4. EYES

Note: Red eye is commonly seen in a MEPS exam and is always a diagnostic dilemma. Applicants will usually fluff it off saying it only happened last night. Take any enlarged and dilated eye blood vessels seriously. The main causes are as follows: (1) allergic conjunctivitis (2) Uveitis (3) dry eye (4) blepharitis (5) acute glaucoma (6) subconjuctival hemorrhage (7) trauma (8) corneal ulcer or infection (9) CL wear (10) overuse of eye drops. These will be discussed below.

a. Lids

(1) Current symptomatic blepharitis (373.0x).

Blepharitis is any infection or inflammation of the eyelids including the base of the eyelashes, (crusty eyelid look). There are a number of causes including allergies, infections, irritation, or even skin cancers. The best way to understand blepharitis is to understand the meibomian glands which are little oil-secreting cells lining both the upper and lower eyelids. Their secretions prevent dry eyes, (xeropthalmia) by keeping the tears from the lachrymal glands from evaporating too quickly. Dry eyeballs can rub off skin from the lids leading to tissue cell fragments blocking the meibomian gland openings at the base of the eyelashes. This causes the tiny meibomian gland secretions to thicken and plug up. This forms a hard painless nodule called a chalazion. The little oil glands anteriorly at the base of the eye lash can also become infected (usually Staph aureus) causing an acutely painful blocked infected nodule at the base of the eyelash called a hordeolum or stye. Remember the difference, a chalazion is a painless non-infected nodule more posterior on the lid, and a hordeolum is an inflammation anteriorly causing that “crusty eyelash” look. A hordeolum is an infection, a chalazion is not Regardless of the cause, any acute red-hot painful eye infection cannot be qualified until it is resolved. Hordeolum recurrence is common, but a chalazion usually resolves in 2-8wks on its own. Lastly, make sure a small eyelid nodule is not a basal cell carcinoma.

(2) Current blepharospasm (333.81).

This is like a prolonged wink of the eyes. The eye can stay closed for days, or only a quick twitch, resembling a tic ( r/o Tourette’s in this

case.) They also tend to have dry eyes and discomfort with sunlight. There are multiple causes, but always r/o a psychiatric component.

(3) Current dacryocystitis, acute (375.32), or chronic (375.42)

Dacryocystitis is an infection of the lacrimal sac as a consequence of nasolacrimal duct obstruction, usually by staphylococcal or streptococcal. Acute dacryocystitis takes the form of a large red-hot tender swelling just below the inner canthus (medial palpebral fissure) of the eye. Chronic dacryocystitis is the same swelling mass but not red and tender, although there usually are signs of chronic conjunctivitis. Definitive treatment for resolved acute dacryocystitis or chronic conjunctivitis is usually with surgery that creates a passage between the lacrimal sac and the nasal cavity (dacryocystorhinostomy).

(4) Defect or deformity of the lids or other disorders affecting eyelid function (374.4x, 374.50, 374.85, 374.89, 743.62), complete, or significant ptosis (374. 3x, 743.61), sufficient to interfere with vision or impair protection of the eye from exposure.

This includes dry eyes or xerophthalmia (372.53). Acute or chronic conjunctival or corneal xerosis can be disqualifying depending on etiology and the likelihood to interfere with military training/service. This can be a chronic complication from LASIK surgery where the creation of the corneal flap disrupts the tiny corneal nerves to the lacrimal gland so there is no tear film until the nerves grow back. This may take up to 3-4 months during which the patient will have dry gritty eyes unless he uses artificial tears. As discussed above (1), a blepharitis could develop as a secondary complication. Dry eye treatment will depend on the underlying cause and severity, and may be disqualifying. Dry eyes after LASIK usually resolves within 4 months so may not be disqualifying. There is a condition called DES or dry eye syndrome (DES) or keratoconjunctivitis sicca with a number of causes that results in chronic dry eyes that can cause tiny abrasions of the surface of the eyes which leads to corneal erosion, punctuate keratopathy, corneal ulcerations and neovascularization, cornea scarring, thinning and even corneal perforation. Mild to moderate cases can be treated with lubricants or artificial tears. When dry eye symptoms are severe, they can interfere with quality of life causing blurred vision or severe irritation to the point that they may not be able to perform their duties. About half of all CL wearers complain of

dry eyes. Soft and rigid gas-permeable contact lens damage the corneal nerve sensitivity which leads to decreased lacrimal gland tear production and dry eye. ● Eyelid problems include (1) Entropion: inward turning of the eyelid which can damage the cornea producing keratitis and/or ulceration. (2) Trichiasis is where the lashes grow inward and cause corneal irritation, erosion and ulceration. (3) Ectropian is where the lids fall away from the globe leaving an open space causing irritation and dryness.

