Radial Artery Pseudoaneurysm in a Maine Coon Cat.

Objective: To report the diagnosis and treatment of a radial artery pseudoaneurysm in a cat. Study Design: Clinical report. Animal: Maine Coon cat (8-year-old neutered male). Methods: Ultrasonographic and angiographic examination of a fluctuant, nonpainful, 3 cm × 1.5 cm subcutaneous swelling on the craniomedial distal aspect of the right radius that occurred 40 days after suspected cat bite trauma was consistent with a radial artery pseudoaneurysm. After ligation of the radial artery proximal to the lesion, the pseudoaneurysm was surgically excised. Results: The excised tissue had hemorrhage and fibrin surrounded by a thick fibrous granulating capsule of variably mature fibroblasts and focal areas of inflammatory cells (lymphocytes, plasma cells, and macrophages) consistent with a pseudoaneurysm. Surgical excision resulted in resolution of clinical signs. Conclusions: Ultrasonography enabled prompt, noninvasive diagnosis of pseudoaneurysm. Angiography or computed tomography may be useful to aid diagnosis and assess the collateral blood supply to the manus before surgical treatment.