Fig 1. Sagittal images from cases 1, 2, 3, 4, 6, and 7 demonstrating the typical position of the dorsal SSS AG identified in this study (arrows). Case 3, Sagittal reconstruction of FSPGR postcontrast T1-weighted image (3T); case 6, sagittal reconstructed image from 2-mm axial FSE T2-WI (3T); all others, sagittal FSE T2-weighted images.