Department of Technology and Health, Italian National Institute of Health, Rome 00161, Italy.
IEEE Trans Biomed Eng. 2010 Aug;57(8):2045-52. doi: 10.1109/TBME.2010.2043102. Epub 2010 Feb 18.
MRI may cause tissue heating in patients implanted with pacemakers (PMs) or cardioverters/defibrillators. As a consequence, these patients are often preventatively excluded from MRI investigations. The issue has been studied for several years now, in order to identify the mechanisms involved in heat generation, and define safety conditions by which MRI may be extended to patients with active implants. In this sense, numerical studies not only widen the range of experimental measurements, but also model a realistic patient's anatomy on which it is possible to study individually the impact of the many parameters involved. In order to obtain reliable results, however, each and every numerical analysis needs to be validated by experimental evidence. Aim of this paper was to design and validate through experimental measurements, an accurate numerical model, which was able to reproduce the thermal effects induced by a birdcage coil on human tissues containing a metal implant, specifically, a PM. The model was then used to compare the right versus left pectoral implantation of a PM, in terms of power deposited at the lead tip. This numerical model may also be used as reference for validating simpler models in terms of computational effort.
MRI 可能会导致植入起搏器 (PM) 或心脏复律除颤器的患者组织发热。因此，这些患者通常被预防性地排除在 MRI 检查之外。为了确定产生热量的机制，并确定可以将 MRI 扩展到带有有源植入物的患者的安全条件，已经对这个问题进行了多年的研究。在这方面，数值研究不仅拓宽了实验测量的范围，而且还对真实患者的解剖结构进行建模，从而可以单独研究涉及的众多参数的影响。然而，为了获得可靠的结果，每个数值分析都需要通过实验证据进行验证。本文的目的是设计并通过实验测量验证一个精确的数值模型，该模型能够再现鸟笼线圈在含有金属植入物（具体为 PM）的人体组织中引起的热效应。然后，该模型用于比较 PM 右侧和左侧胸肌植入的情况，具体为在导联尖端沉积的功率。该数值模型也可以用作在计算工作量方面验证更简单模型的参考。
