The empty sella.

Empty sella (ES) is an extension or herniation of the subarachnoid space into the pituitary fossa through an incompetent sellar diaphragm that is commonly associated with clinical manifestations and endocrine abnormalities. The ES may occur secondary to a variety of pituitary disorders or as a primary entity. The pathogenesis of the primary ES appears to be multifactorial though the precise mechanisms remain unclear. The etiology of ES in children may differ from that in adults and is not uncommon in the presence of pituitary disorders. Patients with the ES should always undergo endocrine, neurologic, and ophthalmologic evaluation at the time of initial presentation and should be monitored as determined by the initial results. Treatment should be individualized as the clinical features and biochemical abnormalities vary widely among patients from the asymptomatic state with a normal hormone profile to sight-threatening visual disturbances, CSF rhinorrhea, and panhypopituitarism. The ES should not be considered as merely an incidental finding and clinicians should be aware of its varying presentations and ramifications.