Abstract:AIM: To evaluate and characterize the macular thickness and macular volume in patients of different stages of diabetic retinopathy with special-domain optical coherence tomography(SD-OCT).
METHODS: Totally 40 patients(78 eyes)with diabetic retinopathy were recruited in the study from January 2016 to January 2017 in our hospital. According to the international clinical classification of diabetic retinopathy, 20 cases(40 eyes)were categorized as non-proliferative diabetic retinopathy(NPDR)group and 20 cases proliferative diabetic retinopathy(PDR)group(38 eyes). All subjects were examined and analyzed with Early Treatment Diabetic Retinopathy Study(ETDRS)subfields, which were embedded in HS(Haag-Streit)with diameter of 1, 3 and 6mm.The changes of retinal thickness and volume of the macular center were measured.
RESULTS: The thickness of macular foveolar in NPDR group and PDR group were 252.57±31.36μm, 362.47±20.81μm. The retinal thickness of inner superior subfield(ISM)and inner nasal subfield(INM)were the thickest; that of inner inferior subfield(IIM)was next to ISM and INM, and that of inner temporal subfield was the thinnest. Of the outer subfields, the retinal thickness of outer superior subfield(OSM)was the thickest; that of outer nasal subfield(ONM)was next to OSM, and that of outer temporal subfield(OTM)and outer inferior subfield(OIM)was the thinnest. The value of macular central concave thickness and retinal thickness in each quadrant of the NPDR group were less than those of the PDR group, the difference was statistically significant(P<0.05). The volume(V)of macular center in NPDR group and PDR group were 0.20±0.02mm3, 0.28±0.16mm3, the upper and nasal sides of the middle part of the partition were the largest, the inferior and the temporal side were the smallest. The nasal side of the outer loop was the largest, the upper was the second, the temporal side and the inferior were the smallest. The volume of macular central fovea and the retinal volume in each quadrant of the NPDR group were smaller than those of the PDR group, the difference was statistically significant(P<0.05).
CONCLUSION: The changes of retinal thickness and volume in macular central fovea were related with the progression of diabetic retinopathy. Using OCT to analyze the macular thickness and macular volume in different stages of diabetic retinopathy, helps physicians to understand the morphological changes of macular region and its surrounding macular degeneration with the severity of diabetic retinopathy, and provide a basis for better analysis of the changes of the structure of macular in different severity diabetic retinopathy.
