To compare the changes in macular thickeness between non-diabetic group and a mild or moderate nonproliferative diabetic retinopathy group after phacoemulsification.

This study consisted of 32 eyes of 22 patients who underwent phacoemulsification. The non-diabetic group included 20 eyes of 15 patients; the diabetic group (mild or moderate nonproliferative diabetic retinopathy) included 12 eyes of 7 patients. Macular thickness using optical coherence tomography (OCT) and corrected visual acuity were measured before surgery and 1 day, 1 week, 1 month, 2 months, 6 months and 12 months after surgery.

In the non-diabetic group, the macular thickness increased by 2.8±4.2% at 1 week, 5.9±4.5% at 1 month, 4.8±3.8% at 2 months, 0.6±0.8% at 6 months, and -0.3±1.2% at 12 months after surgery, while it increased by 4.8±5.0% at 1 week, 11.1±5.2% at one month, 9.9±6.0% at two months, 8.1±4.6% at 6 months, 3.9±3.5% at 12 months in the diabetic group. The increased amount of macular thickness was significantly higher in the diabetic group than in the non-diabetic group at 1 month, 2 months, 6 months, and 12 months. Visual acuity was not significantly different between the diabetic and non-diabetic groups. In the non-diabetic group, 2 months after the operation, LogMAR below 0.02 (Snellen 0.95) were remained with best corrected visual acuity. Similarly to non-diabetic patients, diabetic patients needed 12 months to reach best corrected visual acuity.

Macular thickness increased in both diabetic and non-diabetic groups after phacoemulsification, and the increased amount of macular thickness was significantly greater and lasted longer in the diabetic group compared with the non-diabetic group. In cases of mild or moderate nonproliferative diabetic retinopathy, macular thickness change due to cataract surgery did not influence visual acuity.