Structural And Resting-state Functional MRI Studies In Suicidal Patients With Depressive Disorder

Chapter Ⅰ Voxel-based morphometry MRI study of gray matter volume changes in depressive disorder with suicidal behaviorObjective: The gray matter volume changes in depressive disorder with suicidal behavior were analyzed by structural magnetic resonance analysis based on voxel-based morphometry(VBM),and to explore the relationship between the gray matter volume changes and clinical characteristics.Method: Twenty-eight depressive patients with suicide(DES),thirtyfive depressive patients without suicide behavior(DEN)and fifty healthy control(HC)subjects who were matched in age,gender and education level were recruited.All MR images were acquired on a 3.0T Siemens MR scanner.High-resolution 3D-T1 and conventional MRI were acquired.The subjects were assessed with Hamilton Depression Scale-17(HAMD),Beck Scale for Suicide Ideation-Chinese Version(BSI-CV),Hamilton Anxiety Scale(HAMA),Social Support Rating Scale(SSRS),Mini-Mental State Examination(MMSE).The data were preprocessed by VBM8-DARTEL.The one-way ANOVA was used to analyze the difference of the gray matter volume among three groups.Post-hoc t test was used to analyze the difference of the gray matter volume between every two groups.Using the Pearson correlation analysis to find out whether the gray matter volume between DES-DEN and DES-HC were related to the clinical scores.Results: 1.There were no significant differences in age,gender,education level among three groups(P > 0.05).There was significant difference in total score of HAMD-l7 and SSRS between the DES group and DEN group(P<0.05).There was no significant difference in total score of HAMA between the DES group and DEN group(P>0.05).2.VBM analysis: Compared with the DEN group,the gray matter volume of the right middle temporal/ right superior temporal gyrus were decreased in the DES group(P <0.001).Compared with the HC group,the gray matter volume of the right orbital frontal gyrus/ right straight gyrus,right inferior temporal gyrus,right middle cingulate gyrus,right hippocampus,left straight gyrus/ left orbital frontal gyrus were decreased in the DES group(P <0.001).Pearson correlation analysis showed no significant relationship between the gray matter volume and the clinical score(P> 0.05).Conclusion: The frontal-temporal-limbic network is associated with depressive disorder with suicidal behavior,and gray volume changes in those brain regions may be a neuropathological basis for the suicidal behavior in depressive disorder.Chapter Ⅱ Resting-state Brain Activity in Suicidal Patients with Depressive DisorderObjective: The brain spontaneous activity in depressive disorder with suicidal behavior were analyzed by resting-state functional magnetic resonance imaging(rs-f MRI),and to explore the relationship between the abnormal brain spontaneous activity and clinical characteristics.Method: Twenty-eight DES,thirty-five DEN and fifty HC subjects who were matched in age,gender and education level were recruited.All MR images were acquired on a 3.0T Siemens MR scanner.rs-f MRI and conventional MRI were acquired.The subjects were assessed with Hamilton Depression Scale-17(HAMD),Beck Scale for Suicide Ideation-Chinese Version(BSI-CV),Hamilton Anxiety Scale(HAMA),Social Support Rating Scale(SSRS),Mini-Mental State Examination(MMSE).regional homogeneity(Re Ho)and amplitude of low frequency fluctuation(ALFF)approach were applied to analyze the rs-f MRI data.The one-way ANOVA was used to analyze the difference of Re Ho and ALFF among three groups.Post-hoc t test was used to analyze the difference of Re Ho and ALFF between every two groups.Using the Pearson correlation analysis to find out whether the Re Ho and ALFF between DES-DEN and DES-HC were related to the clinical scores.Results: 1.There was no significant difference in age,gender,education level among three groups(P > 0.05).There was significant difference in total score of HAMD-l7 and SSRS between the DES group and DEN group(P<0.05).There was no significant difference in total score of HAMA between the DES group and DEN group(P>0.05).2.Re Ho analysis: Compared with the DEN group,the Re Ho values of the right caudate,right triangular part of inferior frontal gyrus,left superior frontal gyrus/ left middle frontal gyrus,right pole of superior temporal gyrus,left pole of middle temporal gyrus/ left pole of superior temporal gyrus,right parahippocampal gyrus were higher than those in DES group(P <0.001).Compared with the DEN group,the Re Ho values of the cuneus/ left calcarine gyrus/ right lingual gyrus/ right cuneus,left inferior parietal gyrus/ left postcentral gyrus,right lingual gyrus were lower than those in DES group(P <0.001).Compared with the HC group,the Re Ho values in the right postcentral gyrus/ right superior parietal gyrus were higher than those in DES group(P <0.001).Compared with the HC group,the Re Ho values in the left triangular part of inferior frontal gyrus were lower than those in DES group(P <0.001).Pearson correlation analysis showed that the mean Re Ho value of the left inferior parietal gyrus/ left postcentral gyrus were negatively correlated with BSI-CV scores(P= 0.010).3.ALFF analysis: Compared with the DEN group,the ALFF values of the right triangular part of inferior frontal gyrus/ right opercular part of inferior frontal gyrus,right pole of middle temporal gyrus,right anterior cingulate gyrus,right caudate were higher than those in DES group(P <0.001).Compared with the DEN group,the ALFF values of the left postcentral gyrus/ left inferior parietal gyrus,right lingual gyrus/ right fusiform gyrus,right postcentral gyrus,right cuneus/ right calcarine gyrus,right superior occipital gyrus were lower than those in DES group(P <0.001).Compared with the HC group,the ALFF values of the right lingual gyrus were higher than those in DES group(P <0.001).Compared with the HC group,the ALFF values of the left straight gyrus were lower than those in DES group(P <0.001).Pearson correlation analysis showed that the mean ALFF value of the right caudate in DES group was positively correlated with the BSI-CV score(P= 0.002),and the mean ALFF value of the left postcentral gyrus/ left inferior parietal gyrus was negatively correlated with BSI-CV score(P= 0.007).Conclusion: 1.In this study,rs-f MRI data of DES,DEN and HC group were analyzed by Re Ho and ALFF methods.We found the DES patients have basically the same pattern of brain functional changes by two different methods.The increased functional area is mainly located in frontal cortex,temporal cortex,the limbic system and the right caudate.The decreased functional area includes parietal cortex and occipital cortex.It’s suggested that suicidal behavior in depressive disorder may involve multiple neurological changes.2.The brain spontaneous activity and amplitude of low-frequency fluctuation in the right caudate and left postcentral/ inferior parietal gyrus were related to suicidal risk.The right caudate and left postcentral/ inferior parietal gyrus temporal may be the potential biomarker for evaluation of suicidal risk in depressive disorder.3.Combined with the first chapter of the results show that brain structure changes lag behind the functional changes in depressive patients with suicidal behavior.