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001_ro0111_Corneal Atlas_jm.indd 1 1/4/11 11:58 AM Ernest Bowling, OD, FAAO, is Center Director for VisionAmerica, a surgical co-management Table of Contents center in Gadsden, AL, and associate clinical editor of Review of & Contact Lenses. E-mail him at [email protected]. Bacterial ...... 4

Viral ...... 5

Gregg Eric Russell, OD, FAAO, is in private ...... 7 practice at the Marietta Eye Clinic in Atlanta. His clinical interests include dry eye, contact Fungal ...... 8 lenses and refractive surgery. E-mail him at [email protected]. Epithelial ...... 9

Bowman’s ...... 11

Joseph P. Shovlin, OD, FAAO, is in private Stroma ...... 11 practice in Scranton, PA, associate clinical edi- tor of Review of Optometry and clinical editor of Review of Cornea and Contact Lenses. Endothelium ...... 14 E-mail him at [email protected]. Degenerations ...... 15

Mechanical ...... 16 Christine W. Sindt, OD, FAAO, is Director of Contact Service and Associate Clinical Chemical ...... 18 Professor at the University of Iowa Hospitals and Clinics, Iowa City, IA, Chair of the AOA and Cornea Council, a monthly Inflammatory ...... 20 columnist for Review of Cornea and Contact Lenses, co-clinical editor for Review of Optometry, and photo editor for the Corneal Atlas. E-mail her at [email protected].

6 8 14 16 21

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001_ro0111_Corneal Atlas1222ac.indd 3 12/29/10 3:08 PM Bacterial

MICROBIAL KERATITIS Etiology Microbial keratitis is the most visually devastating associated with contact lens wear. While even daily wear of contact lenses carries an increased risk for infection, extended or overnight contact lens wear is the greatest risk fac- tor for infectious keratitis in patients choosing to wear contact lenses.1 Many bacteria have been identified in contact lens related microbial keratitis, with the most common organisms cultured from bacterial ulcers being Staphylococcus, Streptococcus, Pseudomonas and Moraxella.2 Culture positive enterobacter The gram-negative rod Pseudomonas Culture positive Pseudomonas corneal ulcer aeruginosa is commonly associated with microbial keratitis in soft contact lens defects in the visual axis, ulcers unrespon- wear.3 It is important to remember that sive to initial therapy, or if an unusual the organisms Neisseria gonorrhoeae, organism is suspected. Remember that Listeria, Corynebacterium and Haemophilus only approximately 40% of corneal cul- aegypticus do not require damage to the tures identify causative pathogens. For cornea and may invade directly through this reason, culturing the contact lens in intact corneal epithelium.4 addition to the corneal ulcer can aid in identifying the causative organism.5 Presentation Patients with microbial keratitis pres- Treatment ent with symptoms including decreased Ulcers need to be considered infec- vision, , moderate to severe tious until proven otherwise. Therapy ocular pain, redness, swelling and dis- begins with immediate, intensive, aggres- charge. On slit lamp examination, the sive treatment with fourth generation Pseudomonas critical finding is a focal white opacity fluoroquinolones while awaiting lab in the corneal stroma with an overlying results. Dosage is every 30 minutes for corneal epithelial defect that stains with the first six hours, followed by hourly .2 Additional findings include administration around the clock until diffuse epithelial edema, stromal infil- improvement is noted. The use of fourth tration surrounding the ulceration, and generation fluoroquinolones in the treat- mucopurulent exudation. An anterior ment of corneal ulcers is an off-label use chamber reaction and may of these medications but routinely used be present. It is important to document and no difference in efficacy with the the depth and location of the epithelial use of fourth generation fluoroquinolone defect and stromal infiltration. The ante- monotherapy when compared with com- rior chamber should be evaluated for bination therapy of fortified antibiotics cells and flare and examined for a hypo- has been noted.6 Cycloplegic drops are pyon, and the intraocular pressure should valuable for patient comfort and to pre- be checked. vent synechiae formation in accompany- Nocardia infection Much has been made regarding culture ing iritis. and sensitivity testing in cases of micro- AVOID ! Especially initially. bial keratitis. In general, consider cultures Corticosteroid treatment resulted in a statis- The patient with an infectious keratitis in ulcers greater than 1 mm to 2 mm, tically significant delay in corneal re-epithe- needs to be followed daily, with careful lialization and use did not translate monitoring of the findings. The antibi- ICD-9 Codes to a significant difference in visual acuity or otic regimen should be reduced depend- • 370.00 Corneal ulcer, unspecified infiltrate/scar size.7 Infectious keratitis may ing on the response, but should never be • 370.01 Marginal corneal ulcer worsen with topical steroid use, especially tapered below the minimum dose (usually • 370.02 Ring corneal ulcer when caused by fungus, atypical mycobac- q.i.d. to t.i.d) to prevent the possibility of • 370.03 Central corneal ulcer teria or Pseudomonas. Once the cornea has bacterial resistance. • 370.04 Hypopyon ulcer re-epithelialized and the causative organism • 370.05 Mycotic corneal ulcer has demonstrated sensitivity to the antibi- References otic (usually after 72 hours of treatment), 1. Keay L, Stapleton F, Schein O. Epidemiology of con- • 370.06 Perforated corneal ulcer a steroid may be added to the therapeutic tact-lens related inflammation and microbial keratitis: A • 371.00 /scar, 20-year perspective. Eye Cont Lens 2007;33 (6):346-353. regimen to control persistent inflammation unspecified (upon resolution) 2. Ehlers JP, Shah CP, eds. The Wills Eye Manual: Office and reduce tissue damage. and Emergency Room Diagnosis and Treatment of Eye

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001_ro0111_Corneal Atlas.indd 4 12/29/10 4:39 PM Disease, 5th ed. Philadelphia: Lippincott Williams & 5. Das S, Sheorey H, Taylor HR, et al. Association eration fluoroquinolones with the combination of fortified Wilkins, 2008:62-66. between cultures of contact lens and corneal scraping in antibiotics in the treatment of bacterial corneal ulcers. 3. Green M, Apel A, Stapleton F. Risk factors and causative contact lens related microbial keratitis. Arch Ophthalmol Cornea 2010 Jul;29(7):751-7. organisms in microbial keratitis. Cornea 2008; 27(1):22-7. 2007;125(9):1182-5. 7. Srinivasan M,Lalitha P, Mahalakshmi R,et al. 4. Reed WP, Williams RC. Bacterial adherence: First step in 6. Shah VM, Tandon R, Satpathy G, et al. Randomized Corticosteroids for Bacterial Corneal Ulcers. Br J pathogenesis of certain infections. J Chronic Dis 1978; 31:67. clinical study for comparative evaluation of fourth-gen- Ophthalmol 2009; 93(2):198-202.

Viral Infections

ADENOVIRAL is usually 5 to 12 days, and the clinical which can be used “off-label” to treat EKC. Etiology illness is present from 5 to 15 days. Most This agent has minimal toxicity when used Adenoviruses produce the most com- cases of viral resolve spon- properly and followed by saline irrigation. mon viral conjunctival infections. The taneously, without sequelae, within days In vitro, povidone iodine is effective against most common serotypes involved are 3, 8, to weeks. adenovirus as well as many other infectious 19, and 37.1 The condition is quite conta- There are four forms of adenoviral agents. Topical steroids are indicated when gious and is transmitted readily in respira- conjunctivitis: Follicular conjunc- the visual axis is involved or membrane tory and ocular secretions, eye droppers tivitis, pharyngoconjunctival fever, or pseudo-membrane formation is noted. and mascara bottles, and contaminated epidemic keratoconjunctivitis (EKC), Patients should discontinue contact lens swimming pools. The incubation period and acute hemorrhagic conjunctivitis.2 wear. Avoid the use of topical and oral anti- Follicular conjunctivitis is the mild- biotic or antiviral agents as these will not est form of adenoviral conjunctivitis. help resolution and may promote antibiotic Pharyngoconjunctival fever is the most resistance. Patients with adenoviral conjunc- common ocular adenoviral infection tivitis need to understand that the condition and is characterized by a combination of pharyngitis, fever, and conjunctivitis. Epidemic keratoconjunctivitis (EKC) is ICD-9 Codes a more severe form of conjunctivitis and • 372.00 Unspecified conjunctivitis typically lasts for seven–21days. EKC • 372.02 Acute follicular conjunctivitis can affect the cornea with coarse keratitis • 372.03 Other mucopurulent and sub-epithelial infiltrates (SEIs). SEIs conjunctivitis may last for months, affecting visual • 372.04 Pseudomembranous acuity. Acute hemorrhagic conjunctivitis conjunctivitis produces a severe, painful follicular con- • 372.11 Simple chronic conjunctivitis HSV disciform keratitis junctivitis with the development of tiny • 077.1 Epidemic keratoconjunctivitis subconjunctival hemorrhages. • 077.3 Adenoviral (acute follicular) Presentation In general, viral infections present with redness, irritation, itching, foreign body sensation, tearing and photophobia. The condition starts in one eye and then progresses to the other a few days later. Signs include conjunctival injection and swelling. The lids may be swollen. Inferior palpebral conjunctival follicles are seen. Pinpoint subconjunctival hemorrhages and membrane formation over the palpe- bral are occasionally seen. In Geographic HSV ulcer-note staining with Rose Bengal some cases multiple, focal infiltrates in Classic presentation of the cornea anterior to mid-stroma may be seen. A pre-auricular lymphadenopathy is present. A rapid, in-office immunodiag- nostic test using antigen detection is avail- able for adenovirus conjunctivitis. In a study of 186 patients with acute conjunc- tivitis, this test had a sensitivity of 88% to 89% and a specificity of 91% to 94%.3 Treatment Palliative therapy is often sufficient for most cases of adenoviral conjunctivitis: cold compresses, artificial tears and topical HZK Keratitis. Coarse keratitis shown under white decongestants/antihistamines. 5% Betadine is Old interstitial keratitis with ghost vessels and lipid light now available as an FDA-approved product deposits

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001_ro0111_Corneal Atlas.indd 5 12/29/10 4:42 PM Sclerokeratitis secondary to herpes zoster

