Hypopituitarism caused by intrasellar aneurysms.

OBJECTIVE

To determine the prevalence, clinical presentation, and outcome of hypopituitarism due to an intrasellar aneurysm.

PATIENTS AND

METHODS

We performed a retrospective review of Mayo Clinic, Rochester, Minn, medical records from 1950 through 1995. We calculated the prevalence of hypopituitarism, characterized the clinical presentation, and evaluated postoperative outcomes.

RESULTS

Of 4087 patients with a diagnosis of hypopituitarism, 7 had hypopituitarism due to an intrasellar aneurysm, accounting for a prevalence of 0.17%. Adrenal, thyroid, and gonadal deficiencies were observed in 7, 6, and 5 patients, respectively. The prolactin level was increased in the 2 patients in whom it was measured. No patient had diabetes insipidus. All had visual impairment. In 5 patients an intrasellar aneurysm of the internal carotid artery was diagnosed preoperatively based on 1 or more imaging procedures. In the other 2 patients (1 with an internal carotid artery aneurysm and 1 with an anterior cerebral artery aneurysm), the diagnosis was made at surgical exploration. Four patients underwent a surgical procedure: 2 had direct packing of the aneurysm, and 2 had a bypass with proximal carotid occlusion or aneurysm trapping. Pituitary function remained unchanged postoperatively.

CONCLUSION

An intrasellar aneurysm is a rare cause of hypopituitarism (0.17% of cases). Preoperative diagnosis is essential for successful surgical outcomes. Hypopituitarism is usually permanent.