Nakagawa Kanji, Toyota Shingo, Shimizu Takeshi, Murakami Tomoaki, Taki Takuyu
Department of Neurosurgery, Kansai Rosai Hospital, Amagaski, Hyogo, Japan.
Asian J Neurosurg. 2022 Aug 25;17(2):337-341. doi: 10.1055/s-0042-1750386. eCollection 2022 Jun.
Although Onyx is approved as an embolic material for arteriovenous malformation (AVM) and dural arteriovenous fistula (dAVF), metal artifacts due to Onyx on CT remain problematic. We report the feasibility of a metal artifact reduction (MAR) algorithm on CT angiography (CTA) in the planning of direct surgery of dAVF after transarterial Onyx embolization. A 45-year-old male patient presented with right pulsatile tinnitus, and cerebral angiography demonstrated right tentorial dAVF. As the dAVF had not completely disappeared even after Onyx transarterial embolization, we planned direct surgery. Evaluation of the lesion was difficult on normal preoperative CTA because of Onyx artifacts, but CTA using MAR enabled a detailed planning of direct surgery. Direct surgery was performed through right retrosigmoid craniotomy. Referencing CTA using MAR, we identified the draining veins originating from the main drainer, which were coagulated and cut, achieving complete occlusion of the dAVF. His symptoms disappeared with no postoperative complications. CT angiography using MAR was useful for planning direct surgery after Onyx embolization. As the incidence of direct surgery after transarterial Onyx embolization for AVM or dAVF is increasing, MAR on CTA will become more important.
尽管Onyx被批准作为一种用于动静脉畸形（AVM）和硬脑膜动静脉瘘（dAVF）的栓塞材料，但Onyx在CT上产生的金属伪影仍然是个问题。我们报告了在经动脉Onyx栓塞后直接手术治疗dAVF的规划中，CT血管造影（CTA）上的金属伪影减少（MAR）算法的可行性。一名45岁男性患者出现右侧搏动性耳鸣，脑血管造影显示右侧小脑幕dAVF。由于即使在经动脉Onyx栓塞后dAVF仍未完全消失，我们计划进行直接手术。由于Onyx伪影，术前常规CTA对病变的评估很困难，但使用MAR的CTA能够对直接手术进行详细规划。通过右侧乙状窦后开颅术进行直接手术。参考使用MAR的CTA，我们识别出起源于主要引流静脉的引流静脉，对其进行凝固和切断，实现了dAVF的完全闭塞。他的症状消失，无术后并发症。使用MAR的CT血管造影对经动脉Onyx栓塞后的直接手术规划很有用。随着经动脉Onyx栓塞治疗AVM或dAVF后直接手术的发生率增加，CTA上的MAR将变得更加重要。
