[Awake surgery plays a role in neurosurgery and neuroscience]

Awake surgery has been reported to play a role in the safe removal of brain tumors and detection of the functional localization of the cortex or neuronal tracts. In our hospital, from November 2004 to May 2007, we performed awake surgery with continuous tasks in 33 cases of brain tumors within or near the primary motor area (M1). The relationship between the extent of resection and postoperative motor function in awake surgery cases was compared with that in cases of surgery under general anesthesia, which were performed prior to November 2004. In 32 of 33 cases of awake surgery, the final postoperative motor function was either preserved or improved relative to the preoperative levels; however, in 9 of 14 patients who underwent surgery under general anesthesia, deterioration in motor function was noted after surgery. Gross total removal (GTR) was achieved in 20 of 33 cases of awake surgery and in 8 of 14 cases of surgery under general anesthesia, indicating that the extent of resection was similar between awake surgery and surgery under general anesthesia. In most cases of awake surgery, neurological deterioration occurred during internal decompression of the tumors or compression of the normal brain, while surgical manipulation of the tumor margin did not induce neurological deterioration in most cases of surgery under general anesthesia. Moreover, various new findings regarding the function of the cortex or neuronal tract have been reported in awake surgery. We discussed the advantages and future directions of awake surgery. In conclusion, awake surgery plays an important role in neurosurgery and neuroscience.