Initial Multicenter Evaluation of a Novel Anchoring Exchange Device: AI-based Quantitative Distal Tip-Motion Analysis

Exchange maneuvers during intracranial angioplasty and stent deployment can cause unintended distal tip motion, potentially leading to vessel injury. We evaluated a novel anchoring exchange device (Medilizer; Medikit, Tokyo, Japan), a 320-cm 0.014-inch wire with a retrievable self-expanding stent at the distal tip, designed to stabilize the distal position during exchange maneuvers and approved for clinical use in Japan.

We compared exchange maneuvers using conventional wires with those using a Medilizer during angioplasty of intracranial stenosis performed at three institutions. Biplane fluoroscopic sequences (frontal and lateral views) were analyzed using an AI-assisted tracking system to quantify the trajectory length of distal tip motion in each view.

Seventeen consecutive procedures (10 conventional wire cases and 7 Medilizer cases) were included. In one Medilizer case, the distal tip was outside the field of view in one projection, which was excluded from the analysis. Consequently, 20 conventional wire and 13 Medilizer views were analyzed. The trajectory length of the distal tip was significantly shorter with the Medilizer than with conventional wires (3.3 ± 1.5 mm vs. 35.9 ± 20.0 mm; p < 0.001), corresponding to an approximately 90% reduction. No adverse events occurred in any of the 17 procedures.

Even in this initial cohort, the magnitude of improvement in distal tip motion strongly suggests clinically meaningful stability advantages of this anchoring exchange device. Furthermore, AI-assisted quantitative evaluation can provide an objective measure of endovascular device performance, warranting further validation studies.