フローダイバーターの適応と留置のコツは？—Pipeline FlexとFREDの違い

Indication and Technical Tips for Flow Diveter Placement:Pipeline and FRED

Point

・Pipeline^TM FlexとFRED^TMで適応血管が異なる．脳底動脈，前大脳動脈および中大脳動脈近位部はFRED^TMのみ適応となる．動脈瘤最大径はいずれも5 mm以上である．

・両端フレアエンドを有するFRED^TMは展開操作が容易であるが，全長展開後の修正はPipeline^TM Flexと比較するとやや難しい．

・硬膜内動脈瘤でのコイル併用は勧められるが，完全に遅発性破裂を予防できるわけではない．

　More than 2000 patients with large aneurysms have been treated with Pipeline^TM Flex since approval in 2015. The indication of Pipeline^TM Flex has expanded according to the PREMIER trial. Moreover, FRED^TM has been approved in 2020 with a wider indication compared to that of Pipeline^TM. Aneurysms with 5 mm or larger of the maximum diameter in the internal carotid artery（ICA）and vertebral artery（VA）are currently indicated for Pipeline^TM. Moreover, the indications for FRED^TM include the proximal anterior cerebral, proximal middle cerebral artery, and basilar artery in addition to the ICA and VA. The use in the acute stage of subarachnoid hemorrhage remains contraindicated for both.

　One should note several specific technical tips for these flow diverters. FRED^TM can be deployed more easily compared to Pipeline^TM due to the large caliper filament and the flare ends. However, FRED^TM is generally resistant to balloon angioplasty after it is fully deployed, most probably because the anchored flare ends disable foreshortening of FRED^TM. Concomitant use of coiling may be recommended for intradural aneurysms to potentially minimize the risk of delayed rupture.