The Utility of the "LEONIS Mova" Steering Microcatheter in Flow Diverter Placement

Objective: LEONIS Mova (SB-KAWASUMI LABORATORIES, Kanagawa, Japan, hereinafter called LEONIS Mova) is a steerable microcatheter (MC) that enables angle adjustment of the catheter tip using a hand-operated dial. LEONIS Mova may be useful for flow diverter placement when access to the distal parent artery with a conventional MC and microguidewire (MGW) is considered difficult or impossible. Here, we report three such cases encountered during flow diverter placement in large and giant internal carotid artery aneurysms.

Case presentation: In Case 1, a strong S-shaped curve was observed in the proximal parent artery of a giant cerebral aneurysm, and the luminal structure of the parent artery was lost within the aneurysm. It was anticipated that the distal side of the parent artery would be difficult to access with conventional MC and MGW. By adjusting the tip of the LEONIS Mova toward the aneurysm outlet beyond the S-shaped curve, it was possible to induce the MGW to secure the distal parent artery easily. In Case 2, the inflow and outflow axes of the parent artery were completely misaligned at the site of the aneurysm, and stenosis was present in the distal parent artery. Firmly bending the catheter tip increased accommodation for the catheter, enabling the induction of an MGW to access the distal parent artery without kicking back. In Case 3, the lesion extended from the cavernous portion to the petrosal portion; however, by adjusting the tip of the LEONIS Mova toward the aneurysm outlet, it was possible to induce the MGW to secure the distal parent artery easily. In each case, the LEONIS Mova enabled more secure and prompt access to the parent artery than anticipated and facilitated flow diverter placement.

Conclusion: Encountering difficult-to-access lesions is one reason endovascular treatment may be unsuccessful. The LEONIS Mova is an excellent device that can overcome this obstacle, and its utility in certain applications should be recognized.