Kauczor H U, Chen X J, van Beek E J, Schreiber W G
Dept of Radiology, Johannes Gutenberg-Universitaet Mainz, Germany.
Eur Respir J. 2001 May;17(5):1008-23. doi: 10.1183/09031936.01.17510080.
Over the past few years, magnetic resonance imaging (MRI) has emerged as an important instrument for functional ventilation imaging. The aim of this review is to summarize established clinical methods and emerging techniques for research and clinical arenas. Before the advent of MRI, chest radiography and computed tomography (CT) dominated morphological lung imaging, while functional ventilation imaging was accomplished with scintigraphy. Initially, MRI was not used for morphological lung imaging often, due to technical and physical limitations. However, recent developments have considerably improved anatomical MRI, as well as advanced new techniques in functional ventilation imaging, such as inhaled contrast aerosols, oxygen, hyperpolarized noble gases (Helium-3, Xenon-129), and fluorinated gases (sulphur-hexafluoride). Straightforward images demonstrating homogeneity of ventilation and determining ventilated lung volumes can be obtained. Furthermore, new image-derived functional parameters are measurable, such as airspace size, regional oxygen partial pressure, and analysis of ventilation distribution and ventilation/perfusion ratios. There are several advantages to using MRI: lack of radiation, high spatial and temporal resolution and a broad range of functional information. The MRI technique applied in patients with chronic obstructive pulmonary disease, emphysema, cystic fibrosis, asthma, and bronchiolitis obliterans, may yield a higher sensitivity in the detection of ventilation defects than ventilation scintigraphy, CT or standard pulmonary function tests. The next step will be to define the threshold between physiological variation and pathological defects. Using complementary strategies, radiologists will have the tools to characterize the impairment of lung function and to improve specificity.
在过去几年中，磁共振成像（MRI）已成为功能通气成像的重要手段。本综述的目的是总结已确立的临床方法以及用于研究和临床领域的新兴技术。在MRI出现之前，胸部X线摄影和计算机断层扫描（CT）主导着肺部形态学成像，而功能通气成像则通过闪烁扫描法完成。最初，由于技术和物理限制，MRI并不常用于肺部形态学成像。然而，最近的发展显著改善了解剖学MRI，以及功能通气成像中的先进新技术，如吸入性对比气雾剂、氧气、超极化惰性气体（氦-3、氙-129）和氟化气体（六氟化硫）。可以获得显示通气均匀性和确定通气肺容积的直观图像。此外，新的图像衍生功能参数是可测量的，如气腔大小、局部氧分压以及通气分布和通气/灌注比的分析。使用MRI有几个优点：无辐射、高空间和时间分辨率以及广泛的功能信息。应用于慢性阻塞性肺疾病、肺气肿、囊性纤维化、哮喘和闭塞性细支气管炎患者的MRI技术，在检测通气缺陷方面可能比通气闪烁扫描、CT或标准肺功能测试具有更高的敏感性。下一步将是确定生理变异和病理缺陷之间的阈值。通过采用互补策略，放射科医生将拥有表征肺功能损害并提高特异性所需的工具。
