Sclera/Cornea Flashcards
What is the anterior and posterior portion of the fibrous tunic
Anterior: Cornea
Posterior: Sclera
What are the different layers of the sclera
1) Episclera- vessels and nerves
2) Sclera proper- dense fibrous
3) Lamina fusca- inner elastic layer
What is the inner most elastic layer of the sclera
Lamina fusca
What layer of the sclera contains vessels and nerves
cannot be moved
episclera
What is the dense, fibrous later of the sclera
sclera proper
junctional zone between sclera and cornea
limbus
Collagen arrangement in the sclera is ______ while the cornea is _______
Sclera: random
Cornea: ordered
opening in the sclera for the optic nerve
lamina cribrosa
why might the cat and horse be more resistant to optic nerve damage with glaucoma
cats have elastic lamina cribrosa
dogs have a rigid lamina cribrosa which means as globe stretches, ganglion cells get compresses
congenital malformation of the eye causing a defect in the lens, iris, retina, sclera, optic disk
usually optic disk
Coloboma
coloboma is most common in what breeds
Collies- Collie eye syndrome (anomaly) CEA
Australian Shepherds- multiple ocular anomaly (MODS)
multiple ocular anomaly (MODS)
coloboma present in Australian shephards
congenital malformation of the eye causing a defect in the lens, iris, retina, sclera, optic disk
usually optic disk
Collie eye anomaly (CEA)
coloboma present in collies
congenital malformation of the eye causing a defect in the lens, iris, retina, sclera, optic disk
usually optic disk
Coloboma
congenital malformation of the eye causing a defect in the lens, iris, retina, sclera, optic disk
usually optic disk
-Collies and Australian Shephards
ex:
1) Microphthalmia
2) Iris colobomas
3) Optic nerve coloboma
What are different scleral diseases
1) Inflammatory- episcleritis/scleritis
2) Neoplasia- usually arises at limbus
3) Trauma
neoplasia of the sclera typically arises at the
limbus
You take a scleral biopsy to see if the causes is inflammatory or neoplastic, what confirms that it is inflammatory
granulomatous inflammation
What are the 3 types of scleral inflammation
1) Diffuse episcleritis
2) Nodular scleritis
3) Nodular granulomatous episclerokeratitis (NGE)
all look very similar
How does diffuse episcleritis typically present *
“red eye”
rule out other causes of “red eye” (conjunctivitis, uveitis, glaucoma)
What are the clinical signs of diffuse episcleritis *
1) Diffuse episcleral injection (red eye) *
2) Little to no pain or ocular discharge
3) Usually no intraocular abnormalities
4) Peri-limbal corneal edema *
5) Normal or low intraocular pressure
What causes “red eye”
1) Episcleritis
2) Conjunctivitis
3) Uveitis
4) Glaucoma
What commonly causes episcleritis
think its immune mediated inflammation
-present in certain breeds
sub-conjunctival scleral swelling near limbus
adjacent peri-limbal edema
generally painful
nodular scleritis
T/F: episcleritis is typically painful
False
T/F: nodular scleritis is typically painful
True
nodular granulomatous episcleritis (NGE) is most commonly diagnosed in
Collies
T/F: nodular granulomatous episcleritis (NGE) is generally painful
True
Where is nodular scleritis seen
sub-conjunctival scleral swelling near limbus and adjacent peri-limbal edema
Where is nodular granulomatous episcleritis (NGE) seen
involves conjunctiva, sclera +/- adjacent cornea
What are differential diagnoses for nodular granulomatous episcleritis (NGE) and nodular scleritis
neoplasia
How do you treat scleral inflammatory disease
-Strongly consider referral
