Retrobulbar pseudotumor of the orbit in a cat.

Idiopathic nonspecific inflammatory disease of the orbit (orbital pseudotumor) was diagnosed detected in a cat. The cat had progressive lagophthalmia, keratitis, and decreased motion of the right eye. Four months later, the left eye was affected in a similar manner. Response to antibiotics and immunosuppressive agents was not detected. Computed tomography of the brain and orbits revealed bilateral thickening of the sclera and episcleral tissues. Bilateral exenteration of the eyes was required because of worsening clinical signs or corneal perforation. Histologic examination revealed proliferation of spindle cells and fibrovascular tissue within and adjacent to the sclera.