'D-shaped' and 'reverse-D-shaped' pupil in a cat with lymphosarcoma

A 7-year-old female spayed European shorthair cat was presented because of visual reduction and a green reflex in the right eye. Examination revealed a 'D-shaped' pupil in the right eye and a 'reverse-D-shaped' pupil in the left eye. Both eyes showed fibrinous anterior uveitis with exudates in the anterior chamber and precipitates on the posterior surface of the cornea. In both eyes a chorioretinitis was diagnosed which caused partial retinal detachment and peripapillary oedema in the left eye. Histopathology revealed intestinal and ocular lymphosarcoma. The aberrant pupil shapes which persisted after death were due to infiltration of the iris stroma and were not caused neurologically. The observation that in both eyes only the medial parts of the iris were affected could not be explained.