Geissler A, Lock G, Fründ R, Held P, Hollerbach S, Andus T, Schölmerich J, Feuerbach S, Holstege A
Department of Radiology, University of Regensburg, Germany.
Hepatology. 1997 Jan;25(1):48-54. doi: 10.1053/jhep.1997.v25.pm0008985263.
Hepatic encephalopathy is a common problem in cirrhosis. The pathogenesis of this complication of advanced liver disease still remains unclear. Magnetic resonance spectroscopy was used to assess prospectively cerebral metabolism in 51 patients with histologically proven cirrhosis (Child-Pugh classes A, B, and C, 18, 18, and 15, respectively) and 36 healthy volunteers. According to the results of psychometric tests, overt hepatic encephalopathy, subclinical encephalopathy, and no encephalopathy were found in 14, 21, and 16 patients, respectively. Myoinositol/creatine ratios in gray (.36 +/- .17) and white (.35 +/- .22) matter voxel were reduced significantly (P < .0001) in cirrhotic patients compared with healthy volunteers (gray matter, .51 +/- .11; white matter, .64 +/- .16). In addition, patients showed a significant reduction (P = .024) in white matter choline/creatine ratio (.77 +/- .27) compared with controls (.92 +/- .25), and glutamine/glutamate level was elevated in cirrhotic patients compared with controls (gray matter, P < .0001; white matter, P = .036). Changes in cerebral myoinositol and glutamine/glutamate levels correlated significantly with the severity of hepatic encephalopathy (P < .0001). However, these metabolic alterations were also detected in patients without hepatic encephalopathy (normal psychometric test results). N-acetyl aspartate/creatine ratios did not differ between patients and controls. Magnetic resonance imaging detected bright basal ganglia in 37 patients, which correlated significantly with portal-systemic shunting and elevation of glutamine/glutamate, but not with the degree of hepatic encephalopathy. In conclusion, magnetic resonance imaging and spectroscopy showed that alterations of cerebral metabolism are common in patients with cirrhosis, even without evidence of clinical or subclinical hepatic encephalopathy.
肝性脑病是肝硬化患者常见的问题。这种晚期肝病并发症的发病机制仍不清楚。本研究采用磁共振波谱前瞻性评估了51例经组织学证实为肝硬化的患者(Child-Pugh分级A、B、C级分别为18例、18例和15例)及36名健康志愿者的脑代谢情况。根据心理测量测试结果,分别有14例、21例和16例患者存在显性肝性脑病、亚临床肝性脑病和无肝性脑病。与健康志愿者相比,肝硬化患者灰质(0.36±0.17)和白质(0.35±0.22)体素中的肌醇/肌酸比值显著降低(P<0.0001)(健康志愿者灰质为0.51±0.11,白质为0.64±0.16)。此外,与对照组相比,患者白质胆碱/肌酸比值显著降低(P = 0.024)(患者为0.77±0.27,对照组为0.92±0.25),肝硬化患者谷氨酰胺/谷氨酸水平高于对照组(灰质,P<0.0001;白质,P = 0.036)。脑肌醇和谷氨酰胺/谷氨酸水平的变化与肝性脑病的严重程度显著相关(P<0.0001)。然而,在无肝性脑病(心理测量测试结果正常)的患者中也检测到了这些代谢改变。患者与对照组之间的N-乙酰天门冬氨酸/肌酸比值无差异。磁共振成像在37例患者中检测到基底节区信号增强,这与门体分流及谷氨酰胺/谷氨酸升高显著相关,但与肝性脑病的程度无关。总之,磁共振成像和波谱显示,肝硬化患者即使没有临床或亚临床肝性脑病的证据,脑代谢改变也很常见。