Correspondence between OCT Characteristics and Biochemical Parameters in Diabetic Macular Edema

Objective: The purpose of this study is to evaluate the potential association between peripheral blood parameters and the morphological characteristics of retinal imaging obtained via spectral-domain optical coherence tomography (SD-OCT) in patients with treatment-naïve diabetic macular edema (DME). Materials and Methods: This cross-sectional study included 100 patients with treatment-naïve DME. All participants underwent spectral-domain optical coherence tomography (Optovue) and fundus photography. Peripheral blood samples were collected to assess complete blood count (CBC), glycated hemoglobin (HbA1c), blood glucose, serum urea, serum creatinine, and lipid profile. Results: Central subfield thickness (CST) was significantly associated with serum HDL (P= 0.003). Intraretinal fluid (IRF) was linked to serum triglycerides (P=0.006), serum VLDL (P=0.001), and cholesterol- to-HDL ratio (P= 0.001). Subretinal fluid (SRF) showed an association with blood glucose (P= 0.028). Hyperreflective foci (HF) were related to total blood count (P= 0.001), monocyte count (P= 0.001), cholesterol-to-HDL ratio (P= 0.045), LDL-to-HDL ratio (P= 0.003), and serum urea (P= 0.051). Disorganization of the retinal inner layers (DRIL) correlated with total blood count (P=0.047), lymphocyte count (P= 0.008), blood glucose (P= 0.007), and LDL-to-HDL ratio (P= 0.046). Epiretinal membrane (ERM) was associated with blood glucose (P= 0.001), total cholesterol (P= 0.022), serum LDL (P= 0.025), cholesterol-to-HDL ratio (P= 0.013), and LDL-to-HDL ratio (P= 0.008). Ellipsoid zone (EZ) and external limiting membrane (ELM) disruptions were linked to blood glucose, serum LDL, and VLDL. Hard exudates correlated with blood cell counts, glucose, HbA1c, urea, and creatinine (P< 0.05). CONCLUSION: Systemic factors are significantly associated with retinal morphological patterns in DME, highlighting the potential for modifying these factors to influence disease progression and treatment response.