Luoma E K, Raininko R, Nummi P J, Luukkonen R, Manninen H I, Riihimäki H A
Finnish Institute of Occupational Health, Helsinki, Finland.
Neuroradiology. 1997 Oct;39(10):728-32. doi: 10.1007/s002340050496.
The suitability of the cerebrospinal fluid (CSF) in the lumbosacral dural sac as an internal signal-intensity reference was studied on magnetic resonance imaging (MRI) of the lumbar spine using a surface coil and motion artefact suppression technique. A signal-intensity reference is needed when signal is compared between images, studies or subjects. Homogeneity of the CSF was estimated visually on T2-weighted images of 60 subjects at 1.5 T and of another 60 subjects at 0.1 T. Spines with a severely narrowed dural sac or marked scoliosis were excluded from the study to avoid partial volume effect. CSF was homogeneous in 82% and 73% of the examinations at 1.5 T and 0.1 T, respectively. The type and location of the local inhomogeneities did not relate to local narrowings of the dural sac. The signal intensity of CSF was measured in 108 examinations at 0.1 T after correcting the spatially-dependent signal-intensity non-uniformities with a phantom-based method. The signal-intensity difference between the CSF in the upper and lower lumbar dural sac was less than 10% in 73% of the examinations. The CSF in the lumbosacral dural sac can be a useful signal-intensity reference for estimation of the signal of the adjacent structures in patients without severe narrowing of the dural sac or marked scoliosis. It may contribute to assessing spinal disease processes.
采用表面线圈和运动伪影抑制技术，在腰椎磁共振成像（MRI）上研究了腰骶部硬脊膜囊内脑脊液（CSF）作为内部信号强度参考的适用性。在比较图像、研究或受试者之间的信号时，需要信号强度参考。在1.5T下对60名受试者以及在0.1T下对另外60名受试者的T2加权图像上，通过视觉评估脑脊液的均匀性。将硬脊膜囊严重狭窄或明显脊柱侧弯的脊柱排除在研究之外，以避免部分容积效应。在1.5T和0.1T的检查中，脑脊液均匀的分别占82%和73%。局部不均匀性的类型和位置与硬脊膜囊的局部狭窄无关。在0.1T下的108次检查中，采用基于体模的方法校正空间相关的信号强度不均匀性后，测量了脑脊液的信号强度。在73%的检查中，腰骶部硬脊膜囊内上下段脑脊液的信号强度差异小于10%。对于硬脊膜囊无严重狭窄或明显脊柱侧弯的患者，腰骶部硬脊膜囊内的脑脊液可作为评估相邻结构信号的有用信号强度参考。它可能有助于评估脊柱疾病进程。
