磁共振成像中的金属植入物——危害与成像伪影。

Metallic Implants in MRI - Hazards and Imaging Artifacts.

机构信息

Department for Radiology and Neuroradiology, Molecular Imaging North Competence Center (MOIN CC), Section Biomedical Imaging, University Hospital Schleswig-Holstein - Campus Kiel, Kiel University, Germany.

Department of Radiology and Neuroradiology, University Hospital Schleswig-Holstein - Campus Kiel, Germany.

出版信息

Rofo. 2021 Nov;193(11):1285-1293. doi: 10.1055/a-1460-8566. Epub 2021 May 12.

DOI:10.1055/a-1460-8566

PMID:33979870

Abstract

BACKGROUND

Magnetic resonance imaging (MRI) is an examination method for noninvasive soft tissue imaging without the use of ionizing radiation. Metallic implants, however, may pose a risk for the patient and often result in imaging artifacts. Due to the increasing number of implants, reducing these artifacts has become an important goal. In this review, we describe the risks associated with implants and provide the background on how metal-induced artifacts are formed. We review the literature on methods on how to reduce artifacts and summarize our findings.

METHOD

The literature was searched using PubMed and the keywords "MRI metal artifact reduction", "metallic implants" and "MRI artefacts/artifacts".

RESULTS AND CONCLUSION

The MRI compatibility of implants has to be evaluated individually. To reduce artifacts, two general approaches were found: a) parameter optimization in standard sequences (echo time, slice thickness, bandwidth) and b) specialized sequences, such as VAT, OMAR, WARP, SEMAC and MAVRIC. These methods reduced artifacts and improved image quality, albeit at the cost of a (sometimes significantly) prolonged scan time. New developments in accelerated imaging will likely shorten the scan time of these methods significantly, such that routine use may become feasible.

KEY POINTS

· Metallic implants may pose a risk for patients and often cause artifacts.. · Imaging artifacts can be reduced by parameter optimization or special sequences.. · Metal artifacts are reduced with a lower TE, smaller voxel size, larger matrix, and higher bandwidth.. · SPI, STIR, VAT, SEMAC, MAVRIC, and MAVRIC-SL are specialized MR sequences that can reduce artifacts further..

CITATION FORMAT

· Peschke E, Ulloa P, Jansen O et al. Metallic Implants in MRI - Hazards and Imaging Artifacts. Fortschr Röntgenstr 2021; 193: 1285 - 1293.

摘要

背景

磁共振成像（MRI）是一种无需使用电离辐射即可进行软组织无创成像的检查方法。然而，金属植入物可能会对患者造成风险，并且经常导致成像伪影。由于植入物数量的增加，减少这些伪影已成为一个重要目标。在这篇综述中，我们描述了与植入物相关的风险，并提供了金属诱导伪影形成的背景知识。我们回顾了关于如何减少伪影的文献，并总结了我们的发现。

方法

使用 PubMed 检索文献，并使用关键词“MRI 金属伪影减少”、“金属植入物”和“MRI 伪影/artifact”进行搜索。

结果与结论

必须单独评估植入物的 MRI 兼容性。为了减少伪影，发现了两种一般方法：a）在标准序列中优化参数（回波时间、层厚、带宽）和 b）专门序列，如 VAT、OMAR、WARP、SEMAC 和 MAVRIC。这些方法减少了伪影并提高了图像质量，尽管扫描时间（有时明显）延长。加速成像的新发展可能会大大缩短这些方法的扫描时间，从而使常规使用变得可行。