rccl - review of cornea and contact lenses · in lens cases rather than using new solution (55.1%)....

Supplement to

RCCLRCCLREVIEW OF CORNEA & CONTACT LENSES

to Improve Scleral Lens Fittingto Improve Scleral Lens Fitting

Are You Making Good Use of Your Diagnostic

Fitting Sets?

Gas Permeables

One Size Does Not Fit All

Custom Contact Lenses in 2015

Making the Case for Custom Lenses

Options Abound!

EARN 1 CE CREDIT

SEPTEMBER 2015SEPTEMBER 2015

SPECIAL ISSUE:

CUSTOM LENSESCUSTOM LENSES

001_RCCL0915_cover.indd 1001_RCCL0915_cover.indd 1 8/25/15 12:47 PM8/25/15 12:47 PM

aldenoptical.com | 800.253.3669 | [email protected]

* Please add 2-3 days for prosthetics and enhancement tints. Alden Optical, ASTERA, EZ-Exchange, NovaKone, and Zenlens are trademarks or registered trademarks of Alden Optical Laboratories.

+ + + + + + + ++ + + + + + + ++ + + + + + + ++ + + + + + + ++ + + + + + + + + + + + + + + +

A Successful Specialty Contact Lens Practice Starts With An Experienced

Specialty Lens Partner

If you want fitting specialty lenses to be a great experience, demand a partner that has great experience. Alden Optical® has been making outstanding specialty lenses for over

45 years. Just as important, our team has a combined 324 years of contact lens experience—

a remarkable average of 18 years per employee.

From lenses designed to ensure great success, to service and support that intuitively meet

your needs, to a small company ethos that knows and empathizes with your challenges,

partnering with Alden Optical is an experience that delivers unparalleled value.

• Every single lens is backed by our exclusive 90-day EZ-Exchange™ warranty, including

full cancellation privileges—even on Zenlens™

• All lenses manufactured in three days* or less

• Expert consultation and customer service

HP Toric & Sphere Fit virtually any astigmat

ASTERA® Multifocal Toric Fit your presbyopic astigmats

Zenlens™ The enlightened scleral

NovaKone® Simplified fitting for you, comfort

and acuity for your patients

RCCL0915_Alden.indd 1RCCL0915_Alden.indd 1 8/19/15 10:25 AM8/19/15 10:25 AM

contentsReview of Cornea & Contact Lenses | September 2015

/ReviewofCorneaAndContactLenses #rcclmag

departments

12Making the Case for Custom Lenses Finding a lens for every patient can boost your practice and your profi ts.By Robert Ensley, OD

16GPs: Are You Making Good Use of Diagnostic Fitting Sets?An expert walks you through the fi ner points of the process to help you achieve better results.By Joel A. Silbert, OD, FAAO

News Review4CDC Report Notes Widespread

Lens Care Noncompliance

My Perspective 6The Myopia Menace

By Joseph P. Shovlin, OD

Pharma Science & Practice8 Pregnant Pause

By Elyse L. Chaglasian, OD, and Tammy Than, MS, OD

Meet the Candidates

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

The GP Expert32

Practice Progress 10

A Lens for Every Eye:

Custom Contact Lenses

By Stephanie L. Woo, OD

features

Blinded by the Light?

By Gary Gerber, OD

Out of the Box34

Cover design by Matt Egger©iStock.com/Jobsonhealthcare

REVIEW OF CORNEA & CONTACT LENSES | SEPTEMBER 2015 3

26CE — Critical Measurements to Improve Scleral Lens FittingGathering as much data as possible can help streamline the process and provide better outcomes.By Jason Jedlicka, OD

features

22Options Abound: A 2015 Report on Custom Contact LensesKeep abreast of new lens developments and related technology that can strengthen your practice.By Edward S. Bennett, OD

003_RCCL0915_TOC.indd 3003_RCCL0915_TOC.indd 3 8/25/15 10:23 AM8/25/15 10:23 AM

News Review

4 REVIEW OF CORNEA & CONTACT LENSES | SEPTEMBER 2015

IN BRIEF• Certain cosmetic products may have a signifi cant adverse eff ect on contact

lens shape, wettability and optical

performance, report studies published in the July 2015 Eye & Contact Lens.1,2 Researchers in Canada coated seven silicone hydrogel lens materials with nine marketed brands of cosmetics: three hand creams, three eye makeup removers and three mascaras.

Makeup removers were found to have the greatest impact on lens diameter, sagittal depth and base curve, while mascaras were most detrimental to optical performance and wettability. The researchers note that in some cases the eff ects were irreversible despite lens cleaning, and suggest further clinical studies are needed on the impact of cosmetics on silicone hydrogel lenses.

1. Luensmann D, Yu Mili, Yang J, et al. Impact of cosmetics on the physical dimension and optical performance of silicone hydrogel contact lenses. Eye & Contact Lens. 2015 Jul;41(4):218-227.

2. Srinivasan S, Otchere H, Yu Mili, et al. Impact of cosmetics on the surface properties of silicone hydrogel contact lenses. Eye & Contact Lens. 2015 Jul;41(4):228-235.

• Patients with good unilateral visual acuity may be better candidates for a

Boston keratoprosthesis (BKPro) im-plant than previously believed, reports a study in the September 2015 Cornea.1 Previously, implantation was only con-sidered for patients with severe bilateral visual impairment, due to long-term risk and low expectations.

In a retrospective analysis of 37 BKPro patients (28 for failed PK, nine primary BKPro implants) with pre-op

BCVA of 20/40 or better and mean follow-up of 31.7 months, the most common complications were elevated IOP and retroprosthetic membrane formation. Ultimately, the researchers reported, half of patients achieved the

minimum VA required for binocular

functioning, with one-third achiev-ing BCVA similar to the contralateral healthy eye.1. Mustafa K, Kunal S, Rapuano J, et al. Long-term results of the boston keratoprosthesis for unilat-eral corneal disease. Cornea. 2015 Sep;34(9):1057-1062.

One in six US adults wears contact lenses, and virtually all engage in some form of

risky behavior concerning lens care. Those are a few highlights of a new report from the US Centers for Dis-ease Control (CDC) on contact lens wearer demographics and behavioral infl uences on risk of contact lens-related eye infection, part of the or-ganization’s Morbidity and Mortality Weekly Report.1

The population-based study identi-fi ed 40.9 million contact lens wearers (i.e., one sixth of the adult popu-lation) in the country, with 93% wearing soft contact lenses. Of the total respondents, most were white (64.5%) females (60.7%) aged 30-39 (24.8%) from the South (37.1%) with a high school level of education (31.5%) who live in metropolitan areas (87.1%). The study did not consider lens wearers under age 18.

A subset of the contact lens-wearing population (n=1,000) also completed the CDC’s Contact Lens Risk Survey. Roughly 99% of the respondents reported at least one contact lens hygiene risk behavior associated with an increased risk for eye infection or infl ammation. These include:

• Exposing lenses to potential water-borne contamination, either

by swimming (61%), showering (84.9%) or rinsing them in tap water (35.5%).

• Sleeping (50.2%) or napping (87.1%) in their contact lenses.

• Topping off disinfecting solution in lens cases rather than using new solution (55.1%).

• Not complying with lens (49.9%) or lens case (82.3%) re-placement schedules.

“This population-based study ad-mirably highlights the importance of proper lens hygiene,” says Joseph P. Shovlin, OD, a member of the CDC’s advisory panel. “There are many steps to compliance in caring for lenses; unfortunately, risky behavior remains a major risk for potentially sight-threatening experiences.”

The organization also undertook its second annual Contact Lens Health Week in late August to ad-dress these defi cits in public knowl-edge of lens care. “The Contact Lens Health Week will help deliver the much-needed reminder to lens wear-ers that contact lenses are a medical device,” Dr. Shovlin says. “The mes-sage will undoubtedly help promote safe and effective lens wear.”

1. Cope JR, MD, Collier SA, Rao MM, et al. Contact lens wearer demographics and risk behaviors for contact lens-related eye Infections — United States, 2014. MMWR, Vol. 64(32):865-70. Aug. 21, 2015.

CDC Report Notes Widespread

Lens Care Noncompliance

Advertiser Index

Alden Optical ............................ Cover 2

Bausch + Lomb ...................... Page 5, 21

CooperVision ................Page 7, Cover 3

Hydrogel Vision ......................... Page 19

Menicon ...................................... Cover 4

Study Links CL Wear with Increased MGD Risk

Contact lens wearers, especially those who have worn lenses long-term, may be at increased risk for meibomian gland dysfunction (MGD), reports a study in the September 2015 Cornea. Researchers evaluated the meibomian gland health of 41 daily soft lens wearers vs. 31 age-matched non-lens wearers, using measurements of meibum expressiv-ity and lid margin abnormality. Ultimately, the study conceded an incomplete under-standing of the causative nature of the relationship, but found that contact lens use is re-sponsible for early MGD and that wearers often do not exhibit symptoms severe enough to warrant a typical clinical exam. They hope that more routine examinations of lens wearers can reveal signs of MGD, which can be resolved using prophylactic modalities. 1. Machalińska A, Zakrzewska A, Adamek B, et al. Comparison of morphological and functional meibomian gland characteristics between daily contact lens wearers and nonwearers. Cornea. 2015 Sep;34(9):1098-104.

004_rccl0915_news.indd 4004_rccl0915_news.indd 4 8/25/15 12:48 PM8/25/15 12:48 PM

Go Ahead—Rock the Boat!Steering a course toward technology and comfort with the

Bausch + Lomb ULTRA® contact lens

ByAndrew Paik, ODTarget OpticalChicago, Illinois

In fi tting contact lens patients, it’s easy to fall into the habit of “not rocking the boat.” If a patient is happy in their

contact lenses, it oft en seems expeditious just to leave them in a lens that they al-ready like, without necessarily doing too much critical thinking. By doing this, are we missing an opportunity to off er our patients the latest in contact lens tech-nology, which is a focus for many of us in clinical practice?

One trend in the industry over the last several years has been a shift toward daily disposable lenses. In my own practice, we typically recommended daily dispos-able lenses to most of our contact lens patients, including patients who were non-compliant in bi-monthly modalities. In the past, for patients who were happy in their current monthly lenses, we would try to keep them in those lenses or else recommend a daily disposable. All of that changed with introduction of the Bausch + Lomb ULTRA® contact lens, which really has all of the features that we’re looking for in a single lens – aspher-ic optics, high dk/t, low modulus, and high moisture content. Together these features mean a lens with great comfort and performance that we now off er con-fi dently to all of our monthly as well as bi-monthly replacement lens patients.

Along with a shift in strategy in the contact lens modalities I recommend has also come a change in the focus of the

questions I typically ask my patients. Be-fore, much of the conversation focused on compliance. Now, in talking to patients, I ask more specifi c questions about their contact lens wearing experience. How comfortable do your contacts feel at the end of the day? How do your contacts feel when you’re at your computer? If there’s anything about your contact lenses you’d like to change, what would it be? Many patients have been wearing the

same lens for many years so this is a good way to at least get them thinking about something new. Patients respond well to this kind of questioning – they appreciate that the doctor is taking an interest in the quality of their contact lens wear.

One patient who comes to mind is a 38-year-old returning patient, who had been wearing the same soft contact lens for almost 8 years; about a year and a half ago we had fi t her into a new monthly replacement lens that she didn’t like and had gone back to her previous bi-monthly lens. At this point she was really skeptical about trying anything new but I persuad-ed her to try the Bausch + Lomb ULTRA® lens. I expected that she would want to

wear the trial lenses for a week or two but instead she put the lenses on, walked around the store looking at sunglasses, and came back aft er 10 minutes and said “Th ese lenses are amazing!” and ordered a year’s supply. On subsequent follow-up two weeks later, the patient was extremely happy with the lenses, reporting better end-of-day comfort and less dryness.

Our offi ce prides itself in having the latest in technology – EMR, automated phorop-ters, retinal cameras – which show pa-tients that we’re innovative and up to date in terms of new technology. It’s some-thing of a let-down aft er all that to leave with the same contact lens prescription the patient has been wearing for years. Being able to off er patients an innovative product like the Bausch + Lomb ULTRA® lens that sets a high standard for comfort and performance is a much more positive experience, one that’s in line with the im-age we’re trying to present in the offi ce as a team. It’s helping to advertise that we’re about change and improvement.

Bausch + Lomb ULTRA is a trademark of Bausch & Lomb Incorporated or its affi liates. All other brand/product names are trademarks of their respective owners. US/ZUS/15/0160 S P O N S O R E D BY B A U S C H + LO M BDDDDDDDDD BBBBBBBBYYYYYYYYBYYYBYYBE DE DR E DR E D

CCCCCCOOOMFO

RTR• PERFOR

MANCE

INNO

VOOAVVTAAION

RCCL0915_BL Ultra.indd 1RCCL0915_BL Ultra.indd 1 8/20/15 1:44 PM8/20/15 1:44 PM

Over the past few decades, the preva-lence of myopia has increased exponen-tially.1,2 In many

populations—especially Asian cohorts—the morbidity associated with myopic progression can be devastating. Signifi cant elongation of the eye often results in poor uncorrected acuity. Nearly as im-portant, myopia is associated with increased risks for glaucoma, cata-racts, peripheral retinal pathology (i.e., holes, tears and detachments) and myopic macular disease.

