Scleral rupture in dogs, cats, and horses

OBJECTIVES: The aim of this retrospective study was to summarize the most frequent clinical signs, ultrasonographic, and histological findings accompanying scleral rupture as a result of blunt trauma in dogs, cats, and horses. ANIMALS STUDIED AND PROCEDURES: Thirty small animals and three horses diagnosed with scleral rupture resulting from blunt trauma. B-mode ultrasonography was performed on 20 animals. Histopathology was carried out on 18 enucleated globes. RESULTS: In small animals, 80% presented hyphema, 60% subconjunctival hemorrhage, and 53% eyelid and conjunctival swelling. In horses, 100% presented eyelid and conjunctival swelling, 67% hyphema, subconjunctival hemorrhage, and collapsed anterior chamber. Ultrasonographic findings were an area with ill-defined scleral margins (90%), echoic/hyperechoic contents in the anterior and posterior chamber (55%) and in the vitreous (80%). In small animals, scleral rupture location noted on gross examination was: at the posterior pole (4), close to the optic nerve (3), near the limbus (2), and in the dorsal aspect of the globe (1). In horses, the lesion was located at the limbus (3). In small animals, histopathology showed presence of hemorrhage in the anterior, posterior chamber, and vitreous (94%), retinal detachment (94%), choroidal edema and hemorrhages (88%), and choroidal detachment as a result of suprachoroidal hemorrhage (88%). The same lesions were found in the globes of two horses. In small animals, rupture location noted on histopathology was: at the posterior pole (8), close to the optic nerve (4), near the limbus (1), near the ciliary body (1). CONCLUSIONS: The most frequent clinical signs observed were hyphema, subconjunctival hemorrhage, and eyelid and conjunctival swelling. Ultrasonographic findings suggestive for scleral rupture were ill-defined scleral borders and/or echoic/hyperechoic material in the cavities of the globe. On histopathology, lesions severely altering the anatomy of the eye structures were: hemorrhage into the chambers of the globe, subretinal and suprachoroidal hemorrhage leading to retinal and choroidal detachment, respectively. In small animals, the most frequent locations for scleral rupture were the posterior pole and close to the optic nerve, whereas in horses it was the limbus.