Secondary bacterial crystalline keratopathy, after HSV keratitis showing staining with NaFl Presentation HSV keratitis, requiring PKP HZO usually begins as an influenza-like ill- hours while awake) until the corneal ulcer ness characterized by fatigue, malaise, nausea is highly contagious and should be informed heals, and then one drop three times per day and mild fever accompanied by progressive of appropriate measures to reduce the risk of for seven days.7 Topical acyclovir 3% oint- pain and skin hyperesthesia. A diffuse ery- spreading the infection to their other eye or ment (no longer commercially available but thematous or maculopapular rash appears to other people. can be obtained from specialized compound- over a single dermatome three to five days ing pharmacies) used five times a day as an later. The skin of the forehead and upper HERPES SIMPLEX KERATITIS Etiology alternative in patients with a known sensitiv- is commonly affected and strictly obeys The (HSV) is the ity to the above medications. the midline with involvement of one or more leading cause of vision loss in the United Oral antivirals are gaining use in the branches of the ophthalmic division of the tri- States. Keratitis caused by HSV is also the treatment of epithelial disease. Oral acy- geminal nerve. Involvement of the tip of the most common cause of cornea-derived clovir 400 mg five times a day is the most nose (Hutchinson’s sign) has been thought blindness in developed nations.4 The HSV common oral dosage. Alternatively, oral to be a clinical predictor of ocular involve- is a DNA virus that resides latent in the valacyclovir (Valtrex), a prodrug of acyclo- ment. Although patients with a positive trigeminal ganglion, only to resurrect during vir, can be given 500 mg three times a day. Hutchinson’s sign have twice the incidence periods of intense stress, illness, irritation Since these drugs are cleared through the of ocular involvement, one third of patients and phototoxic exposure. The disease can kidneys, it is critically important for the without the sign develop ocular manifesta- be present as superficial lesions, neurotroph- patient with renal disease that the patient’s tions.11 HZO conjunctivitis is a common ocu- ic disease, or with deep stromal involvement. nephrologist or primary care physician and/ lar finding and the conjunctiva appears swol- or pharmacist be consulted regarding dos- len and injected, with occasional vesicles and Presentation ing. For a patient on long-term oral antivi- petechial hemorrhages. Herpes zoster keratitis Patients with HSV infection present with ral therapy for recurrent disease, check cre- manifests in five basic clinical forms: rapid onset unilateral pain and redness, atinine levels to insure there is no kidney • Epithelial keratitis (acute or chronic). watering and light sensitivity. Diagnosis of damage. Normal levels of serum creatinine Multiple, fine, raised intraepithelial HSV infection is primarily based on clini- are approximately 0.8 to 1.4 milligrams lesions located paracentrally or at the lim- cal findings. The disease starts as a punctate (mg) per deciliter (dl) in adults. bus, which stain mildly with fluorescein epithelial keratitis, coalescing into the classic Finally, consider oral antiviral prophylaxis. but intensely with rose Bengal. branching epithelial ulceration with termi- Oral antiviral prophylaxis has been associated • Nummular stromal keratitis. Multiple, nal end bulbs within 24 to 48 hours.5 The with a decreased risk of recurrence of epithe- fine, granular infiltrates in the anterior dendrites stain with rose Bengal or lissamine lial keratitis, stromal keratitis, conjunctivitis, corneal stroma. green. Corneal sensitivity may be decreased. and due to HSV.8 • Disciform keratitis. A central, well-defined, The neurotrophic form of HSV disease is disc-shaped area of diffuse stromal edema characterized by areas of intense punctate without vascularization. Corneal edema with ICD-9 Codes change or epithelial denudement, and can anterior chamber inflammation. • 054.43 Herpes keratitis result in corneal scarring. Deep stromal • Limbal vascular keratitis. Limbal-vessel lesions appear as a round, fluid filled circle. ingrowth and stromal edema. May be Scarring can develop in later stages with loss HERPES ZOSTER associated with adjacent episcleral or of stromal thickness and corneal thinning. Etiology scleral inflammation. Herpes zoster ophthalmicus (HZO) is a • Neurotrophic keratitis. An inferior, oval Treatment recurrent infection of the varicella zoster epithelial defect with rolled edges. Can Treatment of active HSV keratitis consists (chickenpox) virus in the ophthalmic divi- lead to corneal perforation. of topical trifluridine 1% solution every one sion of the trigeminal dermatome, most HZO can cause either a nongranulo- to two hours until no sign of active infection often affecting the nasociliary branch. matous or granulomatous anterior (lack of dendrite patterns), then five times HZO can affect any of the ocular and with keratic precipitates and posterior syn- a day for an additional seven to 10 days.6 adnexal tissues. One in four people will echiae. The diagnosis of herpes zoster dis- Zirgan (ganciclovir) ophthalmic gel 0.15% is contract herpes zoster in their lifetime, ease is generally based on clinical findings. indicated for the treatment of acute herpetic with this risk rising markedly after 50 years keratitis. The recommended dosing regimen of age, especially in very elderly individu- Treatment for Zirgan is one drop in the affected eye als.9 Ophthalmic herpes zoster represents All patients with ophthalmic zoster, five times per day (approximately every three 10-20% of all zoster cases.10 irrespective of age or severity of symptoms,

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001_ro0111_Corneal Atlas.indd 6 12/29/10 4:42 PM should be prescribed oral antiviral drugs at keratitis, anterior stromal infiltrates, and dis- 2007; 5(3): 240-50. the first sign of disease. Patients with HZO ciform keratitis. Topical cycloplegics prevent 5. Kahn BF, Pavan-Langston D. Clinical manifestations and are treated with oral acyclovir (800 mg, five ciliary spasm associated with herpes zoster treatment modalities in herpes simplex virus of the ocular ante- rior segment. Int Ophthalmol Clin 2004;44:103-33. times daily) for seven–10 days. Early treat- inflammatory disease. Aqueous suppressants 6 Ehlers JP, Shah CP, eds. The Wills Eye Manual: Office and ment with acyclovir (within 72 hours after and topical corticosteroids should be used to Emergency Room Diagnosis and Treatment of , rash onset) reduces the percentage of eye treat associated with HZ disease. 5th Ed. Philadelphia, PA: Lippincott, Willliams and Wilkins, 2008. disorders in ophthalmic zoster patients from Consider Zostavax vaccine for your 7. Zirgan package insert. Bausch & Lomb Pharmaceuticals. 12 8. Young RC, Hodge DO, Liesegang TJ, et al. Incidence, 50% to 20-30% and also lessens acute pain. patients over 60 years of age. In the landmark recurrence, and outcomes of herpes simplex virus eye disease Famciclovir 500 mg three times daily for Shingles Prevention Study, the live attenuated in Olmsted County, Minnesota, 1976-2007: the effect of oral seven days or valacyclovir 1000 mg three vaccine reduced the risk antiviral prophylaxis. Arch Ophthalmol 2010;128(9):1178-83. times daily are alternatives to acyclovir. In of developing shingles by 51%.13 9. Johnson RW, Bouhassira D, Kassianos G, et al. The impact of herpes zoster and post-herpetic neuralgia on quality-of-life. general, the dosages for HZO are twice that BMC Med 2010;8:37. for HSV infections. Palliative therapy includ- References 10. Ragozzino MW, Melton LJ 3rd, Kurland LT, et al. ing cool compresses, mechanical cleansing of 1. Gordon, JS; Aoki, K; Kinchington, PR. Adenovirus kerato- Population-based study of herpes zoster and its sequelae. the involved skin, and topical antibiotic oint- conjunctivitis. In: Pepose JS, Holland GN, Wilhelmus KR, eds. Medicine (Baltimore) 1982;61:310-16. Ocular Infection and Immunity. St. Louis: Mosby;1996. pp. 11. Harding SP, Lipton JR, Wells JC. Natural history of her- ment without steroid are helpful in treating 877–94. pes zoster ophthalmicus: predictors of postherpetic neuralgia skin lesions. Epithelial defects associated with 2. Yanoff M, Duker JS, eds. , 3rd ed. Maryland and ocular involvement. Br J Ophthalmol 1987;71:353–58. HZO keratitis may be treated with nonpre- Heights, MO, Elsevier, 2009. 12. Cobo LM, Foulks GN, Liesegang T, et al. Oral acyclo- served artificial tears, eye ointments, punctal 3. Sambursky R, Tauber S, Schirra F, et al. The RPS vir in the treatment of acute herpes zoster ophthalmicus. adeno detector for diagnosing adenoviral conjunctivitis. Ophthalmology 1986; 93:763-70. occlusion, pressure patching, or therapeutic Ophthalmology 2006;113:1758-64. 13. Oxman MN, Levin MJ, Johnson GR, et al. A vaccine to soft contact lenses. Topical steroids are useful 4. Guess S, Stone DU, Chodosh J. Evidence-based treatment prevent herpes zoster and postherpetic neuralgia in older in the management of keratouveitis, interstitial of herpes simplex virus keratitis: a systematic review. Ocul Surf adults. N Engl J Med 2005; 352:2271-84.

Acanthamoeba Keratitis

Background tion. The life cycle of these organisms kerititis; however, it tends to form four- Acanthamoeba keratitis can be severe is comprised of two stages, trophozoite eight weeks after onset of symptoms and and vision-threatening. It was first recog- and cystic forms. Trophozoites bind to is rarely the presenting sign. Radial peri- nized in contact lens wearers in the early and desquamate the corneal epithelium. neuritis (perhaps explaining the intense 1970s, and contact lens wear is thought They secrete a variety of proteases, which pain) may be seen on slit lamp examina- to be associated with 80% of the cases.1,2 facilitate the dissolution of the corneal tion or . Unchecked, Symptom onset is greatest during the stroma.5 When environmental conditions there may be progressive corneal thinning summer months. Acanthamoeba species become unfavorable, the organism con- and risk of perforation. Up to 40% of are found in virtually every environ- verts to a dormant cystic form, which is ment. These are ubiquitous in able to survive many years. These double the soil, dust, lakes, rivers, hot tubs and walled cysts are highly resistant to killing salt water. They have been isolated from by desiccation, freeze/thaw cycles, irradia- heating, venting and air conditioner units tion, chlorination levels and antimicro- (HVAC), humidifiers, dialysis units and bial agents. contact lens paraphernalia. Acanthamoeba Co-infection with bacteria or fungi is have been found in the nose and throat common, providing food for . of healthy people as well as those with compromised immune systems. Contact Presentation lens wear and poor lens hygiene are often Acanthamoeba keratitis presents with singled out as the biggest risk factors for pain (ranging from mild foreign body acanthamoeba keratitis. The true incidence sensation to severe pain), photophobia, is not known; however, it is thought to decreased vision, injection, irritation, be rare; affecting approximately 1.65-2.01 tearing and a protracted clinical course. per million contact lens wearers per year The patient often presents with a unilat- in the United States.3 However, it has eral , where the pain is dispropor- been reported as high as 1/30000 contact tionately worse than one would surmise lens wearers per year outside the United from the clinical appearance. Early cor- States.4 neal findings include irregular epithelium, punctate epithelial erosions, microcystic Etiology edema, perilimbal injection and dendriti- There are more than 20 different form epithelial lesions. The dendritiform species, several of which are known to lesions often resemble those of herpes cause infections in humans, including A. simplex keratitis, however, the AK lesions culbertsoni, A. polyphaga, A. castellanii, A. appear edematous and necrotic rather healyi, (A. astronyxis), A. hatchetti and A. than frank ulcerations. rhysodes. A. castellanii is the most common A ring infiltrate is classically thought amoeba associated with corneal infec- of as the defining sign of acanthamoeba Early Acanthamoeba keratitis

