Stanje kapilarne mreže u makuli kod pacijenata sa dijabetesom bez klinički vidljive dijabetičke retinopatije u odnosu na zdravu populaciju

Abstract

Introduction: Optical Coherence Tomography Angiography (OCT-A) was used to investigate the changes in retinal and choriocapillaris vessel density (VD) in patients affected by type 2 diabetes mellitus (T2DM) with further investigation of alteration to the autoregulation of the capillary network in the macular zone occurs before the clinical manifestation of diabetic maculopathy or retinopathy. OCT-A biomarkers that indicate early vascular changes in the capillary bed were: central foveal thickness (CFT), the foveal avascular zone (FAZ), foveal density (FD), and vessel density (VD). The main aim was to determine the state of the capillary network in the macula in patients with diabetes without clinically visible diabetic retinopathy in comparison to the healthy population. Method: A total of one hundred sixty-six eyes of 83 patients with T2DM and without diabetic retinopathy, were recruited in this observational prospective study. The control group consisted of 66 eyes in 33 healthy subjects. Superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris were regions where vessel density (VD) was measured. Results: There were significant differences in VD of the SCP and DCP among the control and study groups. The VD of the choriocapillaris revealed a statistically significant reduction in the study group in comparison to the control. The patients with T2DM showed a significantly decreased VD concerning control in different macular regions. Thickness in several macular regions significantly decreased in the study group compared to the control. Useful information regarding the vascular changes in patients with T2DM were assessed through the quantitative analysis of retinal and choriocapillaris blood flow obtained with OCT-A. Diabetic subjects have a significantly higher mean value of CFT compared to the mean value of the control group, followed by a significantly lower density of the capillary network. In the case of the size of the FAZ, in diabetic patients, FAZ is enlarged but no statistically significant difference was found. Conclusion: OCT-A parameters associated with retinal superficial and deep retinal vessel density have lower values detected in diabetic patients without DR in comparison to healthy subjects. Diabetes impacts the values of CFT and FD but does not impact the size of the FAZ. According to obtained results, OCT-A could be considered as a potential biomarker used for the risk of developing DR in patients with diabetes without DR evaluation.