The pituitary fossa: a correlative anatomic and MR study.

This study characterizes the normal appearance of the pituitary fossa in partial saturation magnetic resonance (MR) images. In sagittal images, the pituitary fossa appears inhomogeneous. Correlation of sagittal MR images in normal subjects with sagittal cryomicrotomic images in cadavers suggests that the highest intensity signal from the posterior-inferior pituitary fossa is due to a fat pad. This conclusion was supported by MR images and postmortem cryotome sections obtained in normal subhuman primates. The cause of the less constant, low intensity signal was less certain. The height of the pituitary gland in sagittal images was usually less than 8 mm, and the upper surface was flat or concave.