Factors associated with the development of exudation in treatment-naive eyes with nonexudative macular neovascularization

Purpose To identify the predictive factors for development of exudation in patients with treatment-naïve nonexudative macular neovascularization (MNV). Methods We retrospectively analyzed 61 treatment-naïve patients with nonexudative MNV who had not received treatment for nonexudative MNV before the exudation developed. Baseline characteristics and changes in MNV were evaluated using multivariate modeling to determine the potential risk factors for exudative conversion. Results Exudation development was identified in 31.1% (19/61 eyes) of the study eyes during the 46.2 ± 8.2-month mean follow-up period. The mean period of development of exudation from the baseline was 21.5 ± 6.7 months. Multivariate Cox regression analysis identified that older age (hazard ratio [HR] of 1.380, 95% confidence interval [CI] 1.129–1.688, P = 0.008), larger MNV area at baseline (HR of 1.715, CI 1.288–2.308; P = 0.006), increase of MNV area by doubling (HR of 4.992, CI 1.932–9.246; P = 0.002), and retinal pigment epithelium (RPE) elevation more than 100 μm (HR of 1.017, CI 1.006–1.233; P = 0.015) were associated with increased risk of the development of exudation. Conclusion Older age, larger MNV area, increasing MNV area, and higher RPE elevation were associated with an increased risk of exudative conversion in patients with treatment-naïve nonexudative MNV. Identifying these risk factors may be helpful in establishing treatment strategies and monitoring patients.