Changes Of Choroidal Thickness And Visual Acuity In Diabetic Retinopathy

Purpose:To probe the change of macular choroidal thickness(MCT)in diabetic retinopathy(DR)by using enhanced depth imaging optical coherence tomography(EDI-OCT).Methods:A retrospective research was conducted among 136 eyes(71 patients).Patients' mean age was 57.34±9.42 years.67 eyes were suffered from DR without macular edema(ME),69 eyes with ME and age matched 64 healthy eyes were as control.The choriocapillaris and the medium vascular layers(Sattler's layer)were defined as the choroidal inner layer,and the large vessel layer(Haller's layer)was defined as the choroidal outer layer.Results:All participants underwent binocular EDI-OCT examination.The MCT was 229.50±14.15?m,201.11±14.70?m and 282.31±16.16?m for DR without ME,DR with ME and control,respectively.The MCT were statistically significant thinner in DR without and with ME eyes compared with control(P<0.001,P<0.001),the MCT were significant thinner in DR with ME eyes compared to that in DR without ME eyes(P<0.001).The inner layer of MCT was 84.03±7.89?m,81.45±6.86?m and 90.77±8.67?m for DR without ME,DR with ME and control,respectively.The inner layer of MCT were significant thinner in DR without and with ME eyes compared to that in control(P<0.001,P<0.001),the inner layer MCT showed no statistical difference between DR with ME eyes and DR without ME eyes(P=0.241).The outer layer MCT was 145.47±10.45?m,119.66±12.59?m and 191.55±14.33?m for DR without ME,DR with ME and control,respectively.The outer layer of MCT were significant thinner in DR without ME eyes and DR with ME eyes compared to that in control(P<0.001,P<0.001),the outer layer MCT were significant thinner in DR with ME eyes compared to that in DR without ME eyes(P<0.001).The best-corrected visual acuity(BCVA)(logMAR)was 0.41±0.37 and 0.70±0.45 for DR without ME and DR with ME.Univariate linear regression analysis showed a positive correlation between MCT and BCVA in either DR with or without ME groups(P=0.023,P=0.006).A stepwise multiple linear regression analysis demonstrated that the elucidative variables strong association with MCT were BCVA and central macular thickness(CMT)in DR eyes.Conclusion:In the eyes with DR,MCT was thinner compared to that of healthy control and this change was more substantial in ME eyes.MCT had a positive correction with BCVA.Our results indicate that the pathological change occurred in choroidal layer of the eyes with DR and this change correlated with impairment of BCVA.