(5) Current growths or tumors of the eyelid (173.1, 198.2, 216.1,

232.1, 238.8, 239.89), other than small, non-progressive, asymptomatic, benign lesions.

b. Conjunctiva

The conjunctiva is a clear membrane of epithelial tissue that covers the sclera (white part) of the eye and lines the inside of the eyelids, up to the outer edge of the cornea, and the cornea then goes on to cover the iris, pupil and anterior chamber. You can get infections of the conjunctiva (conjunctivitis) or of the conjunctiva and cornea (keratoconjunctivitis.

(1) Current acute or chronic conjunctivitis (372.1x, 077.0). Seasonal allergic conjunctivitis (372.14) DOES meet the standard.

You will often find “red eyes” in CL wearers during your exam. They usually say they are having a” little trouble with their contacts right now” But either Giant Papillary Conjunctivitis (GPC) or corneal neovascularization (see below) should also be ruled out. Look under their eyelids for small wart-like 0.3 mm papillae to r/o GPC. There is a condition called keratoconjunctivitis sicca or DES (Dry Eye Syndrome) see above (4) lid disorders.

(2) Current pterygium (372.4x) if condition encroaches on the cornea in excess of 3 millimeters, interferes with vision, is progressive, or a history of recurrence after any prior surgical removal (372.45).

In measuring a pterygium, remember the cornea’s edge is about right where you see the outer edge of the iris, and for all practical purposes you measure the length of the pterygium you see extending onto the iris. Pterygium is caused by sun, wind, and sand. But excess sun exposure can also result in a similar growth called pinguecula. A pinguecula is a yellowish white deposit sitting right next to the limbus in the inner corner of the eye where pterygiums start also, so don’t mix them up.

c. Cornea

The cornea is a clear 5 layer membrane that covers the iris, pupil and anterior chamber (space between the iris and the inside of the cornea, and extends out to to meet the conjunctiva which covers the rest of the sclera and inside of eyelids. Contact lenses (CL) cover the cornea. Remember, all CL are foreign bodies in the eyes. And wearers get lax in wearing and caring for them properly. There are 5 complications to look for in any applicant with CL and red eyes: (see (4) above): (1) GPC (2) neovascularization (3) corneal keratitis or ulcer (4) corneal abrasion (5) corneal edema

(1) Corneal dystrophy, degeneration or ectasia of any type (371.x), including but not limited to keratoconus (371.6x) of any degree.

Keratoconus is a progressive non-inflammatory degeneration of the cornea where it changes from its smooth convex dome shape to that of being coned shape. Because it is progressive with continued vision deterioration, it is generally is not waivered. A cylinder reading of 3.00 or more in a MEPS eye test is the first sign of possible keratoconus, and further examination with topography (corneal mapping) is recommended. K-readings also suggest possible keratoconus, and any K-reading over 45D (diopters) is suspect. MEPS examiners are always trying to find ways to physically diagnose keratoconus whenever they see a high CYL reading, but it is difficult. A history of frequent increases in an applicant’s astigmatism prescription is the first sign. Also, there is commonly a history of atopic dermatitis, eczema and asthma, and any condition causing frequent eye rubbing seems to aggravate or cause keratoconus. You might see Fleischer’s rings which are yellow-brown rings seen with the ophthalmoscope around the base of the cone, and Munson’s sign which is a bulging of the lower lid in downward gaze. The cone pushes the lower lid out in a small bulge as it tries to get

below the lower lid in looking down. Sometimes an optometry consult will report seeing pellucid marginal degeneration which is thinning of the outer edge of the cornea as if it was pulling in as a cone develops in the center of the cornea. Whether this is an early stage of keratoconus (forme fruste) or a separate disease of cornea ectasia is still in question. Either condition is disqualifying. Although, various types of treatment with rigid CL are being tried, these applicants should never have any LASIK/PRK procedures.

