Correlation between Imaging Morphological Findings and Laboratory Biomarkers in Patients with Diabetic Macular Edema

Abstract

Purpose. To investigate the potential association between peripheral blood biomarkers and morphological characteristics of retinal imaging in patients with diabetic macular edema (DME). Methods. Participants in this cross-sectional study were 36 consecutive patients (36 eyes) with treatment-naïve DME, who underwent spectral domain-optical coherence tomography (SD-OCT), fundus photography, and fundus fluorescein angiography (FFA). In addition, peripheral blood samples were taken to evaluate full blood count and biochemical parameters. Correlation between imaging characteristics and laboratory parameters was examined. Results. Eyes with central subfield thickness greater than 405 μm presented significantly higher neutrophils/lymphocytes ( $p=0.043$ ) and higher lipoprotein (a) compared to eyes with $\text{CST}<405\mu \text{m}$ ( $p=0.003$ ). Presence of hyperreflective foci on SD-OCT was associated with significantly higher white blood cell count ( $p=0.028$ ). Ellipsoid zone disruption was associated with significantly lower hematocrit ( $p=0.012$ ), hemoglobin ( $p=0.009$ ), and red blood cell count ( $p=0.026$ ), as well as with higher lipoprotein (a) ( $p=0.015$ ). Macular ischemia on FFA was associated with significantly higher monocytes ( $p=0.027$ ) and monocytes/HDL ( $p=0.019$ ). No significant associations were found between laboratory parameters and subretinal fluid, intraretinal fluid, exudates, cysts, disorganization of inner retinal layers, epiretinal membrane, and external limiting membrane condition. Conclusion. Specific imaging morphological characteristics were found to be associated with laboratory parameters in patients with DME. These findings may shed light on the pathophysiology of DME and its correlation with the development of specific clinical signs.