Ongoing research is evaluating several modalities to slow the rate of myopia. These include pharma-ceutical intervention with anti-muscarinics (low-dose atropine and pirenzepine gel), orthokeratology (ortho-K) and multifocal spectacles and contact lenses. Clinical trials of ortho-K have demonstrated that progression is slowed by about 40%.1-3 Soft multifocal contact lens designs have demonstrated similar results: by reducing near eso fi xation disparity, bifocal contact lenses may improve near vision comfort and reduce accom-modation lag.1 A certain degree of protection seems to be afforded by peripheral myopic defocus lens designs.

PROFESSOR BRIEN

HOLDEN: IN MEMORIAM

Initially, I was planning to high-light Brien Holden’s fabulous work on myopia this month; I never expected to provide a memoriam honoring his memory. At this year’s British Contact Lens Association

(BCLA) meeting, Professor Holden presented a marvelous review of (1) what should concern us with myopic progression, (2) what we have learned to date and (3) how we might slow its progression.

Key points raised in his BCLA presentation include: (1) outdoor activities are essential to delay the onset and perhaps even reduce the rate of progression, (2) most soft lens designs actually promote myopia because of their negative spherical aberration in peripheral optics, (3) the recognition that ortho-K actually works and (4) the fact that peripheral plus (multifo-cal) lenses also work. Professor Holden envisioned a day when a stepped anti-myopia and extended depth-of-focus lens would be cus-tom designed for each patient with more than 0.50D of myopia.

So, is the time to act now, as Professor Holden believed? If your comfort level is adequate using lenses for a non-FDA approved indication, perhaps it is good to discuss contact lens options with parents whose children are show-ing myopic progression. Also, low-dose atropine (0.02%) may be a viable alternative for any patient unable or unwilling to wear either ortho-K or multifo-cal lenses. However, research has shown slower myopia progression, but not slowing of eye growth, so the mechanism of myopia control remains a mystery.

Ortho-K and multifocal contact lenses appear to have signifi cant benefi ts when fi tted early in myopic patients. Thus, we call upon manu-facturers to seek approval for novel

designs, as in a stepped anti-my-opia and extended depth of focus lens approach. In the meantime, I urge you to consider the exciting treatment modalities available to us today after careful and adequate education of parents and individu-als who may benefi t most when us-ing these lenses. Professor Holden’s positive and lasting impact will most defi nitely live on. RCCL

1. Anderson RL, Aller T, Walline JJ. COntrolling myopia, changing lives. Review of Cornea and Contact Lenses. 2014(9):24-29.2. Kading D, Mayberry A. Slowing myopia progression in children. Review of Optometry. 2012(11):28-34.3. Cho P, Cheung SW. Retardation of Myopia in Orthokeratology (ROMIO) study: a two-year randomized clinical trial. Invest Ophthalmol Vis. Sci. 2012. 53(11):7077-85.

The Myopia MenaceThe recent passing of Professor Brien Holden highlights the continuing need for myopia research and clinical intervention, especially with contact lenses.


My Perspective By Joseph P. Shovlin, OD

The Giant Among Giants

The eye world lost an amazing individual in July. His resume reads like a novel: 275 refereed scientifi c articles, more than 450 abstracts and more than 125 keynote addresses. Over a career that spanned more than four decades, Professor Holden received 30 international awards from diverse organizations around the world for his endless contributions to research, clinical science, public health and phi-lanthropy. He served as a mentor to so many of us and we’ll cer-tainly have a story or two to tell about how he enjoyed life. What many of our readers may not know is that Brien Holden’s PhD thesis was on the development and control of myopia, a passion he pursued tenaciously right up until his death. Professor Holden holds 10 patents with an additional nine pending, many of them related to slowing myopic progression.

006_RCCL0915_MP.indd 6006_RCCL0915_MP.indd 6 8/25/15 10:26 AM8/25/15 10:26 AM

©2014 CooperVision, Inc.

Download your Biofinity multifocal 3-step fitting guide at

coopervision.com/fitting-guide

Biofinity & Biofinity XR Biofinity toric Biofinity multifocal

Distance vision Spherical central zone

Intermediate vision Progressive zone

Near vision Spherical zone

Lens edge

Near vision Spherical central zone

Intermediate vision Progressive zone

Distance vision Spherical zone

Lens edge

Dominant eye lens Non-Dominant eye lens

Balanced Progressive™ Technology enhances vision near, far and intermediate.

It also allows for an individualized fitting for each wearer and each eye.

An

easy fit

gy enhances vision near far and intermediate

Biofinity®

multifocal

CooperVision Biofinity® multifocal lenses combine a high-performing 3rd generation material with a streamlined fitting process. Now even your most challenging presbyopic patients can enjoy the freedom of all-distance clarity and lasting comfort.

for you and your presbyopic patients.

BIOFINITY MULTIFOCAL LENSES

RO0215_Coopervision Biofinity.indd 1RO0215_Coopervision Biofinity.indd 1 1/20/15 3:42 PM1/20/15 3:42 PM

Apatient presents to your offi ce requiring a topical antibiotic for a corneal ulcer. Another patient

comes in with bilateral uveitis and needs a topical steroid. A third pa-tient complains of debilitating ocu-lar allergies. What do these patients all have in common? They are all in their fi rst trimester of pregnancy. So, keeping this in mind, what criteria do you use to guide your selection of medications?

Many practitioners have relied heavily if not exclusively on the longstanding FDA pregnancy labeling system for prescription medications to make this call. First instituted in 1979 in response to the thalidomide disaster of the early 1960s, in which thousands of babies were born with severely deformed extremities after the drug was marketed as a preventative for morning sickness, the system is comprised of fi ve categories: drugs are labeled A, B, C, D or X based on a series of predetermined FDA risk factors, with A being consid-ered the safest category. Each cat-egory was defi ned by the absence or presence of data in animals and/or humans and the study results.1

Additionally, categories D and X included information about the drug’s benefi ts for the mother, along with potential fetal risks. The FDA also determined safety data could be omitted for drugs that are not systemically absorbed as well as for drugs without suffi cient studies to demonstrate risk.2

In the years since the labeling system’s institution, however, many

shortcomings have been identifi ed; this month’s column will provide a brief overview of the impetus for change and what the change involves.

MAKING THE CHANGE

There are approximately 6.5 mil-lion pregnancies annually in the United States, with an estimated yearly pregnancy rate among wom-en ages 15 to 44 at 11%.3 In a ret-rospective study on the prevalence of prescription drug use among pregnant women, researchers found that approximately 64% of women are prescribed a drug during preg-nancy; of those receiving a prescrip-tion medication, 50% of the drugs came from category B, 37.8% from category C, 4.8% from category D and 4.6% from category X.2 Other data has suggested that as many as 80% of women receive prescription medications during pregnancy, with an average of 3.1 prescriptions per person.2 Approximately 66% of all prescription medications were labeled as category C.2

The FDA realized as early as 1997 there were problems with the 1979 labeling, but it has taken almost two decades for change to occur. Known problems include oversimplifi cation of drug use during pregnancy, the incorrect as-sumption that all drugs in a partic-ular category share the same risks, and that supporting test data is not clearly distinguished as to whether it is from animals or humans.1,2,5

To overcome these concerns, the FDA proposed the Pregnancy and Lactation Labeling Rule (PLLR) in 2008 and, after minor changes, the

fi nal PLLR was adopted effective June 30, 2015. The most striking difference between this and the old labeling system was the elimination of the pregnancy letter categories. In addition, the content and format for the labeling of prescription drugs and biological products has been reorganized with changes in titles and headings:

• Section 8 on every package insert now addresses prescription drug use in specifi c populations.

• Section 8.1 will now be called “Pregnancy” and will now include a section on labor and delivery. Other subcategories will include “Pregnancy Exposure Registry,” with directions to include contact information for enrollment if appli-cable; “Risk Summary” and “Clini-cal Considerations and Data.” The latter two sections will be required to clearly delineate if the fi ndings were from human, animal or phar-macology studies.

• Section 8.2 will now be called “Lactation, including Nursing Mothers,” which was formerly Section 8.3. This section will also contain subsections on risk and clinical considerations and data, with similar requirements to Sec-tion 8.1.

•The revised Section 8.3 is now labeled “Females and Males of Re-productive Potential.” This section will address whether pregnancy testing and/or contraception are recommended in conjunction with the drug therapy. Also addressed in this section will be any human or animal data that suggests drug-related infertility.6-8

Prescription drugs submitted to

Pharma Science & PracticeBy Elyse L. Chaglasian, OD, and Tammy Than, MS, OD

Pregnant Pause


Updates to the FDA’s pregnancy drug categorization system mean changes for your practice. What should you expect?

008_RCCL0915_PSP.indd 8008_RCCL0915_PSP.indd 8 8/25/15 10:26 AM8/25/15 10:26 AM

the FDA for approval after June 30, 2015 will immediately use this new formatting. Labeling for over-the-counter medicines, however, will not be affected by the PLLR and thus will not change. Drug ap-plications approved after June 30, 2001 will have three years to make labeling changes. Drugs approved prior to June 30, 2001 will not be required to reformat the labeling to be consistent with the new content, but will be required to remove the pregnancy risk category (i.e., A, B, C, D or X) within three years.2,7

Overall, the PLLR is expected to provide the practitioner with a better understanding of the risks associated with prescription medi-cations during pregnancy and lacta-tion. It will equip the clinician with better information including a sum-mary of the risks of using a drug, data supporting that summary and relevant information which will help when selecting medications and allow for better communica-tion to the patient about the risks/benefi ts to the patient and the fetus. Additionally, more comprehensive information will be available as well for patients of reproductive

potential who may be contemplat-ing pregnancy. Though simplicity has been eliminated, our pregnant patients who need prescription drugs will still benefi t from these signifi cant changes. RCCL

1. Feibus, KB. FDA’s proposed rule for pregnancy and lactation labeling: improving maternal child health through well-informed medicine use. J Med Toxicol. 2008;4(4):284-288.2. Ramoz LL, Patel-Shori NM. Recent changes in pregnancy and lactation labeling: retirement of risk categories. Pharmacotherapy. 2014;34(4):389-395.3. Ventura SJ, Curtin SC, Abma, JC, Henshaw SK. Estimated pregnancy rates and rates of pregnancy outcomes for the united states, 1990-2008. Natl Vital Stat Rep 2012;60:1-12. 4. Andrade SE, Gurwitz JH, Davis RL, Chan KA, et al. Prescription drug use in pregnancy. Am J Obstet Gynecol. 2004;191(2):398-407.5. Sannerstedt R, Lundborg P, Danielsson BR, Kihlstrom I, et al. Drugs during pregnancy: an issue of risk classification and information to prescribers. Drug Saf. 1996;14(2):69-77.6. U.S. Food and Drug Administration. Pregnancy and Lactation Labeling Final Rule. Available at: www.fda.gov/Drugs/DevelopmentApprov-alProcess/DevelopmentResources/Labeling/ucm093307.htm. Accessed June 15, 2015.7. U.S. Food and Drug Administration. Questions and Answers on the Pregnancy and Lactation Labeling Rule. Available at: www.fda.gov/Drugs/DevelopmentApprovalProcess/DevelopmentRe-sources/Labeling/ucm093311.htm Accessed June 15, 2015.8. U.S. Food and Drug Administration. Content and Format of Labeling for Human Prescription Drugs and Biological Products: requirements for preg-nancy and lactation labeling. Available at: https://s3.amazonaws.com/public-inspection.federalregis-ter.gov/2014-28241.pdf. Accessed June 15, 2015.

11 Campus Blvd., Suite 100

Newtown Square, PA 19073

Telephone (610) 492-1000

Fax (610) 492-1049

Editorial inquiries: (610) 492-1003

Advertising inquiries: (610) 492-1011

Email: [email protected]

EDITORIAL STAFF

EDITOR-IN-CHIEFJack Persico [email protected]

SENIOR ASSOCIATE EDITORAliza Becker [email protected]

CLINICAL EDITORJoseph P. Shovlin, OD, [email protected]

EXECUTIVE EDITORArthur B. Epstein, OD, [email protected]

ASSOCIATE CLINICAL EDITORChristine W. Sindt, OD, [email protected]

CONSULTING EDITORMilton M. Hom, OD, [email protected]

GRAPHIC DESIGNERMatt Egger [email protected]

AD PRODUCTION MANAGERScott Tobin [email protected]

BUSINESS STAFF

PUBLISHERJames Henne [email protected]

REGIONAL SALES MANAGER Michele Barrett [email protected]

REGIONAL SALES MANAGER Michael Hoster [email protected]

VICE PRESIDENT OPERATIONSCasey Foster [email protected]

EDITORIAL BOARD

Mark B. Abelson, MD

James V. Aquavella, MD

Edward S. Bennett, OD

Aaron Bronner, OD

Brian Chou, OD

S. Barry Eiden, OD

Gary Gerber, OD

Susan Gromacki, OD

Brien Holden, PhD

Bruce Koffler, MD

Pete Kollbaum, OD, PhD

Jeffrey Charles Krohn, OD

Kenneth A. Lebow, OD

Kelly Nichols, OD

Robert Ryan, OD

Jack Schaeffer, OD

Kirk Smick, OD

Barry Weissman, OD

REVIEW BOARD

Kenneth Daniels, OD

Desmond Fonn, Dip Optom M Optom

Robert M. Grohe, OD

Patricia Keech, OD

Jerry Legerton , OD

Charles B. Slonim, MD

Mary Jo Stiegemeier, OD

Loretta B. Szczotka, OD

Michael A. Ward, FCLSA

Barry M. Weiner, OD

RCCLRCCLREVIEW OF CORNEA & CONTACT LENSES

CURRENT LABELING NEW LABELING

FDA Prescription Drug Labeling Changes

Sections 8.1 to 8.3: “Use in Specifi c Populations”

(eff ective June 30, 2015)

8.1 Pregnancy 8.1 Pregnancy

8.2 Labor and Delivery 8.2 Lactation

8.3 Nursing Mothers8.3

Includes Labor and Delivery

Includes Nursing Mothers

Females and Males ofReproductive Potential

NEW

Source: FDA

008_RCCL0915_PSP.indd 9008_RCCL0915_PSP.indd 9 8/25/15 10:26 AM8/25/15 10:26 AM

With the year rolling along, have you taken the chance to evaluate

the progress of your contact lenses business? Is your growth where you would like it to be, or are you experiencing the all-too-familiar feeling of just treading water? We all are aware of the often-cited statistic that about 16% of contact lens patients drop out of lens wear each year, essentially eliminating the gains we might have experi-enced from new patients entering the modality. Many practices end the year with the same number of contact lens patients they started with. What will it take to break the cycle? A broader view of who’s a candidate for contact lens wear.