1) Topical dexamethasone 0.1% solution TID
2) Topical cyclosporing A 2% or tacrolimus 0.02% solution TID
if poor responses to topical
1) Oral prednisone 0.5-2mg/kg PO
2) Oral azothioprine
3) Subconjunctival steroids
4) Cryotherapy
Very likely to recur
Why do you need to refer scleral inflammatory diseases
because they are very likely to recur, some have to enucleate
Needs to be done right because steroids last 8 weeks in eye and if ulcer develops then it could get really bad
treatment looks like:
1) Topical dexamethasone 0.1% solution TID
2) Topical cyclosporin A 2% or tacrolimus 0.02% solution TID
if poor responses to topical
1) Oral prednisone 0.5-2mg/kg PO
2) Oral azothioprine
3) Subconjunctival steroids
4) Cryotherapy
What episcleral tumors typically occur in horses and cattles
Squamous cell carcinoma (SCC) - usually limbal
T/F: episcleral tumors are common in cats
False- rare in cats
What is most common episcleral tumors in dog
1) Epibulbar melanoma - hard to remove, can lead to glaucoma (block drainage angle at limbus)
2) Hemangiosarcoma
What is the biggest risk with older dogs with epibulbar melanoma
to can lead to glaucoma by blocking the drainage angle at the limbus
epibulbar melanoma in young dogs is typically
very aggressive locally to eye and metastasize
typically enucleate the eye
epibulbar melanoma in old dogs is typically
slow to grow and doesn’t metastasize
might block drainage angle at the limbus leading to glaucoma
How many layers are in the cornea
1) Tear film *
2) Epithelium (5-7 layers, water tight, prevents drugs from entering, lipophilic, strong turnover 24 hours period replaced)
3) Stroma (strong collagen later, perfect arrangement)
4) Descemet’s membrane
5) Endothelium
What is the function of the cornea tear fim
-Smooth ocular surface
-oxygen and nutrients
-removes waste
-optical transparency
-immunologic functions
5-7 layers, water tight, prevents drugs from entering, lipophilic, strong turnover 24 hours period replaced
corneal epithelium
layer of cornea:
75% water, 25% collagen
loves fluorescein
relatively acellular
keratocyte primary cell type
takes longer to repair
stroma
What layer of the cornea does fluorescein bind to
Stroma
What is the primary cell type of the stroma
keratocyte
layer of the cornea that dehydrates stroma aqeuous humor by pumping mechanism
non-regenerative
Endothelium
T/F: cornea endothelium is regenerative
False- neighboring cells hypertrophy but eventually cant keep up
What does the cornea not have
-Blood vessels
-Epithelial pigment
-Keratinization
-Lymphoid tissue
precise collagen arrangement
relatively acellular
relatively dehydrated
cornea
What innervates the cornea
CN V (trigeminal) - ophthalmic branch
What dog breeds have decreased innervation compared to others
brachycephalic dogs
why are superficial corneal ulcers very painful
cornea - by CN V (trigeminal)
more nerve endings (unsheathed) in epithelium/superficial cornea so it is very painful
Where is there a higher nerve density in the cornea
at the center superficially
Dolicocephalic > Brachycephalic
Are superficial or deep corneal ulcers more painful
Superficial
any stimulation of corneal nerves =
reflex stimulation of CN V nerve branches to anterior uveal tract
leading to reflex uveitis with painful ciliary body muscle spasm
Reflex uveitis
occurs when cornea is stimulated in all cases of keratitis
stimulation of CN V leads to reflex uveitis with painful ciliary body muscle spasm
more severe keratitis = more severe uveitis
How do you relieve painful ciliary body muscle spasms from reflex uveitis?
