Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, 110029, India.
Indian J Pediatr. 2019 Sep;86(9):842-853. doi: 10.1007/s12098-018-02852-w. Epub 2019 Feb 5.
Chest radiographs and CT scans have been the cornerstone of pulmonary imaging given their advantages of being rapid and easily available techniques. However, a significant concern with their use in the pediatric population is the associated ionisation radiation. The use of magnetic resonance imaging (MRI) in pulmonary imaging has lagged behind its adoption in other organ systems. Previously, the lung parenchyma was considered difficult to evaluate by magnetic resonance due to low proton density in the pulmonary tissue, susceptibility artefacts within the lungs, and respiratory motion artefacts. However, in recent years, there have been a multitude of technical advancements to overcome these limitations. MRI can be an excellent radiation-free alternative in patients who require protracted follow-up like in cases such as cystic fibrosis, complicated pneumonias, tuberculosis and mediastinal neoplasms. An added advantage of MRI is that it can provide functional information in addition to the structural information provided by traditional imaging techniques. One of the major reasons of limited use of MRI despite its established utility is the lack of clarity regarding its indications, and a paucity of data on tailored MRI protocols customised to clinical needs. This article aims to review the basic MRI techniques, indications and terminologies used in chest imaging, with special emphasis on imaging findings of common pathologies in the pediatric population.
鉴于胸部 X 光片和 CT 扫描具有快速和易于获取的优势,它们一直是肺部成像的基石。然而,在儿科人群中使用这些方法的一个主要问题是与之相关的电离辐射。磁共振成像(MRI)在肺部成像中的应用落后于其在其他器官系统中的应用。以前,由于肺部组织中的质子密度低、肺部内的磁化率伪影和呼吸运动伪影,磁共振成像难以评估肺部实质。然而,近年来,已经有许多技术进步来克服这些限制。对于需要长期随访的患者,例如囊性纤维化、复杂肺炎、结核病和纵隔肿瘤患者,MRI 可以作为一种极好的无辐射替代方法。MRI 的一个额外优势是它除了提供传统成像技术提供的结构信息外,还可以提供功能信息。尽管 MRI 已经确立了其效用,但限制其使用的主要原因之一是其适应症不明确,以及针对临床需求定制的 MRI 协议的数据不足。本文旨在回顾胸部成像中使用的基本 MRI 技术、适应症和术语,特别强调儿科人群中常见病变的影像学表现。