OCTA metrics monitor severity progression of Diabetic Retinopathy – 3-year longitudinal study

Author: José Cunha-Vaz (Portugal)

Co-authors: Inês Marques, Torcato Santos, Maria Madeira, Ana Santos, Conceição Lobo, Mary Durbin

Purpose

To examine retinal vessel closure metrics and neurodegenerative changes occurring in the initial stages of nonproliferative diabetic retinopathy (NPDR) and severity progression in a three-year period.

Setting/Venue

Clinical Trial Center – AIBILI, Coimbra - Portugal

Methods

Three-year prospective longitudinal observational cohort of eyes/patients with type 2 diabetes (T2D) using spectral domain-optical coherence tomography (SD-OCT) and OCT-Angiography (OCTA). Eyes were examined four times with one-year intervals. OCTA vessel density maps of the retina were used to quantify vessel closure. Thickness of the ganglion cell inner plexiform layer (GCL+IPL) was examined to identify retinal neurodegenerative changes. Diabetic retinopathy ETDRS classification was performed using the seven-field ETDRS protocol.

Results

A total of 78 eyes/patients, aged 52 to 80 years, with T2D and ETDRS grades from 10 to 47 were followed for 3 years with annual examinations. A progressive increase in retinal vessel closure demonstrated by higher decreases in vessel density (VD) correlated with retinopathy worsening identified by step-changes in ETDRS severity scale (p < 0.001). This decrease in VD varied between different individuals. No apparent correlation was found between neurodegenerative changes and retinopathy progression.

Conlusions

Retinal vessel closure in NPDR correlates with DR severity progression. Our findings provide evidence to support that OCTA metrics of vessel closure may be used as a surrogate for DR severity progression.

Financial Disclosure

Consultant: Carl Zeiss Meditec, Ciana Therapeutics, Alimera Sciences, Boehringer Ingelheim, Allergan, Bayer, Gene Signal, Novartis, Pfizer, Oxular, Roche, Sanofi, Vifor Pharma, Adverum Biotechnologies.