Department of Gastroenterology, G. B. Pant Hospital, New Delhi, India.
Hepatobiliary Pancreat Dis Int. 2010 Feb;9(1):27-32.
Minimal hepatic encephalopathy (MHE) impairs quality of life and predicts overt hepatic encephalopathy (HE) in cirrhotic patients. Diagnosis of MHE requires cumbersome tests. Lactulose is effective in the treatment of MHE. This study aimed to evaluate the use of critical flicker frequency (CFF) for the diagnosis of MHE in cirrhotic patients after treatment.
One hundred and ten patients were evaluated by psychometry (number connection tests A, B or figure connection tests A, B), P300 auditory event related potential (P300ERP), venous ammonia, and CFF for MHE. MHE was diagnosed by abnormal psychometry (>2SD age matched controls) and P300ERP. MHE patients were treated with lactulose for one month. Response was defined by normalization (<2SD of matched controls) of both psychometry and P300ERP.
Of the 110 patients [Child Turcott Pugh score A:B:C 39:42:29 (age 41.6+/-11.6 years, M:F 82:28)], 75 (68%) had abnormal results of psychometric tests, and 74 (67%) had prolonged P300ERP. Fifteen (20%) patients with abnormal results of psychometric tests had normal P300ERP. Thus sixty (54.5%) patients were diagnosed as having MHE. After treatment for one month, 34 (57%) recovered while 26 (43%) continued to have abnormal resents of psychometric or P300ERP tests. CFF was <39 Hz in 72 (65.4%) patients before treatment and in 20 (33.3%) after treatment. CFF sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for the assessment of recovery of MHE were 65%, 91%, 85%, 77% and 80%, respectively.
CFF is a simple, relatively reliable, and accurate test without any dependence on age or literacy in the diagnosis and assessment of recovery of patients with MHE.
轻微型肝性脑病（MHE）会降低生活质量，并预测肝硬化患者出现显性肝性脑病（HE）。MHE 的诊断需要繁琐的检查。乳果糖对 MHE 的治疗有效。本研究旨在评估临界闪烁频率（CFF）在治疗后诊断肝硬化患者 MHE 的应用。
通过心理测量学（数字连接测试 A、B 或图形连接测试 A、B）、P300 听觉事件相关电位（P300ERP）、静脉血氨和 CFF 对 110 例患者进行 MHE 评估。MHE 通过异常心理测量学（>2SD 年龄匹配对照组）和 P300ERP 进行诊断。MHE 患者接受乳果糖治疗一个月。通过心理测量学和 P300ERP 两者的正常化（<2SD 匹配对照组）来定义治疗反应。
110 例患者中（Child Turcott Pugh 评分 A：B：C 为 39：42：29[年龄 41.6+/-11.6 岁，M：F 为 82：28]），75 例（68%）心理测量学检查结果异常，74 例（67%）P300ERP 延长。15 例（20%）心理测量学检查结果异常的患者 P300ERP 正常。因此，60 例（54.5%）患者被诊断为 MHE。治疗一个月后，34 例（57%）患者恢复，26 例（43%）患者心理测量学或 P300ERP 检查仍异常。治疗前，72 例（65.4%）患者的 CFF<39Hz，治疗后 20 例（33.3%）患者的 CFF<39Hz。CFF 对评估 MHE 恢复的敏感性、特异性、阳性预测值、阴性预测值和诊断准确性分别为 65%、91%、85%、77%和 80%。
CFF 是一种简单、相对可靠且准确的测试，在诊断和评估 MHE 患者的恢复方面，无任何年龄或文化程度的依赖性。
