Localized Choriocapillaris Flow Deficits at Perforating Vessel Sites in Myopic Eyes

To investigate the association between perforating scleral vessels (PSVs) and choriocapillaris (CC) flow deficits (CCFDs) in otherwise healthy myopic eyes, and to identify predictors of localized flow deficits at PSV entry sites.

PSVs were localized using a combined en face and B-scan approach from swept-source OCTA volumes. CCFD% were quantified from signal-compensated 16-µm en face slabs using the Phansalkar method. Outcome measures included flow deficits at PSV sites (FDPSV), within 250 µm (FD250), and total CCFD. Mixed-effects regression was used to assess associations with demographic, refractive, and anatomic factors.

Fifty-two eyes from 31 healthy myopic (≤-0.5D) participants were included in the study. A total of 119 PSVs were identified. Correlation analyses demonstrated significant associations between FDPSV and age, axial length (AXL), and global CCFD (P < 0.05). In univariable analysis, older age and higher global CCFD (P < 0.001) were associated with increased FDPSV. In multivariable analysis, age (β = 0.23, P = 0.045), global CCFD (β = 1.02, P < 0.001), and PSV area (β = 16.5, P = 0.009) were significant predictors of FDPSV. AXL was inversely associated with FDPSV (β = -2.37, P = 0.010).

Localized CCFDs were consistently observed at PSV sites in myopic eyes. Although higher age, global CCFD, and PSV area were associated with greater localized deficits, longer AXL was associated with lower CCFDs, possibly reflecting scleral remodeling or altered PSV orientation in more significant myopia. These findings highlight the relevance of PSVs as early modulators of CC flow before the development of pathologic myopia.