(2) History of any incisional corneal surgery including, but not limited to, partial or full thickness corneal transplant, radial keratotomy (RK), astigmatic keratotomy (AK), or corneal implants (Intacs®)

RK was the early forerunner of LASIK/PRK, and consisted of slicing small cuts in the cornea like wheel spokes to flatten the cornea and improve vision. Intacs is a newer supposedly less invasive cornea procedure where a small ring is implanted on the peripheral edge of the cornea to change the shape to correct vision. They are called intracorneal rings (ICRs) and can be readjusted as necessary. They are only used for mild nearsightedness (hyperopia). A newer procedure now being seen in MEPS called ICLs or phakic intraocular lenses where a small cut is made on the side of the cornea and a small polymer type of collagen lens is slid in right over the lens to correct the vision error. They are met to be permanent, but can be removed and adjusted as necessary. There are complications including infections, cataracts, increased IOP and symptoms such as halos, glare and diplopia. Visian ICL is a popular brand being used presently. But, since these procedures are new and have no track record, they are presently still disqualifying.

(3) Corneal refractive surgery performed with an excimer laser, including but not limited to photorefractive keratectomy (PRK) (HCPCS S0810), laser epithelial keratomileusis (LASEK), and laser-assisted in situ keratomileusis (LASIK)

(HCPCS S0900) (ICD-9 code for each is P11.7) if any of the following conditions are met:

(a) Pre-surgical refractive error in either eye exceeded a spherical equivalent of +8.00 or -8.00 diopters.

(b) Pre-surgical astigmatism exceeded 3.00 diopters.There is a form of astigmatism called “irregular” astigmatism (as compared to “regular” astigmatism) that is used as a bit of a catch-all term to describe any corneal irregularity that cannot be corrected with glasses and is very difficult to correct with laser surgery, and usually can only be corrected by gas permeable CL even after an applicant has had LASIK/PRK surgery. It is due to more complex irregularities which are bending the light entering the eye in too many directions to be effectively corrected with a spectacle lens. Hence, they cannot wear glasses (spectacles). In all CL users, always ask if they can wear glasses if they want to.

(c) For corneal refractive surgery, at least 180 days recovery period has not occurred between last refractive surgery or augmenting procedure and accession medical examination.

(d) There have been complications and/or medications or ophthalmic solutions, or any other therapeutic interventions such as sunglasses, are required.

Post-op complications usually resolve by 4 months after the procedure (e.g. haze, glare, star burst, halos, ghosts, double images, night vision difficulty, worsening refractive error, dry eyes (see above) and infections (blepharitis and conjunctivitis). Use of ophthalmic solutions required at the time of the MEPS evaluation is disqualifying. ● There is a category of complications called “ablation defects” such as central islands, decentered ablations, underablation, and irregular astigmatism and are due to technical errors in the delivery of the excimer laser energy itself, and results in poor vision quality. “Irregular astigmatism” is due to several possibilities such as flap complications, scarring or just poor quality laser ablation, and unlike regular astigmatism, cannot be corrected with glasses, but can usually be corrected with gas permeable CL as an aftermath of their laser surgery.

(e) Post-surgical refraction in each eye is not stable as demonstrated by at least two separate refractions at least 1 month apart, with initial refraction at least 90 days post-procedure, and the most recent of which demonstrates more than +/- 0.50 diopters difference for spherical vision and/or more than +/- 0.50 diopters for cylinder vision.

If there are insufficient post-op docs, and it has been at least 90 days post-op, consider getting two manifest refractions (MR), 30 days apart. However, if you get the first MR, and the SPH and CYL both are 0.50 or less, and at least 6 months post-surgery, this suggests stable results from their surgery. MR is “manifest refraction, done with multiple lens while the examiner asks the patient to choose the best lens for his vision.

LASIK versus PRK: PRK is actually a forerunner of LASIK where the laser energy is applied directly to the surface of the cornea (no flap is made). The drawback is slower healing time with pain since the surface contains the corneal pain fibers, and is surgically disrupted, hence longer painful healing times. LASIK on the other hand does not disrupt the surface as a flap is made, and the laser energy is applied to the layers beneath the flap, and then closed. No pain fibers are interrupted, and healing is much faster. The military initially avoided LASIK since pilots exposed to high G-loads in combat aircraft. were experiencing the LASIK flaps coming lose. However, after years of study, the Air Force has decided to change their long-standing policy which disqualified applicants who have had LASIK surgery from flight and navigator training. However, they do recommend Wave Front Guided procedures (WFG-PRK and WFG-LASIK). The change became effective May 2007. Additional “flap complications” are mentioned above (d).

