PurposeTo determine visual acuity and rates of post-operative cystoid macular oedema (CMO) in an ethnically diverse and predominantly diabetic population.MethodsThe study was undertaken over a one year period. Snellen visual acuity (VA) was measured pre and 4-8 weeks post-operatively and optical coherence topography (OCT) was performed at baseline and post-operatively. No eyes received prophylactic non-steroidal anti-inflammatory drugs (NSAIDs) prior to or after surgery.ResultsOut of 262 eyes, 59% were in the Black, Asian and minority ethnic group (BAME), 57% had a history of diabetes mellitus and 34% had pre-existing diabetic retinopathy. 76% of all eyes achieved 6/12 post-operative VA at the first postoperative review and the incidence of post-operative CMO within the study population was 7.6%. In patients with a history of diabetes mellitus the incidence of post-operative CMO was 10.7% compared to 3.5% in those without diabetes. This was found to be clinically significant (P=0.0297).ConclusionWe believe this is the first study to benchmark standards for care in this demographic of patients. A history of diabetes mellitus, irrespective of whether there is diabetic retinopathy or not, is an independent risk factor for the development of post-operative CMO in patients undergoing cataract surgery (P=0.0297). Ethnicity is not an independent risk factor for the development of post-operative CMO.