Retrospective analysis of ocular neuropathies in diabetic dogs following cataract surgery.

Abstract

To describe and compare the cumulative incidence and clinical progression of ocular neuropathies in diabetic dogs vs nondiabetic dogs following cataract surgery. Medical records of 196 diabetic and 442 nondiabetic dogs who underwent cataract surgery between 2004 and 2015 were reviewed. The percentage of patients affected by neuropathy and potential risk factors were compared between groups. Patients with diabetes mellitus (DM) were 20.4 times more likely to develop an ocular neuropathy than patients without DM (12.24% vs 0.68%). Twenty-four diabetic patients were affected by mononeuropathies or polyneuropathies including Horner's syndrome (n=20), facial neuropathy (n=5), and neurogenic keratoconjunctivitis sicca (NKCS) (n=5). The odds of a diabetic patient developing Horner's syndrome and NKCS were 86.3 and 20.7 times higher than a nondiabetic patient, respectively. The average duration of DM prior to diagnosis of neuropathy was 659days (range 110-2390days; median 559days). Complete resolution was achieved in 10 of 22 neuropathies (45%) within an average of 248days (range 21-638days; median 187days) after diagnosis. The odds of developing an ocular neuropathy, specifically Horner's syndrome and NKCS, are statistically higher in diabetic patients compared to nondiabetic patients. Neuropathies were observed as a long-term complication in this group of diabetic patients, and complete resolution of the neuropathy was observed in less than half of the affected population.