Many practices rely on everyday wearers as their primary source of contact lens revenue—they’re easy to fi t and easy to please—but forgo considering specialty and custom contact lens wearers. Patients with unique visual demands and/or more challenging ocular anatomy to con-tend with have often been told they cannot wear contact lenses, due to an irregular cornea or high amount of astigmatism. Others who wore contact lenses previously may have given up due to discomfort or fi t issues. While these patient types will take a bit more effort and exper-tise than a garden-variety -3.00D myope with healthy eyes, when handled correctly they can be your biggest catalysts for growth.

In this newly retooled column, now called Practice Progress, we’ll focus on strategies for growth

as well as retention. Success in a contact lens practice requires more than just “derailing dropouts,” the topic we addressed for the last eight years. It also takes a willingness to embrace new ideas, lens technolo-gies and challenges. Custom-fi tting contact lenses for challenging cases is the perfect place to start.

SPREAD THE WORD

The fi rst step to getting these pa-tients on your side is making them the offer of custom lenses. It sounds simple, but many patients have preconceived notions that they can-not wear lenses. Once the patient expresses interest in trying a custom lens, record their history, including their occupation, hobbies and daily visual requirements, and discuss suitable lens options with them. Technology can aid with determin-ing the correct lens option for each patient. Topography is a must for corneal mapping, while anterior segment OCT can aid in fi tting vaulted lenses. Newer OCT applica-tions can image the tear fi lm to get a better sense of tear dynamics, so even borderline dry eye patients can wear contact lenses.

Custom contact lens offerings comprise a large number of lens types, including those for high and irregular astigmatism, keratoconus, post-traumatic and post-refractive corneas, myopia control, poor visu-al acuity and ocular surface disease. Because of the uncommon nature of some of these lenses, fi tting these patients often takes more time and energy; thus, many practitioners don’t even make the offer. Below, we review a few patient populations

who have custom lens options to consider.

HIGH ASTIGMATIC PATIENTS

These patients offer a good oppor-tunity to add a signifi cant number of underserved contact lens wearers to your offi ce. While there are many toric options available in the soft contact lens market, on-eye lens sta-bility can sometimes be a challenge for those with moderate to high levels of astigmatism, especially of the irregular variety. Uncorrected astigmatism and the subsequent dis-torted vision results in frustration, headaches and eye fatigue.

For these patients, gas perme-able (GP) lenses provide more stable vision than traditional soft lenses and mask corneal irregulari-ties. Though GPs typically require longer adaptation times, spherical GPs are often a great starting lens. However, patients with signifi cantly higher astigmatism (i.e., more than 3.00D cyl), may need a back toric or bitoric GP lens to further ensure lens stabilization.

ASTIGMATIC PRESBYOPES

Another great opportunity to improve the patient’s contact lens experience is the high astigmat with presbyopia. GPs can often be fi t empirically for these patients and typically provide the greatest range of clear vision at all focal lengths near to distance. GP multifocals are often the best way to ensure good visual function. These lenses are typically customized to the patients’ specifi c cornea shape and visual needs. Note that some lens movement is necessary, but signifi -

Meet the CandidatesMore patients can wear contact lenses than you might think. Custom designs can turn missed opportunities into success stories.

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

Practice Progress


010_RCCL0915_PP.indd 10010_RCCL0915_PP.indd 10 8/25/15 10:27 AM8/25/15 10:27 AM

cant movement will impede visual function.

Soft toric multifocals are another good option for these patients. To properly fi t theses lenses, fi t the toric aspect fi rst and adjust for rota-tion and instability before fi tting the multifocal aspect. As with any lens, be sure to discuss appropriate visual expectations and the importance of follow-up care. For this technology, on-eye stabilization is key.

Hybrid lenses are a third possibil-ity for patients who desire the clear vision of GP lenses with the com-fort of soft lenses, as the soft skirt surrounding the rigid center helps reduce lens awareness. The second-generation Duette multifocal lenses (SynergEyes) are currently the only hybrid lens with a silicone hydrogel skirt (Dk=84).

CORNEAL IRREGULARITIES

There are a number of scleral lens designs available for corneal irregularities like keratoconus, post-trauma and post-surgery, includ-

ing corneal-scleral, semi-scleral, mini-scleral and conventional scleral fi ts. These rigid lenses are becoming increasingly popular due to their ability to mask irregularities while being better tolerated than traditional corneal GPs. As scleral lenses are fi t to vault the cornea, much of the lens rests on the sclera, as opposed to the cornea. Typi-cally, their diameter is greater than 10mm; fi tting sets are a must for this technology.

Additionally, there are a few soft designs for the irregular cornea. These lenses typically use thicker center optic zones to mask ir-regularities. Some limits exist with these designs, but they may be a good option for mild to moderately distorted corneas.

CASE IN POINT

A new 44-year-old male patient presented with complaints of decreased vision with his glasses at distance and near. He reported his vision was worse in his right eye and that he had been told at his previous eye exam that he may have keratoconus; however, he had never been fi t with contact lenses. His BCVA was 20/30 OD with an Rx of +2.50-4.00x049 and 20/20 OS with an Rx of +0.75-2.00x132. He was trial fi t into the NovaKone (Alden) soft keratoconic contact lens, and later fi t with the Nova-Kone Toric for his right eye and the NovaKone Sphere for his left eye (Figure 1). His vision with contact lenses was equal to his best cor-rected spectacle prescription, and he expressed satisfaction with his vision and comfort.

DEVELOPING YOUR MARKET

Though you have an existing patient base to draw from, it is important to develop marketing tactics to expand this group. Some possibilities include talking to other doctors in the area—including oph-thalmologists, primary care practi-tioners and even school nurses—to spread the word of your ability to fi t custom lenses. These profession-als would welcome the opportunity to help their patients and would have no problem admitting their shortcomings in this particular area of care; knowing a specialist to refer their patients to gives them the abil-ity to help without the obligation of developing the expertise in-house.

In addition, consider external and internal advertising efforts such as newsletters, emails, websites and social media outlets. Don’t forget to capture the reaction of your patients as they experience a successful fi t and use it to promote your practice. For instance, a happy patient who’s just been fi t with a custom lens might want to post a selfi e right from your exam chair, providing everyone in their social network with an endorsement for your practice. Boom—instant, real-time marketing. And it’s free.

The above options offer a unique platform and design, which allows the contact lens practitioner to provide unique products to your patients. Some patients will be intolerant of any lens design, but in those instances where a patient would benefi t from the optics that a GP delivers, but cannot wear the lenses because of discomfort issues, consider a soft or hybrid lens. RCCL


Fig. 1. The center optic zone is apparent

in this photo. The NovaKone (Alden) has

variable lens center thickness (IT Factor)

to neutralize irregular astigmatism;

however, a higher IT Factor is necessary

for more advanced levels of keratoconus.

010_RCCL0915_PP.indd 11010_RCCL0915_PP.indd 11 8/25/15 10:27 AM8/25/15 10:27 AM


Although contact lenses are classifi ed as medical devices and subject to the same stringent FDA

approval process as cardiac stents, orthopedic implants and any other manufactured health aid, they are increasingly seen by many as a commodity. Before the era of mass production, conventional contact lenses were lathe-cut and made to order, with varying diameters and base curves. Then, in the late 1980s, the fi rst disposable soft contact lenses were produced using a cast-mold production process, forever changing the industry. Since then, stock lens offerings have increased exponentially. Patients enter a competitive con-sumer environment upon leaving the exam room, one that is complicated by a range of discount vision plans and online retailers who emphasize cost savings and little else.

In light of this downgrade of contact lenses in the public sphere—from medical device to commodity product—it is easy to

see why many patients lose sight of the value of our expertise in choos-ing an appropriate lens. This trend is especially concerning for patients with higher demands on their vi-sion who have struggled to fi nd an appropriate stock lens. Educating patients regarding your ability to personalize their fi t with custom-designed lenses can help you better meet their needs and stand apart from competition.

POTENTIAL CANDIDATES

By defi nition, a custom contact lens is any soft, gas permeable (GP) or hybrid lens design that is made to order, with multiple design pa-rameters that can be manipulated. Although irregular cornea applica-tions may come to mind fi rst as the best use of custom lenses, they can address many patients' refractive needs that are not being met with standard “off-the-rack” disposable contact lenses.

• Astigmatic Patients. How often do patients mention they have been told they cannot wear contact lenses because of their astigmatism? An estimated 90%

of astigmatic patients can be fi t in the parameters available with stock soft toric lenses, which typi-cally includes a range of +6.00D to -9.00D in spherical power and up to -2.25D cylinder power.1 For patients outside of this range, custom soft toric lenses are an option. Depending on the labora-tory, from 8.00D up to 12.00D of astigmatism can be incorporated with one-degree axis steps. With larger amounts of astigmatism, cylindrical axis refi nement is criti-cal. Custom lenses can be lathe-cut to nearly any base curve, diameter and prism to improve rotational stability.

When patients express a desire for better vision, consider dis-cussing GP lenses, as they offer a

Dr. Ensley is in private practice in Louisville, Ky., where he specializes in fi tting specialty contact lenses. He completed a residency

in cornea and contact lenses at the University of Missouri-

Saint Louis and is a Fellow of the American Academy of Optometry.

ABOUT THE AUTHOR

Making the Case For

Custom LensesBy Robert Ensley, OD

014_RCCL0915_F1.indd 12014_RCCL0915_F1.indd 12 8/25/15 12:49 PM8/25/15 12:49 PM

superior quality of vision com-pared with soft toric lenses.2,3 As a general rule of thumb, spherical GPs can be used when refrac-tive astigmatism equals corneal astigmatism of less than 2.5D. If there is any residual astigmatism, it can be applied to the front surface. However, in cases of higher corneal astigmatism, back-surface or bi-toric GPs are typically used.

If initial comfort with corneal GP lenses is a concern, consider prescribing hybrid or scleral lenses instead. Many GP laboratories are now marketing smaller diameter scleral lenses to fi t the “normal” cornea. These specialty lenses pro-vide stable, higher quality vision with comfort rivaling soft toric lenses.4

• Corneal Shape. Most stock soft lenses take a “one-size-fi ts-all” approach, with only one diameter and one base curve to choose from. If two base curves are available, however, the choice is most often made using keratometry readings. Sagittal depth of the cornea, which is infl uenced by corneal diameter, may also play a signifi cant role in the lens-cornea fi tting relation-ship. Corneal diameter is typically measured by horizontal visible iris diameter (HVID), with aver-age corneal diameter measuring 11.8mm.5,6 Patients with an HVID outside the typical range can expect a lens to decenter, reduc-ing both the patient’s quality of vision and comfort. To solve this, base curves and diameter can be manipulated with custom lenses to change the overall sagittal depth of a lens and thus better match corneal shape.

• Presbyopes. The strain placed on near vision in our technology-driven world, coupled with the in-fl ux of presbyopic patients, has put multifocal lenses more in demand than ever. The ability to change multiple design parameters once again increases the odds for suc-cess. Knowing the patient’s desired working distance can help in the decision-making process. If higher add powers are required, many GP multifocals have adds greater than 3.0D. Certain custom laboratories such as SpecialEyes can manufac-

ture lenses with an add power up to 4.0D at 0.10D increments.

Most gas permeable and custom soft multifocals rely on aspheric, simultaneous vision designs. Depending on the specifi c design of the lens, adjusting zone sizes inf relation to pupil size can improve the optics. For example, if a center-distance, aspheric GP multifocal has a standard distance zone of 3.95mm, patients with a smaller pupil diameter may have diffi culty achieving great near vision, while those with larger pupil diameters


Finding a lens for every patient can boost your practice and your profi ts.

