Choroidal changes and association with Gaussian curvature in high myopic eyes with posterior staphyloma in ultra‐wide‐field optical coherence tomography angiography

To evaluate choroidal changes in high myopic (HM) patients with posterior staphyloma (PS) and explore their association with Gaussian curvature (K) using ultra-wide-field optical coherence tomography angiography (UWF-OCTA). HM patients with wide macular PS (Type I PS) and without any PS (control) were recruited. Highest K values (Kmax) and choroidal parameters-vessel flow density (VFD), choroidal vascularity volume (CVV) and index (CVI), thickness, and volume-were compared in central and peripheral regions, and the fovea-centered 12-mm ETDRS quadrants of 24 × 20 mm UWF-OCTA images. Associations between choroidal parameters and K values in Type I PS eyes were analysed using multiple linear regression analysis, controlling for the confounding effect of AL. Type I PS eyes showed increased Kmax in various subregions (p < 0.05), except the 12-mm ETDRS superior quadrant. CVV, choroidal thickness, and volume were higher in the peripheral region of the UWF-SS-OCTA image in Type I PS eyes (p < 0.05). Central CVI and large and medium choroidal vascular layer-VFD were significantly lower in Type I PS eyes (p < 0.05). Correlation analysis revealed a negative association between macular Kmax and central CVI (p < 0.05). In the peripheral region, Kmax showed a positive correlation with choroidal thickness and volume (p < 0.05). These correlations were partially confirmed across several quadrants of the 12-mm ETDRS grid. Type I PS eyes exhibit attenuated choroidal perfusion and a potentially reorganized choroidal structure and circulation, associated with Gaussian curvature severity. UWF-OCTA shows promise for non-invasive visualization of the choroidal alterations in PS.