Thomas M A, Huda A, Guze B, Curran J, Bugbee M, Fairbanks L, Ke Y, Oshiro T, Martin P, Fawzy F
Department of Radiological Sciences, UCLA School of Medicine, University of California, Los Angeles 90095, USA.
AJR Am J Roentgenol. 1998 Oct;171(4):1123-30. doi: 10.2214/ajr.171.4.9763008.
Our objective was to assess the metabolite levels (myo-inositol [ml], choline [Cho], creatine [Cr], glutamate or glutamine [Glx], and N-acetyl-L-aspartate [NAA]) visible on 1H MR spectroscopy in patients with subclinical and mild hepatic encephalopathy before and after liver transplantation and to correlate these data with the results of neuropsychiatric tests and related clinical findings.
A stimulated-echo sequence was used to localize a single voxel in the parietal region. Seventeen patients and 13 healthy volunteers were investigated. Nine of the 17 patients also were investigated after liver transplantation. A battery of neuropsychologic tests also was administered to patients to assess frontal, memory, and motor functions.
Before liver transplantation, significant reductions in mI:Cr (51%) and Cho:Cr (11%) and a significant increase in Glx:Cr (20%) were observed in patients compared with the respective ratios in healthy subjects. Patients also were significantly impaired on neuropsychologic tests measuring frontal and motor performance, but not memory. Impairment on the frontal index showed a significant correlation with mI:Cr levels; likewise, performance on the motor index showed a significant correlation with serum ammonia levels before transplantation. MR spectroscopy after liver transplantation showed changes in the metabolite ratios compared with the pretransplantation status. Even though the Glx:Cr ratios decreased after transplantation, the mI:Cr ratio remained lower than those of healthy subjects.
The relationship of changes in the metabolite ratios recorded from a voxel in the posteromedial parietal lobe to the neuropsychologic findings before and after liver transplantation is a major finding.
我们的目的是评估肝移植前后亚临床和轻度肝性脑病患者1H磁共振波谱可见的代谢物水平（肌醇[ml]、胆碱[Cho]、肌酸[Cr]、谷氨酸或谷氨酰胺[Glx]以及N-乙酰-L-天门冬氨酸[NAA]），并将这些数据与神经心理测试结果及相关临床发现进行关联。
采用刺激回波序列在顶叶区域定位单个体素。对17例患者和13名健康志愿者进行了研究。17例患者中有9例在肝移植后也进行了研究。还对患者进行了一系列神经心理学测试，以评估额叶、记忆和运动功能。
与健康受试者的相应比值相比，肝移植前患者的mI:Cr（51%）和Cho:Cr（11%）显著降低，Glx:Cr（20%）显著升高。患者在测量额叶和运动表现的神经心理学测试中也有显著受损，但记忆方面未受损。额叶指数的受损与mI:Cr水平显著相关；同样，运动指数的表现与移植前的血清氨水平显著相关。肝移植后的磁共振波谱显示代谢物比值与移植前状态相比有变化。尽管移植后Glx:Cr比值下降，但mI:Cr比值仍低于健康受试者。
从顶叶后内侧叶体素记录的代谢物比值变化与肝移植前后神经心理学发现之间的关系是一项主要发现。
