation of the right lens showed slight inferotemporal decentration but an otherwise optimal fi tting relationship with approximately 250 microns of central clearance and relatively even post-lens tear fi lm distribution, but light su-peronasal peripheral touch. The

left lens showed centration with approximately 250 microns of central clearance with a relatively even post-lens tear fi lm extending toward the limbus, but mild pe-ripheral vascular blanching at the nasal scleral landing zone. A new left lens was ordered with identi-cal parameters except the scleral landing curve was changed from 14.50/0.5 to 15.50/0.5.

When he returned to exchange his existing OS scleral lens for the new lens, visual acuity in the eye was 20/25+ with a plano over-refraction. The new lens showed an improved fi tting relationship with reduced nasal peripheral vascular blanching. There was no noticeable decrease in the central clearance. The patient was asked to report back within two weeks in the event there were any bother-some symptoms, but otherwise to return for routine examination in 12 months.

Annual Examination with Contact Lens EvaluationWhen he presented the next year for his routine examination, he reported doing overall quite well wearing scleral contact lenses. However, he noted in the past one to two months the nasal conjuncti-val area of his left eye was red and sore. He stated that it was mostly a cosmetic issue and that on some occasions he would only wear the right scleral lens. Personal health history was unchanged with no regular medication and no known medication allergies.

Contact lens acuity was 20/25 OD with an overrefraction of -0.50D giving 20/25+, and 20/25+ OS with a plano overrefraction OS.

Biomicroscopy showed no changes to the right eye from the previous examination. However, the left eye showed an area nasally

of raised and injected conjunctival tissue, which was interacting with the scleral lens edge (Figure 2).

Another DiagnosisI diagnosed pingueculitis in the left eye related to mechanical inter-action with the nasal edge of the scleral contact lens.

He was scheduled to return for diagnostic contact lens prescribing into a smaller diameter lens in the left eye.

TreatmentWhen he returned for diagnostic fi tting into new scleral lenses, the primary goal was to prescribe a smaller diameter lens in the left eye to reduce the amount of mechanical interaction against the small nasal pinguecula. The new lens design selected for the left eye was the 16.5mm diam-eter ICD scleral lens (Paragon Vision Sciences), as this diagnostic set was available in the offi ce. Concurrently, I re-prescribed the right lens from the Jupiter design into the Europa design (Visionary Optics) which, according to the manufacturer, is an improved design with a larger optic zone, reverse geometry mid-peripheral reverse curve and an enhanced haptic profi le.11

First diagnostic lenses (Europa design OD, ICD design OS):

OD: 7.18mm base curve, -2.50D power, 18.0mm diameter, standard peripheral system.OS: 6.88mm base curve, -5.00D power, 16.5mm diameter, standard peripheral system, 4500 sag.

The right lens showed slight inferotemporal decentration with approximately 250 microns of central clearance with some light superonasal peripheral thinning of the post-lens tear fi lm. The

C A S E R E P O R T


scleral landing zone was optimal. Spherical over-refraction OD was -5.50DS yielding 20/25+. The left lens showed centration and mod-erate central apical bearing. Due to the lack of central clearance, the following diagnostic lens with 300 microns of additional sagittal depth was then applied:

OS: 6.62mm base curve, -8.00D power, 16.5mm diameter, standard peripheral system, sag: 4800 sag.

This new left lens was centered with approximately 150 microns of central clearance and a relative-ly even post-lens tear fi lm extend-ing toward the limbus, with an ideal scleral landing relationship. Spherical overrefraction OS was -2.25 yielding 20/25.

The following contact lenses were ordered (Europa OD, ICD OS):

OD: 7.18mm base curve, -7.75D power, 18.0mm diameter, standard peripheral system, Boston XO Clear.OS: 6.62mm base curve, -10.25D power, 16.5mm diameter, standard peripheral system, 4800 sag, HDS100 Blue.

When he returned for dispensing

of his new scleral lenses, subjec-tively he reported excellent vision and felt that the smaller left lens was already more comfortable.

Visual acuity was 20/25+ OD with a spherical overrefraction of plano DS and 20/25 OS with a spherical overrefraction of +0.50 OS yielding 20/25. Biomicroscopy showed centered lenses with the left lens edge sparing mechanical interaction with the nasal pinguec-ula. Fluorescein evaluation was not performed. He was asked to return in one week for a contact lens progress visit, and to come in wearing his new scleral contacts for at least an hour.

Progress Visit When he returned for his contact lens progress visit, he had been wearing his lenses for three hours and reporting that he was pleased with the new scleral lenses. He estimated that the redness and discomfort in the left eye had resolved by 98% with the smaller diameter scleral lens. For the right eye, there was no appreciable subjective difference in his wearing experience with the new design. Subjective vision was excellent in both eyes, with comfortable wear

for full waking hours.Contact lens visual acuity was

20/25+ OD with spherical over-refraction of plano DS, and 20/25 OS with spherical overrefraction of +0.50 OS yielding 20/25+.