Cycoplegic drugs such as atropine
(mydriatic)
How do epithelial wounds heal
stem cells turnover rapidly to fill in defect
doesnt need help from other sources
sound happen in days
How do stromal wounds heals
not just regenerating cells
rebuilding collagen and arranging in different order to become see through again
-complex process that takes a lot of time
Characteristics of corneal epithelial wound healing
1) Epithelial cells lose adheasion to basement membrane
2) Mitosis with increased cell numbers and activation of limbal stem cells
3) Migration of cells until defect close
4) Re-establishment of basement membrane adhesion
very quick- within 24 hours when you arent filling in a defect
happens quickly
minimal fibrosis hence minimal loss of transparency
no treatment currently available to speed epitheliazation
corneal epithelial healing
Characteristic of corneal stromal wound healing
-Happens slowly
-Requires activation, transformation and migration of keratocytes into fibroblasts
-May require vascularization
-fibrosis initially, follwed by new collagen synthesis
-epithelization often precedes resolution of stromal remodeling
How do you treat corneal epithelial wound
no treatment currently available to speed epithelialization
just give it time (5-7 days) and prevent infection
corneal facet
when there is still a divot in the cornea but epithelial cells have covered the healing stroma (which hasn’t caught up to the epithelial cells)
-Does not take up stain
T/F: corneal facets do not take up stain
True
All corneal disease can be simplified to which two pathologic states
1) Loss of transparency
2) Loss of thickness (corneal ulceration)
What layers of the cornea are hydrophilic
stroma- loves fluorescein sodium and bind immediately
What layers of the cornea are hydrophobic
epithelium
descemet’s membrane
How do you diagnose corneal ulcers
Fluorescein sodium binding to the stroma
What are the different kinds of corneal ulcers *
1) Simple: Superficial, Not infected, heal in appropriate amount of time, no complicating factors
2) Complicated: deep (loss of stroma), infected/melting, complicating factors present, slow to heal
What are the 4 criteria of a simple corneal ulcer
1) Superficial - curvature intact
2) Not infected - no cellular infiltrate, no organisms on cytology, negative culture and sensitivity, no concurrent keratomalacia (corneal melting), no stromal loss
3) Heal in appropriate amount of time: 5-7 days
4) No Complicating factors
How do you tell a corneal ulcer isnt superficial
loss of corneal curvature
How do you tell a corneal ulcer isnt infected
-no cellular infiltrate (opacity)
-no organisms on cytology (very important)
-negative culture and sensitivity
-no concurrent keratomalacia (corneal melting)
-no stromal loss
-no other concurrent signs: conjunctival hyperemia, episcleral injection, degree of reflex uveitis, constricted pupil
What is the normal canine cornea healing time
Should be healed in 5-7 days
-epithelial defects alone heal faster than those involving stromal defects
any delay in wound healing = complication
What are complicating factors in corneal ulcers that may contribute to non-healing *
-Entropion
-KCS
-Eyelid tumors
-Lagophthalmos
-Ectopic cilia
-Trigeminal neuropathy
-Systemic disease (ie Cushings, diabetes mellitus)
-Distichiasis
How do you treat superficial ulcers **
You arent making the ulcer heal
1) Broad spectrum topical antibiotic TID
Dog: Triple antibiotic ideal (Neomycin Polymixin B _ Bacitracin/ Gramicidin)
Cat: Erythromycin or Tobramycin
2) Analgesia (3-5 days)
Oral NSAID (never topical) or Gabapentic
Topic Atropine
3) E-collar if necessary to prevent self-trauma
recheck 5-7 days for normal dogs, 203 days for brachycephalic dogs
What would the cytology of an infected ulcer look like
neutrophils, intracellular and extracellular bacteria, fungus, etc
T/F: you should use a topical NSAID to heal a corneal ulcer
False- it delays healing and not analgesia- no prostaglandin receptors in cornea)
use an oral NSAID instead (wont do this)
Why should you never use topical NSAID to heal a corneal ulcer
1) Delays healing
2) Not analgesic: no prostaglandin receptors in cornea
When do you recheck superficial corneal ulcers
Normal dogs 5-7 days
Brachcephalic dogs 2-3 days
Prolonged properacaine is toxic to the
epithelium - not a treatment tool
only a diagnostic tool
will delay corneal healing
Why do you need to recheck brachycephalic breeds with corneal ulcers in 2-3 days while other dogs are 5-7 days?
