Vega Sergio Ruiz, Mesa Juan C, Blanquer Coral, Barinaga Cristian, Cabaniss Tanner L, Enriquez Angel, Bohnstedt Bradley N, Lee Chung-Hao, Lee Hyowon
Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907, USA.
Center for Implantable Devices, Purdue University, West Lafayette, IN, 47907, USA.
Ann Biomed Eng. 2025 Aug 3. doi: 10.1007/s10439-025-03816-w.
Intracranial aneurysms (ICAs) pose a serious clinical risk due to their potential for rupture, leading to subarachnoid hemorrhage, high morbidity, and mortality. This study aims to develop a proof-of-concept device for the targeted delivery of shape memory polymers (SMPs)-based embolic devices to improve aneurysm occlusion and reduce recurrence.
A novel system was designed combining a radial compression fixture and an electronic device for Joule heating and electrolytic detachment (ED). Three SMP geometries (5, 6.5 mm spherical, and patient-specific) were evaluated for the shape recovery and thermal responses. In-vitro testing was performed using 6.5 mm and patient-specific geometries in PDMS aneurysm phantoms under physiological relevant conditions utilizing ovine blood.
Controlled activation of the SMPs at currents of 400 mA achieved reproducible shape recovery ratios (SRRs) up to 75.71%, with detachment occurring at < 100 mA. Surface temperatures remained below 45 °C. In-vitro deployment resulted in aneurysm sac occlusion of 90.32% (patient-specific) and 94.12% (idealized), without evidence of thermal damage or gas accumulation. Flow visualization confirmed reduced bubble entry into the aneurysm sac post-deployment.
This study demonstrates the feasibility of a targeted delivery system for patient-specific ICA treatment using SMPs. While further refinement and in-vivo validation are required, these findings highlight the potential of SMPs as durable embolization devices capable of conforming to complex aneurysm geometries and providing more effective occlusion compared to current methods.
颅内动脉瘤（ICAs）因其有破裂的潜在风险，会导致蛛网膜下腔出血、高发病率和死亡率，从而带来严重的临床风险。本研究旨在开发一种概念验证装置，用于靶向递送基于形状记忆聚合物（SMPs）的栓塞装置，以改善动脉瘤闭塞并减少复发。
设计了一种新颖的系统，该系统结合了径向压缩固定装置以及用于焦耳加热和电解分离（ED）的电子设备。评估了三种SMP几何形状（5毫米、6.5毫米球形以及患者特异性的）的形状恢复和热响应。在生理相关条件下，使用羊血，在聚二甲基硅氧烷（PDMS）动脉瘤模型中，对6.5毫米和患者特异性几何形状进行体外测试。
在400毫安电流下对SMPs进行可控激活，可实现高达75.71%的可重复形状恢复率（SRRs），在小于100毫安时发生分离。表面温度保持在45°C以下。体外部署导致动脉瘤囊闭塞率达到90.32%（患者特异性的）和94.12%（理想化），没有热损伤或气体积聚的迹象。流动可视化证实部署后进入动脉瘤囊的气泡减少。
本研究证明了使用SMPs进行患者特异性ICA治疗的靶向递送系统的可行性。虽然需要进一步完善和体内验证，但这些发现突出了SMPs作为耐用栓塞装置的潜力，与当前方法相比，其能够贴合复杂的动脉瘤几何形状并提供更有效的闭塞。
