未破裂脳動脈瘤に対するkeyhole clipping術中の内視鏡支援の有用性について

抄録

We have accumulated surgical experience with keyhole clipping for small anterior circulation aneurysms. Recently, we used not only motor evoked potentials (MEP) and indocyanine green video-angiography (ICG) but also a rigid scope during surgery to compensate for the narrow working angle, which is a major disadvantage of keyhole surgery.
Between April 2013 and August 2014, we performed endoscope-assisted keyhole clipping for 27 aneurysms in 24 consecutive patients. A supraorbital keyhole for internal cerebral artery aneurysms (IC An.), lateral supraorbital keyhole for anterior communicating artery aneurysms (A-com An.), and pterional keyhole for middle cerebral artery aneurysms (MC An.) were conducted. The optimal keyhole and patient's head position were planned for each individual with a preoperative simulation system using three-dimensional computed tomography angiography. A rigid scope (EndoArm, OLYMPUS) was used to observe the aneurysms before and after clipping.
Of 27 aneurysms in 24 operations, supraorbital keyhole, lateral supraorbital keyhole, and pterional keyhole were used for seven, nine (including one case of A-com An. and IC-posterior communicating artery An.), and eight (including two cases of multiple MC An.) operations, respectively. The endoscope provided a favorable enhancement of the visual field. No adverse effects were observed. All of the aneurysms but one IC An. (96.3%) were inspected using endoscopy both before and after clipping. The post-clipping inspection revealed two cases (7.7%) with incomplete clipping of the A-com An. We used an additional clip in one case and rearranged the clip in the other one. In one case (3.8%) of MC An., clip rearrangement after endoscopic evaluation was necessary because of branch occlusion. Although the 0 and 30-degree rigid scopes were very useful, the 70-degree scope was too difficult to guide to the aneurysms for observation.
Endoscopic inspection before and after clipping during keyhole surgery might be an effective and safe method to increase treatment quality. Although a larger study is needed to support these findings, the likelihood of unexpected results could be decreased with the combined use of an endoscope, Doppler, ICG, and MEP.