-Decreased corneal sensation
-Lagophthalmos
-evaporative keratitis (from not blinking)
-Increased incidence of KCS
*More likely to experience complications in corneal healing
incomplete or abnormal closure of the eyelids
Lagophthalmos
with corneal perforations, what fills in the gap
fibrin plug - prevent aqeuous humor from leaking out
Why do cornea’s melt?
bacterial +fungal infections (Pneumonas and Aspergillus)
chew through collagen and
Neutrophil
If corneal stromal loss is >50% of corneal thickness or cornea is perforation, what should you do
refer for surgical grafting procedure (synthetic graft or conjunctival graft)
cases with additional complicating factors likely warrant sooner referral
What is an immediate side effect of synthetic graft or conjunctival graft
blinded that eye with graft material
synthetic graft or conjunctival graft
used for corneal stromal loss that is >50% of corneal thickness or perforated cornea
after months of healing, graft material is trimmed off, might be able to see around eye
How do you rule out a complicated corneal ulcer? *
Cytology is most rapid and economic
1) Topical proparacaine
2) Two slides- one for pathologist or gramstain, one for you
3) Microbrush dental applicator or cytobrish or handle-end of scalpel blade
With complicated ulcers, what are the downsides of culture and sensitivity
they will take 48 hours
Upon cytology of a complicated corneal ulcer you see bacteria, what should you do next
Topical anti-microbial q2-6h (big guns- cidal drugs)
-Ofloxacin (mostly G- but broad fluoroquinolone)
-Cephalexin (G+)
Added together
+/- Voriconazole 0.3% (antifungal)
+/- oral antibiotic, Clavamox
Control any secondary uveitis- topical atropine 1% solution q8-24h and oral NSAIDs
Provide analgesia if painful: oral gabapentin
Ecollar
For complicated ulcers being treated with antimicrobials, how often do you need to give them
q2-6 hours- much more often
Topical 2nd gen fluroquinolone that mainly has gram negative coverage but is a big gun in treatin complicated infected corneal ulcers
Ofloxacin 0.3%
Topical cephalosporin that mainly has gram + coverage, added with other antimicrobials for treated complicated corneal ulcers
Cephalexin
What anti-fungal should you use to add to treat fungal corneal ulcers or added on when treating horses
Voriconazole 0.3% - best corneal penetration
In complicated ulcers, how do you control for secondary uveitis
-Topical atropine 1% solution q8-24h
(Cats- try to use ointment or they will foam at the mouth)
-Oral NSAIDs
What is a good oral antibiotic added with topical antibiotics for complicated infected corneal ulcers in dogs
Clavamox
In complicated corneal ulcers, what should you do for analgesia
oral gabapentin when paired with NSAID
How do you treat corneal malacia *
topical anti-collagenase / anti-protease q1-6h
1) Autologous / heterologous serum
-Red top tube, draw off serum and give to client
2) Tetracycline- oxytetracycline ointment / Doxycycline 5mg/kg PO q12h
3) EDTA solution- fill half of a purple top tube with saline, can dispense in dropper bottle for ease of administration
What are the 4-5A’s of complicated corneal ulcer therapy in dogs and cats *
1) Antibiotic- topical
2) Anti-collagenase/protease -topical (serum/EDTA)
3) Atropine - topical
4) Antibiotic- oral
5) Anti-inflammatory - oral
What are the 4-5 A’s of complicated corneal ulcer therapy in horses *****
1) Antibiotic- topical
2) Anti-fungal- topical
3) Anti-collagenase/protease - topical
4) Atropine - topical
5) Anti-inflammatory
they dont need oral antibiotics but do need topical antifungals
Should you do a tarsorrhaphy for complicated ulcer with stromal loss?
