Intraoperative Pituitary Adenoma Identification Using Intraoperative Spectroscopic System

The search continues to remove the guesswork out of distinguishing normal from abnormal tissue in the management of intracranial tumors. 5-anino-levulenic acid (5ALA) is a precursor in the synthesis of heme. Each living cell of the human body metabolizes 5ALA along a set pathway to heme-producing protoporphyrin IX (ppIX) along the way. As the transformation of ppIX to heme is blocked in tumor cells, it accumulates in these cells in vast quantities. ppIX is naturally photoactive, absorbs blue light energy, and transmits it back in the red spectrum. We investigated the use of dedicated ppIX-spectroscopic system to detect ppIX in 17 consecutive patients with pituitary adenomas; 8 null cell, 4 GH, 3 ACTH, and 2 FSH. 5ALA was given orally at 20 mg per kg of body weight, 3 hours prior to anesthesia. Sixteen adenomas were positive, making this technology valuable in locating the exact site of microadenomas during surgery.