Department of Otorhinolaryngology - Head and Neck Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto city, Nagano 390-8621, Japan.
Department of Otorhinolaryngology - Head and Neck Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto city, Nagano 390-8621, Japan.
Auris Nasus Larynx. 2023 Dec;50(6):874-879. doi: 10.1016/j.anl.2023.04.001. Epub 2023 Apr 17.
Cochlear implants (CIs) were noncompatible with magnetic resonance imaging (MRI) initially; however, recently, implants have become available that are compatible with MRI without the need for magnet removal or bandage fixation. The images produced by MRI scans are sometimes deteriorated by artifacts and are not clinically useful. In this study, we discussed the size differences of such artifacts with respect to the imaging modality and sequences with their clinical validity.
We performed a head MRI, using a head bandage and without magnet removal in five patients who underwent cochlear implantation at our department and analyzed the MRI findings.
Without magnet removal, diffusion-weighted images and T2 star-weighted images had larger artifacts and less useful images. T1-weighted images, T2-weighted images (T2WIs), T2-weighted fluid-attenuated inversion recovery (T2-FLAIR) images, and heavy T2WIs could evaluate the unimplanted side and middle of the head but had limited applicability on the CI side.
The characteristic features of MRI scan images vary with the method used as well as with the sequence, suggesting that the choice of MRI is largely determined on the basis of clinical feasibility and the requirement. Accordingly, we need to judge well in advance of imaging whether the images would be clinically relevant.
最初，耳蜗植入物（CI）与磁共振成像（MRI）不兼容；然而，最近，出现了可兼容 MRI 而无需移除磁铁或绷带固定的植入物。MRI 扫描产生的图像有时会因伪影而恶化，并且在临床上没有用处。在本研究中，我们讨论了这些伪影相对于成像方式和序列的大小差异及其临床有效性。
我们对在我科接受耳蜗植入的五名患者进行了头部 MRI 检查，使用头部绷带且不取出磁铁，并对 MRI 检查结果进行了分析。
不取出磁铁时，扩散加权图像和 T2 星加权图像的伪影较大，图像的有用性较低。T1 加权图像、T2 加权图像（T2WI）、T2 加权液体衰减反转恢复（T2-FLAIR）图像和重 T2WI 可以评估未植入侧和头部中间部分，但在 CI 侧的适用性有限。
MRI 扫描图像的特征随使用的方法和序列而变化，这表明 MRI 的选择在很大程度上取决于临床可行性和需求。因此，我们需要在成像前提前判断图像是否具有临床相关性。
