Structural And Resting-state FMRI Study Of Hepatic Myelopathy

Part1 A voxel-based morphometric study of the gray matter structure in hepatic myelopathyObjective To analyze the differences of gray matter(GM)in patients with HM by using VBM.Methods 23 patients with HM,23 patients with hepatic encephalopathy but without HM and 24 demographically matched HCs were recruited in our study and Siemens 3.0T Trio Tim MR scanner was used to obtain T1 WI three-dimensional brain volume sequences of the three groups.The data were processed with SPM8 in Matlab 2012 platform.Inter-group analysis was performed with two-sample t-test.The brain areas of which the cluster number was larger than 50 and p<0.05(FWE correction)were chosen as the statistically significant areas.Results Compared to HCs,VBM displayed increased GM volume in HM mainly located in bilateral thalamus and left calcarine,and extensively decreased GM volume in bilateral cerebellum,vermis,right posterior cingulate gyrus,bilateral putamen,left hippocampus and right lingual gyrus.Compared to Non-HM,analysis of VBM of HM revealed a decrease in GM volume primarily in left precentral lobe,left postcentral lobe,right angular gyrus and left occipital lobe.Compared to HCs,VBM displayed increased GM volume in Non-HM mainly located in bilateral thalamus,left precentral lobe,left postcentral lobe,right angular gyrus,left inferior and temporal gyrus,and decreased GM volume in bilateral cerebellum,vermis,corpus collosum,bilateral putamen,left fusiform,right lingual gyrus and left parahippocampus.Conclusion The GM volume of multiple brain regions related to motor loops of HM changed,which could play a significant role in revealing the underlying pathophysiological mechanism of HM.Part2 Altered regional homogeneity of spontaneous brain activity in hepatic myelopathyObjective This study intended to investigate the differences of Re Ho in resting state in patients with HM by applying rs-f MRI(resting state functional MRI).Methods 23 patients with HM,23 patients with hepatic encephalopathy but without HM and 24 demographically matched HCs were performed the rs-f MRI.The differences of Re Ho between the two groups were acquired and analyzed by processing softwares.Results Compared with HCs,patients with HM showed increased Re Ho in the bilateral cingulum,bilateral paracentral lobule,bilateral middle frontal gyrus,right precentral gyrus,right insula,right superior frontal gyrus and left inferior frontal gyrus and decreased Re Ho in the left middle temporal gyrus,right fusiform and left parahippocampal gyrus.No significant discrepancy was found between HM and Non-HM.Conclusion Abnormal Re Ho was found in several motor-related regions in HM,which may be one of the etiologies that cause the impairment of motor functions of HM patients.