Biomicroscopy showed the left bulbar conjunctiva had signifi -cantly reduced injection and the infl amed nasal pinguecula had subsided in size (Figure 3). There was no signifi cant corneal staining.

Fluorescein evaluation with the right scleral lens showed approx-imately 250 microns of central clearance with a relatively even post-lens tear fi lm extending to the limbal clearance zone. The scleral landing zone was optimal. The left lens showed approximately 150 microns of central clearance, also with an even post-lens tear fi lm extending to the limbal clearance zone. The scleral landing zone was optimal as well.

A new left lens was ordered, accounting for the +0.50 over-refraction, and he was released to routine annual examination following the lens exchange.

D I S C U S S I O N

Pingueculae are the most common conjunctival lesion, occurring in 48% of patients.9 They can mechanically interact with the landing zone of a scleral con-tact lens, leading to redness and discomfort.7,8

Although prescribing topical corticosteroid therapy would quell the infl ammatory component of pingueculitis, it would not elimi-nate the underlying mechanical in-teraction against the conjunctival elevation and could require chron-ic dosing. The risk of chronic cor-ticosteroid therapy, even with the ester-based corticosteroid lotepre-dnol, is the potential for cataract formation and increased IOP.12 For this reason, although suitable as a

Fig. 2. Left eye after removal of

18.2mm diameter scleral lens

showing conjunctival injection,

especially nasally surrounding

pingueculum, and also Charleux’s

sign with retroillumination.

Fig. 3. Left eye showing resolution

of pingueculitis after the patient was

prescribed the new 16.5mm diameter

scleral lens.

C A S E R E P O R T


periodic adjunct, a more sensible approach is modifying the lens to address the root cause of scleral lens–induced pingueculitis.

A review of the literature de-scribes lens-based modifi cations, such as adding an edge notch on the scleral lens to resolve the problems with pingueculae.7,8,14

However, because these edge notches are introduced using a hand tool, there is variability with lens reproducibility. MicroVaults (Alden Optical)—designed and manufactured with CAD/CAM technology—may overcome the problems of reproducibility found with traditional hand-notching, according to the manufacturer. (Figure 4).15 With both hand-notched lenses and MicroVaults, the patient must apply the notches in the proper orientation to cor-respond with the location of the pinguecula.

Finally, although not the case with this patient, hybrid lens-es may afford resolution of the mechanical interaction on the pinguecula due to draping of the soft skirt over the conjunctival elevation.

As illustrated by this case report, ordering a smaller diameter scleral lens was a simple and effective treatment for this patient’s pingue-culitis, particularly because it was peripherally located. The benefi t of decreasing lens diameter is that it is simple, can minimize further cost to the patient, and removes the burden of applying the lens with the notch or MicroVault in the same location of the pinguecu-la. While decreasing diameter may seem an intuitive solution, interest-ingly, another purported strategy is to prescribe an even larger diam-eter scleral lens to compress the pinguecula.13

Scleral contact lenses are very well tolerated by most patients

with keratoconus due to good comfort and vision, especially when compared to corneal gas permeables and other types of contact lenses.6 The high rate of success of scleral lenses should remind clinicians to educate those with keratoconus about the importance of ultraviolet (UV) light protection to minimize the risk of developing pingueculae. Although the aforementioned modifi cations to scleral lenses can help patients with pingueculae to remain in scleral lens wear, it is best if patients never develop these conjunctival lesions in the fi rst place. Although UV light may have a therapeutic effect in miti-gating keratoconus progression by facilitating collagen crosslinking, it is likely outweighed by the risks of UV exposure, including certain eyelid growths, pingueculae, ptery-gia, cataract and retinal damage.16

Scleral contact lenses are well tolerated by most keratoconus

patients, but conjunctival lesions, including pingueculae, can pose an obstacle to success. For some pa-tients, reducing the lens diameter to eliminate or reduce interaction of the lens edge with the conjunc-tival lesion—especially if the lesion is located peripherally—is the sim-plest treatment option. Conversely, for others with pingueculae, enlarging the scleral lens diame-ter to deliberately compress the conjunctival elevation may help. If

these treatments are unsatisfacto-ry, edge notching and MicroVaults are the next logical step, which involves greater complexity due to additional position specifi cation of these lens modifi cations. RCCL

