The feline glaucomas: 82 cases (1995-1999)

To describe signalment, ophthalmic abnormalities, and response to treatment in cats with glaucoma.

Retrospective study.

Eighty-two cats with 93 glaucomatous eyes. CRITERIA FOR INCLUSION: Medical records of all cats with glaucoma presented to the ophthalmology services at two referral specialty hospitals between 1995 and 1999 were reviewed. Cats were included if intraocular pressure (IOP) > 25 mmHg, if buphthalmos was present, or if a shallow anterior chamber was present and IOP > or = 5 mm Hg higher than the contralateral normal eye.

Mean +/- SD age was 9.2 +/- 4.4 years. Thirty-one cats were female; 51 were male. Breeds included 69 domestic and 13 pure-bred cats. One eye was affected in 71 cats; both eyes in 11 cats. The most common presenting complaints and ophthalmic abnormalities were cataract, corneal edema, mydriasis, buphthalmos, cloudy eye, and blindness. Mean intraocular pressure in the affected eye was 36.4 +/- 14.7 mmHg. The glaucomas were believed to be secondary in 81 eyes, primary in five eyes, and undetermined in seven eyes. The goal of medical therapy was to maintain IOP in a comfortable range we presumed to be < 30 mm Hg in blind eyes, and to maintain IOP below 25 mmHg to preserve vision in visual eyes. Intraocular pressure was maintained in a comfortable range or normal range in 58% of all eyes using medical therapy alone. Surgery was performed in nine eyes after medical management failed. Sixty-seven eyes were blind, 21 were visual, and five had decreased vision at initial presentation. With treatment, vision was retained in nine eyes, deteriorated in five eyes, and was lost in three eyes.

The glaucomas were most frequently secondary in cats and resulted in blindness prior to presentation in the majority of eyes in our study. Medical management controlled IOP in more than half of the eyes, and maintained vision in almost half of visual eyes.