Silva Nuno P, Amin Bilal, Dunne Eoghan, O'Halloran Martin, Elahi Adnan
Translational Medical Device Lab, University of Galway, Galway, H91 TK33, Ireland.
Electrical and Electronic Engineering, University of Galway, Galway, H91 TK33, Ireland.
Cardiovasc Eng Technol. 2025 Feb;16(1):1-19. doi: 10.1007/s13239-024-00753-y. Epub 2024 Oct 7.
An abdominal aortic aneurysm (AAA) is a dilation of the aorta over its normal diameter (> 3 cm). The minimally invasive treatment adopted uses a stent graft to be deployed into the aneurysm by a catheter to flow blood through it. However, this approach demands frequent monitoring using imaging modalities that involve radiation and contrast agents. Moreover, the multiple follow-ups are expensive, time-consuming, and resource-demanding for healthcare systems. This study proposes a novel wireless implantable medical sensor (WIMS) to measure the aneurysm growth after the endovascular repair.
The proposed sensor is composed of a Z-shaped inductor, similar to a stent ring. The proposed design of the sensor is explored by investigating the inductance, resistance, and quality factor of different possible geometries related to a Z-shaped configuration, such as the height and number of struts. The study is conducted through a combination of numerical simulations and experimental tests, with the assessment being carried out at a frequency of 13.56 MHz.
The results show that a higher number of struts result in higher values of inductance and resistance. On the other hand, the increase in the number of struts decreases the quality factor of the Z-shaped inductor due to the presence of high resistance from the inductor. Moreover, it is observed that the influence of the number of struts present in the Z-shaped inductor tends to decrease for larger radii.
The numerical and experimental evaluation concludes the ability of the proposed sensor to measure the size of the aneurysm.
腹主动脉瘤（AAA）是主动脉直径超过其正常直径（>3厘米）的扩张。所采用的微创治疗方法是使用支架移植物，通过导管将其部署到动脉瘤中，使血液流经该移植物。然而，这种方法需要使用涉及辐射和造影剂的成像方式进行频繁监测。此外，多次随访对于医疗系统来说成本高昂、耗时且需要大量资源。本研究提出一种新型无线可植入医疗传感器（WIMS），用于测量血管内修复术后动脉瘤的生长情况。
所提出的传感器由一个Z形电感组成，类似于一个支架环。通过研究与Z形配置相关的不同可能几何形状（如支柱的高度和数量）的电感、电阻和品质因数，来探索该传感器的设计方案。该研究通过数值模拟和实验测试相结合的方式进行，评估频率为13.56兆赫兹。
结果表明，支柱数量越多，电感和电阻值越高。另一方面，由于电感存在高电阻，支柱数量的增加会降低Z形电感的品质因数。此外，观察到对于较大半径，Z形电感中支柱数量的影响趋于减小。
数值和实验评估得出所提出的传感器能够测量动脉瘤大小的结论。