1. Alió JL, Shabayek MH. Corneal higher order aber-rations: a method to grade keratoconus. J Refract Surg. 2006;22(6):539-45.2. Barnett M, Mannis MJ. Contact lenses in the man-agement of keratoconus. Cornea. 2011;30(12):1510-6.3. Schornack MM, Patel SV. Scleral lenses in the management of keratoconus. Eye Contact Lens. 2010;36(1):39-44.4. Van der Worp E, Bornman D, Ferreira DL, et al. Modern scleral contact lenses: A review. Cont Lens Anterior Eye. 2014;37(4):240-50.5. Visser ES, Visser R, van Lier HJ, et al. Modern scleral lenses part II: patient satisfaction. Eye Con-tact Lens. 2007;31(1):21-5.6. Bergmanson JPG, Walker MK, Johnson LA. Assessing scleral contact lens satisfaction in a kera-toconus population. Optom Vis Sci. 2016;93(8[Epub ahead of print].7. Messer M. Getting creative with scleral lenses: Part 1. Review of Cornea & Contact Lenses. 2012;148(1):7. 8. Denaeyer GW. Designing lenses to work around scleral obstacles. Contact Lens Spectrum. August 2012. Available at www.clspectrum.com/articleview-er.aspx?articleID=107286. Accessed May 24, 2016.9. Viso E, Gude F, Rodríguez-Ares MT. Prevalence of pinguecula and pterygium in a general population in Spain. Eye (Lond). 2011;25(3):350-7.10. Rabinowitz YS. Keratoconus. Surv. of Ophthal-mol. 1998;42:297–319.11. Visionary Optics. Europa Scleral Overview. Available at www.visionary-optics.com/products/scleral-lens-for-irregular-corneas/europa-scleral. Accessed May 30, 2026. 12. Comston TL, DeCory HH. Advances in cortico-steroid therapy for ocular infl ammation: loteprednol etabonate. Int J Infl am. 2012;2012:789623.13. Barnett M. Case study: scleral lenses post glauco-ma surgery. Optometric Management. December 1, 2014. Available at www.optometricmanagement.com/articleviewer.aspx?articleID=112072. Accessed May 24, 2016. 14. Messer B. Utilizing MicroVaults to improve comfort and cosmesis in scleral lens wearers with pingueculae. Poster. Available at www.aldenoptical.com/docs/zenlens/Zenlens_Poster.pdf. Accessed May 24, 2016. 15. Van der Worp E. A guide to scleral lens fi tting, Version 2.0 [monograph online]. Forest Grove, OR: Pacifi c University; 2015:51. Available from: http://commons.pacifi cu.edu/mono/10/. 16. Behar-Cohen F, Baillet G, de Ayguavives T, et al. Ultraviolet damage to the eye revisited: eye-sun pro-tection factor (E-SPF®), a new ultraviolet protection label for eyewear. Clin Ophthalmol. 2014;8:87-104.

Fig. 4. Just like scleral lenses with an edge notch, MicroVault lenses require

lens application with rotational registration such that the MicroVault aligns

with the conjunctival elevation.

Photo: A

lden Optical


Dry eye disease (DED) is a massive but often under-appreciated problem. Data sug-gests as many as 35%

of Americans have some degree of DED.1,2 While there is a surfeit of information on DED treatment, diagnosis and observation seem to be the more challenging aspects.

The ocular tear fi lm is often observed, but rarely qualifi ed. This qualifi cation is one of the most challenging parts of man-aging DED. The ocular tear fi lm provides lubrication and visual clarity and is also the fi rst barrier of protection for our eyes. Any ve-hicle is markedly limited without a windshield, but if the windshield it has is covered in dirt or mud, it is useless.

Knowing the anatomical char-acteristics of the tear fi lm builds the framework for a better under-standing of ocular surface disease.

TEAR FILM ANATOMY:

A REFRESHER

All clinicians know that the tear fi lm is comprised of three dynamic layers—mucin, aqueous and lip-id—but some of its specifi cs may elude us in routine practice. The mucin layer is 0.02µm to 0.05µm thick and provides an anchor for tear fi lm foundation, while the aqueous layer resides between both mucin and lipid layers and is the thickest layer, at 0.7µm. The most superfi cial is the lipid layer, which helps protect the tear fi lm

from decomposition.3

Tears are produced from the lacrimal gland under the infl uence of the parasympathetic and sym-pathetic nervous system.4 Through dynamic tear fi lm interferometry we know tear fl uid is spread over the ocular surface from tempo-ral to the nasal segments of the eye.5,6 The distribution of tears is dependent on lid blink, and facilitation of drainage is through the lacrimal puncta.5,7 The tear fi lm takes one of three outputs: evaporation, drainage or absorp-tion. Evaporation is inevitable, but accelerated by poor lipid tear layer.8 Drainage through the na-solacrimal system can be impeded by anatomical morphology such as scarring or cautery. Absorption is suggested through corneal per-meability in the absence of com-promised corneal function and is reported as minimal, roughly 15% absorption.9,10

Collectively, the tear fi lm supplies the ocular surface with many nutrients and wound healing properties such as fi bronectin, vitamins and growth factors.11

These elements support and modu-late proliferation, migration and differentiation of the conjunctival and corneal epithelium.

