Gelding, discharge from right eye 

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Morphologic diagnosis?

3rd eyelid and palpebra: squamous cell carcinoma

Lab, Unilateral enucleation

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Morphological diagnosis?

Intraocular (uveal) melanoma

Equine recurring uveitis, with pus running from both eyes

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Morphologic Diagnosis?

Pathogenesis?

Morphologic Diagnosis: Chronic diffuse fibrinous endopthalmitis with posterior synechiae and corneal neovascularization

Pathogenesis: The horse was infected with Leptospira --> horse mounted an immune response (T and B cell) against Leptospira antigens --> these cells and antibodies cros-reaction with antigens in the uvea --> lymphoplasmacytic uveitis; there are recurrent bouts of acute inflammation with intermittent quiescent periods

Jersey Bull, euthanized for unrelated reasons

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Morphologic Diagnosis?

How would this heal?

Morphologic Diagnosis: Acute focal corneal ulcer; acute diffuse hyphema; Acute multifocal subretinal hemorrage with retinal detachment

Healing: Flattening and sliding of epithelium to cover the defect, then mitosis of epithelial cells to replace lost ones. The deeper part of the ulcer will fill with fibrous tissue

Lab, underwent unilateral enucleation of eye for exophthalmos

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Morphologic Diagnosis?

Other Differential Diagnosis?

Morphologic Diagnosis: Retrobulbar meningioma

Differential Diagnosis: Retrobulbar Lymphoma

Newborn crossbred male calf with arthrogryposis of all four limbs

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Morphologic Diagnosis?

Causes?

Morphologic Diagnosis:Eye, left side: Micropthalmia and internal hydrocephalus

Possible Causes: In utero viral infection with bovine viral diarrhea virus, or vitamin A deficiency, inherited genetic defects

Corneal ulcer that is stained with flurecein, this reveals the extent of the ulcer

Corneal Edema

The hazy blue discoloration is due to imbibition of fluid of fluid with in the corneal stroma.

Suppurative keratomalacia "melting ulcer." This is a corneal ulcer with suppurative exudate due to secondary infection with Pseudomonas sp.

Steer with descemetocele: This is a corneal ulcer that has progressed down to Descemet's membrane. The center of the ulcer is clear and bulges slightly enteriorly because only the membrane is still intact.

Cross-section of eye with a corneal ulcer. The iris has a prolapsed into perforation, forming a plug; this is a staphyloma.

Corneal epidermalization. The stratified squamous epithelium of the cornea has proliferated, developed rete pegs, and is somewhat keratinized similar to the epidermis; this is a response to chronic injury.

Corneal neovascularization. New vessels have grown into the corneal stroma toward a healing ulcer.

Chronic bilateral keratitis.

Chronic injury to the superficial cornea has resulted in fibrosis, epithelial hyperplasia and neovascularization of both corneas.

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Morphologic Diagnosis?

Chronic Keratitis in cat.

The brown discolored area is a corneal sequestrum. The inset in the upper left shows the microscopic appearance of the brown discolored sequestrum.

What is goniodygenesis?

What might it contribute to?

* Incomplete or dysplastic development of iridocorneal angle, pectinate ligament, ciliary cleft

*May contribute to glaucoma

Goniodysgenesis in a cocker spaniel with primary glaucoma

Acute uveitis with hypopyon

(purulent exudate in the anterior chamber)

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Morphological Diagnosis?

Retrobulbular cellulitis with ulcerative keratinitis and acute serofibrinous anterior uveitis

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Condition?

Lymphoplasmacytic anterior uveitis.

Common idiopathic condition in dog, here it has resulted from closure of the cilliary cleft

Lymphoplasmacytic/ pyogranunlamatous uveitis associated with lens rupture

Reaction to injury:

Preiridial Fibrovascular Membrane 

(PIFM, Rubeosis Iridis)

What does this result in?

Proliferation of fibrovascular tissue on the anterior surface of iris

May result in:

-Anterior synechia: adhesion of iris to cornea

-Posterior synechia: adhesion of iris to lens capsule

-Closure of iridocorneal angle: -> secondary to glaucoma

-Entropion uveae: inward contraction o pupillary margin

-Ectropion uveae: outward contraction of pupillary margin

Reaction to injry:

Intra-ocular hemorrhage

Where is this at?

What can it cause?

Location: only in vessels in globe in the uvea or retina

May cause: trauma, inflammation, hypertensive vasculopathy, neoplasms, and detached retina

Reactions to Injury:

Neoplasms

What type?

Where are they located?

Melanoma: anterior uvea

Cilliary body epithelial tumors

Lymphosarcoma: anterior uvea and choriod

Anterior Synechia

The iris is displaced anteriorly and is adherent to the cornea also note the neovascularization in the cornea and the accumulation of serofibrinous exudate in the posterior chamber

Preiridial fibrovascular membrane (PIFM)

on the anterior surface of the iris (arrows

Iris Bombe

This is formed by a 360 degree posterior synechia, which results in obstruction of aqueous humor flow into the anterior chamber. The increase in pressure in the posterior chamber causes the iris to bulg anteriorly (arrow)