Abstract
Purpose :
To evaluate the relationship between disorganization of retinal inner layers (DRIL), external limiting membrane (ELM) loss, and ellipsoid zone (EZ) loss in the central subfield with retinal nonperfusion (RNP), Diabetic Retinopathy Severity Scale (DRSS) score and visual outcomes in eyes with diabetic macular edema (DME).
Methods :
The VISTA trial randomized 466 eyes to receive intravitreal aflibercept injection (IAI) 2 mg either every 4 weeks (2q4) or every 8 weeks (2q8) after 5 initial monthly doses, or laser. In this post-hoc analysis, DRIL (n=344), ELM loss (n=338), and EZ loss (n=335) were measured in the central 1000 µm of evaluable optical coherence tomography images at baseline and at weeks 52 and 100. RNP and DRSS score were assessed on fluorescein angiography and fundus photography, respectively. Observed cases were used in the analyses.
Results :
At week 100, the change from baseline with 2q4, 2q8, and laser was, respectively, –101.9, –84.1, and 9.5 for DRIL; –8.6, –36.1, and 67.6 for ELM loss; and –39.7, –53.3, and 57.3 for EZ loss. Most eyes treated with 2q4 and 2q8 showed improvement in DRIL versus laser (50.0% and 43.0% versus 26.6%, respectively), no change in ELM loss (49.4% and 43% versus 27.9%, respectively), and improvement or no change in EZ loss (55.2% and 47.7% versus 26%) from baseline to Week 100. Regardless of treatment group, at Week 100, there was a moderate to strong positive correlation between DRIL, ELM loss, and EZ loss (r range: 0.49 to 0.94); DRIL, ELM loss and EZ loss had a moderate negative correlation with best-corrected visual acuity (BCVA) (r values with 2q4, 2q8, and laser were, respectively, –0.49, –0.60, and –0.50 for DRIL; –0.47, –0.53, and –0.46 for ELM loss; and –0.49, –0.65, and –0.56 for EZ loss), and weak correlations with DRSS score and RNP area (r ≤0.38). At Week 100, eyes in the top (approximately ≥77 letters) tertile of BCVA had less DRIL, ELM loss, and EZ loss versus those in the bottom tertile (approximately ≤68 letters) regardless of treatment group.
Conclusions :
The majority of eyes with DME treated with IAI had improvements in DRIL, and maintenance or improvement in ELM and EZ loss through Week 100, which was not observed with laser. Retinal neurodegenerative changes had a moderate negative correlation with BCVA.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.