The Correlation Between MRI Rest State And Perfusion Imaging And Cognitive Impairment After Radiotherapy For Nasopharyngeal Carcinoma

Part 1 Correlation between resting state functional magnetic resonance imaging and cognitive impairment after radiotherapy for nasopharyngeal carcinomaObjective: To investigate the dynamic changes of local nerve activity and its correlation with neurocognitive dysfunction in nasopharyngeal carcinoma(NPC)after radiotherapy.Methods: In this study,106 patients were divided into three groups.The first group had 40 patients before radiotherapy(pre-RT),the second group had 29 patients 1-6 months after radiotherapy(post-RT-ED),and the third group had 37 patients > 6 months after radiotherapy(post-RT-LD).Moca,SAS and SDS were used to evaluate the neurocognitive function of NPC patients within 1 hour after RS f MRI examination.Single factor analysis of variance(ANOVA)was used to compare the low frequency amplitude(ALFF)and local consistency(Re Ho)values among the three groups before and after radiotherapy.Spearman correlation analysis was performed between the ALFF and Re Ho values in different brain regions and Moca,SAS and SDS scales.Results: Compared with the group before radiotherapy,the ALFF values of the left dorsolateral superior frontal gyrus,the right cortex around the taloid fissure and the left middle occipital gyrus in the late delayedreaction period after radiotherapy were higher.The Re Ho value of right inferior temporal gyrus and bilateral suboccipital gyrus increased,and the Re Ho value of right inferior frontal gyrus decreased.Compared with the early delayed reaction period after radiotherapy,the ALFF value of the left middle occipital gyrus was higher,and the ALFF value of the left medial superior frontal gyrus,the left orbital middle frontal gyrus,the right anterior cingulate gyrus and the paracingulate gyrus was lower in the late delayed reaction period after radiotherapy.The Re Ho values of right inferior temporal gyrus and left suboccipital gyrus increased,while the Re Ho values of right superior cerebellar margin decreased.After radiotherapy,Mo CA and SAS were significantly different from those before radiotherapy,and some abnormal activated brain areas were correlated with the scale.There was no significant difference in SDS before and after radiotherapy,and there was no correlation between SDS and abnormal activated brain areas.Conclusion: Resting state f MRI can detect the changes of local neuronal activity in patients with nasopharyngeal carcinoma before and after radiotherapy,and there are abnormal activation in different brain regions at different time after radiotherapy,such as ALFF and Re Ho values increasing or decreasing,and some abnormal activated brain regions have certain correlation with cognitive impairment after radiotherapy.Part 2 Relationship between voxel based global cerebral perfusion and cognitive impairment after radiotherapy for nasopharyngeal carcinomaObjective: To investigate the characteristics of voxel based global cerebral perfusion in patients with nasopharyngeal carcinoma(NPC)after radiotherapy and its correlation with neurocognitive impairment scale.Methods: A total of 95 patients in this study were divided into three groups.The first group had 35 patients before radiotherapy(pre-RT),the second group had 28 patients 1-6 months after radiotherapy(post-RT-ED),and the third group had 32 patients more than 6 months after radiotherapy(post-RT-LD).Within 1 hour after 3D PASL examination,MOCA scale,SAS scale and SDS scale were used to evaluate the neurocognitive function of NPC patients.Univariate analysis of variance(ANOVA)was used to compare the CBF values among the three groups before and after radiotherapy.The correlation between CBF and Moca,SAS and SDS was analyzed by Spearman.Results: There was no significant difference in voxel based global cerebral perfusion among the three groups before and after radiotherapy.After radiotherapy,Mo CA,SAS had significant difference compared with those before radiotherapy,while SDS had no significant difference before and after radiotherapy.Conclusion:There was no significant difference in whole brain perfusion based on voxel level before and after radiotherapy for nasopharyngeal carcinoma,and there was no definite correlation between voxel level and cognitive function after radiotherapy.