Fig. 1.

Axial measurements. a–c Vaginal axial measurement. Selected slices show typical vaginal axial measurements. Points 1 to 5 are used to identify the coapted anterior and posterior vaginal wall in a. Points 1 to 8 are used to identify the anterior vaginal wall (1 to 5) and posterior vaginal wall (1, 8, 7, 6, and 5) in b, with the largest separation between the anterior and posterior vaginal walls being at least 1 cm. When only the posterior vaginal wall was visible in c, points 1 to 5 were only used to identify the posterior vaginal wall. 1 is always the lateral-most point on the right and 5 is always the lateralmost point on the left. d–f Cervix measurement. Five points on axial slices were used to identify the cervix location. Points 1 and 2 were placed on the lateralmost margins on the right and left respectively. Likewise, points 3 and 4 were used to mark the anterior- and posteriormost margins. Point 5 marks the center of the cervix, with the first point 5 in d marking the location of the cervical os. g–i Bony pelvis mid-plane. The mid-sagittal plane of the pelvis was identified using three points placed on specific landmarks on different axial slices: point 1 at the center of pubic symphysis, point 2 at the center of the distal sacrum, and 3 on the mid-sacrum. V vagina, R rectum, BI bladder (DeLancey©)