ImportanceIdentifying changes of peripapillary vessel density in highly myopic eyes with peripapillary intrachoroidal cavitation by optical coherence tomography angiography. BackgroundTo investigate peripapillary vessel density and its relationship with other ocular parameters in highly myopic eyes with peripapillary intrachoroidal cavitation. DesignHospital-based, cross-sectional study. ParticipantsThirty-five highly myopic eyes with peripapillary intrachoroidal cavitation, 46 highly myopic eyes without peripapillary intrachoroidal cavitation and 36 normal eyes were included in this study. MethodsAll participants underwent optical coherence tomography angiography to image the retinal vasculature in the peripapillary areas, including the radial peripapillary capillaries and optic nerve head layer. Correlations between vessel density and ocular metrics were analysed. Main Outcome MeasuresPeripapillary vessel density. ResultsIn highly myopic eyes, vessel density was significantly lower in eyes with peripapillary intrachoroidal cavitation than in those without in peripapillary (P = 0.014, P = 0.037), inferotemporal (P < 0.001, P < 0.001) and superotemporal (P = 0.014, P = 0.009) areas. In the radial peripapillary capillaries layer, vessel density was negatively correlated with peripapillary atrophy area (P = 0.012) and myopic maculopathy (P = 0.002), and in the optic nerve head layer, it was negatively associated with a diagnosis of peripapillary intrachoroidal cavitation (P = 0.012) and myopic maculopathy (P < 0.001). In addition, it was positively correlated with retinal nerve fibre layer thickness in both layers (P < 0.001). Conclusions and RelevanceHighly myopic eyes with peripapillary intrachoroidal cavitation had lower peripapillary vessel densities, especially in the temporal area, than those without.