No - you cant track the progress
How do you administer eye medication into the horse *
Subpalpebral lavage tube
Subpalpebral lavage tube
used in cases of corneal damage, stromal abscess
allows you to put in solutions frequently of anti-fungal and antimicrobials
DO not push air into the tube
are aminoglycosides cidal or static
cidal but not good spectrum of activity
used as little guns
-Gentamycin
-Tobramycin
Gentamicin and Tobramycin are ______
fluoroquinolones (cidal) but not good spectrum
little guns
What is a common topical cephalopsporin used as good gram + coverage
Cefazolin
What is one downside in using topical cephalosporings
they dont penetrate an intact epithelium
What are different fluoroquinoloes used to treat ulcerative corneal disease
Ciprofloxacin (very painful)
Ofloxacin
Moxifloxacin
With any type of ulcer, what should you absolutely not give
1) Steroids
2) NO topical NSAIDs
prevent
-epithelial healing
-leukocyte migration
-collagen formation
-corneal vascularization
Increase effects of collagenases
Suppresses immune system
For corneal ulcers, why should you not give steroids or topical NSAIDs
they prevent
-epithelial healing
-leukocyte migration
-collagen formation
-corneal vascularization
Increase effects of collagenases
Suppresses immune system
you have a young dog with recurrent ulceration in the dorsal central cornea, what might be happening
ectopic cilia
What are canine indolent corneal ulcers *
Superficial, loose, non-adherent epithelial flaps (looks like you can w
non healing superficial ulcers that are present for weeks to months
No evidence of infection
Careful exam and rule out other causes (entropion, ectopic cilia, etc)
What systemic diseases might cause healing corneal ulcers
Cushings (esp horses)
Diabetes
What is the pathogenesis of indolent ulcers *
Failure of normal cell-cell adhesion between the epithelium and its basement membrane and underlying stroma
How do you treat indolent ulcers *
grid keratomy or diamond burr debridement
opens up the new stroma that promotes healthy cell to cell adhesion complex formation
Grid Keratomy and Diamond Burr debridement is for
Treatment of indolent ulcers
opens up the new stroma that promotes healthy cell to cell adhesion complex formation
Never for complicated ulcers or cats
You should never do Keratomy and Diamond Burr debridement if
1) Complicated ulcers: infection, melting, stromal losses - will just drive the infection deeper down (do cytology to rule out infection first)
2) Cats - most common cause of indolent ulcers if FHV-1
How do you prepare for Keratomy and Diamond Burr debridement
good restraint
topical anesthesia (proparacaine)
dilute betadine rinse to clean corneal surface
cotton tip applicators- do not have to be sterile
25g needed
dry q-tips
Cotton tip: debride all loose epthelium with dry cotton tip applicator - move 360 limbus to limbus all the way around
Grid keratotomy: superficial lines across ulcer bed. 1mm of healthy cornea on either side of ulcer bed
Diamond burr debridement: rotating 3.5mm burr, creates fine abrasions in anterior stroma similar to grid keratomy
very safe and easy to perform
placement of bandage contact lens
rotating 3.5mm burr, creates fine abrasions in anterior stroma similar to grid keratomy
very safe and easy to perform
then place bandage contact lens
treatment for indolent ulcers
diamond burr debridement
superficial lines across ulcer bed. 1mm of healthy cornea on either side of ulcer bed
treatment for indolent ulcers
grid keratomy
After doing Keratomy and Diamond Burr debridement, what should be done afterwards
-Ecollar
-Atropine 1% solution q24h for reflex uveitis
-Broad spectrium antibiotics- Terramycin or tetracyclines
-Analgesia: Oral NSAID for 5-7 days and oral gabapentin for 3-5 days
What is the most common cause of corneal ulcers in cats *
Feline herpesvirus -1
What is classic sign of FHV-1
dendritic ulcers
How do you treat FHV-1 *
1) Topical antiviral:
Cidofovir 0.5% solution BID x 2-3weeks *
Idoxuridine
Trifluridine
