中等度サイズの内頚動脈瘤に対するretrograde suction & decompressionのススメ

<p>The retrograde suction decompression (RSD) technique is highly effective for direct clipping of large or giant intracranial aneurysms (ANs) in the internal carotid artery (ICA) because it can achieve proximal parent vessel control, improve AN neck visualization by shrinking the AN, and help peel off perforating arteries. The purpose of this study was to describe the technique and surgical results of RSD for middle-sized (<10 mm) AN of the ICA and to recommend the proactive use of RSD for middle-sized ANs of the ICA.</p><p>Materials and Methods: We performed clipping of 354 middle-sized (<10 mm) ANs of the ICA C1-3 portion (ophthalmic and anterior choroidal arteries, posterior communicating artery, and cave) between April 2012 and January 2017. We retrospectively reviewed the clinical data and treatment summaries of 15 cases (4.2%) treated with RSD-assisted clipping and describe the RSD technique. One male and 14 female patients aged 33-80 years (mean, 58.1 years) were included in the study.</p><p>Case Presentation: <Case 1> A 70-year-old-woman with a right internal carotid (IC)-posterior communicating artery AN showed no symptoms. The AN was 8.7 mm in maximum diameter, projected inferiorly, and preoperative computed tomographic angiography (CTA) revealed no atherosclerosis of the parent vessel. However, during operation, we recognized that the intracranial parent vessel was difficult to secure because of its significant atherosclerosis, the aneurysmal wall was fragile, and the AN was located beneath the tentorial edge. Thus, on the basis of the intraoperative findings, we judged the necessity of the RSD technique for safely freeing the perforating arteries from adhesions.</p><p><Case 2> A 42-year-old woman with an anterior wall AN of the left IC C2 portion showed no symptoms. The AN had a maximum diameter of 6.2 mm. Preoperative CTA and magnetic resonance imaging findings indicated that the left optic nerve was displaced superiorly by the AN. Therefore, before attempting an approach to the AN, we decided to practice the RSD technique using the preoperative diagnostic images.</p><p>Results: All the patients except one had a good outcome, and the neurological finding in one patient was the same as that before operation.</p><p>Conclusions: For middle-sized ANs, the RSD technique is a useful procedure to achieve proximal vessel control, to soften and shrink the aneurysmal sac, and to provide a wide and clean operative field that allows for a safe clip placement. During operation, we confidently recommend performing the RSD technique for safely freeing perforating arteries from adhesions to the fragile aneurysmal wall, except for small ANs.</p>