AIM: To examine the micrangium through optical coherence tomography(OCT)in diabetic patients and to quantify the thickness of macular retia at different timing.

METHODS: Control group(Group A)had 40 patients with 59 eyes, who were all diagnosed as cataract but no diabetes history. Experiment group(Group B)had 49 patients with 52 eyes, and patients were all diagnosed as Type 2 diabetes for over 2a with cataract. All patients were examined using OCT before and after operation, including regular eye examinations. At 1d, 1wk and 1mo after operations, those data were examined again, except OCT.

RESULTS: Compare to patients both had cataract and diabetes, cataract patients showed a better visual acuity after operation(χ²=8.38,P=0.004). Thickness of central fovea of macula: for patients both had cataract and diabetes, their central fovea of macula thickened significantly in 1wk after operation. However, for patients only had cataract, thickness of their central fovea of macula did not increase until 1mo after operation. Thickness of strata neuro- epithelium at central fovea of macula area: for patients both had cataract and diabetes, their strata neuro- epithelium thickened in 1d after operation. However, for patients only with cataract, it did not happen until 1mo. Thickness of pigmentary epithelium at central fovea of macula area: for patients both had cataract and diabetes, their pigmentary epithelium thickened in 1wk after operation. However, for patients only with cataract, it was not until 1mo.

CONCLUSION: Patients with cataract and diabetes are more likely to develop macular hydroncus after operation, and it is more serious than patients with cataract alone. Blood-retinal barrier damage is the major cause for retinal damage after phacoemulsification. Corrected visual acuity is along with the thickness of pigmentary epithelium at central fovea of macula area.