Term
| How does porr or absent eyelid function affect the cornea? |
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Definition
| -exposure and poor distribution of tear film |
|
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Term
| How does abnormal eyelid position affect the cornea? |
|
Definition
| -exposure and poor distribution of tear film |
|
|
Term
| How do aberrent cili affect the cornea? |
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Definition
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Term
| How does conjunctivitis affect the cornea? |
|
Definition
| -potential effect on goblet cells will alter mucin tear film component and affect corneal nutrition |
|
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Term
| How does an inadequate tear fim affect the cornea? |
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Definition
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Term
| How does intraocular disease affect the cornea? |
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Definition
| -alters the composition of the aqueous humor which affects corneal nutrition |
|
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Term
| What do we automatically do when corneal pathology is present? |
|
Definition
-Schirmer tear test: to rule out dry eye
-Fluorescein stain |
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Term
| What happens with corneal edema of superficial origin? |
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Definition
| -loss of epithelial barrier causes fluid from tear film to be absorbed |
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Term
| What happens with corneal edema of deep origin? |
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Definition
-loss of endothelial cell function
-aqueous from anteiror chamber is absorbed |
|
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Term
| What does cornea edema look like? |
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Definition
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|
Term
| Does corneal disease indicate active or inactive disease? |
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Definition
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Term
| What cells are prone to corneal cellular infiltrate? What does it look like? |
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Definition
-neutrophils, eosinophils, neoplastic cells, organisms
-white, crream, or yellow in color |
|
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Term
| What is commonly associated with corneal disease? Do cellular infiltrate indicate active or inactive disease? |
|
Definition
-vascularization
-active disease |
|
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Term
| What are some examples of crystalline or mineral infiltrate? What does it look like? |
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Definition
-cholesterole, calcium
-white, sparkling appearance |
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Term
| Does fibrosis indicate active or inactive disease? |
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Definition
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Term
| IS fibrosis have permanent or transient physical effects? |
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Definition
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Term
| What is the difference between the appearance of active and chronic vascularization? |
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Definition
-active is branching
-chronic is a single or maybe two branches |
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Term
| What is the common name for active vascularization? What is the common name chronic vascularization? |
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Definition
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Term
| What is the technical term for melanosis? |
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Definition
|
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Term
| What happens during corneal pigmentation? |
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Definition
| -melanocytes migrate into the cornea from the limbal conjunctiva in response to chronic disease or chronic irritation |
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Term
| How can corneal pigmentation affect vision? |
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Definition
| -depends on size and location but can partially intere with vision |
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Term
| What is the very first thing you determine with corneal disease? How do we determine this? |
|
Definition
-ulcerative vs non-ulcerative
-Fluorescein Stain Test |
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Term
| What are the etiologies of corneal ulcers? |
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Definition
-hair irritatin: entropion, ectopic cilia, large distichia
-lid dysfunction: CN7 paralysis
-exposure: proptosis, exophthalmia, extropion
-KCS
-foreign body
-epithelial basement membrane disease
-chemical
-infectious: herpes virus, Moraxella bovis
-idiopathic |
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Term
| What is an epithelial ulcer? How will it respond to a Fluorescin Stain test? |
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Definition
-epithelium is gone exposing surface of strome without a visible dibot in the cornea
-positive on F. stian |
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Term
| What is a stromal ulcer? How will it respond to a Fluorescein Stain Test? |
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Definition
-epithelium and a variable amount of stroma are gone and a divot is visible
-positive on FST |
|
