AIM: To investigate the relationship between the subfoveal choroidal thickness(SFCT)and both choroidal hemodynamic index and glycosylated hemoglobin in diabetic subjects.

METHODS: Seventy-eight type 2 diabetic patients(156 eyes)from ophthalmology and endocrinology ward of our hospital were enrolled in this study, including 39 females and 39 males, with a mean age of(59.8±6.2)years. According to early treatment diabetic retinopathy study(ETDRS)grading method, all samples were divided into diabetic retinopathy(DR)group, mild or moderate nonproliferative diabetic retinopathy group, severe nonproliferative diabetic retinopathy(NPDR)group and proliferative diabetic retinopathy(PDR)group. The SFCT and choroidal hemodynamic index were measured by enhanced depth imaging optical coherence tomography(EDI-OCT)and Color Doppler Imaging. Recording glycosylated hemoglobin content of all samples. Using multivariate linear regression to analyse the relationship between the SFCT and both choroidal hemodynamic index and glycosylated hemoglobin.

RESULTS: The end diastolic velocity(EDV)was significant higher and the SFCT was significant thinner in no diabetic retinopathy(NDR)group than other groups. There was no significant difference of peak systolic velocity(PSV)between four groups.The resistance index(RI)was significant higher in severe NPDR group than NDR group and mild or moderate group,the RI in PDR group was hihgest than other group with statistically significance.The SFCT was correlated positively(b=0.540,P<0.001)with the glycosylated hemoglobin. No significant correlation was found between the SFCT and the choroidal hemodynamic index(DR,P=0.341; PSV,P=0.770; EDV,P=0.131; RI,P=0.084).

CONCLUSION: Our results suggest that there is no significant correlations between the SFCT and the choroidal hemodynamic index; glycosylated hemoglobin is one of the factors that affect the SFCT in diabetic patients.