(4) Current or recurrent keratitis (370.xx)

Keratitis is a broad term use to define a wide variety of corneal infections, irritations, and inflammations. Symptoms of acute keratitis are photophobia and pain. Sometimes the cornea loses its sensitivity from trauma or surgery, then there is a high risk of corneal ulcers. If you see a history of keratitis, look for an etiology. In the MEPS population, staph or herpes infections are common after simple trauma such as a scratch or abrasion of the cornea (see herpes keratitis below). Leaving soft CL in overnight increases the risk of keratitis by 10 to 15 times. CLARE (Contact Lens Acute Red Eye) is a non-

ulcerative sterile keratitis associated with colonization of Gram-negative bacteria on contract lenses. Miscellaneous causes include antibiotic reactions, conjunctivitis, “dry eye,” and autoimmune disease, among other things. You can have superficial keratitis that usually resolves without any sequalae, or deep keratitis into the cornea that commonly leaves permanent scars that affect vision, or even perforate the cornea causing corneal ulcers. If you see a suspect acute keratitis, a consult is required for a slit lamp exam and corneal fluorescein test. The definition of “recurrent” is ill defined; however, any more than one well documented episode of keratitis should be taken seriously.

(5) Documented herpes simplex virus keratitis (054.42, 054.43).

Herpes keratitis is a nasty infection in the eye as it tends to be recurrent because it resides permanently in the corneal tissue itself, as well in the ganglion of the trigeminal nerve (CN-V) thus always being able to serve as a source of recurrent infections with such triggers as stress, systemic infections, sunlight exposure, menstruation, CL wear and eye injuries. It is usually the HSV-I responsible, since HSV-2 is mostly transmitted sexually. There are various clinical forms of herpes keratitis such as infectious epithelial keratitis, neurotrophic keratopathy, necrotizing stromal keratitis, immune stromal keratitis (ISK), and endotheliitis, and each can affect all levels of the cornea. HSV keratitis is the most frequent cause of corneal blindness in the U.S. and the leading indication for corneal transplants.

(6) Current corneal neovascularization, unspecified (370.60), or corneal opacification (371.00, 371.03) from any cause that is progressive or reduces vision below the standards prescribed in this Instruction.

Corneal neovascularization is a cry from the cornea for oxygen which has been cut off by prolonged CL use. The cornea normally gets it oxygen from the air, and this is a desperate attempt to get oxygen by growing new blood vessels giving a “red eye” look. GPC (giant papillary conjunctivitis) discussed above is another cause for red eyes stemming from prolonged CL. Don’t over look “red eyes” in applicants with CL just because they tell you they forgot to take them out last night. Either get a consult or recheck them at a later date]

(7) Current or history of uveitis or iridocyclitis (364.00-364.3).

This will show up in MEPS as “red eyes.” Additionally, always check for a stiff back or back pain – see Section 17a - Ankylosing spondylitis or other inflammatory spondylopathies]

d. Retina

(1) Current or history of any abnormality of the retina (361.00-362.89, 363.14-363.22), choroid (363.00-363.9) or vitreous (379.2x).

Retinal degeneration leads to retinal detachments (RD). One early risk factor often reported by optometrists is lattice degeneration where the retina is stretched out very thin on the edges easily leading to holes & tears. The vitreous fluid leaks through these breaks and further separates the retina from the posterior choroid layer leading to RD. Risk factors are a family history of RD, old eye trauma, and high myopia (extremely nearsighted – this is one reason why ERE of over -8.00 diopters is disqualifying). 8% of the general population has lattice changes, which doubles to 15% in high myopia. In reviewing ERE for a waiver, the SWA usually asks for a dilated retinal exam done by an optometrist or ophthalmologist.

e. Optic Nerve

(1) Any current or history of optic nerve disease (377.3), including but not limited to optic nerve inflammation (363.05), optic nerve swelling, or optic nerve atrophy (377.12, 377.14).