AQUEOUS-DEFICIENT VS.

EVAPORATIVE DED

The Dry Eye Workshop defi ned two modalities of DED: aqueous defi cient and evaporative.12 Of these two subcategories, evapora-

tive dry eye represents the major-ity of cases.13,14 Evaporative dry eye disease, which results from increased ocular surface exposure and meibomian gland dysfunction (MGD), is commonly associated with an infl ammatory process.12

During infl ammation, proteins are released into the tears, which serve to support opsonization (i.e., targeting) and phagocytosis of microbes by macrophages and lymphocytes. Ultimately, damage to the meibomian or sebaceous glands comes from androgen dys-regulation, microbe invasion and excretory duct obstruction due to hyperkeratinization and increased viscosity of meibum.15,16 Tears serve a lubricating and mechanical clearance function, but also pos-sess epitheliotropic and antimicro-bial properties.17,18

The importance of identifying these underlying processes and how they contribute to tear fi lm

ABOUT THE AUTHOR

Dr. Smith is an optometric

physician with a special

interest in dry eye

management, therapeutic

contact lenses and surgical

comanagement. Currently,

he practices at the Veterans

Aff airs outpatient clinic in

Jacksonville, VA, where there is

great demand for emergency eye care and

management of chronic ocular disease. Dr.

Smith has served as a board member and

volunteer for many organizations, including:

Volunteer Optometric Services to Humanity

(VOSH), Jeff erson County Community

Participation Board and Equal Access

Birmingham. He is a member of Florida

Optometric Association and American

Optometric Association and is a National

Association of Veterans Aff airs optometrist.

Advances in Understanding

Tear Film DynamicsLet’s gain some perspective on the components, modalities and methodology of dry eye.

By Will Smith, OD


ADVANCES IN UNDERSTANDING TEAR FILM DYNAMICS

dysfunction cannot be overstated. Diagnostic tools have advanced to allow proper quality assessment of tear fi lm dynamics, and they help to standardize a protocol for diagnosis and management.

OBSERVING THE GLANDS

Meibomian gland observation can be performed by meiboscopy, interferometry and meibography.

Meiboscopy is performed with basic transillumination of the lids (Figure 1).20 Although this method is quick, effective and available to all practitioners, newer techniques and tools provide better visualiza-tion of meibomian gland structure.

Meibography allows for the evaluation of the number and morphology of the meibomian glands from their point of origin through to the ductal termination at the orifi ces (Figure 2). There are two principles in meibography: transillumination of the evert-ed lid and direct illumination, or non-contact meibography. Slit-lamp microscopy (Topcon), portable noncontact meibogra-phy (Shenzhen LYD Technology), LipiScan (TearScience), LipiView II (TearScience) and Keratography 5M (Oculus) are all instruments designed to perform meibography.

Only gross imaging scales exist for grading at this time (Figure 3).21 Although rudimentary, they are effective in documenting baseline meibomian status by

comparing the patient’s gland structure with the closest associat-ed grading. Studies show methods of grading meibography images demonstrate good within-reader reliability and fair between-read-er reliability.22 Researchers ob-served normal aging changes of meibomian glands such as acinar (glandular) density reduction and an evident decrease of the acinar diameter without signifi cant mod-ifi cations of the glandular orifi ce diameter.23 They also observed morphological changes in disease states; with MGD, acinar density was reduced but diameter was in-creased, and orifi ce diameter was dilated.23

Interferometry allows for micro observation of the tear fi lm’s lipid layer. Basic optical theory of re-fl ectance and thin fi lm interferom-etry can indicate the hue and sat-uration seen as a function of the thickness of the transparent layer, causing the interference phenom-ena.24 Lipiview II (TearScience) is the only commercial instrument designed to provide real-time visu-alization of the lipid layer thick-ness, lid closure and blink rate with one scan. Research shows a thin lipid layer correlates with dry eye disease symptoms.25

HYPEROSMOLARITY

Tear fi lm hyperosmolarity is con-sidered by some researchers to be the primary cause of discomfort,

ocular surface damage and infl am-mation in dry eye.26 Osmolarity can be measured with TearLab’s handheld osmometer. A clinical cut-off of 312mOsm is suggested as the diagnostic level for aque-ous-defi cient and evaporative dry eye.27 Any decrease in meibum or aqueous secretion contributes to increases in osmolarity, thus com-plicating diagnostic specifi city.

