Objective To evaluate the incidence and risk factors associated with development of postoperative glaucoma in the Labrador Retriever following routine phacoemulsification.
Methods Medical records from Labradors and a randomly selected population of non-Labradors were retrospectively evaluated. Signalment, diabetic status, cataract stage, gonioscopic findings, presence of preoperative lens-induced uveitis, development of postoperative hypertension (POH), postoperative glaucoma and postoperative visual status were recorded for each patient. Survival curves were developed using the Cox proportional hazards model.
Results Forty-two Labradors (66 eyes) and 199 non-Labradors (314 eyes) were included. The incidence of POH was significantly higher in Labradors (33%) than non-Labradors (18%). Labradors were at significantly increased risk of postoperative glaucoma and blindness compared to non-Labradors. Estimated probabilities of postoperative glaucoma in Labradors were 23%, 25%, 30% and 35% at weeks 4, 26, 52 and 104, respectively, compared with 5%, 6%, 7% and 9% at weeks 4, 26, 52 and 104, respectively, in non-Labradors. Estimated probabilities of postoperative blindness in Labradors were 5%, 9%, 15% and 27% at weeks 4, 26, 52 and 104, respectively, compared with 2%, 3%, 5% and 10% at weeks 4, 26, 52 and 104, respectively, in non-Labradors. Risk factors for the development of glaucoma in Labradors included increasing age and development of POH. No statistically significant risk factors for the development of glaucoma were identified in non-Labradors.
Conclusions Labradors are at increased risk of glaucoma and blindness following phacoemulsification compared with non-Labradors. POH and increasing age represent risk factors for the development of postoperative glaucoma in Labradors.