Double stent-retriever (SR) technique: a novel mechanical thrombectomy technique to facilitate the device-clot interaction for refractory acute large vessel occlusions.

Abstract Background Mechanical thrombectomy has become the standard treatment for acute ischemic stroke caused by large vessel occlusion; however, refractory occlusions still exist despite various thrombectomy procedures. The double stent-retriever (SR) technique, which utilizes not a single, but two SRs simultaneously at the occlusion, can be useful for such refractory occlusions. Methods We described two cases of refractory acute cerebral occlusion despite the use of conventional thrombectomy procedures, which were both treated with the double SR technique. To discuss the technical aspects of how this easy-to-perform technique facilitates the device-clot interaction, we also evaluated radiographic findings of the SR’s strut during the procedure. Results In both cases, conventional thrombectomy procedures, including an SR alone, an aspiration catheter alone, and combined use of the SR and aspiration catheter failed to recanalize the occlusion. Then, the double SR technique was performed with the stent-in-stent method in one patient and the parallel stent method in the other patient. One pass of this technique retrieved hard clots and successfully recanalized the refractory occlusion in both cases. Intraprocedural radiographical images of these cases showed that the degree of stent expansion improved after deployment of the second SR compared with the first one. Conclusions Our radiographical findings suggested that adding one more SR facilitates the device-clot interaction at the occlusion site. The double SR technique may be an easy-to-perform thrombectomy technique to improve the clot-capturing ability for the management of refractory acute cerebral artery occlusions.