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001_ro0111_Corneal Atlas.indd 7 12/29/10 4:42 PM patients may have mild to severe anterior lens related corneal oxygen deficiency. • Careful following of recommended uveitis. has been reported in Debridement, particularly early in the lens care systems. patients with Acanthamoeba keratitis; how- disease, will reduce the number of organisms ever, the scleral inflammation was attrib- and deprive the Acanthamoeba of its food References: 10 1. Jones DB, Visvesvara GS, Robinson NM. Acanthamoeba uted to an immune-mediated response to supply. Cationic antiseptic agents, such as polyphaga keratitis and Acenthamoeba uveitis associated with necrotic organisms and was not believed chlohexidine 0.02% and polyhexamethyl fatal meningoencephalitis. Transactions of the ophthalmologi- to be the result of active infection.6-8 biguanide 0.02%, are generally considered cal societies of the United Kingdom 1975, 95(2):221-232. Severe glaucoma has been associated primary medical treatments. Biguanides dis- 2. Illingworth CD, Cook SD, Karabatsas CH, Easty DL. Acanthamoeba keratitis: risk factors and outcome. Br J with acanthamoeba keratitis secondary to rupt the phospholipid structure of cell mem- Ophthalmol. 1995 Dec;79(12):1078-82. an inflammatory angle-closure mecha- branes. Aromatic diamides (Brolene) directly 3. Schaumberg DA, Snow KK, Dana MR. The epidemic of nism, apparently without direct infiltra- affect the nucleic acids and are Acanthamoeba keratitis: where do we stand? Cornea. 1998 tion of the organism.9 thought to have a synergistic affect with the Jan;17(1):3-10. Review. biguanides. There is a risk of significant cor- 4. Seal DV. Acanthamoeba keratitis update-incidence, molec- 11,12 ular epidemiology and new drugs for treatment. Eye. 2003 Treatment neal epithelial toxicity with q1-2h dosing. Nov;17(8):893-905. Review. Diagnosis largely depends on the abil- Corticosteroids are used to treat associated 5. Investigative Ophthalmology & Visual Science, July 2005, ity to visualize the organism. Definitive uvetitis or scleritis; however, this should be Vol. 46, No. 7. 6. Lee GA, Gray TB, Dart JK, et al. Acanthamoeba sclero- diagnosis is made by corneal scrapings. done with extreme caution because tropho- keratitis: treatment with systemic immunosuppression. Confocal microscopy is clinically useful zoite proliferation has been observed when Ophthalmology. 2002;109:1178-1182. to quickly identify the organism in vivo. exposed to steroids.13 Penetrating keratoplasty 7. Garner A. Pathogenesis of Acanthamoebic keratitis: Attempts to culture the organism is time- (PKP) may be necessary for tectonic or opti- hypothesis based on a histological analysis of 30 cases. Br J Ophthalmol. 1993;77:366-370. consuming and expensive, often with poor cal corneal rehabilitation. In most situations, 8. Lindquist TD, Fritsche TR, Grutzmacher RD. Scleral ectasia yields. Differential diagnosis includes her- PKP is postponed until resolution of infec- secondary to Acanthamoeba keratitis. Cornea. 1990;9:74-76. petic keratitis, bacterial keratitis, toxic kera- tion. There may be residual dormant cysts in 9. Kelley PS, Dossey AP, Patel D, Whitson JT, Hogan topathy (solution related), stem cell failure, the peripheral corneal, even in a cornea that RN, Cavanagh HD. Secondary glaucoma associated with advanced Acanthamoeba keratitis. Eye Contact Lens. 2006 , severe dry eye and contact appears quiet, which may incite infection Jul;32(4):178-82. after graft. After corneal transplant, protective, 10. Lindquist TD. Treatment of Acanthamoeba keratitis. maintenance doses of medication should be Cornea. 1998 Jan;17(1):11-6. used to help prevent the recurrence of the 11. Seal D. Treatment of Acanthamoeba keratitis. Expert Rev 14 Anti Infect Ther. 2003 Aug;1(2):205-8. Review. . 12. Hammersmith KM. Diagnosis and management of Acanthamoeba keratitis. Curr Opin Ophthalmol. 2006 Aug;17(4):327-31. ICD-9 Codes 13. McClellan K, Howard K, Niederkorn JY, Alizadeh H. Effect • 370.02 Ring corneal ulcer of steroids on Acanthamoeba cysts and trophozoites. Invest • 370.40-006.8 Keratoconjunctivitis Ophthalmol Vis Sci. 2001 Nov;42(12):2885-93. 14. Visvesvara GS, Stehr-Green JK. Epidemiology of free- living ameba infections. The Journal of protozoology 1990, Recommendations: 37(4):25S-33S. 15. Joslin, CE, Tu, EY, Stayner L, Davis F. The association • Avoid swimming with contact lenses on. between Acanthamoeba keratitis and showering with con- Advance keratitis with stromal involvement and • Showering in contact lenses may tact lenses. Paper presented at the American Academy of 15 hypopyon increase risk of infection. Optometry October 22, 2008.

Fungal Keratitis

Fungal keratitis is relatively rare in the 30 percent of fungal keratitis cases may be epithelium is usually raised, and at times United States (approximately 5 to 10 percent associated with bacterial co-infection. Risk may be intact, over the infiltrate. An epi- of reported cases), although it accounts for factors for the development of fungal keratitis thelial defect, anterior chamber reaction or up to 50 percent of ulcerative keratitis else- include ocular trauma, topical corticosteroids, hypopyon may be present. where in the world. Fungal keratitis is usually systemic immunosuppression, penetrating or associated with a history of ocular trauma,1 refractive surgery, chronic keratitis (vernal/ ocular surface disease,2 or topical steroid use.3 atopic keratitis and neurotrophic ulcers) and There has been a lot of attention focused on contact lens wear with certain lens solutions. the recent epidemic of fungal keratitis in soft contact lens wearers in 2005 and 2006,1,4 how- Presentation ever a recent review indicates the number of Patients present with pain, photopho- fungal keratitis cases associated with contact bia, injection, tearing and possible dis- lens wear has been steadily increasing the past charge; however, the degree of symptoms twenty years.5 may vary. In some cases, the progression of symptoms may be slow, while in oth- Etiology ers it may move very quickly. Corneal Fungi require an epithelial defect for infiltrates tend to have feathery borders, corneal penetration. Once the epithelium are generally grayish-white and may have has been violated, the present fungi can mul- satellite lesions. Larger infiltrates are asso- Acute necrotizing fungal keratitis after herpetic tiply and cause severe tissue damage. Up to ciated with poor visual prognosis. The infection

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001_ro0111_Corneal Atlas.indd 8 12/29/10 4:42 PM Diagnosis may be difficult based on clini- cal examination alone. Confocal microscopy may reveal hyphae in filamentary fungal disease such as Aspergillus or Fusarium, or budding yeast forms such as Candida.6,7 Fungal cultures are the gold standard for diagnosis.8 Corneal scrapings and cultures may be positive in up to 90 percent of initial scrapings. Most fungi grow well in blood agar or Sabouraud dextrose agar as culture media. Growth usually occurs within 3 or 4 days but can take as long as 4 to 6 weeks.9 Gram and Giemsa stains or potassium hydroxide (KOH) wet mounts are useful for identifying fungal Fungal keratitis related to contact lens wear Fungal ulcer elements. Polymerase chain reaction (PCR) is another diagnostic tool. Results from clini- cal studies suggest that PCR is more sensitive vision impairment due to corneal scarring. trum of fungal keratitis in south Florida. Ophthalmology than culture as a diagnostic aid in ocular fun- Despite maximum pharmacologic therapy, 1994; 101: 1005-1113. gal infections and is also much faster. Results early transplant during active disease may be 3. Wong TY, AuEong KG, Chan WK, et al. Fusarium kera- are known within 24 hours. However, PCR required early in cases of perforation or near titis following the use of topical anti biotic-corticosteroid 8 11 therapy in traumatized eyes. Ann Acad Med Singapore is associated with a high false-positive rate. If perforation. As many as 27% of patients 1996; 25: 862-865. there is strong suspicion of fungus and other with ocular fungal infections can require cor- 4. Khor WB, Aung T, Saw SM, et al. An outbreak of tests are negative, biopsy may be required. neal transplants.2 Fusarium keratitis associated with contact lens wear in The use of topical steroids is detrimental Singapore. JAMA. 2006;295(24):2867-73. 12 5. Tuli SS, Iyer SA, Driebe WT. Fungal keratitis and contact Treatment in the treatment of fungal keratitis. Extreme lenses: an old enemy unrecognized or a new enemy on the Topical natamycin 5% or topical ampho- caution should be used with steroids until a block? Eye Cont Lens 2007; 33 (6): 415-417. tericin B 0.15% is first-line therapy for symp- sufficient amount of time for clinical stabi- 6. Kaufman SC, Musch DC, Belin MW, et al. Confocal 8 microscopy: a report by the American Academy of toms of suspected superficial fungal keratitis. lization has been achieved because steroids Ophthalmology. Ophthalmology 2004; 111(2): 396-406. Natamycin is currently the only topical reduce the patient’s immune ability to elimi- 7. Klont RR, Eggink CA, Rijs AJ, et al. Successful treatment ophthalmic antifungal compound approved nate infection.13 of Fusarium keratitis with cornea transplantation and topi- by the FDA.10 It penetrates the cornea well cal and systemic voriconazole. Clin Infect Dis 2005; 40(12): 110-112. after topical administration and is the drug Recommendations 8. Hu WS, Fan VC, Koonapareddy C, et al. Contact lens- of choice for fungal keratitis. Amphotericin • Early on, the patient may present with related fusarium infection: case series experience in New B, because of its numerous toxicities, is no more than a “gritty” foreign body sensa- York City and review of fungal keratitis. Eye Cont Lens administered as a second-line treatment to tion with only a small, indistinct infiltrate. 2007; 33 (6): 322-328. 9. Thomas PA. Current perspectives on ophthalmic myco- natamycin. Recommended dosage is 1 mg/ • Fungal keratitis is commonly confused ses. Clin Microbiol Rev 2003; 16: 730-797. kg/day intravenously or topically in 0.15% to with bacterial keratitis. There should be a 10. O’Brien TP. Therapy of ocular fungal infections. 0.3% solution every 30 to 60 minutes. Side high level of suspicion of fungal agents if the Ophthalmol Clin North Am 1999; 12: 33-50. effects can include renal toxicity, headaches, lesions do not resolve/ improve despite anti- 11. Winchester K, Mathers WD, Sutphin JE. Diagnosis 10 of Aspergillus keratitis in vivo with confocal microscopy. fevers, chills and anorexia. As is the case for biotic therapy. Cornea 1997; 16(1): 27-31. most anterior segment injuries and infections, • Steroids will worsen/exacerbate the 12. O’Day DM, Ray WA, Robinson RD. Efficacy of anti- cycloplegics should be dispensed to improve disease and should not be used in suspected fungal agents in the cornea. II. Influence of corticosteroids. patient comfort. In addition to standard ther- fungal infections. Invest Ophthalmol Vis Sci 1984; 25: 331-335. 13. Krachmer JH, Mannis MJ, Holland EJ. Cornea, apy for fungal keratitis, Voriconazole (topical • Optimal contact lens care. Nearly all 2nd Edition, Vol. 1. Philadelphia: Elsevier Mosby, 2005. and oral) has also been successfully used to of the cases of contact lens-related fungal pp.1101-1113. impart a clinical cure. keratitis reported from a University of Florida 14. Iyer SA, Tuli SS, Wagoner RC. Fungal keratitis: Mechanical debridement of the corneal study showed poor contact lens care.14 Emerging trends and treatment outcomes. Eye Cont Lens epithelium may aid in penetration of topical 2006; 32: 267-271. References: medication into the stroma while provid- ICD-9 Codes ing a specimen for histopathological stains 1. Chang DC, Grant GB, O’Donnell K, et al. Multistate out- break of Fusarium keratitis associated with use of a contact • 370.05 Mycotic corneal ulcer and evaluation. Therapeutic penetrating lens solution. JAMA 2006; 296(8): 953-63. • 370.04 Hypopyon corneal ulcer keratoplasty is often required to restore 2. Rosa RH Jr, Miller D, Alfonso EC. The changing spec-

Epithelial

The corneal epithelium serves a variety of many of the same properties of regeneration together through a variety of tight adher- roles, including serving as the primary mode after injury and, fortunately enough, recovers ences. The typical epithelial layer is approxi- of protection for the corneal surface and as in rapid fashion. For purposes of brevity, the mately 50 microns thick. During cell division, the interface tissue between the corneal stro- corneal epithelium consists of deep columnar the epithelial cells migrate and flow more ma and the tear film. Derived from surface cells attached to the anterior limiting lamina anteriorly towards the surface, ultimately los- ectoderm, it can be best described as a nonke- (or Bowman’s membrane), midlayer polygo- ing their nuclei and becoming “wafer” thin. ratinized stratified squamous layer posessing nal cells, and surface wing cells all bound Corneal abrasions are one of the most

