Perforating scleral vessel angular metrics as a structural biomarker of myopic choroidal neovascularisation

BACKGROUND: To quantitatively assess the entrance angle variability and location of perforating scleral vessels (PSVs) in highly myopic eyes and to investigate its association with myopic choroidal neovascularisation (mCNV) versus lacquer cracks (LC). METHODS: Entrance angles from the sclera to choroid were measured on each B-scan OCT using ImageJ and associated angle metrics were calculated per PSVs. Additional variables included subfoveal choroidal thickness (SFCT) and vessel-to-fovea distance (VFD). In mCNV eyes the total number of injections and treatment duration were also accounted. RESULTS: A total of 42 eyes were included, 25 with mCNV and 17 with LC. Eyes with mCNV demonstrated significantly greater PSV angular variability including angular standard deviation, and their normalised metrics compared to LC eyes (all p < 0.001). VFD was shorter in the mCNV group (50.2 ± 52.6 µm vs. 91.5 ± 39.6 µm, p = 0.006). Normalised angle metrics correlated positively with the total number of anti-VEGF injections (r ≈ 0.37, p < 0.05), whereas no association was observed with treatment duration. In multivariable regression, no predictors reached statistical significance although normalised angle range (NAR) showed a trend toward a negative association with VFD (p = 0.060). CONCLUSIONS: PSV angular variability was markedly greater in mCNV eyes and correlated with anti-VEGF injection burden reflecting higher treatment intensity but not longer disease duration. These findings suggest that PSV geometry influences LC and mCNV, may serve as an imaging biomarker of disease activity in mCNV. Shorter VFD and greater angular dispersion likely reflect structural and hemodynamic alterations predisposing to mCNV.