Purpose. Gray matter volume loss, regional cortical thinning, and local gyrification index alteration have been documented in minimal hepatic encephalopathy (MHE). Fractal dimension (FD), another morphological parameter, has been widely used to describe structural complexity alterations in neurological or psychiatric disease. Here, we conducted the first study to investigate FD alterations in MHE. Methods and Materials. We performed high-resolution structural magnetic resonance imaging on cirrhotic patients with MHE () and healthy controls (). We evaluated their cognitive performance using the psychometric hepatic encephalopathy score (PHES). The regional FD value was calculated by Computational Anatomy Toolbox (CAT12) and compared between groups. We further estimated the association between patients’ cognitive performance and FD values. Results. MHE patients presented significantly decreased FD values in the left precuneus, left supramarginal gyrus, right caudal anterior cingulate cortex, right isthmus cingulate cortex, right insula, bilateral pericalcarine cortex, and bilateral paracentral cortex compared to normal controls. In addition, the FD values in the right isthmus cingulate cortex and right insula were shown to be positively correlated with patients’ cognitive performance. Conclusion. Aberrant cortical complexity is an additional characteristic of MHE, and FD analysis may provide novel insight into the neurobiological basis of cognitive dysfunction in MHE.

中文翻译：

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肝硬化最小型肝性脑病患者皮质复杂性降低。

目的。在最小型肝性脑病（MHE）中已记录了灰质体积减少，局部皮质变薄和局部回旋指数改变。分形维数（FD）是另一个形态学参数，已广泛用于描述神经或精神疾病的结构复杂性变化。在这里，我们进行了第一项研究，以调查MHE中的FD改变。方法和材料。我们对肝硬化合并MHE的患者进行了高分辨率的结构磁共振成像（）和健康对照（）。我们使用心理肝性脑病评分（PHES）评估了他们的认知表现。通过计算解剖工具箱（CAT12）计算区域FD值并在组之间进行比较。我们进一步估计了患者的认知能力和FD值之间的关联。结果。与正常对照相比，MHE患者的左前神经突，左上臀回，右尾前扣带回皮层，右峡带扣回皮层，右岛，双侧黄car皮和双侧中央旁皮层的FD值显着降低。此外，右峡部扣带回皮层和右岛中的FD值与患者的认知能力呈正相关。结论。异常的皮质复杂性是MHE的另一个特征，FD分析可能为MHE认知功能障碍的神经生物学基础提供新颖的见解。