The volume of the sella turcica in children: new standards.

Measurement of the sella turcica is valuable in the assessment of a variety of pituitary and other conditions. The volume, a more reliable measurement than sellar area, has been difficult to interpret for lack of adequate standards. This study presents mean and 10th, 50th, and 90th percentiles for sellar volume in normal children aged 6-16 years on the basis of measurements in 960 sets of skull radiographs made for orthodontic purposes. Sellar volumes are plotted against chronologic age, and against skeletal age for the 62% of measurements for which a simultaneous bone age determination had been made. As expected, the sellar volume increases with age: for example, mean volume for a boy 5 years 9 months to 6 years 8 months is 228 mm3, for a boy 15 years 9 months to 16 years 8 months is 640 mm3. For most age groups, sellar volume in males is greater than in females. Tenth and ninetieth percentiles for sellar volume are widely separated, giving a wide range of normal. Nevertheless they should be useful in assessing sellar volume in clinical situations.