Researchers evaluated whether tear fi lm osmolarity could be used as a reliable diagnostic tool for dry eye in patients with rheuma-toid arthritis (RA). They found that 66% of patients with RA have osmolarity of greater than 316mOsm, serving as an indi-cation for work-up of systemic infl ammatory diseases.28

Matrix metalloproteinase-9 (MMP-9)—a nonspecifi c marker of infl ammation—is a proteo-lytic enzyme that comes from stressed epithelial cells on the ocular surface.29 In healthy control individuals, MMP-9 is normally found at low levels; however, in those with DED, levels rise to more than 40ng/ml.29,30 MMP-9 can be measured by Infl ammaDry (Rapid Pathogen Screening, RPS). To perform this point-of-care test, swab the palpebral conjunctiva, and place the swab into the RPS

Fig. 1. Transillumination of lower lid, showing meibomian gland structure with

blue and white arrows.

Fig. 2. Meibography of normal gland

structure (top) and gland truncation

or scarring (bottom).


cassette, where a buffer is applied to complete the test.

Although eye care practitioners have long been able to identify dry eye patients by clinical observa-tion of ocular surface disruption, osmolarity and MMP-9 testing—particularly when used in combi-nation—increase the precision we can bring to our assessment and management plan.

STANDARDIZED PROTOCOL

Diagnostic technologies still lack the ability to determine the ideal course of disease management—that remains a clinical responsibil-ity. As providers, we seek certainty to provide the most targeted and cost effective care. Not all technol-ogies provide equal value, but all increase our knowledge.

The best strategy with DED testing is to keep follow-up care consistent with a standardized protocol (Figure 4) that provides information about tear produc-tion, ocular surface grade and meibomian gland function. RCCL

1. Improving screening, Diagnosis, And Treatment of Dry Eye Disease: Expert Recommendations From the 2014 Dry Eye Summit. National Eye Institute. Facts about dry eye. Availabe at www.nei.nih.gov/health/dryeye/dryeye. Accessed September 7, 2016.2. The Epidemiology of Dry Eye Disease: Report of the Epidemiology Subcommittee of the Inter-national Dry Eye WorkShop. 2007;5(2):93-107.3. Creech J, Do L, Ratt I, Radke C. In vivo tear fi lm thickness and implications for tear fi lm sta-bility. Curr Eye Res. 1998 Nov;(11):1058-66.

4. Dartt DA. Dysfunctional neural regulation of lacrimal gland secretion and its role in the pathogenesis of dry eye syndromes. The Ocular Surface. 2004;2:76-88.5. Clinch TE, Benedetto DA, Felberg NT, Laibson PR. Schirmer’s test. A closer look. Arch Ophthal-mol. 1983;101:1383-6.6. Doane MG. An instrument for in vivo tear fi lm interferometry. Optom Vis Sci. 1989;66:383-8.7. Tsubota K. Tear dynamics and dry eye. Prog Retin Eye Res. 1998;17:565-96.8. Lozato PA, Pisella PJ, Baudouin C. The lipid layer of the lacrimal tear fi lm: physiology and pathology. J Fr Ophtalmol. 2001;24(6):643-58.9. Joshi A, Maurice DM, Paugh JR. A new method for determining corneal epithelial barrier to fl uorescein in humans. Invest Ophthalmol Vis Sci. 1996;37:1008-16.10. Goebbels M, Spitznas M. Corneal epithe-lial permeability of dry eyes before and after treatment with artifi cial tears. Ophthalmology. 1992;99:873-8.11. Geerling G, MacLennan S, Hartwig D. Autol-ogous serum eyedrops for ocular surface disor-ders. Br J Ophthalmol. 2004;88(11):1467–74.12. The defi nition and classifi cation of dry eye disease: report of the Defi nition and classifi ca-tion Subcommitee of the International Dry Eye WorkShop. Ocul Surf. 2007;5(2):75-92.13. Shimazaki J, Sakata M, Tsubota D. Ocular surface changes and discomfort in patients with Meibomian gland dysfunction. Arch Ophthalmol. 1995;113:1266-70.