REVIEW OF OPTOMETRY January 2011 9

001_ro0111_Corneal Atlas.indd 9 12/29/10 4:43 PM common forms of ocular trauma present- in the visual axis, consider a targeted epi- ing to an optometric clinic. Damage to the thelial debridement, particularly if located corneal epithelium and its subsequent repair near the patients’ visual axis. is influenced by a variety of factors, includ- • For patients with EBMD, Meesman’s, ing the presence of physical conditions such and Reis–Buckler’s, consider the use of as diabetes, Sjögren’s or other tear chemistry bandage soft lenses for episodes of recur- altering illness, corneal denervation, lagoph- rent erosion. Furthermore, encourage the thalmus, recurrent corneal erosions, and use of nightly hyperosmostic ointments to basement membrane degenerations or dys- limit intermittent nightly erosions. trophies. Most epithelial trauma will recover within three to five days as the epithelial cells Treatment-Trauma slide over to cover adjacent damage. Large or Epithelial microcysts of Cogan’s The treatment will depend upon the total abrasions can take significantly longer extent and presentation of the injury. In to heal. Careful attention needs to be paid to cases where there are irregular, ragged the size, position, and depth of the abrasion Subepithelial mucinous corneal dys- edges of epithelial tissue, it is essential to and whether or not any signs of infiltrate are trophy is a very rare autosomal dominant debride that tissue. Antibiotic drops can present. Fluorescein dye should be instilled condition characterized by frequent recur- be dosed from qid to q1h depending on to measure the abrasion and monitor its rent erosions in the first decade of life the size and depth of the injury, along improvement; for deeper abrasion it’s imper- followed by progressive vision loss. The with a cycloplegic agent bid-qid for pho- ative to assess for risk of perforation and lesions involved the entire cornea, but are tophobia. A bandage contact lens can be check for Seidel’s sign. Should either of these typically found centrally.2 extremely beneficial to promote reepithe- be detected, prompt medical comanagement Meesman’s is a bilat- lialization and improve patient comfort. should be initiated. Though any abrasion can eral autosomal dominant disorder that predispose to future erosions, those caused by generally appears early in life as epithelial ICD-9 Codes paper, fingernails or tree branches are more microcysts in the first decade of life. • 918.00 Corneal Abrasion commonly associated with recurrent erosions Patients may remain asymptomatic for and the patient should be treated and educat- years, until epithelial erosions associated • 367.22 Irregular ed accordingly. Sodium chloride eyedrops and with rupture of the microcysts produce • 371.42 Recurrent erosion of cornea ointments, such as Muro 128 5%, are advised. symptoms, such as impaired visual acuity, • 371.51 Meesman’s There are a variety of corneal epithelial pain and photophobia.3 • 371.52 EBMD dystrophies. Almost all are considered Lisch epithelial dystrophy (LECD) recessive in nature and can cause the is a relatively new corneal disorder that Treatment-Dystrophies and patient symptomatic visual distortion was first described in 1992.4 It is unusual Degenerations in the form of irregular astigmatism or because it is linked to the X chromosome. EBMD treatment depends on the level intermittent pain secondary to recurrent It is a gelatinous, whorl-like corneal dys- of visual performance and patient discom- erosions. trophy associated with surface deposition fort. For mild presentations, the patient Epithelial basement membrane dys- and appears as epithelial microcysts on can use artificial tears and hyperosmotic trophy (EBMD), also known as anterior retroillumination. It typically begins in drops and/or ointments. Ointment at basement membrane or Cogan’s dystro- childhood, sparing the center of the cor- bedtime is especially helpful for those phy, is described as hereditary in nature, nea. As the opacities progress toward the patients having difficulty with overnight bilaterally presenting, and progressive.1 center they can decrease acuity but are erosions. For patients with blurred vision Typically, EBMD can be visualized using not associated with recurrent erosions.5 due to irregular astigmatism, a soft, rigid vital dyes such as fluorescein and a wrat- Gelatinous drop-like corneal dystrophy or hybrid contact lens can be utilized. ten filter and looking for areas of discrete is a rare corneal presentation associated If these treatments are unsuccessful, the negative staining, as well as irregularity on with surface deposition thought to be faulty epithelium can be debrided by dia- the corneal topography. Typically these caused by a mutation of the M1S1 gene.6 mond burr keratectomy, phototherapeutic patients will have reduced acuity which Typically associated with Japanese back- keratectomy (PTK), or anterior stromal can be improved with a rigid gas perme- ground, the condition has been noted in micropuncture (ASM). Treatment of the able trial lens. other parts of the world and characterized other epithelial dystrophies need to be by severe . considered on a case-by-case basis where treatment ranges from symptomatic relief Pearls with lubrication, Muro 128, and bandage • Never use a bandage contact lens with contact lenses to more advanced treat- corneal trauma that might be at risk for ments including debridement, PTK, and fungal infection. For instance, caution penetrating and lamellar keratoplasty. should be used with a patient presenting However, there is a risk of the dystrophy to the office with a tree branch injury to recurring within the graft. All tests should the cornea. be medically necessary and be important • Consider using a stiffer modulus soft for the management of the case. contact lens for corneal irregularities in All tests should have some type of the corneal visual axis. Stiffer designs can interpretation of findings. drape over irregular zones and dampen • Corneal topography—useful for cases of the effects of irregular astigmatism. epithelial irregularity involving visual axis. • For patients considering sur- • Anterior segment photography–useful Epithelial basement membrane dystrophy gery AND possessing significant EBMD for documenting presence and extent of

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001_ro0111_Corneal Atlas.indd 10 12/29/10 4:43 PM sur- face changes. Tear film performance Subepithelial mucinous corneal dystrophy. Clinical and path- 5. Aldave A, Sonmez B. Elucidating the molecular ological correlations. Arch Ophthalmol 1993; 111: 1106-14. genetic basis of the corneal dystrophies. Arch Ophthalmol tests – Shirmer’s I or II, tear break up 3. Jalbert I, Stapleton F. Management of symptomatic 2007;12592):172-186. time, and phenol red test. Meesmann dystrophy. Optom Vis Sci. 2009; 86: E1202- 06. 6. Ha NT, Fujiki K, Hotta Y, Nakayasu K, Kanai A. Q118X 4. Lisch W, Steuhl KP, Lisch C, Weidle EG, Emming CT, mutation of M1S1 gene caused gelatinous drop-like corneal References: Cohen KL, Perry HD. A new, band-shaped and whorled dystrophy: the P501T of BIGH3 gene found in a family with 1. http://emedicine.medscape.com/article/1193945-overview. microcystic dystrophy of the corneal epithelium. Am J gelatinous drop-like corneal dystrophy. Am J Ophthalmol 2. Feder RS, Jay M, Yue By, Stock EL, O’Grady RB, Roth SI. Ophthalmol. 1992; 114: 35-44. 2000; 130: 119-20.

Bowman’s

REIS-BUCKLERS (CORNEAL DYSTROPHY Recommendations OF BOWMAN LAYER TYPE 1) This condition must be differentiated Gray, hazy, reticular deposits (crystal- from several anterior stromal condi- lization) typify this Bowman’s layer dys- tions. To add to the confusion anterior trophy.1-3 The deposits will generally form membrane dystrophy of Grayson and symmetrical patterns in each eye and can Wilbrandt and the honeycomb dystrophy easily be detected at the slit lamp. The of Thiel and Behnke may represent clini- opacities cause an elevation of the surface cal variants of Reis-Bucklers dystrophy..2 epithelium and often create a visual dis- Management of the epithelial erosion turbance by affecting surface epiuthelium poses the major problem earlier in life. as well as underlying stromal areas of the When opacification of the cornea cornea.1 It is believed to be an autosomal impairs vision significantly, superfi- dominant inherited corneal dystrophy cial keratectomy may improve vision. associated with mutations in the TGFBI Advanced cases require lamellar or full gene and in some cases with R124L and thickness grafting but recurrence is com- G623D mutations.1,3 Onset generally mon. Over the past decade, researchers occurs by the first decade of life. This using molecular genetics have redefined dystrophy is quite rare and it’s incidence dystrophies of Bowman’s layer to include is unknown.1 two distinct entities, or Reis-Bucklers and Patient history and symptoms will Thiel-Behnke.1 invariably include recurrent corneal ero- sion (traumatic or spontaneous), pain, light sensitivity and visual disturbance/ ICD-9 Codes distortion. The episodes of recurrent • 371.52 other anterior corneal dystro- erosion tend to occur multiples times phy 2 Reis-Bucklers each year. A severe disruption of the • 371.42 recurrent corneal erosion basal epithelial cells and their stromal • 371.0 corneal scar and opacity code attachments accounts for the frequent Treatment and management includes range erosions. The epithelium is loosely topical palliative therapy to reduce the attached since a basement membrane is frequency of recurrent corneal erosion 2 References focally absent. After age 30, the erosions that includes artificial tears, epithelial 1. Bushley DM, Afshari NA:Reis-Bucklers Corneal tend to become infrequent, but acuity debridement (manual or laser) for the Dystrophy. IN:Roy FH, Fraunfelder FW and Fraunfelder FT: continues to decline due to increased recurrent erosions, and keratectomy or Current Ocular Therapy. Saunders/Elsevier, New York, 2008, superficial corneal opacification.3 Early keratoplasty (lamellar or penetrating) for pp. 391-2. 2 2. http://dro.hs.columbia.edu/reisbucklers.htm (Digital reticular superficial opacity will advance visual restoration. Recurrence of this Reference of Ophthalmology Corneal & External Diseases, to a honeycomb, fishnet pattern of the anterior corneal dystrophy is not uncom- 2003). central and mid-peripheral cornea with mon. Over-the-counter pain-relievers, 3. Laibson PR: Anterior Corneal Dystrophies and Corneal prominent corneal nerves. An increased lubricants, NSAIDs and cycloplegics can Erosions. IN: Leibowitz HM: Corneal Disorders: Clinical corneal thickness, irregular astigmatism be used for pain management when nec- Diagnosis and Management. WB Saunders Co, New York, 4 1984, pp 222-4. and decreased corneal sensation are hall- essary. There are no systemic treatments 4. http://legacy.revoptom.com/index.asp?page=2_13021. marks of the corneal malady.1,2,4 for this dystrophy. htm (Review of Optometry On-line).

Stroma

The stroma makes up the bulk of the allow for the transparency of the cornea, corneal dystrophies, including granu- corneal structure and is composed mainly as well as provide mechanical strength. lar, lattice, Avellino, and Reis-Bückler, of water, collagen and keratocytes. It is Descemet’s membrane is a thick base- have been linked to a mutation in the the specific arrangement of the tightly ment membrane that is located at the Transforming Growth Factor Beta 1 gene bound collagen fibers in the stroma that posterior portion of the stroma. Four (TGF-1), also known as the BIGH3 gene.1

