Five cases of pigmented paravenous retinochoroidal atrophy in dogs.

OBJECTIVE

To describe a funduscopic finding in dogs that is referred to as Pigmented Paravenous Retinochoroidal Atrophy (PPRCA).

ANIMALS STUDIED: Over a period of 24 years of ophthalmological practice, five cases of a characteristic paravenous retinal atrophy were observed in dogs.

PROCEDURES: A comprehensive clinical ophthalmological examination in all five dogs was complemented by abdominal sonography (cases 1, 3), clinical pathology analysis (cases 1, 3, 4), and a histological examination of both bulbi, kidneys, spleen, and liver in one dog (case 1).

RESULTS

Localized hyper-reflectivity in the tapetal fundus was observed in all five dogs and demonstrated a characteristic perivascular distribution along some peripheral retinal blood vessels. In these areas, geographic copper-brown coloration that tended to become darker with time was seen. Ophthalmoscopic signs of inflammation were lacking. The funduscopic abnormalities slowly progressed in size over years. Visual impairment could not be detected. Histopathology in one dog revealed severe retinal atrophy with multifocal perivascular distribution, mainly affecting the tapetal fundus and occasionally expanding into the nontapetal fundus.

CONCLUSIONS

The described retinal lesions bear similarities with PPRCA in humans. As in humans, it appears to be an incidental funduscopic finding that is not associated with obvious vision impairment.