Optic nerve disease usually shows up poor vision that cannot be corrected with CL or spectacles, and if progressive, will result in blindness. On examination you will see various forms of cupping, swelling and atrophy. Tumors and head injuries are an important cause, with traumatic brain injuries (TBI) being the most common cause of optic nerve disease in the MEPS population. GOND (Glaucomatous Optic nerve Disease) is secondary to glaucoma. There is a broad category called Toxic Optic Nerve Disease caused by a large number of poisonous substances, drugs, nutritional deficiencies, metabolic disorders and radiation. This includes smoking, alcohol, barbiturates, DDT, lead and a number of prescription drugs including propranolol, as well as diabetes and thyroid disease. There is Ischemic Optic Neuropathy (ION) seen in over-40 applicants due to diabetes, HTN and ASVD. The Swinging Flashlight Test for a Marcus

Gunn pupil which is a sign of optic nerve disease is described under H.(5) below (Abnormal Pupils)] .

(2) Any optic nerve anomaly.

Optic nerve hypoplasia is the most common congenital optic disc anomaly, and is usually bilateral. The optic disc is the anatomical location of the eye’s “blind spot,” the area where the optic nerve and blood vessels enter the retina. With optic nerve hypoplasia, you see small hypoplastic pale disc. In MEPS the tip off is poor vision that can not be corrected. Optometrist will report an abnormal increase in the cup-to-disc ratio due to the small pale disc representing the optic nerve with the central normal sized cup. ● The cup-to-disc ratio compares the diameter of the smaller center "cup" portion with the larger outer diameter of the optic disc. A good analogy to better understand the cup-to-disc ratio is the ratio of a donut hole to the donut. The hole represents the cup and the surrounding area the larger disc. If the cup fills 1/10 of the disc, the ratio will be 0.1 and is quite normal. If the ratio is 1.0, this is severe “cupping.” If it fills 7/10 of the disc, the ratio is 0.7, still abnormal. A 0.5 ratio means that the cup occupies 50 % of the larger outside disc area. (Normal ratios are 0.2 to 0.3) An acquired optic nerve defect that causes a large cup-to-disc ratio is glaucoma, which is due to an increase in the IOP, and produces increased pathological cupping of the optic disc by pushing in on this central cup, making it larger (The pink rim of the disc contains nerve fibers, the white cup is a pit with no nerve fibers). As glaucoma advances, the cup enlarges until it occupies most of the disc area killing the small optic disc nerve fibers, finally the cup may occupy most of the disc area. Any cup to disc ratio greater than 0.6 to 0.7 is glaucoma suspect and needs further evaluation.

f. Lens

(1) Current aphakia (379.31, 743.35), history of lens implant (pseudophakia is an artificial lens implant usually for a cataract or loss of lens do to trauma) (V45.61, V43.1) (CPT 66982-66986), or current or history of dislocation of a lens (379.32-379.34, 743.37).

(2) Current or history of opacities of the lens (366.xx), including cataract (366.9).

Congenital cataracts are seldom progressive, but may cause nystagmus and/or lazy eye (amblyopia), this is probably waiverable if there is no vision reduction, and has been stable, Cataracts due to trauma in childhood (pediatric cataracts) are progressive and more likely to be disqualifying.

g. Ocular Mobility and Motility

(1) Current or recurrent diplopia (368.2).

Diplopia is caused by many things, including cataracts, strabismus, diabetes, and various brain disorders like tumors. In MEPS it is most likely due to a complication of LASIK/PRK surgery, or strabismus, particularly with fatigue from activities such as prolonged reading. Diplopia is a symptom and the underlying cause needs to be evaluated.

(2) Current nystagmus (379.5x) other than physiologic “end-point nystagmus.”

Nystagmus is a neurological reflex, and like all abnormal reflexes, a broader neurological disorder should be looked for. Nystagmus is a slow movement in one direction with a quick alternating “jerk-like” movement in the opposite direction called saccadic movement. It is involuntary and part of the vestibule-ocular reflex (VOR), Nystagmus is described in terms of the direction of its quick phase, if it “jerks” to the right and slowly alternates back to the left, it is called a “right-beating” nystagmus. You can also have downbeat and upbeat nystagmus and combinations. The direction of the fast “saccadic” jerking movement is the name of the nystagmus. The problem is to differentiate a pathological nystagmus from a physiologic nystagmus. A physiological nystagmus is also called “end-point nystagmus” because it occurs when the examiner tells the applicant to follow his finger, and he quickly moves it laterally beyond 40 degrees (way over to the side) and you see a low-amplitude horizontal nystagmus with the rapid phase (saccadic jerking) directed laterally. It usually does not occur until the eyes have been held in this position for a few seconds. The intensity is lower and more importantly, it is not associated with other ocular motor abnormalities. If there is any doubt, further evaluation by a neurologist or ophthalmologist should be considered.

