ABSTRACT
Objective@#To explore the difference of radiological imaging features of delayed encephalopathy after carbon monoxide poisoning (DECMP) and acute carbon monoxide poisoning (ACMP) , and the correlation between the imaging findings and clinical prognosis of the disease.@*Methods@#The correlation between imaging findings and clinical manifestations and prognosis of 95 patients with moderate and severe acute carbon monoxide poisoning were retrospectively analyzed. In the above 95 cases, there were 62 cases of ACMP and 33 cases of DEACMP. All patients underwent conventional CT, MRI and magnetic resonance diffusion tensor imaging (DTI) . Circular regions of interest (ROI) measurement was used for analysis of average diffusion coefficient (ADC) value and fractional anisotropy (FA) value of the MRI and DTI imaging manifestations in different brain regions.@*Results@#The main clinical manifestation of moderate acute carbon monoxide poisoning was consciousness disorder and fatigue; Severe poisoning patients showed deep coma as the main clinical manifestations; The most prominent clinical manifestations of DEACMP were mental disorders and neurological impairment in the extrapyramidal system. A total of 95 cases with moderate or severe CO poisoning showed unilateral or bilateral cerebral cortex, bilateral basal ganglia (white ball) , cerebral white matter around bilateral ventricles or bilateral centrum semiovale, around bilateral ventricles cerebral white matter around bilateral ventricles and bilateral centrum semiovale, cerebral cortex and subcortical involvement. CT showed normal or low density shadow.MRI showed that the lesion T1WI presented slightly low or equal signal, T2WI and FLAIR sequences showed equal, a slightly higher or high signal; DWI sequence showed slightly higher or high signal. ADC value and FA value in different brain white matter regions of DEACMP group was significantly lower than those of ACMP group (P<0.05) , especially for those around semi oval center and lateral ventricles of the brain white matter (P<0.01) ; The ADC values increased significantly, FA value decreased significantly in the nerve nucleus (P<0.05) , especially for ADC values in globus pallidus (P<0.01) .@*Conclusion@#DTI can evaluate the brain tissue damage in patients with DEACMP more early and more accurately.
ABSTRACT
Objective We investigated the changes of the motorial network in patients suffered from brain tumors adjacent to the central sulcus occurred with reorganization of motor function using function connectivity MRI(fcMRI)technique in order to provide the new evidence for the compensational hypothesis of the reorganization caused by focal lesions.Methods Using 1.5 T MRI unit,14 patients with brain tumors in the vicinity of the central sulcus occurred with reorganization of motor function and 6 normal volunteers were examined with fcMRI technique while the subjects performed no task.By selecting seed voxels(region of interest)in the regions showing the most activation in M1 area on the activated map and cross correlating with every voxel within the brain,the fcMRI maps based on unilateral primary motor(M1)area were calculated.The location,extent and volume of the region showing significant connectivity to the several seed voxel,such as left/right M1 area in the health group and affected/unaffected M1 area in the patient group were evaluated on the fcMRI map.Results In healthy group,the extent and volume of the region showing significant connectivity to the left M1 area[(9514.17±186.92)mm3]were almost similar to those to the right M1 area [(9364.67±382.75)mm3].There showed no significant difference in motor connectivity between the two groups(P>0.05).In the tumor group,the volume of regions showing significant connectivity to the M1 area located in the affected hemisphere [(11193.14±811.29)mm3]was obviously higher than that of regions based on the seed voxel in the unaffected side[(6549.86±400.94)mm3](t=20.383,P＜0.01).The volume was significantly different among the regions showing high connectivity to the M1 of the affected side in patient group.those showing significant connectivity to the left M1 and fight M1 in health group(P＜0.01),the former was the biggest(P＜0.01).The extent of the regions showing connectivity to the affected M1 was consistent with the reorganization area of motor function revealed by fMRI.The volume of regions showing significant connectivity to M1 area of unaffected hemisphere in patient group showed significant difference compared with those showing significant connectivity to the left M1 and right M1 in health group(P＜0.01),the former was smallest(LSD,P＜0.01).especially in the affected hemisphere.It might mean the disrupted functional connectivity between the M1 area of unaffected hemisphere in patient group and motor area located in the collateral side.Conclusion The increased connectivity between the M1 area of the affected hemisphere and the other motor cortex might indicate that the reorganization in the motor pathway and the formation of the potential compensatory network second to the impairment of the normal motor pathway resulted in the functional reorganization of the motor cortex.The fcMRI technique might be a valuable approach to reveal the pathophysiological changes of nerve network caused by brain tumor.