REVIEW OF OPTOMETRY January 2011 11

001_ro0111_Corneal Atlas.indd 11 12/29/10 5:21 PM Corneal Fleck Dystrophy (CFD) is a rare autosomal dominant dystrophy with that is often asymptomatic. Photophobia, reduced vision and recurrent erosions may occur. It is character- ized by bilat- eral irregular shaped “flecks” of greyish matter in the posterior stroma.6 Posterior amorphous corneal dystrophy is a rare condition characterized by bilateral sheet- like opacification of the posterior stroma in association with corneal flattening and thinning It appears to be nonprogressive and patients are asymptomatic.7 Treatment Granular corneal dystrophy Retro illumination of advanced Fuch’s dystrophy The treatment for the stromal corneal dystrophies would be observation and Types of Stromal Dystrophies cial scarring patterns that are often greatest lubrication for corneal erosions if they Lattice corneal dystrophy (LCD) is the in the central cornea. The patient may occur. Phototherapeutic keratectomy most common of the stromal dystrophies. experience corneal erosions, photophobia (PTK) and corneal transplants are options It has an autosomal dominant pattern and irritation that can occur in early child- as vision becomes impaired, but the dys- of inheritance and appears after the first hood. Analysis of the area with confocal trophy can recur in the graft. decade of life as a linear branching pat- microscopy will often reveal the absence tern that affects the central cornea and of Bowman’s layer. Vision can vary and is Pearls can increase over time. LCD is associated diminished by the severity of superficial Monitor visual acuity with contrast with a genetic mutation in the BIGH3 scarring and irregular astigmatism. changes. While Snellen acuity might be gene, resulting in deposits of amyloid Macular corneal dystrophy (MCD) is good, loss of contrast will affect visual within the anterior corneal stroma. Five the least common, but most severe, of quality more and result in patient com- subtypes of LCD have been identified. the stromal corneal dystrophies. Three plaints of performance. LCD Type I is the classic form of LCD. subtypes of MCD have been described Symptoms include decreased vision and based on the presence or absence of Tests to help delineate structure and recurrent corneal erosions. immunoreactive keratan sulfate within function Granular corneal dystrophy (GCD) various tissues. Type I does not have Corneal topography—useful for cases is a bilateral, autosomal dominant dis- immunoreactive keratan sulfate in the of stromal thinning causing irregularity ease associated with a mutation in the corneal stroma, keratocytes, sera or carti- involv- ing the corneal surface. BIGH3 gene that leads to the deposi- lage, and is the most common variant of Anterior segment photography—useful for tion of a hyaline material in the corneal MCD worldwide. It is an inherited auto- documenting presence and extent of stro- stroma. It typically presents within the somal recessive condition. It is typically mal changes. first decade of life with focal granular noted during the first decade of life, char- Pachymetry—useful for documenting deposits between the anterior to mid acterized by gray-white anterior stromal thickness changes or variations. stromal regions. These opacities are dis- lesions similar to GCD. There is severe crete deposits located centrally, with clear stromal haze throughout the entire stro- cornea located in the periphery and clear ma and limbus to limbus, with patients ICD-9 Codes cornea between deposits. The disease is typically developing severe visual loss by • 371.53 Granular corneal dystrophy typically asymptomatic early on, but with the second to third decade of life. • 371.54 Lattice corneal dystrophy time the opacities can coalesce and lead Schnyder corneal crystalline dystrophy • 371.55 Macular corneal dystrophy to decreased vision. Recurrent corneal (SCCD) is a slowly progressive autosomal • 371.56 Crystalline corneal dystrophy erosions can occur in GCD but at a lower dominant dystrophy that appears early in incidence than in LCD. Three types of life, but may not cause vision loss until GCD have been described. GCD Type the fifth decade of life. It is linked to a References 2 1. www.webeye.ophth.uiowa.edu. Birkholz ES, Syed NA, I is the classic form of GCD. Avellino metabolic defect of corneal keratocytes Wagoner MD. Corneal stromal dystrophies: A clinico- corneal dystrophy is GCD Type II. It is that leads to crystalline lipid deposition. pathologic review. linked to a mutation in the BIGH3 gene Clinically the disease presents with a 2. Keefe KS, Milman T, Rodrigues MM, Hidayat AA. that leads to a deposition of both hya- ring-shaped accumulation of fine needle- Conjunctival and Corneal Pathology. Albert and 3. Jakobiec’s Principles and Practice of Ophthalmology, 3rd line and amyloid in the corneal stroma. shaped polychromatic crystal deposits edition. Saunders. 2008: 3592-95. Typically, patients present in their second within Bowman’s layer and the anterior 4. Poulaki V, Colby K. Genetics of anterior and stromal decade with granular opacities like in stroma, and is often associated with a pre- corneal dystrophies. Seminars in Ophthalmology, 2008; GCD, but later in the disease process senile peripheral lipid arcus.1 23: 1,9-17. 5. Bron AJ. Genetics of the Corneal Dystrophies: What develop lattice lines as well. The disease Congenital stromal dystrophy is an we have learned in the past 25 years. Cornea 2000; was thought to have originated from a autosomal dominantly inherited con- 19(5): 699-711. family in Avellino, Italy. However, GCD dition that is caused by mutations in 6. http://www.ncbi.nlm.nih.gov/bookshelf www.dro. type II has now been reported in patients the DCN (decorin) gene, leading to hs.columbia.edu/fleck. 3,4 7. Moshegov CN, Hoe WK, Wiffen SJ, Daya SM. from many other countries as well. corneal haze and reduced visual acuity. Posterior amorphous corneal dystrophy. A new pedi- Reis Buckler is GCD Type III. It is is common, and corneal thick- gree with phe- notypic variation. Ophthalmology. 1996 char-acterized by faint, gray-white superfi- ness is increased.5 Mar;103(3):474-8.

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001_ro0111_Corneal Atlas.indd 12 12/29/10 5:08 PM Endothelium

The endothelium is the posterior layer and form bullae, which can rupture, caus- at birth. Type II (CHED II) is of the cornea, consisting of a single layer ing foreign body sensation and pain, as more common but more severe. It is of cells, about 5µm thick, bound together well as exposing the cornea to the danger inherited as an autosomal-recessive trait, and predominantly hexagonal in shape. of infectious keratitis. associated with and corneal Anteriorly it is in contact with Descemets Posterior polymorphous corneal dys- edema from birth. membrane and posteriorly with the aque- trophy (PPCD) is an autosomal dominant X-linked endothelial corneal dystro- ous humor. It is the structure respon- disorder with extremely variable expres- phy (XCED) was first described in 2006. sible for the relative dehydration of the sion. Three genes have been implicated in The course in XECD is slowly progres- corneal stroma. In the normal adult eye PPCD (VSX1, COL8A2, TCF8), but the sive with intermittent corneal clouding the cell density varies from around 3000 evidence implicating VSX1 and COL8A2 in the form of ground glass and moon cells/mm2 in the central cornea to about is questionable. PPD presents earlier than crater-like changes of the corneal endo- 2000 cells/mm2 in the periphery. With Fuchs’ and is typically more benign. It thelium. The corneal opacification may age, disease or trauma, the cell density is characterized by the early appearance be severe and associated with nystagmus. decreases but with disease or trauma this of vesicle-like lesions, bands or diffuse In advanced cases, a subepithelial band reduction may affect corneal transparen- opacities. These opacities represent more keratopathy develops.6 cy, as some fluid then leaks into the cor- diffuse thickenings in Descemet’s mem- nea.1 The endothelial corneal dystrophies, brane. PPD can result in peripheral ante- Treatment which result from primary endothelial rior synechiae so these patients must be Early treatment includes hypertonic dysfunction, include Fuchs’ endothelial monitored for increased intraocular pres- solutions during the day and nighttime corneal dystrophy (FECD), posterior sure. Corneal edema is also a feature of hypertonic ointment. With extreme polymorphous corneal dystrophy (PPCD) PPD.4 Congenital hereditary endothelial epithelial edema, bullae may form and and congenital hereditary endothelial dys- dystrophy (CHED) presents at or shortly cause pain and photophobia. Bandage trophy (CHED). after birth with bilateral corneal edema. Fuch’s dystrophy (FECD) is an auto- The pathology of CHED is attributed somal dominant inherited disease that to endothelial cell degeneration during affects women greater than men. It typi- gestation.5 There are two types: Type I cally presents in the 5th-6th decade of (CHED 1) is inherited as an autosomal- life as multiple central corneal guttata dominant trait that presents with clear (excresences of Descemet’s membrane) associated with pigment dusting on the endothelium. The condition spreads from the center toward the periphery. As the endothelial cells fall, the remain- ing cells enlarge to cover the gap. With the reduced number of endothelial cells, the pump function suffers.2 This leads to corneal edema and loss of visual acuity. Vision is typically worse upon awakening because of the swelling induced by night- time lid closure.3 In more advanced stag- es, the epithelial microcysts later coalesce Fuch’s dystrophy in retro illumination

Corneal cross section of Fuch’s dystrophy with Fuch’s dystrophy with edema notable guttae Retro illumination of Fuch’s dystrophy

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001_ro0111_Corneal Atlas.indd 14 12/29/10 5:22 PM the results have been impressive with Endothelial cell photos graft survival rates.7 Pachymetry—useful for documenting Because of the complications associ- thickness changes or variations in cornea. ated with the surgery, including healing time, graft failure, and visual variability, the surgery has largely been relegated to ICD-9 Codes second choice behind DSEK. • 371.57 Corneal guttata / Fuch’s Descemet’s stripping endothelial ker- dystrophy ato- plasty (DSEK) is a surgery designed • 371.58 Posterior polymorphous to replace the endothelium alone without dystrophy violating any of the overlying structures, including stroma and epithelium. The 1. http://medical- dictionary.thefreedictionary.com/ surgery has an even higher rate of success corneal+endothelium http://emedicine.medscape.com/ compared to PK as long as graft adhesion article/1193591- overview. to the recipient cornea is successful.8 2. DeNaeyer G. Diagnosing and Treating Corneal Newer techniques of reducing graft Dystrophy, Contact Lens Spectrum, June 2008. 3. Bass S. The genetics of corneal dystrophies. Rev dislocation have made the surgery even Optom;143(11);2006. safer. Graft rejection can be difficult to 4. Maumenee AE. Congenital hereditary corneal dystro- spot, so it is pru- dent to look for keratic phy. Am J Ophthalmol 1960; 50:1114-24. precipitates or diffuse corneal edema.9 5. Schmid E, Lisch W, Philipp W, Lechner S, Göttinger W, Schlötzer-Schrehardt U, Müller T, Utermann G, Janecke Large guttae from Fuch’s dystrophy shown on AR. A new, X-linked endothelial corneal dystrophy. Am J Pearls Ophthalmol. 2006 Mar;141(3):478-87. specular microscopy Caution should be given for use of 6. Thompson RW, Price MO, Bowers PJ, Price FW. mitomycin C for procedures in Fuchs’ Long-term graft survival after penetrating keratoplasty. Ophthalmology. 2003; 110: 1396-402. soft contact lenses may provide tem- patients as studies have raised the poten- 7. Terry MA, Hoar KL, Wall J, Ousley P. Histology of porary relief. However, these patients tial for further damage. Monitor corneal dislo- cations in endothelial keratoplasty (DSEK and require careful follow-up care to reduce grafts with pachymetry to look for signs DLEK): a laboratory-based, surgical solution to disloca- the risk of stromal neovascularization of rejection. Typically, the graft will tion in 100 consecutive DSEK cases. Cornea. 2006; 25: 926-32. or infectious keratitis. If at some point thicken over time. 8. Jordan CS, Price MO, Trespalacios R, Price FW Jr. vision degrades to a disabling level, sur- Graft rejection episodes after Descemet stripping with gery should be considered. Tests to help delineate structure and endothe- lial keratoplasty: part one: clinical signs and Penetrating keratoplasty had been the function symptoms. Br J Ophthalmol. 2009; 93: 387-90. Epub 2008 Nov 19. gold standard for treatment of complica- Anterior segment photography—useful for 9. Roh DS, Funderburgh JL. Impact on the corneal endo- tions relating to Fuchs’ dystrophy and documenting presence and extent of stro- thelium of mitomycin C during photorefractive keratec- other endothelial disorders. Long term, mal thickening or other disease changes. tomy. J Refract Surg. 2009; 25: 894-7.

Degenerations

Keratoconus and pellucid marginal the apex of the cone that disappear with digi- in , which can then leave scarring. degeneration are the two most common tal pressure. Breaks in Bowman’s membrane Topography reveals vertical flattening with noninflammatory corneal ectasias. Though can lead to scarring and subepithelial fibrosis. horizontal steepening centrally, while inferior- they have very distinct features, early cases Acute ruptures in Descemet’s membrane can ly there is vertical steepening with horizontal of either can be difficult to distinguish lead to swelling or hydrops. Corneal topogra- flattening. This results in the classic bowed or from the other.1 phy reveals inferior steepening with paracen- “bent bowtie” appearance on topography. Keratoconus is seen in adolescents and tral thinning and elevation of the posterior Acute Hydrops is caused by a break in young adults. Its onset is usually at puberty. and anterior corneal surfaces.2 Descemet’s membrane with subsequent influx There may be a family history in 10% of The onset of pellucid marginal degenera- of aqueous into the stroma. The break is patients. It may be associated with atopic tion is usually similar to keratoconus, in the self-repairing, with resolution over weeks to disease, Down syndrome, pigmen- second through fourth decades of life.3 It is months. Hyperosmotics may hasten recovery tosa, Leber’s congenital amaurosis, Marfan also bilateral, but in contrast to keratoconus, and rarely does the cornea thin enough to syndrome, Ehlers-Danlos, osteogenesis imper- it is not inherited and does not have other perforate. A penetrating keratoplasty (PKP) fecta, or other noninflammatory connective typical ocular or systemic associations. The may be indicated if central scarring is severe, tissue diseases.1 Patients present with blurred corneal ectasia is located peripherally, usually although, frequently CL fitting is easier after a vision and exhibit progressive with in the inferior cornea extending from 4 to 8 hydrops episode. PKP is contraindicated dur- irregular astigmatism. Slit lamp examination o’clock positions. The thinning is typically ing the acute phase of the disease. reveals central or paracentral corneal thinning 1 to 2 mm wide, and located 1mm to 2 mm In contrast to keratoconus and pellucid with protrusion of the cornea at the area of from the limbus. Maximal corneal protrusion marginal degeneration, Terrien’s marginal thinning. Usually the apex of protrusion is occurs just superior to the area of thinning, in degeneration usually occurs in middle age just below the center of the cornea. The base contrast to keratoconus. The name “pellucid” to elderly males. The thinning usually starts of the cone is often outlined by a Fleisher means “clear.” The cornea is clear without superiorly and may occasionally be accom- ring, or an epithelial iron line. Vogt’s striae any iron rings or striae. Typically there is no panied by inflammation. Neovascular are stress lines in Descemet’s membrane at scarring; however, acute hydrops can occur as vessels may cross the area of thinning and

