Tension pneumocephalus after transsphenoidal surgery for acromegaly.

: The Authors report the case of a 27-year-old man who developed intraventricular and subarachnoid tension pneumocephalus after removal of a large pituitary adenoma via the transnasal approach. This exceptional complication was probably caused by the combined action of a cerebrospinal fluid fistula plus an external lumbar subarachnoid drain, and resolved after removal of the spinal catheter. Such a conservative treatment was allowed in this case by the absence of a shift of midline structures due to bilateral intraventricular air collection. Usually, however, tension pneumocephalus is a life-threatening condition that requires prompt intervention. Meticulous attention to the cerebrospinal fluid draining system is needed in patients with a fistula to avoid the development of this unusual complication.