SPECIAL ISSUE:

CUSTOM LENSES

Case #1: The Presbyope with Large HVID

A 44-year-old pilot present-ed complain-ing of de-creased near vision with his habitual progressive add spec-

tacles. He was interested in trying contact lenses for the fi rst time. Given his occupation, there is a high demand on his vision at various working distances. Spectacle Rx was 0.00 0.75x090 OD and 0.00 0.50x095 OS, with an add of +1.50. Keratometry readings were 42.25/42.75 at 180 OU. A pair of standard center-near monthly replacement multifocals was placed on his eyes, but were decentering superiorly with excessive movement.

A pair of custom center-near aspheric soft multifocals was ordered using spherical equivalent power for the distance correction. The base curve and diameter was adjusted to 8.4mm and 15.2mm OU to improve the fi tting relationship. Given a pupil diameter of 4.0mm in ambient light, the center-near zone was set at 2.0mm extending to a 3.5mm intermediate zone. With these lenses, he was able to comfortably achieve 20/20 distance vision in each eye and read his phone and an iPad that he uses in the cockpit.

SPSSSPECIAAL ISSSUUUEE:

CCCCUCUUUUCUUUSSSTOMM LLENNNSSEESSCCCCUCUUUUCUUUSSSTOMM LLENNNSSEESS

SPECIAL ISSUE:



may have shadowing and glare at distance, especially in scotopic con-ditions. Center-near custom soft multifocals allow both near and intermediate peripheral zones to be adjusted dependent on pupil size.

Patients looking for crisp, uninterrupted vision at both dis-tance and near may do better in a translating GP multifocal because it avoids the inherent limitations of simultaneous vision designs. However, pay careful attention to lower lid anatomy before begin-ning the fi tting process to make sure the lens can rest appropriately on the lid and translate upward as needed. The lower lid should be at or within 1mm from the limbus, without signifi cant laxity, to allow for appropriate transla-

tion. If centration or comfort is a concern, you may consider fi t-ting hybrid or scleral multifocals. Scleral multifocals may serve a dual purpose—that is, correcting presbyopic refractive error and treating underlying dry eye.

• Myopia Control. Many prac-titioners are now using contact lenses for myopia control—in fact, an audience poll at the 2014 American Optometric Association (AOA) annual meeting found that 32% of participants prescribed soft multifocal lenses and 29% pre-scribed orthokeratology lenses for this purpose.7

A recent myopia control study with soft multifocal contact lenses used a center-distance design with a +2.00D to reduce peripheral

blur.8 Currently, the only mass-produced lenses that can provide such a design include the Biofi nity Multifocal (Cooper Vision), Pro-clear Multifocal (Cooper Vision) and Acuvue Oasys for Presbyopia (Johnson & Johnson Vision Care). This presents an opportunity for a custom multifocal. The ability to adjust zone sizes, incorporate astig-matism power and increase the add power, if tolerated, can increase the likelihood of successful wear. Additionally, a custom lens may help reinforce both the off-label nature and extra level of care you are providing to the patient.

Orthokeratology lenses, which are custom GPs with a reverse geometry design, for corneal cor-rection if daytime lens wear is either uncomfortable or not an option due to environmental or occupational reasons. These lenses are more commonly prescribed for children, but can be worn by adults as well and are fi t both diag-nostically and empirically.

PERSONALIZED FITTING

Identifying candidates for custom contact lenses begins with taking a case history. Many non-contact lens wearers believe their prescrip-tions exclude them from contact lens wear. Similarly, for both current and former contact lens pa-tients, inquiring about their wear-ing experiences can help you better tailor a custom lens option for them. Once the need for a custom lens is established, patients can be fi t diagnostically or empirically.

Diagnostic fi tting evaluates the lens-to-cornea fi tting relationship of various lenses; however, this approach may increase chair time during the initial evaluation. Cer-tain lenses, including translating GPs and scleral lenses, are better fi t diagnostically.

MAKING THE CASE FOR CUSTOM LENSES


Case #2: The High Astigmat

A 24-year-old graduate student presented wearing soft toric lenses, but only part-time because he reported that vi-

sion is better in spectacles. In addition to better clarity when using spectacles, he reported fl uctuating vision when blinking in his con-tact lenses.

His Rx was -10.50 3.00x005 OD and -11.50 2.00x160 OS with kera-tometry readings of 43.25/45.25 at 089 OD and 43.50/44.75 at 074 OS. Because of the poten-

tial for residual astigmatism in a GP lens, a custom soft toric lens was initially chosen.

Custom soft toric lenses were empirically ordered using the Defi nitive (efrofi lcon A, Contamac) material. Given his signifi cant level of myopia and thicker lens periphery, a sili-cone hydrogel material was preferable. After vertexing, the following lenses were ordered: -9.25 2.75x005 with an 8.2 base curve and 14.8 diameter OD and -10.25 1.75x160 with an 8.3mm base curve and 14.8mm diameter. He was able to achieve stable, 20/20 vision in each eye and was thrilled with his vision. He is now wearing his contact lenses daily.


Because most practices do not carry a large GP inventory or mul-tiple diagnostic sets, empirically ordering GP lenses is often the preferred approach for many prac-titioners. In addition to potentially reducing chair time, empirically designed GPs have been proven to be accurate.4 When ordering em-pirically, manifest refraction and keratometry readings are required for GP, hybrid and custom soft lenses. Choosing the initial lens diameter for a GP lens can be done after assessing the upper eyelid position. Generally, if the eyelid is positioned at or near the upper limbus, a lid-attached fi t can be achieved with a diameter of 9.4mm or greater. An interpalpebral fi t may require a smaller, steeper lens with a diameter of 9.2mm or less.

Fitting toric GPs may seem intimidating, but there are multiple fi tting nomograms and resources

available to help design these lenses, such as www.gpli.info/lens-calculator/. Using spectacle refrac-tion and keratometric readings, the lens calculator will recommend either a spherical or toric GP lens, and will provide parameters. For presbyopic patients being fi t with either GP or custom soft multifo-cals, measuring pupil size in both photopic and scotopic condi-tions can help determine initial zone sizes. Keep in mind that add power may vary depending on the patients’ most desired working distance.

Corneal topography is a great tool to use when fi tting custom lenses. Multiple measurements such as keratometric readings, HVID, pupil size and corneal ec-centricity can be obtained in a mat-ter of minutes. Additionally, many topography software programs can simulate sodium fl uorescein pat-

terns of a calculated contact lens. Custom lenses also differ in care

requirements compared to “off-the-rack” lenses. Replacement schedules vary depending on the type of lens and the discretion of the prescribing doctor, but typi-cally range from quarterly to annu-ally. Proper care and disinfection is essential to maintaining the life of each lens. In addition to standard disinfection systems, additional solvent cleaners or enzymatic cleaners can be used periodically.

Custom contact lenses can be a tough sell to patients used to the simplicity of online ordering and instant gratifi cation. But just as a tailored suit looks and feels better than a department store’s in-stock options, lenses created expressly for each individual’s visual needs and ocular anatomy will perform better. With a little extra attention during the fi t and careful patient education, you can create a truly individualized approach that gives patients superior outcomes and re-inforces your expertise. The result? Happier, more loyal patients and a healthier bottom line. RCCL

1. Young G, Sulley A, Hunt C. Prevalence of astig-matism in relation to soft contact lens fi tting. Eye & Contact Lens. 2011;37(1):20-5.2. 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;80:375-83.3. Fonn D, Gauthier CA, Pritchard N. Patient preferences and comparative ocular responses to rigid and soft contact lenses. Optom Vis Sci.1995;72(12):857-63.4. Michaud L, Woo S, Dinardo A, et al. Clinical evaluation of a large diameter rigid gas-per-meable lens for the correction of refractive astigmatism. Poster presented at the American Academy of Optometry Annual Meeting. 2012; Phoenix, AZ.5. Douthwaite WA. Initial selection of soft contact lenses based on corneal characteristics. CLAO J. 2002. Oct;28:202-5.6. Caroline P, André M. The eff ect of corneal diameter on soft lens fi tting, part 1. Contact Lens Spectrum. 2002;17(4)56.7. Quinn TG, Walline JJ, Sonsino J, et al. Controver-sies in contact lens care. Contact Lens Spectrum. 2015;30(1):34-40.8. Walline JJ, Greiner KL, McVey ME, Jones-Jordan LA. Mulitfocal contact lens myopia control. Optom Vis Sci. 2013;90:07-1214.


Case #3: The Astigmatic Athlete

A 23-year-old professional baseball player presented to the offi ce for contact lens evaluation. He was wearing stan-dard soft toric lenses, but complained of fl uctuating vision. As a competitive athlete, it was critical that his vision be as crisp and stable as pos-sible. His Rx was +1.00 1.75x097 OD +1.25 2.00x071 OS, with keratom-etry readings of 41.75/43.00 at 003 OD and 41.75/43.50 at 167 OS.

We selected hybrid lenses to provide GP op-tics without the concern for lens rotation or dislodgement. The lenses provided 20/15 vision in each eye. The patient reported they were both comfortable.



Gas permeable (GP) lenses tend to be our “go-to” option for specialty contact lens fi ts. However,

while their use is intuitive for cases of keratoconus and other irregular astigmatic corneas, many other patients would benefi t from the crisp vision GP lenses provide or the additional health benefi ts associated with their use. The wide availability of soft lens modalities and parameters, coupled with the added time and complexity of fi tting GP lenses rather than soft lenses, means that GPs comprise less than 10% of total fi ts today.

In reality, GP lens fi tting is straightforward, especially when you have the appropriate tools of the trade—diagnostic GP fi tting sets—at your fi ngertips. Forgo-ing fi tting the lens empirically and observing it yourself on the eye will allow you to make a more informed decision on what parame-ters will work best for your patient. Let’s look at both empirical and diagnostic fi tting methods.

EMPIRICAL FITTING

This approach involves fi tting a GP lens based on manufacturer guidelines, K readings and refrac-

tive measurements. As the simplest method, it saves chair time.1 Recent manufacturing improvements such as the advent of aspheric lathes and more consistent edge profi le designs and minimal center thicknesses have further increased its success rate.

The downside of empirical fi tting is that success with the fi rst lens fi tted is only about 40% when em-ploying K readings and refractive measurements.2 Use of topographic software as well as incorporation of the Sim K information and the patient’s corneal e-values or asphe-ricity can help make the lens design more accurate, however. Many corneal topographers are capable of generating a pseudo-fl uorescein pattern based on the lens design (i.e., spherical, aspheric and even toric) desired, allowing practitio-ners to order lenses without the initial placement of a lens on the patient’s eye.

Empirical lens fi tting can also be done using online resources (such as those found at GPLI.org) or smartphone apps like EyeDock (www.eyedock.com). However, empirical lens fi tting without the advantages of topography and computer-assessed pseudo-fl uores-cein patterns is likely to result in

more lens orders and exchanges until the patient is appropriately fi t. This ultimately results in more offi ce time and possibly less patient confi dence in the practitioner than would have occurred had the fi tting been done with the benefi t of a diagnostic GP lens evaluation.

DIAGNOSTIC GP

LENS FITTING

This technique provides the ad-vantage of observing one or more test lenses, which are similar to the empirical lens values described above, on the patient’s eyes prior to ordering. In this case, the lenses that provide the best lens-to-cornea relationship, as well as good cen-tration and movement, are the ones that should be chosen. Diagnostic lens fi tting provides important information as to what visual acuity can be achieved. Residual

Dr. Silbert is a professor of optometric medicine at Pennsylvania College of Optometry, Salus University. He is also the director of cornea and specialty contact

lens services at the Eye Institute of Salus University. He

has no fi nancial interests in any of the lens materials or designs discussed in this article, nor any fi nancial interests in any of the companies’ products mentioned herein.

ABOUT THE AUTHOR

An expert walks you through the fi ner points of the process to help you achieve better results.

GPs:

7.387.427.467.507.547.587.637.677.717.757.807.857.897.947.998.048.088.138.188.23

88881

81

81

81

81

81

9

81

9

81

8.18

7.994

7 9988.8.1318

8.18

10.4/0.210.4/0.210.5/0.210.5/0.210.6/0.210.6/0.210.6/0.210.7/0.210.7/0.210.8/0.210.8/0.210.9/0.210.9/0.211.0/0.211.0/0.211.0/0.211.1/0.211.1/0.211.2/0.211.2/0.2


astigmatism, if signifi cant, is often observed along with reduced acuity; this improves once additional astigmatic correction is provided via over-refrac-tion. Its presence may indicate that the lens is too thin, and fl exing on the eye. Conversely, in some cases residual astigmatism may be higher with more rigid (thicker) lenses; thus, thinner lenses would in fact be more benefi cial.3

Patients who undergo di-agnostic lens fi tting should be forewarned of the dif-ferences between GPs and soft contact lenses. Many GP lens patients experience excessive lacrimation and foreign body sensation as a result of initial lens place-ment, so use proparacaine during initial diagnostic lens fi tting to numb the eye. Additionally, while the initial test lens applied to the patient’s eyes may not enable them to see clearly immediately, performing an over-refraction can as-sure them that vision will be correctable to excel-

lent levels similar to what they may enjoy with their glasses.

