PURPOSE: To explore the characteristics of retinal, choroidal, and retrobulbar blood flows in myopic patients with posterior staphyloma (PS) using ultra-widefield optical coherence tomography angiography (UWF-OCTA) and Color Doppler imaging (CDI). METHODS: The retrospective cross-sectional study enrolled 134 adults with high myopia from the Eye and ENT Hospital of Fudan University from December 2021 to September 2022. After propensity score matching, 45 eyes of 30 patients and 45 eyes of 32 patients were included in the PS and non-PS (NPS) groups, respectively. Retinal, choroidal, and retrobulbar blood flow parameters were obtained from UWF-OCTA and CDI. Parameters were compared between the PS and NPS groups, as well as among different PS types. RESULTS: There were no statistical differences in age, sex, axial length, spherical equivalent, intraocular pressure, or best-corrected visual acuity between the PS and NPS groups or in the different types of PS. The PS group had lower fovea, parafovea, and perifovea choroidal vessel volume (CVV) compared to the NPS group (all P <
0.05). The wide and narrow macular types of PS had significantly thinner choroidal thickness (CHT), lower CVV, and lower choroidal stromal volume (CSV) than other groups (all P <
0.01). PS occurrence was correlated with the decrease in CVV and posterior ciliary artery end-diastolic velocity (PCA-EDV), and the decrease in PCA-EDV was an associated factor for PS. The wide and narrow macular types of PS were correlated with the decrease of CHT, CVV, and CSV
the decrease in perifovea CHT was an associated factor for wide and narrow macular types of PS. CONCLUSIONS: Change in blood flow of the PCA was associated with PS occurrence. Reduced CHT in the temporal perifoveal region was a factor associated with both wide and narrow macular types of PS. Further longitudinal study will help to investigate the causal relationship between PS and changes in blood flow.