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206 Corneal Pigmentation

Recommended Monitoring
Corneal degeneration and lipid keratopathy
VetBooks.ir diseases, respectively.
require management of ocular and systemic

PROGNOSIS & OUTCOME
Good. Corneal dystrophy may be slowly
progressive but rarely interferes with vision.
Corneal degeneration and lipid keratopathy may
resolve or remain static if underlying conditions
are treated.

PEARLS & CONSIDERATIONS
Comments
CORNEAL DYSTROPHY Note the oval, white, glittery area in the axial cornea in this Cavalier King Charles Corneal dystrophy is the most common condi-
spaniel. (Courtesy Diane Hendrix, DVM, University of Tennessee.) tion causing corneal lipid infiltrates in dogs.
Clients planning to breed dogs with this condi-
tion should be informed that it is a heritable
trait and Orthopedic Foundation for Animals
• Serum chemistry panel (including fasting ophthalmic preparation (0.4%-3.75% q (OFA) eye evaluations are recommended.
cholesterol, triglycerides if lipid keratopathy 6-8h) can be used in an attempt to chelate
is suspected) the mineral. Technician Tips
○ Corneal dystrophy: normal • Lipid keratopathy: address underlying Lipid deposits in the cornea are usually not
○ Corneal degeneration: normal systemic disease painful and fluorescein negative. If the patient
○ Lipid keratopathy: hyperlipidemia has ocular pain or corneal ulceration, additional
Chronic Treatment evaluation to identify the underlying ocular
Advanced or Confirmatory Testing In rare instances dense lipid deposits can disease and topical ophthalmic medications are
• Referral to a veterinary ophthalmologist for cause visual deficits. Referral to a veterinary likely required.
confirmation by slit-lamp biomicroscopy ophthalmologist for surgical removal by a
• Thyroid panel, adrenal function evaluation superficial keratectomy is possible. Deposits Client Education
if indicated may re-form after surgery. Corneal dystrophy is a heritable trait, and dogs
used for breeding should be evaluated by an
TREATMENT Nutrition/Diet ophthalmologist for disease conformation and
Low-fat diets are recommended in cases of recommendations.
Treatment Overview hyperlipidemia (lipid keratopathy). Dietary
Goals of treatment: restrictions are noted anecdotally to decrease SUGGESTED READING
• Minimize further lipid infiltration if possible. or control lipid infiltrates due to corneal Crispin S: Ocular lipid deposition and hyperlipopro-
• Manage any underlying systemic disease. dystrophy or corneal degeneration in some teinemia. Prog Retin Eye Res 21:169-224, 2002.
dogs.
Acute General Treatment AUTHOR: Erin M. Scott, VMD, DACVO
• Corneal dystrophy: none required Drug Interactions EDITOR: Diane V. H. Hendrix, DVM, DACVO
• Corneal degeneration: address underlying Long-term use of topical corticosteroids
ocular disease may cause or exacerbate corneal lipid infil-
○ If calcium component is present, topical trates, a condition known as corticosteroid
application of disodium EDTA in an keratopathy.

Corneal Pigmentation Client Education
Sheet

BASIC INFORMATION • Cats: corneal sequestrum (p. 208): primarily • Extensive pigmentation may cause reduced
brachycephalic breeds or absent menace response.
Definition • Other findings will vary depending on the
Brown to black discoloration of the cornea, Clinical Presentation underlying cause.
usually due to the presence of melanin HISTORY, CHIEF COMPLAINT
• Brown discoloration of cornea Etiology and Pathophysiology
Epidemiology • Concurrently: redness of the conjunctiva, • Epithelial and stromal pigmentation
SPECIES, AGE, SEX ocular discharge, ocular pain, reduced vision ○ Melanin is produced in the cornea by
• Dogs: pigmentary keratitis: brachycephalic melanocytes in response to chronic
breeds, especially pug breed; pannus (chronic PHYSICAL EXAM FINDINGS corneal irritation from desiccation (p.
superficial keratitis) (p. 748): large-breed • Brown or black discoloration of the corneal 568), mechanical trauma, or secondary
dogs, especially German shepherd breed epithelium, stroma, or endothelium to chronic inflammation in response

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