Diagnostic lens fi tting is highly likely to result in fewer lens changes or reorders, as the fi tting gives the practitioner a great deal of informa-tion, increasing confi dence in the lens fi tting process. Patient satisfac-tion is also quite high, despite the added time commitment diagnostic fi tting may entail compared with soft lens fi ttings.

Empirical lens design is not advised in cases where specialized lenses are needed, such as with keratoconus or post-keratoplasty patients, and with ortho-keratology fi ttings. In these cases, specialized diagnostic fi tting sets are required to properly assess lens performance, vision and proper lens-to-cornea fi t-ting relationships. This is especially true for patients with keratoconus due to the different cone shapes and locations; patients with pellucid marginal degeneration who require much larger GP lenses to assist in lens centration; and patients who wear bifocal lenses due to variations in pupil size and GP lens designs (i.e., center distance, center near, concentric, spherical and aspheric.)

One exception is the ReClaim HD lens (Blanchard), a multifocal GP lens designed to be fi t empirically.


By Joel A. Silbert, OD, FAAO

• Diameter 9.4/8.0 (or 9.2/7.8)

• Power -3.00D

• Peripheral curves are tetracurve design,

similar to the Bennett system8

• Center thickness 0.14mm standardized

BCR SCR/W ICR/W PCR/W

7.38 8.2/0.3 9.2/0.2 10.4/0.2

7.42 8.2/0.3 9.2/0.2 10.4/0.2

7.46 8.3/0.3 9.3/0.2 10.5/0.2

7.50 8.3/0.3 9.3/0.2 10.5/0.2

7.54 8.3/0.3 9.3/0.2 10.6/0.2

7.58 8.4/0.3 9.4/0.2 10.6/0.2

7.63 8.4/0.3 9.4/0.2 10.6/0.2

7.67 8.5/0.3 9.5/0.2 10.7/0.2

7.71 8.5/0.3 9.5/0.2 10.7/0.2

7.75 8.6/0.3 9.6/0.2 10.8/0.2

7.80 8.6/0.3 9.6/0.2 10.8/0.2

7.85 8.7/0.3 9.7/0.2 10.9/0.2

7.89 8.7/0.3 9.7/0.2 10.9/0.2

7.94 8.8/0.3 9.8/0.2 11.0/0.2

7.99 8.8/0.3 9.8/0.2 11.0/0.2

8.04 8.8/0.3 9.8/0.2 11.0/0.2

8.08 8.9/0.3 9.9/0.2 11.1/0.2

8.13 8.9/0.3 9.9/0.2 11.1/0.2

8.18 9.0/0.3 10.0/0.2 11.2/0.2

8.23 9.0/0.3 10.0/0.2 11.2/0.2

Table 1. Fixed Diameter GP

Spherical Diagnostic Fitting Set

Are You Making Good Use of Diagnostic Fitting Sets?

SPECIAL ISSUE:



Blanchard does not make diagnos-tic fi tting sets available; instead, an online calculator employing K readings (or Sim Ks) and refractive data will inform the practitioner about the lens parameters that will be provided, and give him/her the ability to adjust add power and other parameters if desired. Note, if residual astigmatism is calculated to be excessive or if inadequate levels of plus reading power would be produced by the lens rear surface aspheric geometry, other options need to be explored through con-sultation.

Toric GP lenses are often calcu-lated empirically, and frequently with the assistance of the Mandell-Moore Bitoric Fitting Guide (avail-able at www.gpli.info/mandell-moore). This step-by-step empirical method does all the calculations necessary to produce a fi rst bitoric lens for the moderate to highly astigmatic contact lens patient. It

provides a good starting point, and in many cases works well in designing a lens that does not need a lot of additional parameter manipulation.4 Use of diagnostic spherical power effect (SPE) fi tting sets, in which each lens in the set is pre-designed with spherical lens optics, makes diagnostic lens fi tting extremely easy; the fl uorescein analysis that an SPE bitoric fi tting set provides enables the practitioner to rapidly select the right amount of rear surface toricity, and then determine the correct power rapidly through over-refraction.5-7

DIAGNOSTIC FITTING OF

CONVENTIONAL GP LENSES

When fi tting conventional corneas (i.e., to correct astigmatism, pro-vide sharper visual acuity or slow pediatric myopic refractive error), it is recommended to have more than one diagnostic GP lens set—for example, an average diameter GP

fi tting set and a larger diameter set for “under-the-lid” fi tting, which is typically more comfortable and more easily centered. Conventional GP fi tting sets on average measure 9.2 to 9.4mm in size, with an optic zone diameter 1.4mm smaller than the total diameter.8 Powers for these lenses are typically made in -3.00D, as this is close enough for most pa-tients’ refractive errors to be within a range such that over-refractions do not need to be adjusted further.

While there can be variations with high or low Dk GP lens materials, diagnostic sets are best manufactured in a mid-range Dk material with a low wetting angle to ease tear spreading on the lens surface. While many practitioners may have fi tting sets in both low Dk and high Dk materials, a Dk of somewhere between 30 and 60 is recommended. As there are many peripheral curve formulas avail-able, it is best to standardize these in the set’s diagnostic lenses using a formula that ensures the second-ary curve (SCR), intermediate curve (ICR or TCR) and peripheral curve (PCR) have the same fl atten-ing relationship predicated on the selected base curve.

An example of a 20-lens diag-nostic fi tting set is seen in Table 1. These can be manufactured by any CLMA contact lens laboratory, and are typically provided to the practi-tioner at very lost cost (assuming of course that the practitioner orders their lenses through the manufac-turing CLMA laboratory).

In addition to the standard fi tting set mentioned above, it is prudent to have another in high minus powers (with plus lenticulated edges) and one in high plus pow-ers (with minus carrier lenticulated edges). These supplementary sets provide more accurate information regarding how lenses center, as the

GPs: ARE YOU MAKING GOOD USE OF DIAGNOSTIC FITTING SETS?


• Diameter varies with base curve (BC)

• Back Vertex Power (BVP) varies with BC

• PCs standardized to provide relatively constant edge lift (0.09-0.11mm)

BCR Back Vertex Power Diameter/OZD SCR/W ICR/W PCR/W

8.40 (40.25) -2.00D 9.6 / 8.2 9.2 / 3 10.2 / 0.2 11.6 / 0.2

8.30 (40.62) -2.00D 9.6 / 8.2 9.1 / 3 10.1 / 0.2 11.5 / 0.2

8.20 (41.12) -2.00D 9.6 / 8.2 9.0 / 3 10.0 / 0.2 11.4 / 0.2

8.10 (41.67) -2.00D 9.4 / 8.0 8.9 / 3 9.9 / 0.2 11.3 / 0.2

8.00 (42.25) -2.00D 9.4 / 8.0 8.8 / 3 9.8 / 0.2 11.2 / 0.2

7.90 (42.25) -3.00D 9.4 / 8.0 8.7 / 3 9.7 / 0.2 11.1 / 0.2

7.80 (43.25) -3.00D 9.4 / 8.0 8.6 / 3 9.6 / 0.2 11.0 / 0.2

7.70 (43.75) -3.00D 9.4 / 8.0 8.5 / 3 9.5 / 0.2 10.9 / 0.2

7.60 (44.37) -3.00D 9.4 / 8.0 8.4 / 3 9.4 / 0.2 10.8 / 0.2

7.50 (45.00) -3.00D 9.4 / 8.0 8.3 / 3 9.3 / 0.2 10.7 / 0.2

7.40 (45.62) -4.00D 9.2 / 7.8 8.2 / 3 9.2 / 0.2 10.6 / 0.2

7.30 (46.25) -4.00D 9.2 / 7.8 8.1 / 3 9.1 / 0.2 10.5 / 0.2

7.20 (46.87) -4.00D 9.2 / 7.8 8.0 / 3 9.0 / 0.2 10.4 / 0.2

7.10 (47.50) -4.00D 9.2 / 7.8 7.9 / 3 8.9 / 0.2 10.3 / 0.2

Table 2. Variable Diameter GP Diagnostic Fitting Set


Atlantis™ Scleral

Two larger diameters in 17.0 & 17.5 creates

more sagittal depth for the highly irregular corneas.

Large Diameter

Introducing the Next Generation...

Atlantis™ Scleral with its 1 • 2 • 3 FIT STRATEGY has evolved. The Atlantis PRO Series includes all of the great

benefits of the original Atlantis lens and features larger diameter options along with two toric enhancements.

© 2015 X-Cel Specialty Contacts

Contact X-Cel Specialty Contacts to learn more.800.241.9312 | [email protected]

RCCL0915_Hydrogel.indd 1RCCL0915_Hydrogel.indd 1 8/24/15 9:40 AM8/24/15 9:40 AM

average thickness of the lenses in these various powers would differ and thus affect lens positioning. In cases where this is not economically feasible, a standard set of -3.00D power will usually suffi ce, as it refl ects the most typical patient refractive powers seen in practice.

Another option for a practitioner-designed supplementary diagnostic fi tting set is one with a variable diameter (i.e., larger lenses for fl atter corneas and smaller lenses for steeper corneas). This set could also have variable lens powers, with lower powers for fl atter lenses and higher powers for steeper base curves. Table 2 represents a 20-lens diagnostic set designed by the author and manufactured by Valley Contax for use in an optometric training program.

When cost is not a factor, such as in an institutional practice or large group practice, having a large inventory of GP lenses made in a variety of base curves for the most commonly prescribed myopic powers (i.e., from -1.25D through -5.00D in 0.25D steps). For ex-ample, having a 200-lens inventory set would make it easy to dispense lenses directly out of inventory even on the fi rst visit, as typically is done with hydrogel replacement lenses. This would help reduce dispensing delay and make parameter changes easy, as well as enable instant lens replacement for patients who lose or damage their lenses. Maintain-ing the inventory is critical to this method’s success; while initially expensive, it does provide good economy of time and in patient satisfaction.9

While there is a place for empiri-cal fi tting of GP lenses, practitio-ners should remember the use of diagnostic lens fi tting sets, whether for conventional lens design, or for more complex lenses, can only lead

to more accurate and satisfying use of these wonderful devices. RCCL

1. Benoit DP, Ames KS. Diagnostic versus empiri-cal fi tting. Contact Lens Spectrum. 2010;25(4):12-13.2. van der Worp E, de Brabander J, Lubberman B, et al. Optimising RGP fi tting in normal eyes using 3D topography data. Cont. Lens Anterior Eye. 2002;11:1-5.3. Harris MG. Contact lens fl exure and residual astigmatism on toric corneas. J Am Optom As-soc. 1970;41(3):247-248.4. Mandell RB, Moore CF. A bitoric lens guide that really is simple. Contact Lens Spectrum. 1988;3(11):83-85.

5. Sarver MD, Kame RT, Williams CT. A bi-toric rigid gas permeable contact lens with spherical power eff ect. J Am Optom Assoc. 1985;56(3):184-189.6. Silbert JA. Rigid Contact Lens Correction of Astigmatism. In: Bennett ES, Weissman BA (eds.): Clinical Contact Lens Practice, 2nd ed. Butterworth-Heinemann, 2004.7. Silbert JA. Benefi ts of diagnostic fi tting for bitoric GP lenses. Optometric Management. 2007;42(2):54-59.8. Bennett ES, Sorbara L, Kojima R. Gas-Per-meable Lens Design, Fitting, and Evaluation. In: Clinical Manual of Contact lenses, 4th ed. Wolters Kluwer, Lippincott Williams & Williams, 2014:112-156.9. Keech P. The top 10 reasons to inventory RGPs. Contact Lens Spectrum. 1996;11(10):32-36.

GPs: ARE YOU MAKING GOOD USE OF DIAGNOSTIC FITTING SETS?


Storing and Maintenance of Diagnostic Sets

While it is possible to store diagnostic GP lenses in disinfect-ing solution, which also serves to improve on-eye wettability, it is not practical. Lenses that are not used regularly are more likely to adhere to the case and subsequently warp, as wet storage is likely to dry out via evaporation. Secondly, as disin-fecting solutions are not approved for use for more than a 30 days, lenses would have to be recleaned and placed in fresh solution regularly. In a busy practice, this is unlikely to happen; thus, storing diagnostic lenses dry is more practical. Lenses can be kept in fl at-packs, which take up very little space.

After a diagnostic lens has been used, it should be rubbed and rinsed with a lens cleaner and then disinfected before be-ing blotted and and stored dry. The CDC (Centers for Disease Control and Prevention) recommends hydrogen peroxide to disinfect GP lenses. While many practitioners suggest a fi ve- to 10-minute soak with an approved peroxide disinfection system such as ClearCare (Alcon) or PeroxiClear (Bausch + Lomb), proper disinfection generally requires a full four hours.

When a lens is to be reused, it should be fi rst cleaned using an approved cleaner (alcohol-based cleaners are very eff ec-tive for this purpose), rinsed and applied with a wetting or conditioning solution. Use of a conditioning solution is also recommended for six to 24 hours prior to delivery when dis-pensing a new set of lenses to the patient to ensure the base curve of the lens is properly hydrated.

