DTI Combined With FMRI To Explore The Recovery Mechanism Of Melodic Intonation Therapy In The Treatment Of Broca Aphasia

Objective: To explore the mechanism of brain function remodeling after melody intonation therapy(MIT)in the treatment of Broca aphasia through Diffusion tensor imaging(DTI)and resting-state functional magnetic resonance imaging(rs-f MRI).DTI was used to provide the microscopic information of fibrous tissue structure related to language function and rs-f MRI can provide the activation of brain functional areas at baseline.Methods: A total of 37 patients with Broca aphasia after stroke in our hospital from January 2019 to June2020 were randomly divided into two groups: control group(n=19)were treated with routine speech therapy,experimental group(n=18)were treated with MIT and routine speech therapy.The therapeutic effects of the two groups were observed with a complete set of western aphasia tests after 2 months of treatment.Patients in both groups were scanned by DTI and rs-f MRI before and after treatment.1.DTI images: intra-group comparison: the fractional anisotropy(FA)of bilateral Broca area and arcuate fasciculus were measured and compared before and after treatment in the two groups separately.Comparison between groups: FA values of bilateral Broca area and arcuate fasciculus were compared between the two groups before and after treatment.2.rs-f MRI images: Amplitude of low frequency fluctuation(ALFF)analysis was used to compare the difference of brain activation between the two groups before and after treatment.Results: 1.The DTI results show that: In the control group,there were significant differences in FA values of left Broca area and left arcuate fasciculus before and after treatment(P<0.001),but there was no significant difference between right Broca area(P=0.097)and right arcuate fasciculus(P=0.088).Comparison of experimental group before and after therapy showed: FA of both Broca and arcuate fasciculus were statistically significant(Bilateral arcuate fasciculus and left Broca area P<0.001,right Broca area P=0.008).There was no significant difference in FA of bilateral Broca area and arcuate fasciculus between the experimental group and the control group before therapy(P>0.05).2 months after therapy,between the experimental group and the control group,FA of right arcuate fasciculus were statistically significant(P=0.008).There was no significant difference in FA between left arcuate fasciculus and bilateral Broca(P>0.05).2.The results of rs-f MRI showed that: No statistically significant brain regions were found in the bilateral hemispheres of the two groups before treatment.After treatment,the ALFF values of right superior frontal gyrus,right middle frontal gyrus,right inferior frontal gyrus,right anterior cingulate gyrus,bilateral straight gyrus and medial frontal gyrus in the experimental group were significantly higher than those in the control group(P<0.01).Conclusions:After the intensive rehabilitation treatment of Broca aphasia patients with melodic intonation therapy,DTI showed that the FA value of the right arcuate fasciculus bundle increased,and rs-f MRI showed that the right frontal lobe was mainly activated after MIT treatment,suggesting that the therapeutic mechanism of MIT may be related to the right cerebral hemisphere.