Primary empty sella turcica: a radiological-anatomical correlation

The anatomical basis of the primary empty sella turcica is illustrated to emphasize that it represents a normal variant and not pathology. Unlike CT, the suprasellar structures including the visual system are clearly demonstrated by MRI. Intrasellar herniation of the superior visual system into a primary or secondary empty sella is well delineated by MR. Such herniation is said to be uncommon in primary empty sellae but not uncommon with secondary empty sellae. In the absence of herniation, on sagittal sections, the optic chiasm and optic nerves form a straight line with the optic canal while the floor of the third ventricle continues as a straight line to the mamillary bodies. Copyright (2000) Blackwell Science Pty Ltd