Sella Turcica Dimensions on Radiographs

The length of the sella is determined by taking the greatest distance from the anterior wall of the sella to the most posterior portion of the posterior wall. The height is measured from the level of the tuberculum sellae to the most inferior portion of the floor of the sella.

The lower limits of normal for length and height of the sella on radiographs are 5 mm and 4 mm, respectively. The upper limits of normal for length and height of the sella on radiographs are 17 mm and 13 mm, respectively.

An abnormally small sella may indicate primary pituitary or growth hormone insufficiency, but is usually of no pathologic significance. An enlarged sella turcica may represent a normal variant or be due to a tumor (adenoma, prolactinoma, craniopharyngioma, meningioma), cystic lesion (Rathke cleft cyst, mucocele), aneurysm, pituitary hyperplasia (primary hypothyroidism), or empty sella syndrome.

In the case shown above, the length and height of the sella are 17 mm and 15 mm, respectively. As of this post, no follow-up study is available.

Special thanks to Dr. Jason Tsai for the case.

References

• Robertson WD, Newton TH. Radiologic assessment of pituitary microadenomas. AJR Am J Roentgenol. 1978 Sep;131(3):489-92.
• Taveras JM, Wood EH. Diagnostic neuroradiology: Williams & Wilkins Co, Baltimore (1964), pp. 1.96–1104.