In the rare case that a newly-dispensed GP lens is non-wetting, it is usually due to a hydrophobic zone on the lens caused by a waxy or pitch-like residue left from the lens blocking process. This can be readily remedied by cleaning the lens in-offi ce; the author recommends FluoroSolve (Para-gon), which dissolves waxy residue to enable tears to spread more eff ectively on the lens surface. The FluoroSolve should then be rinsed off and the lens cleaned and hydrated using an alcohol-based lens cleaner and conditioning solution, respec-tively, before re-insertion. If FluoroSolve is not available, an alcohol-based cleaner like as Mirafl ow or a generic equivalent can be used alone to restore the lens surface.


Specialty GP lens fitting tools, anytime and anywhere

fit-boston.com

Experience the website now! Scan this QR code on your device

and watch a video on what fit-boston.com has to offer.

Educational materials at your fingertipsThe Boston website offers a variety of educational materials and videos for the specialty lens fitting practice. Bookmark fit-boston.com and make it your “go to” resource for specialty GP lens information.

“Correction of Keratoconus with GP Lenses” A Guide to Scleral Lens Fitting Scleral Lens Fitting Videos Scleral Lens Fitting Scales

© 2015 Bausch & Lomb Incorporated. Boston and Bausch + Lomb are trademarks of Bausch & Lomb or its affiliates. US/BNL/14/0012b

RCCL0515_BL Boston.indd 1RCCL0515_BL Boston.indd 1 4/23/15 2:19 PM4/23/15 2:19 PM


Visual freedom, better quality of life and—in many cases—im-proved quality of vision are just some

of the benefi ts many wearers gain from contact lenses as compared to spectacles. With the ongoing refi nement of contact lens designs, practitioners now have more op-tions than ever to fi t even the most astigmatic presbyope or severe case of dry eye. Technology has evolved in tandem with the lenses them-selves, offering more advanced lens design and fabrication methods. This article addresses how to-day there truly is a lens for every patient.

SOFT LENSES

Lathe-cutting of custom soft toric and soft toric multifocal lenses was fi rst introduced with the approval by the Food and Drug Adminis-tration of the Defi nitive 74 sili-cone hydrogel lens material from Contamac. This process results in highly oxygen permeable lenses in practically any lens parameter. One relatively new example of this design is the Intelliwave multifocal toric (Art Optical), a center-near simultaneous vision soft lens with a multi-aspheric front surface for the correction of vision at all distances. This lens is an aberration-control design that can be fi t empirically.

The C-Vue Advanced HydraVue toric multifocal (Unilens) is an-

other example. Replaced monthly, it can be made in virtually any lens parameter. Eye care practitioners can also specify the base curve radius, overall diameter, sphere power, cylinder power and axis, add power and zone size.

New innovations in custom soft lens designs are not limited to the astigmatic presbyopic patient. Recently introduced custom soft keratoconic designs such as the KeraSoft IC (Bausch + Lomb) and NovaKone (Alden Optical) offer a made-to-order lens option avail-able in almost every conceivable power and cylinder axis. Kera-Soft is available in the Defi nitive silicone hydrogel material (Art Optical) with aberration control optics, while NovaKone uses a 54% hydrogel material. A quarter-ly replacement schedule is recom-mended for both lenses.

SCLERAL LENSES

Scleral lens use has continued to increase in recent years as a result of the high quality vision, lens sta-bility and comfort they provide for patients with irregular corneas and dry eye. Although the original de-sign has been available for decades, new trends include the develop-ment of varying diameters, materi-als and back surface geometries.

There are several new designs of note on the market. The Zenlens (Alden Optical) is available in both prolate and oblate designs with

either a 16mm or 17mm diameter. With this lens, practitioners are able to modify a single parameter (i.e., base curve, limbal clearance curve or peripheral curves) at a time. Toric peripheral curves can be ordered, as well as a front sur-face toric correction if needed.

The Europa Scleral (Visionary Optics) is a second-generation Jupiter scleral lens design with a large optical zone, mid-peripheral reverse curve and an enhanced haptic profi le for a better lens-to-sclera fi tting relationship. It is indicated both for irregular cornea correction and for patients with ocular surface disease.

Tru-Form Optics has the Digi-Form 15mm scleral lens which is available in fi ve primary designs for patients with either keratocon-ic, LASIK, RK, post-corneal graft or healthy corneas, as well as toric and quadrant-specifi c versions. The DigiForm 18mm diameter ver-sion incorporates laser markings on the front surface correspond-ing to the fi tting zone of the back surface.

ABOUT THE AUTHOR

Dr. Bennett is a professor of

optometry and assistant

dean of student services

and alumni relations at the

University of Missouri-St.

Louis College of Optometry.

He is also the executive director

of the GP Lens Institute.

Options Abound: A 2015 REPORT on

Custom Contact Lenses



Keep abreast of new developments in lenses and related technology that can strengthen your practice.

By Edward S. Bennett, OD

Peripheral toricity is also an important and increasingly popular feature of the newer scleral lens de-signs. The Custom Stable Elite lens (Valley Contax) is one such design.

Of course, scleral contact lenses are not just for compromised eyes; an increasing number have been introduced for astigmatic and presbyopic patients as well. These include the Onefi t P+A lens for astigmatic patients and Reclaim HD aspheric front surface multi-focal for presbyopes, both from Blanchard Contact Lens. The Elara Scleral (Visionary Optics) is an-other example of a scleral lens with a prolate design that has clinical applications for both healthy eyes and dry eye patients.

GAS PERMEABLE

MULTIFOCAL LENSES

The introduction of front surface aspheric multifocal or aspheric-concentric combination designs, capable of providing high add powers, has made GP multifocals the “go-to” lenses for presby-opes interested in clearer vision. The MPower lens (Art Optical), a simultaneous vision multifo-cal design, uses anterior surface eccentricity control to provide an extreme power change generated within the lens' central 5mm of the lens.

New progressive segmented, translating GP multifocal designs have also been introduced as well that allow not only uninterrupted

vision at distance and near but also correction at all distances. The SpectraVue by Tangent Streak (Firestone Optics) multifocal lens has the distance correction in the upper section of the lens that combines with a crescent-shaped middle segment to provide a progressive intermediate power change, similar to a spectacle pro-gressive addition lens but without a limiting channel.

Several other relatively new GP multifocal lens designs provide the presbyope with vision correction at all distances. These lenses comple-ment other multifocal and translat-ing designs introduced in recent years, including the TriVA design from ABB Optical and the Expert Progressive lens (Essilor, Art Opti-cal), both of which can be ordered empirically based on refractive and anatomical information.

HYBRID LENSES

Hybrid contact lens designs also continue to improve. Problems with fi rst and second generation designs include limited oxygen transmission, tearing of the junc-tion between the center GP and soft skirt and a tight fi tting rela-tionship; more recent designs have since addressed these issues.

One example, the UltraHealth design (SynergEyes), uses a re-verse geometry vault system to accommodate a range of prolate and oblate corneas. In this lens,

Fig. 1. Innovations in software are also improving our ability to fi t

custom lenses. Here, an EyeSpace-created diff erence map of the Forge

orthokeratology design is used to successfully fi t a 4.5D myopic patient.

SPECIAL ISSUE:



the oxygen-permeable central GP section is joined to the peripheral silicone hydrogel skirt with a co-valent bond to minimize tearing. A second lens from the same compa-ny, the UltraHealth FC, is designed specifi cally for oblate corneas, including post-refractive surgery patients and patients with pellucid marginal degeneration. SynergEyes is continuing to work on solving the third issue.

CUSTOM TINTED LENSES

While tinted lenses are often con-sidered cosmetic in nature, patients with traumatic eye injuries or congenital iris anomalies can also benefi t from these custom designs. One company, Orion Vision, spe-cializes in custom tinting of exist-ing contact lenses supplied by ABB Optical and Alden Optical.

MYOPIA PROGRESSION

While off-label, interest has risen in the use of corneal reshaping contact lenses to slow myopia progression. Several studies on

young progressive myopes wearing orthokeratology lenses overnight indicated axial length growth was signifi cantly slowed in comparison to those who wore contact lenses and spectacles.1,2 Other research evaluating peripheral plus power soft lens designs found regular wear resulted in an average of 50% less myopia progression and a 58% reduction in axial length progres-sion, compared with non-periph-eral plus power soft lens wearers.3

Peripheral plus bifocal designs have also demonstrated an effect on myopia, albeit less signifi cant and with some vision compromise.4-6

LENS DESIGN SOFTWARE

In addition to the lenses them-selves, new software programs are helping eye care practitio-ners achieve more successful fi ts. Recently available in the US, EyeSpace imports data from the corneal topographer and uses this information to design a rigid lens. It has notable applications in de-signing specialty lenses. (Figure 1).

“I have been using EyeSpace for a variety of corneal reshaping patients,” says Michael Lipson, OD. “It has worked well to attain centration in some diffi cult cases. Using it to design corneal reshap-ing lenses adds a high degree of precision and control to the effect and predictability to the process.”

The use of three-dimensional mapping to help fi t scleral lenses is also gaining popularity, says Greg DeNaeyer, OD. “Corneo-scleral topography and 3D mapping will signifi cantly advance scleral lens fi tting. Rather than relying on guesstimates from diagnostic lenses, corneo-scleral topography and scleral lens fi tting software will allow practitioners to virtually fi t scleral lenses that are customized for each particular eye.”

The sMap3D corneo-scleral to-pography system (Precision Ocular Metrology) is one such example that uses a structured light ap-proach to obtain micro precision measurements of the cornea and sclera.

OPTIONS ABOUND: A 2015 REPORT ON CUSTOM CONTACT LENSES


Fig. 2a. The EyePrintPro design exhibits the mold

accompanied by the resulting lens shape (in green).

Fig. 2b. A model of the lens on the eye.


Developed by Christine Sindt, OD, and manufactured by AVT, EyePrintPro is another 3D mapping technology that creates a prosthetic optical shell unique to the shape of the patient’s eye (Figures 2a and 2b). “The EyePrintPro has given me the opportunity to fi t extremely diffi cult patients with success,” says Stephanie Woo, OD. “The 3D scanner used to create the lens enables the practitioner to achieve a near-perfect tear layer between the cornea and the EyePrint, which results in a precise fi t and great vision. You can also customize the EyePrint to incorporate decentered optics or prism within the lens, which gives the patient a truly unique and custom visual device.”

NO LIMITS

The introduction of innovative new designs, supported by highly

advanced software and manufac-turing technology, has resulted in exciting new materials and designs in practically any lens parameters for almost any patient who is inter-ested in contact lenses. This does not mean that further research is not warranted; rather, this is simply the next step, and we look forward to see what next year will bring. RCCL

The author wishes to acknowl-edge the following: Peg Achenbach, OD (SynergEyes), Josh Adams (Valley Contax), Greg DeNaeyer, OD, Richard Dorer (Blanchard Contact Lens), Cassandra Gordon (Visionary Optics), Mike Johnson (Art Optical), Michael Lipson, OD, Kelly McKnight (Unilens), Daren Nygren (Custom Craft Lens Service), Keith Parker (AVT), John Patterson (Orion Vision), David

Rusch (Firestone Optics/Diversifi ed Ophthalmics), Ann Shackelford (ABB Optical), Bill Shelly (Alden Optical), Jan Svochak (Tru-Form Optics), and Stephanie Woo, OD.

1. Cho P, Cheung SW, Edwards M. The Longi-tudinal Orthokeratology Research in Children (LORIC) in Hong Kong: A pilot study on refrac-tive changes and myopic control. Curr Eye Res 2005;30:71-80.2. Walline JJ, Jones LA, Sinnott LT. Corneal reshaping and Myopia Progression. Br J Ophthal-mol 2009;93:1181-1185.3. Holden BA. The future of myopia manage-ment with contact lenses: Where to from here? Possibilities and probabilities. Presented at the Global Specialty Lens Symposium, January, 2015, Las Vegas, NV.4. Walline JJ, Greiner KL, McVey ME, Jones-Jor-dan LA. Multifocal contact lens myopia control. Optom Vis Sci 2013;90:1207-1214.5. Holden BA, Sankaridurg PR, de la Jara P, et al. Decreasing peripheral hyperopia with distance centre relatively plus powered periphery contact lenses reduced the rate of progress of myopia: A 5 year Vision CRC study. E poster 6300, ARVO 2012.6. Anstice NS, Phillips JR. Eff ect of dual focus soft contact lens wear on axial myopia progres-sion in children. Ophthalmology 2011;118(6):1152-1161.

IN VISION CARE

2015

N T

& T

N T

& TNew

Tec

hn

ologies and Treatments

REVIEW OF OPTOMETRYEDUCATIONAL MEETINGS OF CLINICAL EXCELLENCE

SAVE THE DATE

For More Information: WWW.REVOPTOM.COM/PHILADELPHIA2015

SAN DIEGO, CA • APRIL 10-12 Up to 17 CE Credits

(COPE approval pending)

Chair: Paul Karpecki, OD Speakers: Douglas Devries, OD; Jeff Gerson, OD;Blair Lonsberry, OD

PHILADELPHIA, PA • NOVEMBER 6-8

Approval Pending

Administered by

Review of Optometry


1 CE Credit

(COPE Approval Pending)


CRITICAL MEASUREMENTS TO IMPROVE

SCLERAL LENS FITTING

Gathering as much data as possible can help

streamline the process and provide better outcomes.