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Term
| What is a descemetocele? How will it respond to a Fuorescein Stain Test? |
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Definition
-epi and stroma are GONE expsoing clear Descemet's membrane
-only the sides show green with FST |
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Term
| What does a corneal perforation look like? |
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Definition
| -iris usually pops through the cornea |
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Term
| What are some of the complications of corneal ulcers? |
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Definition
-infection
-keratomalacia
-anterior uveitis
-perforation of the cornea |
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Term
| What is Keratomalacia? What organism is known for causing this? |
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Definition
-kertocytes, neutrophils, and infectious organisms can release collagenase enzymes that caus rapid degradation of stromal collagen resulting in MELTING of the cornea
-especially Pseudomonas |
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Term
| What causes anterior uveitis in the case of corneal ulcers? |
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Definition
| -any wounding of the cornea immediates causes a release of prostaglandins from anterior ucea, cause leaky blood vessels in the uvea, miosis, and ciliary muscle spasm |
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Term
| What are the clinical signs of corneal ulcers? |
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Definition
-PAIN: blepharospasm, rubbing
-Discharge: tearing that becomes mucopurulent
-inflamed conjunctiva
-corneal edema
-vascularizationtoward th eulcer
-possible cellular infiltrates |
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Term
| In correct order, what diagnostics do we run on corneal ulcers? |
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Definition
-Culture: if you can see cellular infiltrates
-STT: if looks dry
-Fluorescein stain: always
-Cytology: if a horse or hasn't healed after treatment |
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Term
| What are the indications for a culture for a corneal ulcer? |
|
Definition
-any stromal ulcer with cellular infiltrate or hypopyon
-any stromal ulcer in a horse |
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Term
|
Definition
| -WBC mass in anterior chamber |
|
|
Term
| What are the indications for a STT of a corneal ulcer? |
|
Definition
| -in dog, dry appearance or thick mucoid discharge to check for KCS |
|
|
Term
| What do we use to facilitate the exam of a corneal ulcer? |
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Definition
|
|
Term
| What are the indications for Fluorescein stain of a corneal ulcer? |
|
Definition
-ALWAYS
-taken up by exposed stroma, not Descemet's membrane |
|
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Term
| What are the indications for a cytology of a corneal ulcer? |
|
Definition
-any stromal ulcer in SA that is getting worse in spite of appropriate therapy
-any stromal ulcer in a horse
-any epi ulcer in a horse that is not steadily improving |
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Term
| What are the principles behind corneal ulcer treatment? |
|
Definition
-Must find underlying cause when possible
-support the nromal corneal healing process with medical therapy (epi proliferation, stromal repair by fibroblasts) and antibiotics to prevent infection
-blood vessels are GOOD
-NEVER USE TOPICAL STEROIDS
-do NOT use topical NSAIDs
-treat concurrent anterior uveitis when present
-recheck ever 2-5 days
-E-collar or eye mask with cups |
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Term
| We never, ever, ever give steroids to corneal ulcer cases. Why not? |
|
Definition
-promote keratomalacia
-inhibit migration of epi cells
-inhibit migration of blood vessels |
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Term
| We never, ever, ever give topical NSAIDs to corneal ulcer cases. Why not? |
|
Definition
-painful applicaiton
-promotes keratomalacia
-no analgesia |
|
|
Term
| IN which breeds are corneal ulcers prone to go terribly wrong? |
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Definition
|
|
Term
| How do we treat epithelial corneal ulcers? |
|
Definition
|
|
Term
| Ho do we treat stromal corneal ulcers? |
|
Definition
-topic antibiotic
-topical atropine
-systemic NSAID
-corneal graftin for deep stromal ulcers
-corneal fracting for descemetocele |
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|
Term
| For deep stromal ulcers, in which situations would we start to consider corneal grafting? |
|
Definition
-worse despite medical therapy
-no or weak vascularization |
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Term
| When can corneal perforations be saved? How do we treat them in this case? |
|
Definition
-pupil visible
-corneal graft, can do just medical management but it will probably rupture |
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|
Term
| If there is no pupil visible with a corneal ulcer, how do we treat it? |
|
Definition
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|
Term
| If we are not sure if we see pupil or not with a corneal perforation, what do we do? |
|
Definition
-stay overnight on ATROPINE, topical antibiotic, systemic NSAID
-keep quiet
-look at it the next morning |
|
|
Term
| How do we treat keratomalacia? |
|
Definition
-Anticollagenase meds: Serum, Doxy, EDTA, Acetylcysteine
-Conjunctival graft |
|
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Term
|
Definition
| -fungal corneal infection |
|
|
Term
| How do we treat keratomycosis? |
|
Definition
|
|
Term
| How do we tell if it is keratomalacia or not? |