REVIEW OF OPTOMETRY January 2011 15

001_ro0111_Corneal Atlas.indd 15 12/29/10 5:22 PM ICD-9 Codes • 371.60 keratoconus unspecified • 371.61 keratoconus stable • 371.62 keratoconus acute hydrops • 371.00 corneal scar unspecified • 367.22 irregular astigmatism • 371.48 Terriens marginal degeneration • 371.10 Iron deposits cornea

topography is not keratoconus and diagnosis should not be made solely on an axial topo- Keratoconus with apical thinning, central scarring, Noticable corneal bowing in keratoconus graphical map. Comprehensive diagnosis, vogts striae and Fleischers ring treatment, topography interpretation and fit- ting videos are available at www.GPLI.org. lamellar keratoplasty, and contact lenses. Refrences there may be corneal lipid deposition. 1. Cornea, second edition volume 1, Krachmer, Mannis and Pearls Holland editors, Elsevier 2005 pages 955-74. Treatment Keratoconus should be considered any- 2. J Refract Surg. 2009 Oct;25(10 Suppl):S958-62. Treatment options for Keratoconus include time visual acuity does not meet expected Keratoconus detection using corneal topography. Holladay JT. 3. Joseph A, Fernandez ST, Ittyarath TP, Williams J. collage crosslinking, INTACTS, full thick- norms and other pathology is not obvious. Keratectomy in terriens marginal degeneration. Indian J ness penetrating keratoplasty or deep anterior All inferior steepening seen on corneal Ophthalmol 1984;32:113-4.

Mechanical

ABRASION Presentation rospasm and tearing. The time, place and Corneal abrasions are a common form Slit-lamp biomicroscopy of the injured activity surrounding the injury should be of injury resulting from ocular trauma. cornea reveals epithelial disruption and dif- noted. For medical and legal purposes, the When the cornea is injured or damaged, fuse corneal edema. In severe cases, when visual acuity (VA) should be taken before sight-threatening consequences are always edema is excessive, folds in Descemet’s performing any procedures. Differentials a possibility especially in the contact-lens membrane may be visible. The corneal include recurrent corneal erosion, herpes wearing patient. Contact lenses can com- abrasion should be documented for loca- simplex keratitis, and confluent superficial promise the corneal epithelium and may tion, size, shape and depth with either a punctate keratopathy.2 facilitate the development of infectious or drawing or photograph, making any nota- non-infectious keratitis. It is important to tion of infiltrative process. This visual Treatment recognize the signs and symptoms of cor- documentation will aid in follow-up to There are several treatment options neal abrasion in order to ease the patient’s chart the healing progress. Fluorescein for corneal abrasions, including bandage pain and provide proper medical manage- dye can be instilled to identify the corneal soft contact lenses, topical antibiotic oint- ment to hasten visual recovery. defect. The newly created wound appears ment and drops, topical non-steroidal bright green compared to the rest of the and steroidal anti-inflammatory drops, Etiology cornea because the dye accumulates in the cycloplegic preparations and hypertonic Damage to the corneal epithelium results defect.1,2 The anterior chamber should be drops and ointments. Topical antibiotics in loss of the connections of the surrounding observed and any anterior chamber reac- are the mainstay of corneal abrasion ther- epithelial cells, but Bowman’s layer generally tion should be noted. apy. There is a risk of infection with any remains intact. Deeper involvement affecting Patient symptoms include eye pain, for- open wound or defect involving the basil stroma is rare and generally due to traumas eign-body sensation, photophobia, blepha- lamina. Topical antibiotics such as poly- from a sharp or abrasive object. Often, cor- myxin B/trimethoprim, aminoglycosides neal flaps of various sizes and thickness can or fluoroquinolones are all reasonable for be seen.1 The speed by which the abrasion providing prophylactic antibiotic cover- resolves can be affected by a variety of factors age.3 Depending on the extent and sever- including whether the patient has diabetes, ity of presentation, dosing might be more corneal denervation, dry eye, lagophthalmus, aggressive at q2h for 24 hours or more previous recurrent corneal erosions or base- conservative at q.i.d. Antibiotic ointments ment membrane changes. In general, an epi- can be liberally applied during the day thelial insult will recover within 24-48 hours or augment drops by using them at bed- and is accomplished by having the neighbor- time.2 Ointments tend to provide better ing epithelial cells slide over and begin cover- barrier and lubricating function, but will ing the wound. Common causes of mechani- temporarily blur vision. Debridement of cal abrasions are fingernail, paper, foreign loose or hanging epithelium is necessary body, curling iron, mascara brush, plant or to enhance healing.1,2 Therapeutic soft other vegetative source and contact lens.1 Corneal abrasion from finger nail contact lenses can be used in abrasion

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001_ro0111_Corneal Atlas.indd 16 12/29/10 5:09 PM management. Large abrasions have been sign of infection. Lesions such as these Cullom RD, Chang B eds. The Wills Eye Manual: Office and Emergency Room Diagnosis and Treatment of Eye Disease. found to heal more quickly under the should be considered vision-threatening Philadelphia, PA: JB Lippincott, 1994: 22-3. 3-5 protection of a bandage contact lens. and may warrant culturing and the use of 3. Gurwood AG. Managing corneal abrasions. www.optom- The use of bandage contact lenses, how- fortified antibiotic therapy.2 To prevent etry.co.uk. ever, does not come without risk, includ- recurrent erosion and reduce corneal 4. Webster RG. Corneal Injuries. In: Smollen G, Thoft RA. The Cornea. Boston: Little, Brown & Co. 1987: 517-27. ing ocular irritation, epithelial and stro- edema, a hypertonic solution or oint- 5. Fujikawa LS, Nusenblatt RB. Recurrent and chronic mal edema, sterile infiltrates and hypo- ment may be prescribed along with the corneal epithelial defects. In: Abbott RL, ed. Surgical pyon, microbial infection and ulceration.4 other medications after the cornea has Intervention in Corneal and External Diseases. New York, Bandage contact lenses should be avoided re-epithelialized.2 NY: Grune & Stratton. 1987: 59-67. 6. Sowka J, Gurwood A, Kabat A. Handbook of Ocular in ALL situations where plant injury or Disease Management. Rev Optom. false fingernails is suspected because of Recommendations the risk of fungal keratitis.5 If the patient’s blepharospasm is Bed rest, inactivity and over-the- intense and visual acuity cannot be ICD-9 Codes counter analgesics can be used to manage obtained, instill one drop of anesthetic • 364.01 Iritis, acute pain.6 Topical non-steroidal anti-inflam- onto the bulbar conjunctiva. This should • 918.1 Corneal abrasion matory drops can be a useful adjunctive allow you to immediately record visual • 918.2 Conjunctival abrasion therapy for the management of pain from acuity. A new (sterile) bottle of anesthetic • 930.1 Corneal foreign body. corneal abrasion and often obviate the should be used if a penetrating injury is need for oral pain medications. These suspected. medications provide patient comfort and Always remember to evert the upper do not adversely affect corneal healing lid to check for residual foreign substance. Exposure staining of the ocular surface time.6 Oral analgesics may be necessary Cylcoplegics will make the patient more appears to be associated with incomplete for pain not controlled by topical medi- comfortable and decrease the likelihood blinking and can have several different cations. These include aspirin, ibuprofen, of traumatic iritis developing. Steroids causes.1,2 Whenever possible, correcting toradol and tramadol. These medica- are NOT always necessary and should be any underlying problem will often pro- tions provide both analgesic as well as avoided initially.2 vide immediate relief and prevention is anti-inflammatory effects. Analgesics If using a bandage lens, make sure that critical in many cases to maintain normal such as acetaminophen lack the anti- you are using a lens of appropriate Dk/t to corneal clarity.2 inflammatory component. The above reduce the likelihood of corneal swelling. anti-inflammatory medications can be Avoid bandage lenses if injury involves Etiology prescribed in combination with narcotic plant material or false fingernails.1,2 Major causes of exposure keratopathy analgesics such as codeine or hydroco- Patching is rarely necessary. Never relate to lid malposition or deformity (eye- done. Cycloplegic agents should be pre- patch contact lens related abrasions or lid scarring from trauma or herpes zoster), scribed to paralyze the and injuries involving vegetative material or ectropian, or chemical burns.1,2 Other thus decrease ocular pain. Mild abrasion false fingernails. Patients should be re- causes stem from lid surgery (especially pto- cases can be managed with cyclopentolate evaluated within 24 hours.2 sis repair and blepharoplassty), nocturnal 1 percent,4 while more severe presenta- Encourage the use of nighttime , sedation and altered mental tions may require scopolamine 0.25% or hyperosmotic ointments up to three-six status, proptosis or cranial nerve palsies homatropine 2% or 5%.5,6 months post insult in cases involving a that affect the lid or eye.2 Fortunately, the cornea heals very significant abrasion. rapidly, but keep in mind that recurrent Treatment corneal erosion is possible even months References A careful medical history may uncover to years later.1,6 Lesions that are purely 1.Arunagiri G, Trikha R. Corneal Abrasions, Contusions, previous Bell’s palsy, lid surgery, anterior Lacerations, and Perforations. IN:Roy FH, Fraunfelder FW 2 epithelial often heal quickly and com- and Fraunfelder FT: Current Ocular Therapy. Saunders/ segment trauma or thyroid disease. Careful pletely without scarring. The presence Elsevier, New York,2008, pp. 359-62. evaluation should include assessment of of subepithelial infiltration may be a 2.Cullom RD, Chang B. Trauma: Corneal Abrasion. In: eyelid closure/laxity and corneal exposure. Always check to be certain there is no evi- dence of reduced corneal sensation increas- ing the risk of corneal complications.2 A slit lamp examination will often uncover any tear film abnormalities, corneal integrity issues or other external or anterior chamber reaction.2 Lubrication is essential for any sedated or obtunded patient.2 Artificial tears, lubricating ointments and gels are the mainstay of treatment. Punctal plugs can also be used when necessary. Eyelid taping and patching can be tried when the condi- tion is believed to be temporary. In severe, recalcitrant cases, with progressive corneal deterioration, eyelid reconstruction, partial tarsorrhaphy and amniotic membrane trans- plants can be beneficial.2 Orbital decompres- sion for proptosis and eyelid gold weights Corneal foreign body Corneal abrasion for seventh nerve palsies can be helpful.2