2) Systemic antiviral therapy (if URT)
Famciclovir 40mg/kg PO TID
3) L-lysine
4) Minimize stress
What systemic anti-viral is fatal to cats
Acyclovir
What does a white cornea indicate
1) Corneal dystrophy
2) Corneal degeneration
3) Fibrosis
4) Descemet’s striae
5) Keratic precipitates
white corneal opacity
bilateral
purebreds
non-painful
non-progressive
needs no treatment
does not interfere with vision
Metabolic deposits of lipid or calcium
Corneal Dystrophy
white corneal opacity
unilateral or bilateral
usually asymmetric
associated with concurrent ocular surface or intraocular disease
systemic implications: hypoT4, hyperlipidemia
vascularization frequent finding
often associated with ulceration of overlying epithelium
most commonly calcium deposits
Corneal degeneration
what is a frequent finding of corneal degeneration
vascularization
What causes corneal degeneration
associated with concurrent ocular surface or intraocular disease
systemic implications: hypoT4, hyperlipidemia
vascularization frequent finding
often associated with ulceration of overlying epithelium
most commonly calcium deposits
How do you treat corneal degeneration
1) Identify any concurrent ocular or systemic diseases and treat (ie KCS, HypoT4, hyperlipidemia)
2) Will typically scrap calcium out
3) EDTA helps
Strongly consider referral (or at least send some photos to your favorite ophthalmologist and discuss case)
fair to guarded prognosis based on stability of epithelium
white corneal opacity for disorganized collagen
associated with previous corneal ulcer/keratitis
may also be associated with vascularization and pigmentation
Non painful (follows healing of corneal disease)
variable effect on vision depending on size
does not need treatment
Corneal fibrosis
Is corneal fibrosis painful?
No
Do you treat corneal fibrosis?
No
What might be causing a brown corneal opacity
1) pigement
2) neoplasia (melanoma)
3) sequestrum
4) iris prolapse
5) foreign body
6) dermoid
What might be causing a yellow corneal opacity
stromal infiltrate / WBCs
What does a blue corneal opacity mean *
Edema
-epithelium is a natural barrier to edema
-endothelium barrier and active pump
Focal edema = epithelial disease
generalized edema = endothelial disease
focal corneal edema means there is an ________ *
epithelial disease
generalized corneal edema means there is an _______ *
endothelial disease
pumps degenerate and cant pump out
what disease in dogs can cause bilateral cornea edema
distemper
What are your differentials for focal cornea edema *
1) Ulcerative keratitis- corneal laceration or perforation
2) Non-ulcerative keratitis
3) Keratic precipitates
4) Anterior lens luxation
What are your differentials for diffuse cornea edema
1) Glaucoma
2) Anterior uveitis
3) Endophthalmitis
4) Endothelial dystrophy
5) Senile endothelial degeneration
6) Immune memdiated endothelitis
7) Blue-eye (CAV) -rare
What breeds get endothelial dystrophy leading to diffuse corneal edema
Boston terriers
Dachshund
Chihuahuas
Basset hounds
Endothelial dystrophy
diffuse corneal edema due to loss of endothelium leading to vision loss
common in
Boston terriers
Dachshund
Chihuahuas
Basset hounds
How do you treat corneal edema *
depends on cause
tx primary cause (ulcerative keratitis, non-ulcerative keratitis, keratic precipitates, anterior lens luxation, glaucoma, anterior uveitis, endophthalmitis)
1) Topic hyperosmotics - 5% saline (ointment more efficacious than solution)
TID to QID
2) Thermokeratoplasty: burn marks into stroma- edema is lost
What causes red corneal opacities *
blood vessels
almost all red corneal opacities are
vascularization of the cornea
Vascularization of the cornea is a
common and non-sepcific response to variety of insults
corneal vascularization with corneal ulcers
simple ulcers are not generally associated with vascularization
ulcers involving stromal loss frequently heal by vascularizations
With corneal ulcers when do you see corneal vascularization
ulcers involving stromal loss frequently heal by vascularizations
