Incidence of nonarteritic ischemic optic neuropathy following topical clear corneal cataract surgery: survey and meta-analysis

ABSTRACT Objective We estimate the incidence and characteristics of post-cataract-surgery nonarteritic ischemic optic neuropathy (PCNAION) after topical clear corneal cataract extraction (CCCE) in Canada. Design Canada-wide internet survey and meta-analysis Participants All certified Canadian ophthalmologists in the Canadian Ophthalmological Society directory, or belonging to a provincial ophthalmology internet group. Methods Identical surveys were distributed to 5 regions in Canada. CCCE surgeons were asked to estimate the number of CCCE they had performed in their career, and the number of PCNAION events that occurred within 1 year after CCCE. The results were analyzed using a random effects meta-analysis of proportions for rare events. Results The estimated survey response rate was 18%–32%. The 182 survey respondents performed a total of 1 499 694 CCCE with 107 events of PCNAION. Twenty-six percent of surgeons had at least one patient with PCNAION. Meta-analysis revealed a pooled estimate incidence of 2.8 PCNAION events (95% confidence interval 1.6–4.7) per 100 000 cataract procedures during the year after cataract surgery. Seventy-seven percent (82/107) of the PCNAION cases occurred within 3 weeks of surgery, and 7 patients had bilateral PCNAION. Conclusions PCNAION is a rare complication after topical CCCE. Its incidence is important to estimate for patient care and epidemiologic reasons.