(3) Esotropia (378.0x), exotropia (378.1x), and hypertropia (378.31): (These are all forms of strabismus)

Any degree of strabismus is now disqualifying. Esotropia is “cross-eyed” or turned inward, and exotropia turns the eyes outward, just opposite of esotropia. Hypertropia is where one eye looks upward and is usually due to a CN-4 palsy affecting the superior oblique eye EOM. Any strabismus that takes over 40 prisms to correct is severe. All forms of strabismus can cause “lazy eye” or amblyopia with a significant loss of vision and/or diplopia. In MEPS, it shows up with alarge difference in the corrected vision between the two eyes. If the strabismus or any other condition causes a large difference in corrected vision (50 or more between the two eyes), MEPS should order an optometry consult. If you recommend a wavier for strabismus, document presence or absence of diplopia, VF defects or any other eye conditions.

h. Miscellaneous Defects and Diseases

(1) Current or history of abnormal visual fields (368.9) due to diseases of the eye or central nervous system (368.4x), or trauma.

Visual fields (VF) loss can be due to diseases of the eye, optic nerve or brain and all are serious. VF reduction is also a part of glaucoma evaluation, and should always be looked for in any glaucoma suspect. A screening exam is called confrontational field testing. To perform the test, the individual occludes one eye while fixating on the examiner's eye with the non-occluded eye. The patient is then asked to count the number of fingers that are briefly flashed in each of the four quadrants. This method is preferred to the wiggly finger test since the applicant can give contrary responses. This is a screening test and simply answers the question: is the peripheral visual field affected? If you find a possible loss, they should be referred for a consult and more formal VF testing. Common problems of the visual field include scotoma (area of reduced vision), hemianopia (half of visual field lost), homonymous quadrantanopia (involving both eyes) and bitemporal hemianopia .

(2) Absence of an eye (V43.0, V45.78), clinical anophthalmos, unspecified congenital (743.00) or acquired, or current or history of other disorders of globe (360.xx).

(3) Current unilateral or bilateral exophthalmoses

(376.21-376.36). (Proptosis)

The most common cause of exophthalmos is Grave’s disease which is disqualifying in itself. In MEPS, you could also see unilateral proptosis due to periorbital cellulitis, and less likely undiagnosed retroorbital tumors. After Grave’s disease, you will mostly see congenital or familial bulging without any discernible cause. Of concern with exophthalmos are the side effects and complications caused by the bulging eyeballs. Besides the mechanical problems of pain, diplopia, red eyes, and dry eyes (due to failure of lid closure), there can be a progressive loss of vision, and difficulty with moving the eyes. All of these factors have to be assessed in terms of symptoms that might interfere with military training/service. Exophthalmos can be measured, (Hertel instrument), it measures the distance from the lateral orbit rim to the anterior cornea surface, and should be 19 mm or less (most are in the 16-18 mm range).

(4) Current or history of glaucoma (365.xx), ocular hypertension, pre-glaucoma (365.0-365.04), or glaucoma suspect.

Glaucoma diagnosis is a combination of three things: (1) Elevated IOP over 21mmHg, (2) Secondary optic nerve head damage, (3) Visual field (VF) loss. You have to have all 3 to make the diagnosis. Otherwise, you have one of the other three conditions listed above. Pre-glaucoma and ocular hypertension can both have elevated IOP without VF loss or optic nerve head damage. Glaucoma suspect also includes having risk factors such as a difference of 4mmHg or more in the IOP readings, and/or excessive hyperopia with a high sphere over +8.0 (farsighted or “short eyes”), and a family history. With any elevated IOP, order an OPTOM consult with VF testing and a slit lamp exam for “angle measurement.” For a discussion of optic nerve head damage due to glaucomatous “cupping,” see Optic Nerve ( e.(2) above. ● Occasionally, you will see reference to Pigment Dispersion Syndrome in various optometry/ophthalmology reports. This should be treated as a glaucoma suspect (normal IOPs), and therefore is disqualifying. This is usually a harmless condition caused by congenitally smaller space between the pigment in the posterior iris that can be jarred lose by abrasive trauma rubbing against the zonula fibers of the lens. This frees up pigment particles that can flow into the angles creating a blockade to aqueous outflow. This results in an elevated IOP, particularly after vigorous exercise of or pharmacological dilation causing classic pigmentary glaucoma. They will go on to develop optic atrophy and VF loss from the resulting glaucoma.

