Baseline and 3-Year Follow-Up Changes in Retinal Neurovascular Structures Assessed by OCT and OCTA in Pediatric Type 1 Diabetes Without Retinopathy

Purpose: To investigate longitudinal changes in retinal neurovascular components over a 3-year period using optical coherence tomography (OCT) and OCT angiography (OCTA) in pediatric and adolescent individuals diagnosed with type 1 diabetes mellitus (DM) but without signs of diabetic retinopathy (DR). Methods: Individuals with type 1 DM and no clinical signs of DR were evaluated between May and September 2022. Quantitative evaluation was performed on neurovascular components of the retina in both the macular and peripapillary regions. Data from the previous 3 years (Group 1) were compared with current data (Group 2). Relationships between pubertal stage, duration of diabetes, and glycosylated hemoglobin (HbA 1c ) levels were examined. Results: The study included 92 eyes from 46 participants diagnosed with type 1 DM. Group 2 had significantly lower vessel densities in the foveal and parafoveal superficial capillary plexus and deep capillary plexus than Group 1. However, central foveal thickness (CFT), inner retinal thickness, peripapillary retinal nerve fiber layer thickness, and nasal inferior disc-vessel density were significantly higher in Group 2. A significant relationship was found between pubertal stage and vessel densities in both the superficial capillary plexus and optic disc regions. HbA 1c levels and diabetes duration correlated with the foveal avascular zone area and superficial capillary plexus/deep capillary plexus-vessel densities. Conclusions: Initially, the peripapillary microvascular structure is more affected than the macula in type 1 DM. However, after 3 years, microvascular macular decline becomes more prominent. Additionally, foveal retinal thickness and peripapillary retinal nerve fiber layer thickness were significantly increased.