The arachnoidea between the superficial sylvian vein and the temporal lobe is incised, and the bridging veins flowing from the temporal lobe to the superficial sylvian vein and those at the temporal tip are cut. Thus, the temporal lobe is separated from the superficial sylvian vein. The anterior temporal artery is separated from the temporal lobe. These treatments increase the mobility of the temporal lobe. The sylvian fissure is widely opened by compression of the temporal lobe with a spatula placed under the anterior temporal artery. This approach provides good access to the lesions in the interpeduncular cistern.