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001_ro0111_Corneal Atlas.indd 17 12/29/10 5:10 PM Recommendations conjunctiva. Additional symptoms include thetic is applied to the eye. Multiple Close observation is necessary when an photophobia and lacrimation. A slit lamp superficial foreign bodies may be irri- infection is present or a high probability examination will reveal a single or multiple gated.1 Broad spectrum topical antibiot- for infection exists. foreign body. Metallic corneal foreign ics should be used to treat the resultant Floppy eyelid syndrome and body will produce rust. The eye is injected defect after assessing the size of the Parkinson’s disease can also cause a poor with eyelid edema and punctate keratopa- defect1 (see “Corneal Abrasion” section for blink and result in exposure staining.2 thy is seen with a foreign body under the a more complete discussion). Similar treat- Vaseline petroleum jelly preparations lid. An anterior chamber reaction is pos- ment employed for any epithelial defect applied to the periocular skin can be ther- sible with any significant invovlement.1 or abrasion can be used for pain manage- apeutic in certain cases of ectropian and ment. Conjunctival foreign body can may obviate the need for surgery. usually be removed successfully using a cotton-tipped applicator soaked in topical References 1 1. McMonnies C: Incomplete blinking: exposure keratopa- anesthetic or fine forceps. Residual and thy, lid wiper epitheliopathy, dry eye, refractive surgery not easily accessible conjunctival foreign and dry contact lenses. Contact Lens and Anterior Eye, bodies may sometimes be left without 30(1), 37-51. undue harm unless they are infectious or 2. Ehlers JP and Shah CP. Exposure Keratopathy. In: 1 Ehlers JP and Shah CP eds. The Wills Eye Manual: Office pro-inflammatory. and Emergency Room Diagnosis and Treatment of Eye Disease. Philadelphia, PA: Wolters/Kluwer/JB Lippincott, Recommendations 2008: 55-6. Carefully examine the anterior chamber and for any signs of intraocular for- FOREIGN BODY eign body. A low intraocular pressure or A variety of materials in the environ- anterior chamber shallowing effects may ment resulting in foreign body of the eye indicate corneal penetration.1 can be found on the surface of the cornea Any infiltrate suggesting an infectious or conjunctiva, or even be intraocular/ process must be managed with appropri- intraorbital.1,2 Fortunately, the majority Corneal laceration ate antibiotic therapy.1 of foreign bodies encountered in clini- Remove any rust as completely as pos- cal practice lodge on either the cornea or Treatment sible. This might require allowing time for conjunctiva and do not enter the eye or A careful history will determine the the rust to migrate to the surface of the . A dilated eye examination must be mechanism of injury. Some attempt cornea with removal of the rust after sev- performed to rule out any posterior seg- should be made to determine the size, eral days in order to minimize scarring.1 ment involvement and appropriate testing shape weight, velocity, force and com- such as a B-scan ultrasonography, com- position of the object.1 Visual acuity puted tomography (CT scan) of the orbit assessment should be performed before ICD-9 Codes or ultrasonographic biomicroscopy (UBM) any procedure is attempted. Topical • 930.0 corneal foreign body to rule out an intraocular or intraorbital anesthetic agents can control pain and • 930.1 foreign body in the conjunctival foreign body should also be done.1 blepharospasm.1 sac Slit lamp examination will determine • 930.8 foreign body in other and com- the location, depth and whether there bined sites on external eye ICD-9 Codes are any self-sealing lacerations. Evert the • 370.34 exposure keratoconjunctivitis and inspect carefully the fornices. With conjunctival laceration be certain References • 351.0 Bell’s palsy 1. Ehlers JP and Shah CP. Corneal and Conjunctival Tenon’s membrane is intact to rule out Foreign Bodies. In: Ehlers JP and Shah CP, eds. The Wills scleral laceration or perforation of the Eye Manual: Office and Emergency Room Diagnosis and Presentation .1 Treatment of Eye Disease. Philadelphia: Wolters/Kluwer/ JB Lippincott, 2008: 16-18. Patients will generally provide a history Corneal foreign body can be removed 2. Onofrey B: Superficial ocular foreign body. In: Onofrey of trauma and foreign body sensation with by use of a fine forceps or foreign body BE, Skorin L and Holdeman NR eds. Ocular Therapeutics any foreign body of the cornea and/or spud at the slit lamp after topical anes- Handbook. Lippincott-Raven, Philadelphia 1998: 303-4.

Chemical

Toxic/Solution Keratitis sensation and photophobia. The condition less severe adverse ocular response of dif- Chemical toxicity can result from any is generally bilateral and disappears after fuse punctate staining and conjucntival contact lens solution, and care products removing the offending agent. redness has been associated with wearing are an under-recognized cause of intoler- silicone hydrogel lenses when using cer- ance to contact lens wear. A wide range of Etiology tain multipurpose disinfecting solutions.1 signs and symptoms are possible ranging Virtually any contact lens care product from mild sensitivity from a micro-punc- has the potential to create a toxic effect Presentation tate keratopathy to significant discomfort to the ocular surface, especially inad- Patients experiencing a toxic response as a result of diffuse corneal staining. The vertent application of non-neutralized will often present with symptoms of patient may experience a foreign body hydrogen peroxide directly in the eye. A stinging, tearing, burning, dryness and

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001_ro0111_Corneal Atlas.indd 18 12/29/10 5:10 PM a decreased wearing time. Signs include of chemical contact.2,3 Ocular burns rep- redness, conjunctival chemosis, follicular resent 7%-18% of ocular trauma. The vast response, variable corneal staining pat- majority are chemical burns that occur in terns and infiltrates. the industrial/occupational setting.4 Treatment Etiology Palliative therapy should include the Any noxious agent or radiant energy use of artificial tears (non-preserved) or (thermal or ultraviolet) has potential to irri- gels/ointments and antibiotic prophylaxis tate/injure the ocular surface and produce when indicated for more severe forms other more sever forms of anterior segment of coalesced corneal staining. Topical abnormality. This includes alkali (i.e. lye, corticosteroids or antibiotic/steroid com- cements, plasters, airbag powder), acids, sol- 3 Chemical toxicity secondary to multiple topical binations may be warranted especially vents, detergents, and irritants (i.e. mace. antimicrobial medications when there is an infiltrative response Burns damage tissues primarily by denatur- assuming the risk of corneal infection ing and coagulating cellular proteins and has been carefully considered and ruled through vascular ischemic changes.1-4 range of findings will be influenced by the out. A change in solution used is advised • Thermal burns: Injury from radiant severity of the injury but may include par- to remove the offending agent and some energy results from contact with hot liq- ticles in the fornix, conjunctival inflamma- clinicians will switch from a multipurpose uids, gases or molten metal. Cell death tion, perilimbal/limbal ischemia, corneal solution to an oxidative system. from thermal burns is generally limited epithelial defects, stromal haze, anterior to the superficial epithelium, but thermal chamber reaction, adnexal damage/scar- Recommendations necrosis and deeper penetration can occur.4 ring, increased intraocular pressure, peri- Some mild forms of toxicity are barely • Ultraviolet burns: Punctate keratitis ocular skin burns and corneal perforation/ detectable and the use of vital stain is results from an epithelial injury. Delayed melt.3,4 Severe burns may also cause a pro- essential in evaluating patients who are pain is secondary to actinic keratosis.3 nounced chemosis, conjunctival blanching symptomatic with lens wear. • Alkali burns: Since alkali substances and local necrotic resulting Eyes that experience solution toxicity are more lipophilic, they penetrate more from direct penetration of alkali through are more likely to experience a corneal rapidly than acids.1,3 The damaged tissues the .2,3 infiltrative event.1 stimulate an inflammatory response that damages the tissue further by release of Treatment proteolytic enzymes (liquefactive necro- The initial physical examination should ICD-9 Codes sis) and alkali substances can pass into assess of potential life threatening injuries. • 370.21 Punctate keratitis the anterior chamber rapidly exposing the Initial examination of the eye may be limited • 370.3 Certain types of keratoconjunc- crystalline lens, ciliary body, and trabecu- to pH values and acuity determination.2,3 tivitis lar meshwork.3,4 When the pH value is After copious irrigation for 20-30 minutes • 370.4 Other and unspecified kerato- above 11.5, irreversible damage occurs.4 with saline or water, a full ocular examination conjunctivitis Acid burns: Acid burns cause protein is essential.3 Fluorescein and pH evaluation coagulation of the epithelium, thereby is necessary after a short equilibration period. References limiting in most cases further penetra- Ocular irrigation with lactated Ringer’s solu- 1. Carnt N, Jalberty J, Stretton S et al: Solution toxicity tion and limiting progression beyond the tion or other available intravenous solutions in soft contact lens daily wear associated with corneal 4 inflammation. Optometry and Vision Science: superficial cornea. should be continued in the emergency facil- April 2007 84 (4): 309-315. ity. Attention should be given to the clarity Presentation of the cornea, degree of limbal ischemia, and Patients will often give a history of a liq- intraocular pressure. Lid eversion is impor- CHEMICAL BURNS uid or gas being splashed or sprayed into tant to detect and eliminate any particles or Chemical injuries have the poten- the eye or of particles falling into the eye.4 foreign bodies. Immediately following the tial to permanently damage the ocu- The local Poison Control Center may be injury, it is important to estimate and grade lar surface (unilateral or bilateral). an invaluable resource in determining the the severity of limbal stem cell injury and Pathophysiological cascades that may nature of the chemical when unknown.3 debride any necrotic epithelium to allow nor- influence the final visual outcome Common complaints include: pain, for- mal tissue to re-epithelialize.1 The grading can include: 1) ocular surface injury and eign body sensation, blurred vision, exces- be accomplished by assessing the degree of repair, 2) stromal matrix repair and or sive tearing and photophobia.2-4 A wide limbal, conjunctival, and scleral ischemia and ulceration and 3) corneal inflamma- tion.1,2 Ocular burn severity correlates to exposure duration and noxious agent.4 Specifically, chemical burn severity relates to pH, duration, solution quantity and permeability.3 Ocular burns caused by acids are generally less severe com- pared to alkali burns due to the natural buffering capacity of the corneal stroma and the barrier to penetration formed by coagulated epithelial cells.1 Immediate therapy should include prompt irrigation and removal of any remaining reservoir Conjunctival alkali burn Acid burn with sloughed epithelium

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001_ro0111_Corneal Atlas.indd 19 12/29/10 5:24 PM necrosis, and by evaluating the penetration of the noxious agent by assessing the clarity of the stroma and any additional anterior segment abnormalities.1,2 If the limbus is affected significantly, the cornea may develop epithelial defects and conjunctival invasion onto the cornea.3 Depending on severity, therapeutic agents include antibiotic for significant epithelial defects, , topical ste- roids and anti-glaucoma agents when IOP is elevated.2-4 Using steroids beyond seven Alkali burn four months after injury Severe corneal edema requiring PKP six years after days after severe burns is controversial and alkali burn will occasionally result in perforation and bandage contact lenses, aprotinin (inhibits ulceration of the cornea due to the effects proteinase activity), topical heparin (re- epithelium has sloughed, Bowman’s layer on wound repair.1 Topical artificial tears opening of occluded blood vessels, ascor- remains and takes up fluorescein poorly.3 and lubricating ointments play a significant bate and citrate for alkali burns.1 With any Closely monitor IOP. An immediate role in managing these cases. Other cases melting processes of the cornea, collagenase rise in pressure can result from collagen may require lysis of conjunctival adhesions, inhibitors, such as tetracycline, and tissue deformation and shortening that directly adhesives may be used.3 Glaucoma follow- affects the anterior chamber. Prolonged ICD-9 Codes ing chemical burns will generally respond increases in IOP are directly related to the 4 • 370.24 photo keratitis to conventional agents (oral and topical). degree of anterior chamber inflammation. • 940.1 chemical burn of the eyelid and Additionally, emergent patch grafts may be necessary. Added measures such as References periocular area 1. Wagoner MD: Chemical injuries of the eye: cur- conjunctival or limbal stem cell transplants • 940.2 alkaline chemical burn of cor- rent concepts in pathophysiology and therapy. Surv from the fellow eye may be necessary for Ophthalmol. 1997; 41(4): 275-279. nea and conjunctival sac injuries that fail to heal within several 2. Roy FH: Alkaline Injury. IN:Roy FH, Fraunfelder FW • 940.3 acid chemical burn of cornea weeks to months.3,4 and Fraunfelder FT: Current Ocular Therapy. Saunders/ and conjunctival sac Elsevier, New York,2008, pp. 277-78. 3. Ehlers JP and Shah CP. Chemical Burn. In: Ehlers • 940.4 other burn of cornea and con- Recommendations JP and Shah CP eds. The Wills Eye Manual: Office junctival sac If an epithelial defect is not appreciated and Emergency Room Diagnosis and Treatment of Eye • 940.5 burn with resulting rupture and Disease. Philadelphia, PA: Wolters/Kluwer/JB Lippincott, initially, re-instill fluorescein; the defect 2008: 12-15. destruction of eyeball may be slow to take-up dye. If the entire 4. http://emedicine.medscape.com/article/798696-overview.

