The empty sella and pituitary adenomas. A theory on the causal relationship.

In 44 consecutive patients with sellar volume larger than 1100 mm3, computer tomography showed that 20 had an empty or partly empty sella. None had radiological evidence of a suprasellar tumor. 10 of the 20 patients had experienced episodes with acute neurological symptoms presumably reflecting a pituitary apoplexy. It is suggested that an unknown proportion of intrasellar adenomas may disappear as a result of an infarction, which may comprise the entire adenoma or part of it--leaving an empty or partly empty sella as diagnosed by computer tomography. Air encephalography will demonstrate the empty sella only if the diaphragmatic aperture is large enough to allow cisternal herniation. The infarction may present clinically with no, slight or severe acute neurological symptoms. Late consequences of a pituitary adenoma infarction may be rhinorrhea or hydrocephalus.