[Indications and Usage of New Devices such as PulseRider and W-EB for Bifurcation-type Aneurysms]

Bifurcation-type aneurysms located at the basilar tip, anterior communicating artery, and middle cerebral artery are difficult to treat by endovascular coil embolization. One reason for this is that it is impossible to completely cover the aneurysm neck with a single stent because of the branching of two large vessels at the location. Moreover, the parent artery blood flows directly into the aneurysm dome and induces recanalization of the placed coils. In 2020, new devices for bifurcation aneurysms, such as PulseRider and W-EB, were approved in Japan. PulseRider has been in use since September, and W-EB is expected to be available by the end of the year. PulseRider has unique leaflets, which easily cover the broad neck of bifurcation aneurysms and prevent the coil from protruding into the parent artery. W-EB is a nitinol self-expandable mesh ball implant that can prevent blood flow into the aneurysm and subsequent induced thrombosis by deployment in the aneurysm sac. Although we do not yet completely know the features and advantages of either, we expect these two new devices to improve endovascular treatment of bifurcation-type aneurysms that thus far have been difficult to treat.