Shen W C, Lee S K, Ko K Z
Department of Radiology, Taichung Veterans General Hospital.
Zhonghua Yi Xue Za Zhi (Taipei). 1991 Nov;48(5):369-75.
It has been well documented that high field magnetic resonance imaging can detect the location of physiological deposition of iron in the brain; such as in the globus pallidus, red nucleus, substantia nigra and dentate nucleus. The areas depict very low signal intensity in the long TR and the long TE imaging (T2 weighted image), because the iron enhances the T2 relaxation time. The purpose of this study was to determine the detectability of iron deposition in the brain by our 1.0-T high field MR, compared with 1.5-T MR which was used by most authors. We collected 160 MRI cases of the brain, and observed also signal void areas in the basal ganglion, brainstem or cerebellum. Our T2WI was TR 2000-3000 msec, TE 80-120 msec. We found that the 1.0-T MR clearly detected the iron deposition in the globus pallidus, red nucleus, substantia nigra and dentate nucleus of adults, with additional areas in the putamen and caudate nucleus of aged people. Shortcomings of the 1.0-T MRI for detecting iron deposition include: the margin of iron deposition was not very sharp in some cases, and for children under detectability was markedly inferior to the 1.5-T MR.
已有充分文献证明,高场磁共振成像能够检测大脑中铁的生理沉积位置,如苍白球、红核、黑质和齿状核。在长TR和长TE成像(T2加权图像)中,这些区域呈现出非常低的信号强度,因为铁会延长T2弛豫时间。本研究的目的是与大多数作者使用的1.5-T磁共振成像相比,确定我们的1.0-T高场磁共振成像对大脑中铁沉积的检测能力。我们收集了160例脑部磁共振成像病例,并观察了基底神经节、脑干或小脑中的信号缺失区域。我们的T2WI序列参数为TR 2000 - 3000毫秒,TE 80 - 120毫秒。我们发现,1.0-T磁共振成像能够清晰检测出成人苍白球、红核、黑质和齿状核中的铁沉积,在老年人的壳核和尾状核中也发现了额外的沉积区域。1.0-T磁共振成像检测铁沉积的缺点包括:在某些情况下,铁沉积的边界不是很清晰,并且对于儿童,其检测能力明显低于1.5-T磁共振成像。