(5) Any abnormal pupillary reaction to light (379.4x) or accommodation (367.5x).

Normally, pupils react (i.e. constrict) equally and briskly. Lack of the pupillary reflex or an abnormal pupillary reflex can be caused by optic nerve damage, CN-III oculomotor nerve damage, and drugs. The various pathways are complicated, and all you are doing is a screening examination. However, if you find both pupillary reflexes normal in your examination, do not test for accommodation as it is only abnormal when there is an abnormality of the pupillary reflex. An examination of pupillary function includes inspecting the pupils for equal size (2 mm or less of difference may be normal), a round and regular shape, reactive to light, and direct and consensual accommodation.

These steps can be easily remembered with the mnemonic PERRLA (D+C): Pupils Equal and Round; Reactive to Light and Accommodation (Direct and Consensual).

Under normal conditions, the pupils of both eyes respond identically to a light stimulus, regardless of which eye is being stimulated. Light entering one eye produces a constriction of the pupil of that eye, the direct response, as well as a constriction of the pupil of the unstimulated eye, called the consensual response. Comparing these two responses in both eyes is helpful in locating a lesion. Accommodation is when you hold your finger about 10 cm from the applicant’s nose and ask them to alternate looking into the distance and at your finger. The pupils should constrict when looking at your finger.

If bilaterally small pupils constricts poorly to light but normal to accommodation, this is an Argyll Robertson pupil, and has many causes, but always r/o tertiary neurosyphilis (very rare now). The main substances that cause abnormally small pupils are alcohol and opioids (Heroin, morphine, codeine, and narcotic analgesics such as hydrocodone and oxycodone. Illegal substances that cause large pupils are LSD, cocaine, amphetamines, mescaline and psilocybin mushrooms. If you see particularly large pupils in room light, consider Bene Dilitatism – see below under Night Blindness. Then there is the Marcus Gunn pupil or RAPD (Relative Afferent Papillary Defect) that signals optic nerve damage. (RAPD never causes anisocoria (see (6) below) because there is no imbalance of the efferent pathway from the brain back to the pupil.)

Since a relative afferent papillary defect (RAPD) means retinal or optic nerve atrophy (CN I), it is important you understand how to do a "swinging flashlight test". In a person with two normal-looking pupils, if we shine the light on one eye, the pupil of that eye constricts immediately; then if we swing the light to the other eye, that pupil also constricts immediately. However, if one eye has retinal or optic nerve disorders, then if we first shine the light on the normal eye, that pupil constricts, and then shine the light on the bad eye, instead of constricting the pupil dilates immediately (Marcus Gunn pupil).

(6) Asymmetry of pupil size greater than 2mm.

Unequal pupils is called anisocoria, (Any aniscocoria greater than 2mm is disqualifying.) But, either way, both pupils still should react to light briskly and equally. If not, it is important to establish which of the two pupils is reacting abnormally. If the smaller pupil (miosis) is abnormal, it will not dilate in a dark room. This is a defect in the sympathetic fibers that cause dilatation as seen in a Horner’s syndrome. If the abnormal pupil is the larger one (mydriasis), then shining your light into it will NOT cause it to constrict. This suggests a CN III (Occulomotor) parasympathetic palsy or defect, possibly from a globe injury i.e. blow-out fracture. In MEPS you may see this in a history of head injury. If you find a ptosis, an interesting fact is the pupil on the side of the ptosis is the abnormal pupil. If it is a smaller pupil, then you have a Horner’s syndrome, if it is a larger pupil, then you have occulomotor palsy (Both can cause ptosis). By the way, there are many causes of a Horner’s syndrome, and has to be worked out. A quite benign cause of anisocoria is Aide’s pupil with a one-sided enlarged pupil seen in women 20 to 40 years of age, thought to be due to some unknown viral infection, hence no treatment other than just prescribing reading glasses. REMEMBER, in TBI, anisocoria is most likely due to CN III injury due to various complications from the injury. The involved pupil might be dilated (mydriasis) or constricted (miosis). Also, you will not uncommonly see a remote eye injury from a “stick in the eye” when an applicant was younger, and fails to tell you about his childhood accident. In MEPS, anytime you see unequal pupils, find out why]

