The 'Empty' Sella Turcica—A Manifestation of the Intrasellar Subarachnoid Space

The term “empty sella” is a gross descriptive term introduced by Busch in 1951 (3) and applied to the appearance of the sella turcica when the diaphragma sellae is incomplete or forms only a small peripheral rim and the pituitary gland is not visible grossly as one views the sella turcica from above at necropsy or at surgery. Actually, the pituitary gland is not absent, but is flattened in such a manner as to form a thin layer of tissue at the bottom of the sella turcica. In 1924, Schaeffer (35) described the gross appearance of the diaphragma sellae in 125 cases and noted that it varied from a very dense and complete roof, transmitting the infundibulum, to a mere peripheral rim with a huge infundibular foramen. Busch (3) grossly examined 788 sellae of patients with no known pituitary disease and described three main types of the diaphragma sellae. In Type 1-A the diaphragma sellae forms a complete covering transmitting the hypophyseal stalk. Type 1-B exhibits a slight funnel-shaped depression in the comp...