Radio-guided brain tumorectomy using a gamma detecting probe and a mobile solid-state gamma camera

Abstract

Background We herein report a technique to distinguish brain tumors from normal brain tissue during surgery using a gamma probe and a solid-state mobile gamma camera after 99mTc-hexakis-2-methoxy-isobutyl-isonitrile ( 99mTc-MIBI) is administered to patients immediately before operation. Methods We examined 13 patients with brain tumors. Before the operation, 99mTc-MIBI single photon emission computed tomography (SPECT) was performed to assess accumulation in the tumors. On the day of the operation, 99mTc-MIBI was administered intravenously and craniotomy for tumor resection was performed. During the operation, the tumor was localized with a gamma probe and preremoval scintigraphy images were taken with a mobile gamma camera. After tumor resection was completed, residual tumors were confirmed using it again. We compared accumulation found in the preoperative SPECT images and intraoperative scintigraphy images, performed a histologic examination of adjacent tissues, and measured the dose the personnel was exposed to per operation. Results In all patients, tumors were confirmed by a gamma probe and scintigraphy during the operation. Intraoperative accumulation in tumors was significantly related to accumulation found in the preoperative 99mTc-MIBI SPECT images. In 9 out of 13 patients, accumulation disappeared in the postremoval scintigraphy images, and no tumor tissue was found by histologic examination. Residual tumor tissue was found in 4 patients. Average exposure of the personnel per operation was 22.9 ± 4.0 μSv. Conclusion Resection of brain tumors with a gamma probe and a mobile gamma camera was very useful since the area to be removed was easily identified and residual tumors could be detected.