Microscopic lesions of spontaneous ocular blastomycosis in dogs.

Ocular tissues from 13 dogs with naturally-occurring blastomycosis were examined histologically. Choroiditis and separation of the sensory retina from its epithelium were the most prominent lesions, although all three coats of the eye were always involved. Severe panophthalmitis was associated with a marked exudative reaction within the ocular tissues. Whereas inflammation of the anterior ocular tissues was often intense, it was rarely associated with the presence of B. dermatitidis. Sequelae to the ocular inflammation included cataract, synechiae, rubeosis iridis, and closure of the drainage angle. The last of these resulted in glaucoma and resulting degeneration of the optic nerve.