By Jason Jedlicka, OD

Scleral lenses have always been a mainstay of a specialty contact lens practice, offering patients with irregular

corneas and severe ocular surface disease alike the chance to benefi t from lens wear. But the category has been enjoying a renaissance in recent years, as the evolution of scleral lens designs has given us more fi tting options—namely, standard and reverse geometry designs, toric curves in the landing and transition zones, and toric and multifocal optics—that in turn al-low us to offer these lenses beyond the core group of traditional scleral patients.

While this increase in scleral lens parameter options gives practitio-ners the ability to fi t a wider range of eyes, it may make perfecting the fi t itself more challenging. Technol-ogy, on the other hand, is provid-ing information that can help us fi t these lenses quicker and more accurately.

This article reviews some of the newer approaches to the evaluation and fi t.

THE LIMITS OF

DIAGNOSTIC SETS

Traditionally, scleral lenses are fi t using one or several diagnostic sets. Practitioners use accompanying fi tting guides based on keratometry readings, ocular surface health and patient history to select an initial diagnostic lens; alternatively, they can simply choose a lens from the middle of the set to start with and adjust their selection accordingly based on the amount of lens depth needed. Some scleral lens fi tters may opt to look at the profi le of the eye they’re fi tting and use their experience to tell them which lens is most appropriate.

These techniques, however, while sometimes accurate, are diffi cult to teach and unreliable overall. Kera-tometric readings provide little in-formation about the ocular surface, even when combined with ocular history such as a diagnosis of kera-toconus or surgical procedures. If blind-selecting a lens, practitioners face the issue of identifying the necessary depth adjustments—as-suming the fi tting set is appropriate for the eye shape to begin with.

Thus, a more appropriate measure-ment system is needed.

SELECTING A LENS

While scleral lenses, unlike corneal lenses, vault the cornea to rest on the sclera, it is still vital for the practitioner to understand the contours of the patient’s cornea to ensure adequate but not excessive vault, which, after allowing for lens settling, should be approxi-mately 150µm to 250µm centrally and then and taper back to eventu-ally land on the sclera just past the limbus. Inadequate vault can result in cornea/lens touch and associated problems, as well as diffi culty with lens removal due to capillary at-traction; excessive vault can inhibit oxygen fl ow, patient comfort and ease of application. Aligning a scleral lens properly also lessens

Dr. Jedlicka is a clinical assis-

tant professor at the Illinois

College of Optometry and

president of the Scleral Lens

Education Society.

ABOUT THE AUTHOR

034_RCCL0915_F4_CE.indd 26034_RCCL0915_F4_CE.indd 26 8/25/15 12:52 PM8/25/15 12:52 PM

the need for high prescriptions that may reduce visual acuity, which can occur especially when fi tting steep corneal lenses in keratoconus, for example. Corneal topography can be used to ascertain corneal diameter or horizontal visible iris diameter (HVID), corneal apex location and the sagittal height of the cornea at a 10mm chord.

Anterior segment depth mea-surements obtained using optical coherence tomography (OCT) or Scheimpfl ug imaging is another way to improve the fi t of a scleral lens. The initial fi tting process can be streamlined by use of OCT or Scheimfl ug imaging, as these instruments obtain objective measurements of the depth of the cornea and sclera out to nearly 15mm, thereby providing a known starting point for diagnostic fi tting. In addition, these images allow the fi tter to see the contour of the cor-nea and sclera, to help determine if a particular fi tting set may be more ideal than others. OCT can also be used to evaluate the success of a fi t at follow up by providing precise measurements of the tear reservoir and edge contour to the sclera after a period of wear, without having to remove or manipulate the lens on eye.

Other scleral imaging instru-ments provide information regard-ing scleral shape and toricity to determine whether a lens should be ordered with toricity in the landing zone. Below are some methods for obtaining these measurements.

• HVID. Because the scleral lens needs to vault the entire cor-nea and limbus, it must be large enough in diameter to land outside the corneal-limbal zone. Corneal diameter measurements can be obtained using a corneal topogra-pher—simply capture the topo-graphical map and use the corneal diameter measure on the display (Figure 1). Some topogra-phers may also offer the ability to measure HVID with a point and click line display. A handheld ruler (Figure 2), slit lamp reti-cule or slit lamp camera with measuring capa-bilities, as well as anterior segment OCT, can also be used to measure HVID.

• Corneal Shape. Evaluating corneal shape is a good next step in the scleral lens fi tting process. Knowing where the cor-neal apex is will allow you to choose a lens with the most appropriate shape to match the cornea. If the corneal apex is within the central 4mm of the cornea, a standard geometry lens should work well; if

the apex of the cornea is located outside the central 4mm, however, or if there are signifi cant elevations (e.g., Salzmann’s nodular degenera-tion) near the peripheral cornea, a reverse geometry lens design may be more successful (Figure 3).

• Sagittal Height. Another useful measurement to aid in the scleral lens fi tting process is corneal sagit-tal height. Found on many corneal topographers, it is the measure-ment between the geometric center of the cornea and the intersection of a specifi ed chord length—in this case, 10mm (Figure 4). Aver-age sagittal height from 10mm to

Release Date: September 2015

Expiration Date: September 1, 2018

Goal Statement: This course reviews meth-ods for capturing and interpreting essential measurements when fitting scleral lenses.

Faculty/Editorial Board: Jason Jedlicka, OD, and Greg DeNaeyer, 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: Dr. Jedlicka has no finanical interest in any products men-tioned. Dr. DeNaeyer is a shareholer of Precision Ocular Metrology and received royalty payments for the Europa lens.


Fig. 1. Corneal topography display

demonstrating a corneal diameter

of 12.19mm, confi rmed by manual

measurement of 12.2mm.

Fig. 2. HVID ruler for measuring horizontal

corneal diameter.

SPECIAL ISSUE:



15mm for all eye types is approxi-mately 2,000µm.1 Thus, by using the 10mm chord depth and adding 2,000µm for the sag of the 10mm to 15mm chord plus the desired vault, you can come very close to the proper sag of the lens needed.

Take the following example: a 10mm chord demonstrates a sagit-tal height of 1,906µm. Based on a desired initial vault of 350µm cen-trally, a diagnostic lens in a 15mm diameter should be 4,256µm (i.e., 1906µm + 2,000µm + 350µm for vault = 4,256µm starting point for a 15mm lens). If the lens to be fi t is larger than 15mm, the sagittal

height will need to be increased incrementally, as the larger area of eye surface to be covered will mean greater overall depth. In my experience, having reviewed several scleral fi ts in retrospect, I fi nd that an adjustment of approximately 300µm per millimeter of lens diam-eter is fairly accurate (i.e., 4,256µm + 600µm, for a 2mm diameter increase = 4,856µm sagittal height for a 17mm diameter lens).

Obtaining a cross-sectional im-age of the anterior segment using diagnostic imaging technology is another useful way to obtain a starting point for an initial diag-nostic lens. The software included in these instruments can provide measurements for a variety of pos-sible heights and widths (Figures 5 & 6), simplifying the initial lens selection process.

• Scleral Contour Measure-ments. Some instruments are capable of evaluating the shape of the sclera, which may help practitioners achieve a proper lens fi t. Figure 7 shows an image of a highly toric sclera obtained from the Eye Surface Profi le (Eaglet Eye), one of two such instruments (the other being the sMap3D by Precision Ocular Metrology; see “Virtually Fitting Custom Scleral Lenses,” p. 29). However, while these instruments provide more in-formation about the ocular surface than corneal topography, at this time they are so new that the data they provide cannot yet be applied universally to all scleral lenses with simple formulas or rules.

ASSESSING LENS FIT

Once the scleral lens is on the eye, OCT can be used to assess lens fi t by providing information on central vault, limbal clearance and landing zone in relation to the sclera. The amount of desired

CRITICAL MEASUREMENTS TO IMPROVE SCLERAL FITTING


Fig. 3. Corneal topography

demonstrating the apex of the

cornea located approximately 4.5mm

inferior to the corneal center. This

shape may be better fi t with a scleral

lens with a reverse geometry design.

Fig. 4. Three-dimensional display of corneal topography shows corneal sagittal

height measurement at 10.0mm of 1,906 microns.

Fig. 5. OCT image demonstrating a sagittal height of 3,760 microns at a 15mm

chord.

Fig. 6. Pentacam image demonstrating a sagittal height of 4,230 microns at a

chord of 14.64mm.



Virtually Fitting Custom Scleral Lenses

By Gregory W. DeNaeyer, ODThe sMap3D topographer (Precision Ocular Metrology) uses a structured light ap-proach for three-dimensional mapping to obtain measure-ments of the cornea and sclera with a 22mm maximum fi eld of view. The sMap3D takes multiple trian-gulated measurements using a single DLP pro-jector and two cameras positioned laterally on each side. Fluorescein is added to the patient’s eye, which is necessary for imaging the corneal and bulbar conjunctival surface. The patient is then instructed to gaze at a fi xated light straight ahead while the eyelids are opened as widely as possible with assistance from the practitioner or a staff member. The practitioner focuses the eye and captures the image. Two additional measurements with the patient fi xat-ing up and down are taken in succession.

The sMapPro software is able to stitch together the images taken in straight, up, and down positions to produce a three-dimensional model of the patient’s eye (Figure 1). Stitching is a necessary step to obtain maximum area of the sclera that is occluded by the lids despite the eyelids being held open. A stitched model is required for measurement of the vertical me-ridians to determine accurate toricity measure-

ments and over all sagittal depth value, which are used for custom fi tting.

The sMapPro software gives sagittal depth data at any specifi ed chord. Corneo-scleral to-pography and elevation maps can be evaluat-ed. Scleral toricity can also be calculated from any specifi ed radius from center (Figure 2). The virtual fi t screen allows the practitioner to send the data directly to Visionary Optics for analy-sis and design of a custom Europa Scleral lens. A diagnostic lens does need to be applied for over-refraction to determine fi nal lens power.

Alternatively, the practitioner can custom fi t the lens using the software’s virtual fi tting plots. sMapPro software allows for complete specifi cation of any lens parameter to virtually adjust for corneal and limbal clearance, as well as custom back surface toricity. The sMapPro recommends a starting base curve based upon any desired initial amount of central corneal clearance. Peripheral curve toricity is calculated based upon the patient’s maximum scleral toricity. The fi tting software adjusts peripheral curve widths to ensure limbal clearance. Figure 3 shows a virtual fi t of a Europa scleral lens for a patient with keratoconus.

Dr. DeNaeyer is clinical director of Arena Eye Surgeons in Columbus, Ohio, and a consultant to Alcon, Visionary Optics, Bausch + Lomb and Aciont. He is also the designer of the Europa scleral lens (Visionary Optics) and a shareholder for Precision Ocular Metrology (sMap3D).

FIg. 3. Virtual fi t scleral lens on a keratoconus patient.

Fig. 2. Scleral elevation map and toricity.

Fig. 1. Data from three eye positions is stitched together to form a 3D model.


central vault and limbal clearance varies somewhat from one lens de-sign to another, as well as from one fi tter to the next. Generally speak-ing, a settled scleral lens should have between 150µm and 250µm of central vault, which tapers down to a fraction of that (20µm to 40µm) over the limbus to eventual-ly land on the sclera. A scleral lens with excessive or inadequate vault, or one that lands on or inside the limbus, needs to be reordered with the appropriate adjustments made to fi x these defi ciencies. Keep in mind these parameters may change somewhat from initial ap-plication to a time several hours later as the scleral lens settles into the tissue.

With respect to limbal clearance, there is no “magic number”; rather, as long as some amount of clearance exists, the limbus should be able to tolerate the lens. Note, however, excessive limbal clearance may allow for conjunctival prolapse and possibly sectoral hypoxia due to a thick tear res-ervoir. Figure 9 dem-onstrates several OCT images of scleral lenses with varying degrees of

clearance over the limbal area.OCT imaging can also be used

to evaluate edge profi les. This is helpful in ensuring that the landing zone of the lens is acceptable in all quadrants. A scleral lens that is too fl at will demonstrate edge lift on OCT. This fl at edge will encour-age debris to accumulate under the lens and fogging of the vision over the course of the day. A scleral lens that is too tight will demonstrate an appearance of lens “digging in” to the conjunctival-scleral complex. This tightness will create discom-fort and redness over time, and

may have more signifi cant long-term effects on the ocular sur-face. OCT can be particularly helpful in comparing edge fi t along different meridians in help-ing to determine if toric landing curves might be helpful to improve a scleral lens fi t. Figure 10 shows

several edge profi les. Fitting scleral lenses in the past

has been more of an art than a sci-ence in many respects. The future of scleral lens fi tting fi gures to be more scientifi c, driven by precise ocular surface measurements and software that can customize a lens to the individual eye. In the im-mediate term, using the technology that is available will streamline the fi tting process while we wait for a technological revolution in scleral lens fi tting to occur. RCCL

1. Kojima, R. Eye shape and scleral lenses. Con-tact Lens Spectrum. April 1, 2013.


CRITICAL MEASUREMENTS TO IMPROVE SCLERAL FITTING

Fig. 7. Corneal and scleral topography

obtained with an eye surface profi ler

indicate a highly toric scleral contour.

Fig. 8. OCT images of an adequately vaulted scleral lens

(top) and inadequately vaulted scleral lens (bottom).

Fig. 9. OCT images of scleral lenses

over the limbus, demonstrating ideal,

inadequate and possible excessive

clearance.

