Clinical, advanced imaging data and outcome of inflammatory and neoplastic orbital disease in 81 dogs and 16 cats in Australia (2010–2019)

Abstract

Objective: To characterize the clinical presentation, advanced imaging features, and outcome of orbital disease in a referral population of dogs and cats that underwent computed tomography (CT) or magnetic resonance imaging (MRI).Animals studied: Client-owned animals.Procedures: Animals referred for orbital disease undergoing ophthalmic examination and either head MRI or CT were included. Demographic and imaging features were compared between animals diagnosed with inflammatory disease and neoplastic disease using Mann-Whitney U and Fischer's exact tests.Results: Ninety-seven animals (81 dogs and 16 cats) were included. Eighty-four and 13 patients underwent CT and MRI scanning, respectively. Inflammatory orbital disease was more frequently detected than neoplasia in dogs (59% vs. 41%) and cats (62% vs. 39%). Orbital cellulitis was the most common diagnosis in dogs (36/81, 44.4%) and cats (8/16, 80%). A foreign body was suspected in 36.1% of dogs with orbital cellulitis but only 3 were retrieved during orbitotomy. Multi-drug resistant bacteria were identified in 3 samples and influenced treatment plans. The most common neoplasms were sarcoma (10/30) and carcinoma (7/30) in dogs and lymphoma in cats (3/6). Imaging findings of osteolysis (p = 0.0002) and intracranial extension (p = 0.0001) were significantly associated with neoplasia in dogs. In contrast, osteolysis extension was present in cats with both inflammatory (7/10) and neoplastic (6/6) orbital disease.Conclusions: Inflammatory disease, particularly orbital cellulitis, was more common than neoplasia in dogs and cats with orbital disease in our population.We recommend including bacterial culture and susceptibility as part of the diagnostic work up when orbital cellulitis is suspected.