Kuethe Dean O, Adolphi Natalie L, Fukushima Eiichi
New Mexico Resonance, Albuquerque, NM 87106, USA.
Magn Reson Med. 2007 Jun;57(6):1058-64. doi: 10.1002/mrm.21230.
MR images of laboratory rat lungs that resolve the thin membranes that separate lung lobes are presented. It appears that the capabilities of in vivo small-animal pulmonary MRI may rival those of in vivo small-animal X-ray CT. Free induction decay (FID)-projection imaging was employed with particular attention to the choice of acquisition time. For a given nominal resolution, one obtains optimal point discrimination when the acquisition time T(acq) normalized by the signal decay time constant T(2)(*) is approximately 0.8-0.9, although a better signal-to-noise ratio (SNR) is obtained when this quotient is 1.6. Currently available equipment should be able to even exceed the results presented herein.
本文展示了实验室大鼠肺部的磁共振成像（MR）图像，这些图像能够分辨分隔肺叶的薄膜。体内小动物肺部磁共振成像的能力似乎可与体内小动物X射线计算机断层扫描（X-ray CT）相媲美。采用了自由感应衰减（FID）投影成像，并特别关注采集时间的选择。对于给定的标称分辨率，当采集时间T(acq)除以信号衰减时间常数T(2)(*)的商约为0.8 - 0.9时，可获得最佳的点分辨能力，不过当该商为1.6时能获得更好的信噪比（SNR）。目前可用的设备甚至应该能够超越本文所展示的结果。
