Cephalometric analysis and the size of ST

Each cephalometric radiograph was traced with Steiner analysis by using digital software (Uceph version 4.2.1, Chengdu ya xun Technology Co., Ltd). The ST dimensions were measured with the same software by (R.A) author, consistent with the approach defined by Silverman [17] as cited by Axelsson et al. [18] as shown in (Fig. 1). The length of ST was evaluated by drawing a line between the tips of tuberculum sellae and dorsum sellae. The depth of ST was detected as a constructed, perpendicular line from the former line to the deepest point on the floor surface. The anteroposterior diameter (A.P diameter) of ST was calculated as a distance between the tuberculum sellae and the farthest point on the fossa's posterior internal wall.

Normal ST morphology and reference lines used for measuring sellae size: TS, tuberculum sellae; DS, dorsum sellae; BPF, base of the pituitary fossa; black line, length of sellae; dashed line, Antero-posterior diameter of sellae; dotted line, depth of sellae