Association of Vortex Vein Morphology with Punctate Hyperfluorescence on ICGA in Neovascular Age-Related Macular Degeneration.

Background/Objectives: Punctate hyperfluorescence (PH) on indocyanine green angiography (ICGA) is frequently observed in pachychoroid disease. However, the spatial relationship between PH lesions and vortex vein abnormalities remains unclear. This study quantified PH distribution in fellow eyes of patients with unilateral neovascular age-related macular degeneration (nAMD) and examined its association with vortex vein asymmetry and watershed-zone status. Methods: This retrospective observational study included 58 fellow eyes with PH from patients with unilateral nAMD. PH lesions were quantified on late-phase ICGA images using ImageJ software. Vortex vein distribution was classified as symmetric, superior-dominant, or inferior-dominant. Eyes were also classified by the presence of a horizontal watershed zone. PH distribution was compared by vortex vein morphology. Results: A watershed zone was absent in 14 eyes (24.1%). Vortex vein distribution was asymmetric in 27 eyes (46.6%), including 17 (29.3%) superior-dominant and 10 (17.2%) inferior-dominant. Overall, 3401 PH lesions were detected. Eyes without a watershed zone had significantly more PH lesions than those with a watershed zone (p = 0.002). The proportion of superior-region PH lesions differed significantly by vertical vortex vein predominance, with preferential distribution on the dominant side (p < 0.001). Although PH distribution did not differ significantly among the four quadrants overall, 30 eyes (51.7%) had >50% of PH lesions clustered in a single quadrant. Conclusions: PH lesions were preferentially distributed on the dominant side of vortex vein asymmetry, and eyes without a watershed zone had more PH lesions. These findings indicate that PH distribution and lesion burden are associated with vortex vein morphology and watershed-zone status and may reflect underlying alterations in choroidal venous drainage.