14. Lemp M, Crews L, Ron A, et al. Distribution of aqueous defi cient and evaporative dry eye in a clinic-based patient population. Cornea. 2012 May;31(5):472-8.15. Gilbard JP. The diagnosis and management of dry eyes. Otolargngol Clin N Am. 2005;38;5:871-85.16. Thody AJ, Shuster S. Control and function of sebaceous glands. Physiol Rev. 1989;69:383-416.17. Sullivan D, Sullivan BD, Ullman MD, et al. An-drogen infl uence on the meibomian gland. Invest Ophthalmol Vis Sci. 2000;41:3732-42.18. Ng V, Cho P, Mak S, Lee A. Variability of tear protein levels in normal young adults: between-day variation. Graefes Arch Clin Exp Ophthalmol. 2000;238:892–9.19. Liu S, Richards S, Lo K, et al. Changes in gene expression in human meibomian gland dysfunc-tion. Inv Ophthmol Vis Sci. 2011;52:272-4.20. Tapie R. Etude biomicroscopique des glandes de meibomius. Ann Oculistique. 1977;210:637–48.21. Pult H, Riede-Pult B. Neues zur Meibographie. Die Kontaktlinse. 2011;6:24–5.22. Nichols JJ, Berntsen DA, Mitchell GL, Nichols KK. An assessment of grading scales for meibog-raphy images. Cornea. 2005;24:382–8.23. Fasanella V, Agnifi li L, Mastropasqua R, et al. In vivo laser scanning confocal microscopy of human meibomian glands in aging and ocular surface diseases. Biomed Res Int. 2016;7432131.24. Doane M, Lee E. Tear fi lm interferometry as a diagnostic tool for evaluating normal and dry-eye tear fi lm. In: Lacrimal gland, tear fi lm, and dry eye syndromes 2. 1998;438:297-303.25. Tomlinson A, Khanai S. Assessment of tear fi lm dynamics: quanifi cation approach. 2005;3(2):81-95.26. Blackie CA, Solomon JD, Scaffi di RC, et al. The relationship between dry eye symptoms and lipid layer thickness. Cornea. 2009;28(7):789-94.27. Gilbard JP, Farris RL, Santamaria J 2nd. Oso-molarity of tear microvolumes in keratoconjunc-tivitis sicca. Arch Ophthalmol. 1978;96:688-91.28. Schargus M, Wolf F, Tony H, et al. Correlation between tear fi lm osmolarity, dry eye disease, and rheumatoid arthritis. Cornea. 2014;33:1257-61.29. Chotikavanich S, de Paiva CS, Li de Q, et al. Production and activity of MMP-9 on the ocular surface increase in DTS. Invest Ophthalmol Vis Sci. 2009;50:3203-9.

30. Acera A, Rocha G, Vecino E, et al. Infl amma-tory markers in the tears of patients with OSD. Ophthalmic Res. 2008;40:315-21.

Questionnaire Interferometry Osmolarity(TearLab)

InflammaDry(RPS)

Slit LampExam

(Careful lidevaluation)

Meibography Schirmer's Staining

Fig 4. Example of an ocular surface work-up protocol.

Fig. 3. Five-grade meiboscale.14

© 2012, 2016 Dr. Heiko Pult — Optometry & Vision Research, Germany,

www.heiko-pult-de, used with permission.

Meiboscale Area of Loss


By Mile Brujic, OD, and Jason Miller, OD, MBA

Practice Progress

While new technology is exciting at fi rst glance, it often fails

to make a lasting impact in our practices. Many of us forget about new technological advancements, falling back into our comfort zone, particularly with contact lens fi ts. But early adopters to change will develop the culture of “being ahead of the curve” and reap the rewards of increased revenue for that technology.

Many of us have heard the phrase, “if it’s not broke, don’t fi x it.” While that holds true for some scenarios, it’s not always the smartest approach to contact lens fi tting. It’s worth taking a broad-er perspective that incorporates technological advancement when addressing certain contact lens situations. You may fi nd a better way of doing things. This month,

we look at two cases and discuss ways to break some habits many of us may have developed over time—regardless of effi cacy.

CASE 1: CHILDREN AND

CONTACT LENSES

A 10-year-old male patient wants to start wearing contact lenses. His myopic correction has just jumped from a -1.00DS OU to a -2.00DS OU in the past eight months.

Old habits. The most familiar method for this case would be to discuss the various options of contact lenses—from dailies to the reusable two-week or one-month modalities. After that discussion, let the parents decide what they think would work best for their child. Without any information on the differences between CLs, most patients would choose the least costly modality.

New habits. If, on the other hand, we incorporate a broader

perspective and take into account the current state of technology, we would start with making a strong recommendation for the new, innovative daily disposable lenses. Research demonstrates that three in fi ve contact lens wearers do not wash their hands prior to han-dling the lenses.1 The minimized handling that comes with daily disposable lenses is just one reason they are the healthiest and most convenient choice and are now considered the lens of choice for this younger population.

Next, consider taking a step further to discuss contact lenses for myopia control. It is proving worth our time to educate pa-tients (or their parents) on certain contact lens options now available that are benefi cial for slowing refractive changes at a young age. Myopia control contact lenses offer much promise and may be the next big thing in the contact lens industry.

This area is one of untapped potential and could form the foun-dation for future treatments for children with developing myopia. Many studies are currently looking at the possibilities, but if we could tell parents they could reduce their child’s vision impairment by a cer-tain percentage (working toward a design or treatment that would reduce myopia by 50%), that would be a drastic improvement worth exploring.