(7) Current night blindness (264.5, 368.6x). Nyctalopia

This is very difficult to evaluate, and has to be done by asking a few questions. Ask if dusk is bothersome, car headlights cause glare, and how long does it take to adjust to a dark movie theater? “Do you see shadows at night, or see stars easily?” Some will admit they have started to wear glasses to drive at night. By far, the most common reason of nyctalopia seen in MEPS is from LASIK or PRK procedures in which the surgical manipulation of the cornea damages it’s structural integrity that causes abnormal light-scattering, Nearly all post-op patient’s have this for a while, but it should slowly resolve by 3-4 months. If you see this complication noted in the post-op visits, be more vigilant in checking their present symptoms. If you find no indication from these questions of any night blindness, then notate “Night blindness NIBH.” (not indicated by history) The most common cause of permanent nyctalopia is retinitis pigmentosa, a rare genetic disease (1:30,000) of progressive retinal dystrophy. Less likely it can be a vitamin A deficiency, or due to peripheral cataracts, or pathological myopia – very high minus sphere readings. There is a condition called “Bene Dilitatism” where there is only slight damage of the optic nerve causing widened pupils on a normal basis due to the inability for the optical nerves to register a correct amount of light. On exam, they have wider pupils than normal for the amount of room light, they have pain in brightness (wear sunglasses) and poor vision at night.]

(8) Current or history of intraocular foreign body (360.50-360.69, 871.x).

(9) Current or history of ocular tumors (190.0, 190.8-190.9, 198.4,

224.0, 224.8-224.9, 234.0, 238.8, 239.89, V10.84).

(10) Current or history of any abnormality of the eye (360) or adnexa (376, 379.9), not specified in the above subparagraphs, which threatens vision or visual function V41.0-V41.1, V52.2, V59.5).

This includes “asthenopia” which is ill-defined recurrent weakness or easy fatigue of the eyes associated with pain, headache or disturbance of vision, etc.

a. Current distant visual acuity of any degree that does not correct with spectacle lenses to at least one of the following (367):

Whenever there is still a difference of 50 or more between the DVA between the two

eyes after correction, get an optometry consult, e.g. DVA CORR OD 20/30 OS 20/80

(1) 20/40 in one eye and 20/70 in the other eye (369.75).

(2) 20/30 in one eye and 20/100 in the other eye (369.75).

(3) 20/20 in one eye and 20/400 in the other eye (369.73).

To be profiled as an E-1 profile with DVA, an applicant has to have uncorrected vision of 20/200 or better, and both eyes have to correct to 20/20. The above examples would be E-2 profiles.

b. Current near visual acuity of any degree that does not correct to 20/40 in the better eye (367.1-367.32).

c. Current refractive error (hyperopia (367.0), myopia (367.1), astigmatism (367.2x)), in excess of -8.00 or +8.00 diopters spherical equivalent or astigmatism in excess of 3.00 diopters. If the SE is in a gray area of +/- 7.50 to 8.50, always get an OPTOM consult with a retinal exam. For any CYL 3.0 or more, corneal mapping (topography) to r/o keratoconus is suggested. SE (spherical equivalent) is a way to describe the “average” error in the curvature of the cornea

and is simply algebraic sum of the SPH plus ½ of the CYL. e.g.

sph +6.50 and cyl -2.40 algebraically gives you a SE of +5.30

d. Any condition requiring contact lenses for adequate correction of vision, such as corneal scars and opacities (370.0x) and irregular astigmatism (367.22).

If the applicant tells you they wear CL, always ask them if they can wear glasses (spectacles) if they want to. Also, ask if their vision prescription is stable, or does it change every 6 to 12 months.

e. Color vision (368.5x) requirements shall be set by the individual Services.

If there is any question of a false positive on the color vision test (applicants do memorize these plates), just retest by turning the plates 90 degrees or sideways and change the order of flipping the cards.