State Key Laboratory of Oncology in South China and Department of Medical Imaging and Interventional Radiology, Sun Yat-Sen University Cancer Center, Guangzhou, China.
Liver Int. 2013 Mar;33(3):375-83. doi: 10.1111/liv.12096.
Many studies have reported that cognitive deficits exist in cirrhotic patients without overt hepatic encephalopathy (OHE). However, the neurobiological mechanisms underlying these deficits are still not fully understood.
To investigate regional activity abnormalities in patients with hepatitis B virus-related cirrhosis (HBV-RC) without OHE using resting-state functional MRI (Rs-fMRI), and to examine the relationship between regional activity abnormalities and impaired cognition.
A newly reported regional homogeneity (ReHo) approach was used to compare the local synchronization of Rs-fMRI signals in 32 patients with HBV-RC without OHE and 32 well-matched healthy controls. Cognition was measured in all patients using psychometric hepatic encephalopathy score (PHES) tests, and the relationship between ReHo variation and PHES was analysed.
Relative to healthy controls, the cirrhosis group showed high ReHo in the prefrontal cortex, and widespread low ReHo in visual association areas (left lingual gyrus, middle temporal gyrus and right middle occipital gyrus), motor association areas (bilateral precentral gyrus and paracentral lobule) and the bilateral precuneus. Correlation analysis of the mean ReHo values in different brain areas and PHES in cirrhotic patients revealed a significantly positive correlation in the left lingual gyrus (r = 0.352; P = 0.048), right middle occipital gyrus (r = 0.453; P = 0.009) and bilateral precentral gyrus (left: r = 0.436, P = 0.013; right: r = 0.582, P < 0.001), paracentral lobule (r = 0.485; P = 0.005) and precuneus (r = 0.468; P = 0.007).
Our results provide information on the pathophysiological mechanisms underlying cognitive alterations in cirrhotic patients and demonstrate the feasibility of using Rs-fMRI with ReHo analysis as a noninvasive modality with which to detect the progression of cognitive changes in cirrhotic patients.
许多研究报告称，无显性肝性脑病（OHE）的肝硬化患者存在认知缺陷。然而，这些缺陷的神经生物学机制仍未完全阐明。
使用静息态功能磁共振成像（Rs-fMRI）研究乙型肝炎病毒相关肝硬化（HBV-RC）无 OHE 患者的区域活动异常，并探讨区域活动异常与认知障碍的关系。
采用一种新的局部一致性（ReHo）方法，比较 32 例 HBV-RC 无 OHE 患者和 32 例匹配良好的健康对照者的 Rs-fMRI 信号局部同步性。对所有患者进行心理肝性脑病评分（PHES）测试，以评估认知功能，并分析 ReHo 变化与 PHES 的关系。
与健康对照组相比，肝硬化组前额叶皮质的 ReHo 升高，视觉联合区（左侧舌回、中颞回和右侧中枕回）、运动联合区（双侧中央前回和旁中央小叶）和双侧楔前叶的 ReHo 降低。对肝硬化患者不同脑区平均 ReHo 值与 PHES 值的相关性分析显示，左侧舌回（r = 0.352，P = 0.048）、右侧中枕回（r = 0.453，P = 0.009）和双侧中央前回（左侧：r = 0.436，P = 0.013；右侧：r = 0.582，P < 0.001）、旁中央小叶（r = 0.485，P = 0.005）和楔前叶（r = 0.468，P = 0.007）之间存在显著正相关。
本研究结果为肝硬化患者认知改变的病理生理机制提供了信息，并证明了使用 Rs-fMRI 和 ReHo 分析作为一种非侵入性手段来检测肝硬化患者认知变化进展的可行性。
