# Morphology of Macular Neovascularization in Age-Related Macular Degeneration Influences Treatment Requirement and Visual Outcome After 1 Year

## TL;DR

The study shows that the structure of abnormal blood vessels in the eye can predict how much treatment is needed and how well vision will improve in patients with a type of age-related eye disease.

## Contribution

The study identifies specific OCT and OCTA parameters that predict treatment needs and visual outcomes in neovascular age-related macular degeneration.

## Key findings

- Persistent subretinal fluid and pigment epithelium detachment correlate with a higher need for intravitreal injections.
- Baseline central retinal thickness and follow-up changes are linked to visual acuity outcomes.
- MNV area, vessel length, and fractal dimension in OCTA correlate with visual acuity after one year.

## Abstract

Background/Objectives: To evaluate the potential of Optical Coherence Tomography (OCT) and OCT angiography parameters in predicting treatment requirements and visual outcomes after one year in therapy-naïve eyes with neovascular age-related macular degeneration (nAMD). Methods: A retrospective study of 96 therapy-naïve eyes newly diagnosed with nAMD was carried out. All eyes received baseline OCT and OCTA. Follow-up OCT after initial upload was then carried out, involving three intravitreal injections (IVIs) with anti-Vascular Endothelial Growth Factor (anti-VEGF) at four-week intervals. OCT parameters, including intraretinal fluid (IRF), subretinal fluid (SRF), pigment epithelium detachment (PED), and central retinal thickness (CRT), were assessed qualitatively and quantitatively. Macular Neovascularization (MNV) morphology at baseline was described in terms of area, total vessel length, flow density, and fractal dimension. OCT and OCTA parameters were correlated with best corrected visual acuity (BCVA) and number of administered IVIs after 1 year of treatment. Results: Eyes with persistent subretinal fluid (SRF) or both intraretinal fluid (IRF) and SRF after upload showed a significantly higher need for IVIs (p < 0.01). Also, pigment epithelium detachment (PED) presence at baseline (p < 0.05), PED height at baseline (p < 0.01), PED presence after upload (p < 0.01), and PED height after upload (p < 0.01) were each correlated with a greater number of IVIs. Decrease in PED height during upload was accompanied by a lower number of IVIs (p < 0.01). All the aforementioned parameters had no influence on BCVA after 1 year (p > 0.05). Baseline central retinal thickness (CRT) was linked to worse BCVA at 12 months (p < 0.05), but not the number of IVIs. Follow-up CRT correlated with worse BCVA (p < 0.01) and more IVIs (p < 0.01), while CRT decrease was associated with better BCVA (p < 0.05) and fewer IVIs (p < 0.01) at 1 year. In OCTA, area and total vessel length of MNVs were correlated with BCVA after 1 year (p < 0.01) but had no influence on number of IVIs (p > 0.05). Flow density had no influence on either outcome parameter (p > 0.05). Fractal dimension was associated with BCVA (p < 0.01) and number of IVIs (p < 0.05) after 1 year. Conclusions: MNV area, vessel length, and fractal dimension in OCTA, along with fluid distribution in OCT at baseline and after follow-up, may serve as indicators of treatment needs and visual outcomes after one year. Further studies with longer observation periods and the use of deep learning models are needed to improve analyses and to verify the applicability of these findings to clinical practice.