OCT-Angiography as a reliable prognostic tool in laser-treated proliferative diabetic retinopathy: The RENOCTA Study

Area of Science:

• Ophthalmology
• Medical Imaging
• Diabetic Retinopathy Research

Background:

• Proliferative diabetic retinopathy (PDR) is characterized by retinal neovascularizations (RNVs).
• Assessing the efficacy of photocoagulative laser treatment (PLT) for PDR is crucial for patient outcomes.

Purpose of the Study:

• To quantitatively evaluate changes in RNVs in PDR patients before and after PLT using Optical Coherence Tomography Angiography (OCT-A).
• To determine if OCT-A metrics can predict treatment response and the need for additional interventions.

Main Methods:

• Patients with PDR underwent fluorescein angiography (FA) and OCT-A before and after PLT.
• Quantitative analysis of RNVs area and leakage on FA.
• OCT-A was used to compute RNVs area, vascular perfusion density (VPD), vessel length density (VLD), and fractal dimension.
• Full-retinal VPD was assessed to detect laser-induced perfusion changes.

Main Results:

• A statistically significant reduction in RNVs area (p=0.0002) and VPD (p=0.0001) was observed after PLT.
• A significant decrease in VLD (p=0.0002) was also noted.
• Eyes with a reduction of RNVs area or VPD >= 40% were less likely to require additional treatment.
• Mean full-retinal VPD showed a slight but significant decrease post-treatment (p=0.02).

Conclusions:

• Quantitative OCT-A is a valuable non-invasive tool for assessing PLT efficacy in PDR.
• A reduction in RNVs area or VPD of 40% or more may indicate successful treatment, potentially avoiding further interventions.
• Retinal perfusion impairment appears to progress independently of the laser treatment itself.