Metabolic, Microvascular, and Structural Predictors of Long-Term Functional Changes Evaluated by Multifocal...

Area of Science:

• Ophthalmology
• Diabetology
• Medical Imaging

Background:

• Type 1 diabetes mellitus (DM1) can lead to diabetic retinopathy, affecting retinal microvasculature and photoreceptor cells.
• Understanding the interplay between metabolic control, vascular changes, and visual function is crucial for managing DM1 complications.

Purpose of the Study:

• To investigate the pathogenic links between metabolic factors, photoreceptor alterations, retinal microvascular perfusion, and visual function in DM1 patients.
• To analyze these connections using multifocal electroretinography (mfERG) and advanced imaging techniques.

Main Methods:

• Prospective observational cohort study of DM1 patients with mild nonproliferative diabetic retinopathy over 4 years.
• Multimodal imaging including OCT angiography and adaptive optics (AO) for retinal microvascular and photoreceptor analysis.
• mfERG was used to assess retinal electrical responses, correlating with metabolic (HbA1c) and imaging parameters.

Main Results:

• HbA1c levels significantly influenced the implicit time of the foveal response (R1 IT) and the overall response amplitude (R1 + R2 RAD).
• Photoreceptor structure (Hpi%) and choriocapillaris flow deficit (CC FD%) impacted R1 RAD, while parafoveal microvascular density (SCP, DCP) affected R1 + R2 IT.
• Cone dispersion (LDi) and packing (Hpi%) were strongly associated with parafoveal functional parameters.

Conclusions:

• Microvascular alterations and glycemic control are critical determinants of long-term morphofunctional changes in photoreceptors in DM1.
• These findings highlight the importance of managing metabolic factors and monitoring vascular health to preserve visual function in diabetic patients.