Inflammatory Corneal Conditions

STAPH MARGINAL KERATITIS/CLPU often oval, and may be associated with to moderate conjunctival injection near Etiology corneal vascularization. the corneal infiltrate and a round, focal A contact lens-induced peripheral peripheral infiltrate approximately 2mm ulcer (CLPU) typically presents as a single Presentation or less. The overlying small epithelial well-circumscribed, circular, dense focal Patients may complain of redness, defect stains with fluorescein. Anterior corneal infiltrate involving the anterior discomfort, light sensitivity, tearing and chamber reaction, if present, is very mild. corneal layers.1 Compared to the much foreign body sensation. These symptoms A significant anterior chamber reaction more feared and complicated microbial are milder than in microbial keratitis; raises the suspicion of microbial keratitis. keratitis, it is sometimes difficult to dis- however, suspicion must always be high tinguish between a CLPU and microbial in contact lens-wearing patients of a Treatment keratitis, so microbial keratitis is always possible underlying microbial cause. Slit- The initial management of CLPU considered part of the differential diagno- lamp examination will demonstrate mild involves discontinuing contact lens wear. sis. Differentiating a contact lens-induced Patients are often started on topical anti- peripheral ulcer (CLPU) from early stage biotics such as a fourth-generation fluoro- microbial keratitis (MK) is primarily quinolone and followed with serial exam- based on clinical judgment rather than inations for evidence of either improve- on microbiologic or histopathologic ment or worsening of the condition to investigations.2 However, there is often rule out microbial keratitis. Topical ste- an overlap in the signs and symptoms roids should generally be withheld until that can complicate the diagnosis. A criti- the epithelial defect is healed and there is cal sign, however, is the response of the no evidence of fungal, protozoan, or her- presentation immediately after lens wear petic infection. In staph-induced marginal is discontinued.3 CLPUs are different keratitis where severe inflammation exists, from peripheral marginal ulcers caused by antibiotic and corticosteroid combina- S. aureus exotoxins that are often found tion drops or ointments can be rubbed in the corneal periphery, which are more Pemphigoid into the lid margins following lid scrubs.

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001_ro0111_Corneal Atlas.indd 20 12/29/10 5:28 PM is the number one reason patients discon- dry eye therapy. Patient symptoms and tinue contact wear. Approximately 34% of clinical signs should be considered when patients discontinue contact lens wear at deciding on therapeutic intervention. least once, most frequently because of dry The management of dry eye disease eye symptoms. (DED) encompasses both pharmacologic and non-pharmacologic approaches, Presentation including avoidance of exacerbating fac- Physical examination includes visual tors, eyelid hygiene, tear supplementa- acuity measurement, external examination, tion, tear retention, tear stimulation, and and slit-lamp biomicroscopy.6 Additional anti-inflammatory agents.8 Artificial tears diagnostic tests may be performed to are the mainstay of DED therapy but, assess tear film instability, ocular surface although they improve symptoms and damage, and aqueous tear flow. Tear objective findings, they do not resolve film instability is commonly evaluated the underlying inflammation in DED. by performing a tear film break-up time Topical corticosteroids are effective anti- Contact lens acute red eye with peripheral infiltrate test. Ocular surface damage is commonly inflammatory agents, but are only used assessed by staining with rose bengal, lissa- short-term because of their adverse-effect mine green, or fluorescein dye. Abnormal profiles. Topical cyclosporine—currently Oral therapy with tetracycline 250mg corneal and/or conjunctival staining pat- the only approved pharmacologic treat- four times a day or doxycycline 100mg terns, observed on slit-lamp examination, ment for DED—is safe for long-term twice a day or minocycline 50mg twice a are a sign of damage. Aqueous tear flow use and is a disease-modifying therapy. day may be needed for more severe infec- is commonly assessed by performing a Treatment selection is guided primarily tions. The lesion generally heals with a Schirmer test. While helpful in making the by DED severity.9 Replacement of tear small, mid-stromal scar and recurrence is diagnosis, diagnostic test results generally volume with nonpreserved wetting agents not uncommon. correlate poorly with symptoms.7 and standard typical anti-inflammatory corticosteroid and/or cyclosporine A ICD-9 Codes Treatment continues to be central current conven- There is no single method for deter- tional therapy for dry eye.10 Autologous • 370.00 Corneal ulcer, unspecified mining if a patient is a candidate for serum eye drops have been reported to • 370.01 Marginal corneal ulcer be effective for the treatment of severe dry eye-related ocular surface disorders DRY EYE (Sjögren’s syndrome).11 Etiology From the 2007 DEWS Report: “Dry eye ICD-9 Codes is a multifactorial disease of the tears and • 370.33 Keratoconjunctivitis sicca, not ocular surface that results in symptoms of Sjogren’s discomfort, visual disturbance, and tear film instability with potential damage to the ocu- • 370.23 Filamentary keratitis lar surface. It is accompanied by increased osmolarity of the tear film and inflamma- UVEITIS tion of the ocular surface.”4 It is a common Etiology disorder that especially affects adults and Anterior uveitis is an important condi- women and can cause quality of life impair- tion in primary eye care. It is the most ment comparable to migraine, shortness common form of uveitis encountered in of breath and chronic renal insufficiency, general ophthalmic with acute anterior depending on its symptoms or complica- uveitis (AAU) occurring significantly tions.5 There are two etiopathogenic dis- more often than chronic anterior uveitis tinctions of dry eye: aqueous deficient and (CAU) or posterior uveitis.12 evaporative. There are numerous causes for each. Dry eye is the single most common Salzman’s nodular degeneration Presentation complaint among contact lens wearers. It Symptoms of unilateral pain, pho- tophobia, redness and watering develop over one to two days, with little or no effect on vision.13 Pain and photopho- bia may precede slit lamp signs, due to unseen ciliary body inflammation. Signs depend on the severity of the inflamma- tion but typically include circum-limbal flush, miotic , anterior chamber cells and flare, and small, fine keratic precipi- tates (KP). The pupil may appear slug- gish and may be small and irregular. In more severe attacks, posterior synechiae, Filamentary keratitis and culture positive fungal peripheral anterior synechiae, corneal ulcer in Sjogren’s syndrome Peripheral corneal ulcer edema, spill-over vitritis and macular

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001_ro0111_Corneal Atlas.indd 21 12/29/10 5:11 PM edema may be seen. The intraocular pres- ized injection at 12 o’clock with associated subepithelial infiltrates may be found on sure (IOP) generally falls slightly with loose and boggy bulbar conjunctiva can be the superior aspect of the cornea in associa- attacks but occasionally it may increase.14 observed. An irregular epithelial surface, tion with hyperemia of the superior bulbar punctate staining with fluorescein, and conjunctivae. There may be significant Treatment neovascularization and fibro-vascular pannus In the majority of cases of AAU, espe- extending into the superior cornea. Evert the cially those of mild to moderate intensity, eyelids on all contact lens patients, paying topically applied steroids are the mainstay of careful attention to the bulbar and tarsal treatment.15 Dosage regimens for topically conjunctivas at the superior limbus. applied steroids depend on the severity of AAU but all strategies must include aggressive Treatment initial treatment with the goal of bringing the Case management for CLSLK is inflammation under control quickly. Hourly straightforward. Discontinuation of instillation for the first few days is typical. contact lens wear and treatment with fre- A loading dose to achieve a therapeutic quent preservative-free ocular lubricants concentration at an early stage is often recom- is the initial therapy. In most cases, this mended.16 Mydriatic/cyclopegic agents may palliative treatment will suffice. In more also be added to reduce pain and prevent the severe presentations where the patient development of posterior synechiae. is experiencing significant discomfort, it might be necessary to concurrently treat the patient with steroid drops during the ICD-9 Codes day and steroid ointment in the evening. • 364.00 Acute and subacute iridocycli- Dosing schedule will vary depending on tis, unspecified the case presentation. The treatment for • 364.01 Primary iridocyclitis SLK is generally more involved and can • 364.02 Recurrent iridocyclitis require thermocautery, conjunctival resec- • 364.05 Hypopyon tion or chemical cauterization with silver nitrate solution.

CONTACT LENS SUPERIOR LIMBIC References 1. Sweeney DF, Sankaridurg PR, Holden B, et al. A KERATOCONJUNCTIVITIS typical presentation of contact lens induced peripheral Etiology ulcers–multiple focal corneal infiltrates. ARVO poster CLSLK and SLK are inflamma- 2002. tory conditions that affect the superior 2. Aasuri MK, Wenkata N, Kumar Vm. Differential diag- nosis of microbial keratitis and contact lens-induced bulbar conjunctiva and adjacent cor- peripheral ulcer. Eye Cont Lens 2003;29: S60-62. neal surface. Contact Lens Superior 3. Diec J, Carnt N, Tilia D, et al. Prompt diagnosis and Limbic Keratoconjunctivitis (CLSLK) treatment of microbial keratitis in a daily wear lens. is recognized as a completely separate Optom Vis Sci 2009; 86(7):E904-07. 4. 2007 Report of the International Dry Eye Workshop event from Theodore’s Superior Limbic (DEWS). The Ocular Surface 2007; 5(2):75-88. Keratoconjunctivitis (SLK). CLSLK is 5. Fonseca EC, Arruda GV, Rocha EM. Dry eye: identified in patients wearing soft lenses etiopathogenesis and treatment. Arq Bras Oftalmol by superior corneal staining combined Staph marginal ulcer 2010;73:197-203. 6. American Academy of Ophthalmology. Preferred prac- with tarsal and superior limbal hypertro- tice pattern: . www.aao.org/education/ phy. There may be an association with guidelines/ppp/upload/Dry_Eye_Syndrome-2.pdf. atopy, contact lens-related trauma, hypox- ICD-9 Codes 7. Perry HD. Dry eye disease: Pathophysiology, classi- fication and diagnosis. Am J Manag Care 2008;14:S79- ia, hypersensitivity responses to proteins • 370.21 Punctate keratitis deposited on contact lens and chemical S87. • 371.82 Corneal disorder due to 8. Behrens et al. Dysfunctional Tear Syndrome: A Delphi preservatives, especially thimerosal in lens contact lens Approach to Treatment Recommendations. Cornea 2006; care systems. SLK on the other hand is 25(8):900–07. • 372.10 Chronic conjunctivitis, seen in older populations of women and 9. Lemp MA. Management of dry eye. Am J Manag unspecified. Care. 2008;14:S88-S10. might be related to thyroid eye condi- 10. Gumus K, Cavanagh DH. The role of inflammation tions or other autoimmune diseases. and antiinflammation therapies in keratoconjunctivitis sicca. Clin Ophthalmol 2009;3:57-67. Presentation 11. Quinto GG, Campos M, Behrens A. Autologous serum for ocular surface diseases. Arq Bras Oftalmol Both conditions will manifest with 2008;71(6 Suppl):47-54. punctate staining of the superior corneal 12. Chang JH, McCluskey PJ, Wakefield D. Acute anterior epithelium, although CLSLK is often a more uveitis and HLA-B27. Surv Ophthalmol 2005;50:364–88. aggressive presentation. SLK is typically a 13. Hogan MJ, Kimura SJ, Thygeson P. Signs and symp- toms of uveitis. Am J Ophthalmol 1959;47:155-70. bilateral condition and is clearly evident 14. Gutteridge IF, Hall AJ. Acute anterior uveitis in pri- upon visualization. CLSLK is usually mon- mary care. Clin Exp Optom 2007;90:70-82. ocular with tremendous variability of presen- 15. Yanoff M, Duker JS, eds. Ophthalmology, 3rd ed. tation. Patients with CLSLK may complain Maryland Heights, MO, Elsevier, 2009. 16. Ehlers JP, Shah CP, eds. The Wills Eye Manual: of contact lens intolerance, light sensitivity, Office and Emergency Room Diagnosis and Treatment burning, redness, watering and pain. Upon of Eye Disease, 5th Ed. Philadelphia, PA: Lippincott, lifting the upper lid, an intense area of local- Giant papillary conjunctivitis Williams and Wilkins, 2008.

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