|
Definition
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|
Term
| What are some problems with nictitans flap and tarsorrhaphy for corneal ulcers? |
|
Definition
-do not bring in nutrient suppy to aid in corneal healing and repair
-do not provide structural support to the weak cornea
-impede meds getting to the cornea
-do not allow visualization of the cornea so if complications occur you may not know until too late
-often promote rubbing
-exception is cattle and camelids!! |
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Term
| What is the typical sgnalment of indolent epithelial ulcers? |
|
Definition
| -middle aged to older dogs |
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|
Term
| How does an Indolent Epithelial Ulcer present clinically? |
|
Definition
-NON-HEALING epithelial ulcer
-non-adhered epithelium at ulcer margin is PATHOGNOMONIC |
|
|
Term
| Which species gets indolent epithelial ulcers? |
|
Definition
|
|
Term
| What is the etiology of an indolent epithelial ulcer? |
|
Definition
| -abnormality at the level of the epithelial basement membrane/stromal interface preventing normal adherence fo the migrating epi cells |
|
|
Term
| What is the goal of treating an indolent epithelial ulcers? How do you treat indolent epithelial ulcers? |
|
Definition
-goal is to expose healthy stroma
-grid or burr keratotomy
-keratectomy: referral |
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|
Term
| How do we differentiate between superficial and deep foreign bodies? |
|
Definition
| -use a slit beam at 90 degrees from cornea |
|
|
Term
| What is the common superficial corneal foreign body? How do we treat it? |
|
Definition
-plant material seated in epithelium
-remove with praparacoine and moistened Q-tip, treat as superficial ulcer |
|
|
Term
| How do we treat deep corneal foreign bodies? |
|
Definition
-do not remove until under anesthesia and prepared to surgically repair the defect
-can start on atropine systemic NSAID for the secondary uveitis |
|
|
Term
| What are the clinical signs of corneal lacerations? |
|
Definition
-same as corneal ulcer
-if it is very deep the iris may prolapse |
|
|
Term
| How do we treat corneal lacerations? |
|
Definition
-suture it back together
-if deep, may require corneal graft |
|
|
Term
| What are the etiologies of non-ulcerative keratitis? |
|
Definition
-Hair irritation: entropion, ectopic cilia, large distichia
-lid dysfunction: CN 7 paralysis
-exposure: exophthalmia, ectropion
-KCS
-immune-mediated: chronic superficial keratitis or pannus, idipathic |
|
|
Term
| What are the clinical signs of a non-ulcerative keratitis? |
|
Definition
-NOT painful
-cornal vscularization
-+/- edema, callular infiltrate, fibrosis, pigment |
|
|
Term
| What diagnostic tests do we use for non-ulcerative keratitis? |
|
Definition
-schrmer tear test
-fluorescein stain(negative by definition) |
|
|
Term
| How do we treat non-ulcerative keratitis? |
|
Definition
-treat/eliminate the underlying cause for lid, cilia, or KCS etiologies
-medical therapy: corticosteroids (topical), cyclosporine/tacrolimus |
|
|
Term
| Do topical NSAIDs help with nonulcerative keratitis? |
|
Definition
|
|
Term
| What is the classic signalment for chroic superficial keratitis or pannus? |
|
Definition
| -usually in German Shepherds |
|
|
Term
| What is the etiology behind chronic superficial keratitis? |
|
Definition
|
|
Term
| What are the clinical signs of chronic superficial keratitis? |
|
Definition
-starts at the lower, lateral limbus: bilateral
-vascularization, edema, cellular infiltrate, +/- pigment
-will cause blindness if not treated due to fibrosis |
|
|
Term
| How do we treat crhonic superficial keratitis? |
|
Definition
-topical steroids
-topical cyclosporine
-TREATMENT IS LIFELONG |
|
|
Term
| What is corneal lipid acucmulation? |
|
Definition
-axial, fine, refractile crystalline deposits in the superficial stroma
-unilateral or bilateral
-non-painful
-does not affect vision |
|
|
Term
| What is the etiology of corneal lipid accumulation? |
|
Definition
-genetic = no treatment
-secondary to hypercholesterolemia = can improve or resolve by lowering serum cholesterol
-secondary to other corneal disease (lipid degeneration) |
|
|
Term
| In what kind of dog does dystrophic corneal calcification happen? |
|
Definition
|
|
Term
| Describe the process of dystrophic corneal cacification? |
|
Definition
| -crystalline depositis in the superficial stroma => progressing o denser deposits with linear scratch configuration => progressing to a hard, dense mineralized plaque in the stroma and epithelium |
|
|
Term
| How do we treat cornal calcium accumulation? |
|
Definition
-Medical: EDTA ointment
-Surgical: keratectomy and conjunctival graft for the deep ulcer/descemetocele |
|
|
Term
| What is the process of corneal endothelial dysfunction? |
|
Definition
-age-related althou some toy breeds appear more predisposed
-dysfunction/degeneration of the corneal endothelium results in diffuse, full-thickness corneal edema, non-painful
-if severe, bulla can form in the stroma and rupture causing painful epithelial ulcers |
|
|
Term
| How do we treat corneal endothelial dysfunction? |
|
Definition
-5% NaCL ointmet (hyperosmotic)
-severe cases may require surgery |
|
|
Term
| What are the major differential diagnoses for diffuse corneal edema? |
|
Definition
-corneal endothelial dystrophy: no redness, no pain
-intraocular inflammatory disease: redness, discomfort
-glaucoma |
|
|
Term
| What is the common name for a dermoid? |
|
Definition
|
|
Term
| How do dogs and cows get dermoids? |
|
Definition
|
|
Term
| What is thetypical corneal dermoid location? |
|
Definition
|
|
Term
| How do we treat corneal dermoids? |
|
Definition
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