Large Choroidal Vessels as a Risk Factor for Idiopathic Choroidal Neovascularization

BACKGROUND AND OBJECTIVE: Idiopathic macular neovascularization (iCNV) is a rare and juvenile maculopathy affecting otherwise healthy individuals. The long-term visual prognosis is better than other CNVs. However, scarce insights on the disease mechanisms have been identified. The role of mechanical compression exerted by a pachyvessel is explored in this study. PATIENTS AND METHODS: Patients affected by iCNV, with no evidence of previous retinal/uveitis diseases, were retrospectively enrolled. For every patient, best-corrected visual acuity (BCVA), optical coherence tomography (OCT) data and angiographic exams were collected at baseline and after antiVEGF therapy (follow-up). OCT parameters, including choroidal thickness (ChT), were compared with a dataset from a control group of healthy subjects. RESULTS: Sixteen eyes of 16 patients (18.7% male, 41.2 ± 14.9 mean age) were enrolled. The mean number of intravitreal injections of anti-VEGF to reach anatomical stability was 2.2 ± 1.68. Twelve eyes (75%) displayed at least one large choroidal vessel below (10/12) or in strict proximity (2/12) of the neovascular net. The mean pachyvessel diameter was 80.4 ± 33.3 µm. No statistically significant differences were found at baseline between ChT parameters in the iCNV group and the control group, and no changes in ChT were observed in the iCNV group after the intravitreal treatment. CONCLUSION: Pachyvessels may act as a local factor in favoring the onset of iCNV. Choroidal thickness did not change during follow-up, excluding inflammatory congestion.