Yazgan Yusuf, Narin Yavuz, Demirturk Levent, Saracoglu Mehmet, Ercan Mustafa, Akyatan Nevzat, Dalkanat Nagehan, Ozel A Melih, Cetin Mesut
Departments of Gastroenterology, Nuclear Medicine, Neurology, and Psychiatry, Gulhane Military Medical Academy, Haydarpasa Training Hospital, Istanbul, Turkey.
J Gastroenterol Hepatol. 2003 Oct;18(10):1162-7. doi: 10.1046/j.1440-1746.2003.03141.x.
Regional changes in cerebral blood flow in patients with chronic hepatitis, cirrhosis and subclinical hepatic encephalopathy were investigated in the present study using single photon emission computed tomography (SPECT).
Twenty patients with cirrhosis, 11 patients with chronic hepatitis, and nine healthy controls were included in the study. Cerebral SPECT were obtained for all patients. The percentages of cerebral blood flow of 14 regions to the cerebellar blood flow were determined. Only the patients with cirrhosis underwent psychometric evaluation: visual evoked potentials (VEP) measurements and electroencephalogram (EEG) recordings along with blood levels of albumin, bilirubin, and ammonia were measured and prothrombin time was determined in cirrhotic patients. These patients were classified according to the Child-Pugh classification.
Among cirrhotic patients, six had abnormal results in VEP studies, 11 in psychometric tests and with six in EEG evaluation. Any abnormality in psychometric tests and/or VEP studies is taken as the main criterion; subclinical hepatic encephalopathy was detected in 12 of 20 patients. According to SPECT results in patients with subclinical encephalopathy, a statistically significant decrease in cerebral blood flow in right thalamus and nearly significant decrease in left thalamus were observed. Regional blood flow was significantly higher in the frontal lobes of patients with cirrhosis when compared with healthy controls. Similarly, cerebral blood flow in frontal and cingulate regions was significantly higher in patients with chronic hepatitis than in healthy controls. There was no relationship between cerebral blood flow and blood levels of ammonia or Child-Pugh score, in cirrhotic patients.
Significant changes in cerebral blood flow may be present in chronic liver diseases and the authors suggest that the measurement of changes in cerebral blood flow might be useful in detecting subclinical hepatic encephalopathy.
本研究采用单光子发射计算机断层扫描（SPECT）对慢性肝炎、肝硬化及亚临床肝性脑病患者脑血流的区域变化进行研究。
本研究纳入了20例肝硬化患者、11例慢性肝炎患者和9名健康对照者。对所有患者进行了脑SPECT检查。测定了14个区域脑血流与小脑血流的百分比。仅对肝硬化患者进行了心理测量评估：测量了视觉诱发电位（VEP）和脑电图（EEG），并测定了肝硬化患者的白蛋白、胆红素和氨的血药浓度以及凝血酶原时间。这些患者根据Child-Pugh分类法进行分类。
在肝硬化患者中，6例VEP研究结果异常，11例心理测量测试结果异常，6例EEG评估结果异常。以心理测量测试和/或VEP研究中的任何异常作为主要标准；20例患者中有12例检测出亚临床肝性脑病。根据亚临床脑病患者的SPECT结果，观察到右侧丘脑脑血流有统计学意义的下降，左侧丘脑脑血流有近乎显著的下降。与健康对照相比，肝硬化患者额叶的区域血流显著更高。同样，慢性肝炎患者额叶和扣带回区域的脑血流显著高于健康对照。在肝硬化患者中，脑血流与血氨水平或Child-Pugh评分之间没有关系。
慢性肝病患者脑血流可能存在显著变化，作者认为脑血流变化的测量可能有助于检测亚临床肝性脑病。