Fig. 10. OCT images of scleral edge profi les.

The top image appears to have a proper

alignment to the sclera, the middle image is

loose and the bottom image is tight.


1. Which modern diagnostic lens selection method was uncommon 10 years ago?

a. Using Ks and the fitting guide. b. Starting in the middle of the fitting set. c. Using OCT to measure corneal sagittal height. d. Using direct observation of the corneal shape.

2. Which of the following statements is true?

a. Use of technology (i.e., OCT, corneal topography, scleral profilometry) is of little value when fitting scleral lenses.

b. Corneal topography can provide good information when fitting scleral lenses, even though the lens does not touch the cornea.

c. OCT can tell us much about the shape of the sclera. d. Scleral topographers have been around for many years, but they have never

been useful when fitting scleral lenses.

3. Horizontal visible iris diameter (HVID) can be measured by all of the following except:

a. Calipometery. b. A handheld HVID ruler. c. Keratograph 5 M topographer. d. Slit lamp reticule.

4. Which of the following is least influential when using a reverse geometry fit-ting set?

a. Pellucid marginal degeneration. b. Salzmann’s nodular degeneration with peripheral lesions. c. Keratoconus with an apex within the central 3mm of the cornea. d. Radial keratometry scars.

5. Which of the following statements about the cornea is false?

a. Sagittal height at 10mm is useful in determining an initial diagnostic lens. b. Sagittal height at 10mm is easily obtained from a corneal topographer. c. Sagittal height at 10mm is noticeably different for normal corneas versus kera-

toconus. d. Sagittal height at 10mm provides an estimate of the shape of the sclera.

6. OCTs are useful when fitting scleral lenses in all of the following except:

a. Measuring central vault. b. Measuring limbal clearance. c. Measuring lens power. d. Evaulating the lens edge–sclera relationship.

7. Which of the following statements is true?

a. Scleral contour measurements help us to know when to use a toric haptic. b. Scleral topographers provide information about scleral shape but not the

cornea. c. Scleral topographers are fully compatible with nearly all scleral lens designs

and have software built-in for lens design for most manufacturers. d. Scleral topography contour measurements tell us much about the ability to

obtain good tear exchange with a scleral lens.

8. Which of the following critical measurements for scleral lens fitting is least

available to practitioners at this time?

a. Corneal topographical shape. b. Corneal sagittal height at 10 mm. c. Scleral contour measurements. d. HVID measurement.

9. Why is the shape of the cornea useful information when fitting a scleral lens?

a. It tells you whether toric landing curves are needed. b. It tells you whether you need a lens that is standard or reverse geometry. c. It tells you whether the scleral lens is likely to make the corneal disease progress. d. It tells you whether you have enough vault with your initial diagnostic lens.

10. Which of the following is not a benefit of using technology (i.e., OCT,

corneal topography, scleral profilometry) to assist with fitting scleral lenses?

a. It instills patient confidence in the provider and the process. b. It allows technical support staff to help in the process. c. It allows you to auto-fit scleral lens designs using built-in software. d. It allows you to obtain objective readings of lens fit at follow up for better

monitoring.

CE TEST ~ SEPTEMBER 2015 EXAMINATION ANSWER SHEET

Critical Measurements to Improve Scleral Lens Fitting

Valid for credit through September 1, 2018

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

Last Name

Email

The following is your: Home Address Business Address

Business Name

Address

City State

ZIP

Telephone # - -

Fax # - -

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 111768, RO-RCCL-0915



Custom contact lens design is a constantly evolving fi eld, from the advent of GP lenses in 1978 to more

recent developments in ortho-keratology. Soft lenses in particular now feature expanded diameters, curvatures, thicknesses and sphere and cylinder powers, giving prac-titioners more options than ever to manage complicated prescriptions in a highly precise way. Expanded diameters enable practitioners to fi t both small and large corneas of patients who would otherwise drop out of contact lens wear due to comfort or fi t issues; base curve customization can also help with achieving great fi t. Powers for these lenses range from +/-50D, giving even the most nearsighted patients the ability to see. With contact lenses this versatile, we can expand the amount of patients that we can help to wear contacts.

LOYALTY PROGRAM

With any contact lenses—standard, toric or even multifocal—the key to a successful fi t is achieving the best vision, comfort and ocular health response possible for the patient. Doing so effectively builds patient loyalty, especially when developing a contact lens specialty practice. Candidates for custom soft lenses include those who are experiencing refraction, rotation or fi t issues in their current lenses due to corneal irregularity, par-ticularly high astigmatism, and GP

lens candidates who are concerned about experiencing discomfort in hard lenses. Astigmatic presbyopes are also well suited to wear custom soft lenses.

If the patient expresses dissatis-faction with the vision or comfort provided by their current lenses, try explaining that a customized lens may be more comfortable and provide better vision. When a patient sees you for their compre-hensive eye exam, and you have performed a careful refraction along with keratometry readings, this could lead you to recommend-ing custom lenses.

Take this scenario, for example: “Jane, I see why your vision is not as sharp with your current con-tacts. The lenses you are wearing now are a ‘one-size-fi ts all,’ mean-ing that the shape of the lens only comes in one curve. Thus, you may need another shape to fi t your eye properly. Also, your current lenses only correct most of your prescrip-tion, not all of it. A more custom lens may fi t your eye better and give you better vision.” Adjust-ing the prescription and selecting a custom lens better suited to the

patient’s unique corneal shape are two simple ways to earn patient loyalty.

Even if they have not previously worn contacts, most patients with high astigmatism are aware their prescription is high—in fact, they may have already been told they are not candidates for contact lens wear. So, present the possibility of wearing custom lenses instead: “I think you are a great candidate for contact lenses; however, you have a signifi cant amount of astigma-tism. It is more than most standard contact lenses have available. So, I would recommend a custom lens that corrects your entire prescrip-tion and fi ts your eye properly.” Once patients understand why they can’t wear standard contact lenses, yet they are very motivated to wear them, they have no problem trying a more custom design.

SUPPLY AND DEMAND

Many contact lens manufacturers use some sort of fi tting nomo-gram to design a lens. Typically, the patient’s keratometry values, refraction and horizontal visible iris diameter (HVID) are used to create a lens; however, if the HVID is not available, most laboratories can still create the lens.

HVID has become somewhat of a hot topic within the contact lens community, as about 26% of patients fall out of the average iris diameter range.2 Appropriate lens diameter is important for lens sta-bilization and centration; thus, an

A Lens for Every Eye: Custom Contact LensesSuccessfully fi tting hard-to-fi t eyes is key to growing your specialty lens practice.

By Stephanie L. Woo, OD

The GP Expert


Fig. 1. TruForm’s QuadraCone.

Ph

oto

: Matt K

au

ff man

, OD

032_RCCL0915_gpe.indd 32032_RCCL0915_gpe.indd 32 8/25/15 12:51 PM8/25/15 12:51 PM

inappropriate lens diameter can lead to excessive lens movement and discomfort, and subsequent patient dropout. This is due to the pressure of the lid-lens interaction, which causes the lens to move and rotate on the eye; increasing the diameter of the lens decreases the lid-lens interaction. Most custom lenses can be ordered through the manufacturer’s website, or by supplying the laboratory with the patients’ refraction and keratom-etry values directly.

CUSTOM GP LENSES

Soft lenses are not the only lenses that are improving: huge strides are being made in the GP lens in-dustry as well. One such example is the QuadraKone (TruForm Op-

tics), which features differ-ent quadrants that can be manipulated to be steeper or fl atter, depending on the patient’s needs. Keratocon-ic lenses sometimes have a bit too much edge lift, which can cause the lens to decenter and dislodge from the eye. Steepening one of the quadrants can help tuck the edge in for a more precise fi t (Figure 1).

Scleral lenses have also im-proved signifi cantly in a rela-tively small amount of time. Most manufacturers have a multifocal scleral design available for the presbyopic population. Some sclerals are also available in a front surface toric version, al-lowing residual astigmatism to be easily added into the prescrip-tion (Figure 2). Practitioners can also rely on notching, a popular method of maneuvering around conjunctival obstacles such as pin-gueculas and blebs, and corneal topographic mapping, to fi t scler-als more effi ciently. RCCL

1. Nichols J. Contact Lens Update 2012. Contact Lens Spectrum. Jan 2012.2. Davis R, Eiden B. Problem solving toric con-tact lenses. Contact Lens Spectrum. Feb 2013.

Go Further—Without Leaving Home

Expand your clinical skills and catch up on your CE

requirements, all from the

comfort of your own home.

Review offers nearly 100 hours of COPE-approved continuing

education — right now! It’s just a click away. Our extensive

library of exams runs the gamut from

keratoconus to fundus autofluorescence, and everything in between.

www.revoptom.com/continuing_education

2013_ce_housead_third.indd 1 8/29/13 12:22 PM

• Custom soft lenses provide excellent vision and fi t.• Ordering custom soft lenses is simple—many

manufacturers only require refraction and keratometry values.• The cost is often comparable to or even less than the

patient’s current lenses.• Most patients cannot be fi t anywhere but in your offi ce,

ensuring patient loyalty.

Clinical Pearls

Fig. 2. Scleral lens with front toric markings

and notch near pinguecula.

Ph

oto

: To

ny C

ap

ora

ll, OD

032_RCCL0915_gpe.indd 33032_RCCL0915_gpe.indd 33 8/25/15 12:51 PM8/25/15 12:51 PM

Many of us have read or heard practice manage-ment advice that goes something

like this: “If you want your pa-tients to do X, tell them Y.” For example, “If you want to have more patients purchase annual supplies of contact lenses, tell them the price is less per box if they buy eight boxes than if they buy only one.”

Sounds reasonable, doesn’t it? So, after hearing this suggestion, you return to your practice and mention it to your next patient. And either it works or it doesn’t. In either case—success or failure—the question becomes, what do you do next? Does this one result give you enough information from which to craft a new strategy? How much can you extrapolate from a single data point? Not much. No scientist would attempt to draw conclusions from a study with a sample size of n=1. But in business matters, we have a harder time seeing the shortcomings of such an approach.

If the patient responded the way you had hoped and agreed to the bulk purchase, a few factors will help you determine if this ap-proach is worth continuing or not. First, will your patient have a bet-ter or worse clinical outcome with a year’s supply of lenses on hand? Studies suggest that it will gener-ally be more favorable because pa-tient compliance is typically higher when they have more lenses at the ready. However, is that going to be the case for this particular pa-

tient, or will they be one of those outliers who hoard their lenses? Since this remains a possibility, if you choose to use this strat-egy your defi nition of “success” should include a system of checks and balances so that when lens hoarders return, you don’t make the same mistake.

Next—and in my view most importantly—make sure that viewing this as a successful strat-egy and thus worthy of routine use, doesn’t close the door to other strategies that may be even better. For example, what would happen if you presented the lenses to the patient and said,

“When you buy a year’s sup-ply of lenses, you will never run out,” but you never mentioned the discount? Do you think as many patients would take you up on your offer? Even if only 10% fewer did, what would the effect be on the increased revenue you’d generate by not offering a discount? Alternatively, don’t assume that the lack of a volume discount will lead to fewer sales. It can (and often does) lead to more, depending on how you present the situation.

STAY FLEXIBLE

The answers to these practice management questions will vary between different practices, and even between staff members in a single practice. There isn’t a single right or wrong answer—rather, in any case it is important simply to ask yourself, “What will we do if this works, and can we make it even better?”

Regardless of your plan of ac-tion, however, be wary of using industry benchmarks as your goals. This will help you avoid any potential issues with using varying defi nitions. Continuing with the same example, one doctor might

report that 10% of their patients purchase annual supplies, while a second doctor reports 90% of their patients do so. What is not recorded, however, is the fact that the fi rst doctor has a large base of specialty scleral patients and the second has a signifi cant popula-tion of millennials who buy their lenses directly from the practice’s website. Additionally, keep in mind that benchmarking typically demonstrates averages and reports of “what is,” not what could be—as such, they can be limiting. RCCL

Blinded by the Light?Just because something works once doesn’t mean that it always will, or that it could never be surpassed by something even better.


Out of the Box By Gary Gerber, OD

ASK YOURSELF, “WHAT WILL WE DO IF THIS WORKS, AND CAN WE MAKE IT EVEN BETTER?”

034_RCCL0915_otb.indd 34034_RCCL0915_otb.indd 34 8/25/15 10:35 AM8/25/15 10:35 AM

RO0715_Cooper Clariti.indd 1RO0715_Cooper Clariti.indd 1 6/30/15 11:33 AM6/30/15 11:33 AM

Hello Miru.Bye, bye blister pack.Introducing Miru 1day, the world’s thinnest package for daily disposable contact lenses.

Miru’s ultra lightweight 1mm thin package is about 1/8th the thickness of a traditional blister pack

lens is presented on a special disk, oriented correctly for proper insertion.

To learn more and request trials, please visit: miru.meniconamerica.com

©2014 Menicon America, Inc. Miru is a registered trademark of Menicon Company Ltd.

RCCL0315_Menicon.indd 1RCCL0315_Menicon.indd 1 2/23/15 11:15 AM2/23/15 11:15 AM

rccl - review of cornea and contact lenses · in lens cases rather than using new solution (55.1%)....

Documents