These lenses work by slowing down the patient’s predicted axial length elongation. Through a com-plicated process, the peripheral retina can mediate refractive devel-opment centrally. The peripheral

Remain current with technological advancement so your patients and practices can thrive.

Breaking Habits

End-of-day dryness and limbal injection from signifi cant digital device use

demonstrates signs of contact lens-related complications.


hyperopia can be a stimulus and may even precede the development of myopia. Current theories are aimed at preventing this peripheral defocus at an early age.2 Questions obviously remain, but many re-searchers are evaluating the role of genetic predisposition, amount of near work, lag of accommodation, vitamin D levels and the amount of time spent outdoors.3,4

Other new treatments such as light fi ltering spectacle lenses, soft or rigid bifocal or multifocal contact lenses, orthokeratology lenses and pharmaceutical agents (atropine, pirenzepine, 7-meth-ylxanthine) are under thorough evaluation.

As eye care professionals, we see similar cases on a daily basis. Having the tools, technology and research to back up our recom-mendations is critical. Don’t get stuck in the same old habits or wait too long.

CASE 2: DIGITAL

DEVICE USER

A 30-year-old female patient is currently wearing monthly dispos-able contact lenses and wants to

renew her contact lens prescrip-tion. She says she is happy with her current lenses.

Old habits. The most familiar route would consist of performing the examination, checking the patient’s refraction and renewing the same prescription. Rather than trying to upgrade the patient into a newer contact lens technolo-gy, it is often quicker and easier to just renew the prescription if everything looks up to par and the patient has no complaints. This is, unfortunately, the more common approach in many offi ces.

New habits. If we want to remain ahead of the curve and consider the best option available to us, we should start by getting the whole story. Upon further questioning, you fi nd out that this patient works at a bank and spends eight to 10 hours a day on the computer. She has intermittent blurriness (due to a reduced blink rate and incomplete blinking) throughout the day and her eyes look red at the end of the day. The general consensus, after a more thorough session, would be that our patient’s current contact lens regimen is not, in fact, good at all.

As a result of extensive digi-tal device use, today’s patients put new visual health demands on their eyes. Despite all of the advances in contact lens technol-ogy, patient discomfort remains a problem. Many are reticent to complain and would rather contin-ue with what they have than deal with alternatives. Patients often imagine the worst, and so avoid confronting the idea of change. This case provides a great oppor-

tunity to upgrade the patient into more technologically advanced contact lenses. Patients need a con-tact lens that can provide all-day visual clarity and comfort.

Instead of providing the same contact lens prescription, consider refi tting this patient in a newer design and modality. Many new daily disposable contact lenses have moisture agents embedded in the matrix of the contact lens to help reduce end-of-day dryness and improve all-day comfort. Additionally, consider using a lens that provides improved optical correction while on the computer. This may be an aspheric or a low multifocal design to help with the accommodative demand through-out the day.

Eye care professionals can choose from a wide variety

of contact lens materials, designs and modalities that can improve ocular health and visual clarity. Innovative products and research will continue to drive the market. It is vital we stay current with ongoing research in an attempt to break old habits and integrate new and improved methodologies into our practices—a shift that is sure to provide improved health to our patients and growth to our practices. RCCL

1. Stone R. The importance of compliance: focusing on the key steps. Poster presented at the annual meeting of the British Contact Lens Association; May 31-June 2, 2007.2. Mutti DO, Sholtz RI, Friedman NE, Zadnik K. Peripheral refraction and ocular shape in children. Invest Ophthalmol Vis Sci. 2000:41(5):1022-30.3. Mutti DO, Marks AR. Blood levels of vitamin D in teens and young adults with myopia. Optom Vis Sci. 2011;88:377-82. 4. Mutti DO, Mitchell GL, Sinnott LT, et al. Corneal and crystalline lens dimensions before and after myopia onset. Optom Vis Sci. 2012;89:251-62.

Dryness from incomplete blinks can

happen at any age, especially for

digital device users.

Photo: P

aul M. K

arpecki, OD

By Gary Gerber, OD

Out of the Box


Four Keys to Building Your PracticeThese commonalities indicate you are ready to venture out on your own—and that you will be successful when you do.

Over the last few years, our consulting com-pany has helped an array of doctors start their own practices.

