Macular Choroidal Thickness Measurement by Enhanced Depth Imaging Optical Coherence Tomography in Type (II) Diabetes Mellitus Patients

Abstract

PURPOSE: To evaluate the central (macular) choroidal thickness in diabetic patients with type (II) diabetes mellitus (DM) using enhanced depth imaging optical coherence tomography (EDI-OCT). METHODS: A prospective clinical interventional study included 100 eyes of 100 subjects divided into two groups: Group (A) included 50 eyes of 50 diabetic patients with type (II) DM and Group (B) included 50 eyes of 50 age-matched normal healthy controls with no gender or laterality specification. The central choroidal thickness (CCT) was measured from the posterior edge of RPE to the choroid-scleral junction at 1500µm intervals up to 3000µm from the fovea using EDI-OCT in 11 quadrants and regions. RESULTS: Mean age in group (A) was 42±7 years (range, 26-50 years), and 39±9 years (range, 25-50 years) in group (B). Mean duration of DM was 7.96±3.9 years in group (A). Subfoveal CCT was found to be 291±42µm in group (A) (275.31±31µm for no apparent retinopathy (No DR), 298±42µm for non-proliferative diabetic retinopathy (NPDR), 309±58µm for proliferative diabetic retinopathy (PDR), 277±29µm for diabetic macular edema (DME) absent and 306±47µm for DME present) while it was 284±54µm in group (B). There was a statistically significant positive correlation between CCT and DM duration (P≤0.05). CONCLUSION: Choroidal thickness was found to be correlated with the stage of diabetic retinopathy (DR). Progressive thickening of the choroid with the progression of DR and/or the development of DME may reflect the concurrent progression of diabetic choroidopathy.