T/F: indolent ulcers have variable vascularization
true - more chronic = more vessels
Where do the corneal blood vessels come from
superficial: conjunctiva (cross limbus)
deep: uveal tract: wont see them cross limbus
What do superficial corneal vessels look like *
branch like trees/ hedge (typically 360 degrees around)
What do deep corneal vessels look like
dense like hedge
show there is deep corneal or intraocular disease present
What diseases are associated with superficial corneal vascularization
KCS/Dry eye
diagnose via schirmer tear test
corneal transparency may imrpove with treatment
all red eyes and all eyes with discharge need a STT
What is another name for pannus
Chronic Superficial Keratitis (CSK)
What causes Chronic Superficial Keratitis (CSK)
or pannus *
immune mediated (lymphoplasmacytic) corneal disease of german shephards, shepherd mixes and sighthoud mixes
non-painful, progressive, exacerbated by exposure to UV light
What breeds get Pannus or Chronic Superficial Keratitis (CSK)
German Shepherds
Shepherd mixes
sighhound mixes
What are the clinical signs of Chronic Superficial Keratitis (CSK)
-Superficial vascularization
-Pigmentation
-Corneal degeneration
-Fibrosis
what type of inflammation is seen with Chronic Superficial Keratitis (CSK)
lymphocytic plasmocytic inflammation
Where does Chronic Superficial Keratitis (CSK) typically begin
temporal limbus can progress to blindness
is Chronic Superficial Keratitis (CSK) unilateral or bilateral
bilateral but not always symmetric
How do you treat Chronic Superficial Keratitis (CSK) “pannus” *
1) Topical dexamethasone 0.1% or topical 1% prednisolone acetate solution BID to QID
-Initial tx until CsA or Tacro start working
2) Topical cyclosporin A 0.2% ointment or tacrolimus (better for pigment)
-take 6-8 weeks to reach therapeutic levels in the cornea
3) Goggles to decrease exposure to UV light
Recheck in 2 months and slow taper of medications once disease is controlled
Treatment is lifelong- disease is. controlled not cured
In treating Chronic Superficial Keratitis (CSK), is cyclosporin or tacrolimus better for getting rid of pigment
Tacrolimus
thickening of the third eyelid associated with immune mediated inflammation
Plasmoma (atypical pannus)
What diseases are associated with corneal vascularization
1) Ulcerative keratitis/ lacerations/ performations
2) KCS
3) Intraocular disease (uveitis, glaucoma)
4) Pannus / CSK
5) Episclerokeratitis/ nodular episcleritis / nodular fasciitis
6) Neoplasia
7) Eosinophilic keratitis
What breed gets pigmentary keratopathy *
pugs - likely genetic disease
80% of pugs are affected to some degree
treatment: prevent pigment from covering entire cornea or it can lead to blindless
Pigmentary keratopathy in the pug is typically bialteral or unilateral
bilateral - not always symmetrical but starts with the medial pigment
How does Pigmentary keratopathy in the pug progress *
starts medially and progresses laterally often lateral
often has superficial vascularization associated with areas of pigmentation
How do you medically manage Pigmentary keratopathy in the pug *
-Treat any associated KCS
-Immunomodulation
Cyclosproing A and Tacrolimus (better for pigment)
-Topical steroids may help but are dangerous in at-risk brachycephalic corneas
-Lubricants may help with exposure keratopathy and protect cornea from any associated entropion
Treatment will be lifelong
necrotic corneal stroma giving brown corneal opacity in cats
feline sequestrum
tx: surgical resection
Limbal melanoma is more aggressive in __________ and slower progression in ________
aggressive: young dogs
slower: older dogs
How might cats get feline corneal sequestrum
brachycephalic cats predisposed
chronic ocular irritation (tear film abnormalities, entropion, FHV-1)
How do you treat feline corneal sequestrum
if <50% remove lesion
if >50% grafting procedure
-conjunctival graft
-slding corneal-conjunctival transposition
Pannus and Pigmentary keratopathy in the pug are
life long treatments
