The objective of this retrospective case series is to describe the clinicopathological features of feline neoplasia involving the retrobulbar space.

Medical records of 31 cats diagnosed between 2007 and 2019 with neoplasia involving the retrobulbar space were reviewed. Signalment, reason for referral, physical and ophthalmological examination, imaging and pathological findings were recorded. The most common breed was a domestic short hair (21). Median age was 11 years (range: 2–18).

Twenty-one cats were referred for ocular-related problems; 10 cats presented for non-ocular clinical signs only, most frequently respiratory signs (nasal discharge, sneezing and dyspnoea), facial swelling/mass or anorexia.

The most common ocular findings included exophthalmos (16), serous ocular discharge (13), decreased retropulsion (13), third eyelid prolapse (12), periorbital swelling (6), anterior and/or posterior uveitis with associated decrease in vision (2). Cats with exophthalmos exhibited exposure keratitis and corneal ulcerations (6) with one cat presenting with a corneal perforation.

All cats underwent advanced imaging of the head including 3 MRI and 28 CT exams. In 4/31 cats, primary retrobulbar tumours were documented and in the remaining cases tumours with secondary retrobulbar extension were identified.

The diagnosis was achieved via cytology, histopathology or both in 11, 14 and 6 cases, respectively. Tumour types included lymphoma (19), carcinoma (7), sarcoma (3), extramedullary plasma cell tumour (1) and undifferentiated neoplasia (1).

In this study, secondary neoplastic local involvement of the retrobulbar space was most common, with intranasal neoplasia being the most common cause. Lymphoma was identified as the most frequent neoplasia involving the retrobulbar space in cats.

Disclosures

No disclosures to report.