Many are transitioning from corpo-rate to private practice, while others are working for ODs and are now ready to venture out on their own. Looking back on these practices and seeing what they did to become successful made me realize they all had four things in common:

1. BUILD A STRONG BRAND

They know who they are and what they want. More specifi cally, they have a strong brand, mission and

values. These practices unequivo-cally stand for something. They are known in their communities for do-ing one particular thing better than other practices. That one thing may be clinical (specialty contact lenses, dry eye treatment or pediatrics) or experiential (exemplary, memorable service; unique optical selection; strong involvement in the commu-nity). Notably, they are willing to perform this métier to the exclusion of others. For example, specialty lens practices de-emphasize eyeglass offerings to increase referrals from other practitioners, and pediatric practices don’t see adults. Unique

optical providers offer frames not readily found elsewhere, making the buying experience distinctive.

2. BECOME A GREAT LEADER

These doctors are great leaders. Many are naturals, but most aren’t. Rather, most became great leaders by staying hyper-focused on their brands to ensure every employee is keyed in to the specifi c nature of the practice. So, instead of just holding a staff meeting and saying, “We are going to change the way we book appointments from Y to Z,” they use this as a brand teaching mo-ment: “Because our brand is about X, and because every decision and

fi ber of this practice involves some component of X, we are changing the way we book appointments from Y to Z.” When staff members overhear these leaders talking to pa-tients, sales reps, family or friends, the brand messaging is infused in every conversation. They set an example of what it means to live the brand. From that, their staff sees an unwavering commitment to the practice brand and values, which results in a staff that wants to be a part of something meaningful.

3. WELCOME CHANGE

Change is welcomed, encouraged

and happens quickly. Staff members are constantly challenged to offer suggestions on how to improve the brand. Even though most of these practices open their doors with only one staff member, that person isn’t simply a robot tasked with answering the phones and verify-ing insurance claims. Rather, they are a source of new ideas—which are always solicited and genuinely welcomed. If that person rarely has new ideas, they are quickly replaced. While training new staff is never an easy task, it’s usually easier for new practices because of the extra time available. Smart owners use this downtime to train staff on technical aspects of their own culture and brands.

4. AVOID BUREAUCRACY

As these practices grow, they do so with the mindful intent of avoiding an impenetrable bureaucracy. The owner creates a culture in which they are always an approachable, brand-savvy CEO without adding barriers and layers of documents and policies that would stunt growth. There are fewer depart-ments and managers in these prac-tices than others, and their teams work better together without the stifl ing corporate structure.

These four characteristics mark successful transitions into pri-

vate practice. Reviewing them can shed light for other ODs wishing to branch out into their own prac-tice. Get focused, employ a team invested in your brand and remain approachable—then watch your practice thrive. RCCL

GET FOCUSED, EMPLOY A TEAM INVESTED IN YOUR BRAND AND REMAIN APPROACHABLE—THEN WATCH YOUR PRACTICE THRIVE.

*When the ECP followed the fitting guide for the 3-Zone Progressive™ Design of PureVision®2 for Presbyopia lens.

REFERENCES: 1. Data on file. Bausch & Lomb Incorporated. Rochester, NY; 2013. 2. Data on file. Bausch & Lomb Incorporated. Rochester,

NY; 2015. 3. Thirty-nine ECPs (from 10 countries) refitted 422 existing soft contact lens wearing presbyopes into PureVision®2 Presbyopia

lenses. Patients returned for follow-up visits after 1-2 weeks. ECP assessment of lens performance including ease of fit, and patient satisfaction

with lenses in real-world conditions, were measured using a 6-point agreement survey.

Bausch + Lomb ULTRA, MoistureSeal, PureVision, and 3-Zone Progressive are trademarks of Bausch & Lomb Incorporated or its affiliates.

©2016 Bausch & Lomb Incorporated. UFP.0146.USA.16

INTTRROOODDUUCCINGG

Exceptional comfort unites with

a proven multifocal design

Provide your patients

clarity through consistencyLearn more at www.Bausch.com/UFP

MoistureSeal® technology

• Helps maintain 95% of lens moisture for a full 16 hours1

3-Zone Progressive™ Design

• Provides outstanding near, intermediate, and distance vision2

• Offers easy, predictable fitting where 80% of patients were successfully fit in one visit2,3*

Bausch + Lomb ULTRA®

for Presbyopia

RO0516_B & L Ultra.indd 1 4/25/16 11:45 AM

The most comprehensiveGP lens care system available.

Menicon LacriPure joins Menicon Unique pH® multi-purpose solution and Menicon PROGENT protein remover to complete the industry’s most comprehensive GP lens care system.

800-636-4266 | meniconamerica.com | [email protected]

Introducing LacriPureMenicon’s new rinsing and insertion saline solution.

Indicated for use with soft, hybrid and rigid gas permeable lenses,LacriPure is a sterile, non-preserved saline which provides an alternative to tap water rinsing.

Packaged in a 5ml unit-dose vial, LacriPure has been cleared as a scleral lens insertion solution and provides the patient with exceptional sterility.

RCCL0416_Menicon.indd 1 3/22/16 3:33 PM

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