Contribution of Intrasellar Pressure Elevation to Headache Manifestation in Pituitary Adenoma Evaluated With Intraoperative Pressure Measurement.

BACKGROUND Headache frequently occurs in patients with pituitary adenoma and is reported in large as well as small adenomas. However, the exact mechanism of headache derived from pituitary adenoma remains unknown. OBJECTIVE To evaluate the contribution of intrasellar pressure (ISP) to headache manifestation by using intraoperative ISP measurement. METHODS The records of 108 patients who had first-time transsphenoidal surgery for pituitary adenoma were reviewed retrospectively. Measurement of intraoperative ISP was undergone using intracranial pressure monitoring sensors and compared with radiological assessment. RESULTS Among 30 patients with headache, 29 (96.7%) presented with significant headache (Headache Impact Score-6, 50 or greater). Intraoperative ISP measurement was conducted successfully in all cases, and revealed higher ISP in patients with headache (35.6 9.2 mm Hg) than in those without headache (15.8 +/- 5.2 mm Hg). The ISP reduction after sella floor decompression was greater in patients with headache than that in patients without headache. In patients with headache, the frequency of invasion into the cavernous sinus or sphenoid sinus was significantly lower, and the diameter of the foramen at the diaphragm sellae was narrower. In addition, intratumoral cyst or hematoma was more common in patients with headache. Postoperatively, headache was either diminished or improved in 28 patients (93.3%). CONCLUSION Headache in patients with pituitary adenomas associated with ISP elevation, results from compromised dural integrity at the sella and intratumoral hemorrhage. The increased stretch force of the sella dura may be a notable etiology of headache in patients with pituitary adenoma.