The Study Of Cerebral Cortex Functional Recombination In Preschool Children With Congenital Sensorineural Hearing Loss: A Resting-state FMRI

Objective:The purpose of the part is to explore the characteristics of brain function of preschool children with sensorineural hearing loss(SNHL)by studying the change of amplitude of low-frequency fluctuation(ALFF),regional homogeneity(Re Ho)and functional connectivity(FC)under resting-state,and to further reveal the characteristics of cortical functional reorganization in pre-school children with congenital SNHL.Methods:We had collected resting state f MRI(Rs-f MRI)datas from 63 patients diagnosed with preschool congenital SNHL and 32 pre-school healthy controls(HC)from May2017 to June 2020,and followed up the categories of auditory performance(CAP)and speech intelligibility rating(SIR)scores 6 months after cochlear implantation(CI).Firstly,DPABI and SPM12 analysis software were used to preprocess Rs-f MRI datas,including time processing(removing the first 10 time points and time layer correction)and spatial processing(head movement correction,spatial standardization,spatial smoothing,linear drift removal and filtering).Then the whole brain function parameters mean ALFF(m ALFF)and Re Ho were calculated.And we used seed-point-based FC analysis to define bilateral primary auditory cortex(PAC)as seed points,time series method was used to calculate the FC intensity maps of the left and right PAC and other brain regions.Finally,the maps of m ALFF Re Ho and FC were tested by two-sample T-test with gender,age and head movement parameters as covariates,and the results corrected based on cluster level FWE or FDR were statistically different(P<0.05).Spearman correlation analysis was performed between m ALFF value and CAP score in the brain regions with changes in m ALFF,and the results with P < 0.05 were statistically significant.Results:Compared with the control group:(1)m ALFF analysis showed that the m ALFF of bilateral superior frontal gyrus(BA9),bilateral middle frontal gyrus(BA10),left inferior frontal gyrus(BA47),bilateral orbitofrontal gyrus(BA11)and bilateral superior temporal gyrus(BA38)were increased in SNHLgroup;However the m ALFF of bilateral thalamus,Calcarine fissure cortex(BA18)and right posterior cingulate cortex(BA23)were decreased(P < 0.05,FDR corrected).(2)Re Ho analysis showed that compared with HC group,the Re Ho were decreased in bilateral superior temporal gyrus(BA38,41),bilateral orbitofrontal gyrus(BA11),left middle frontal gyrus(BA10),left inferior frontal gyrus(BA47)and left insular lobe(BA13);while the levels of Re Ho in bilateral thalamus,right caudate nucleus and right anterior central gyrus(BA3)were increased.(2)FC analysis based on seed points showed that the FC between bilateral superior temporal gyrus(BA41),left superior frontal gyrus(BA6),left paracentral lobule(BA4),right posterior central gyrus(BA4),right occipital lobe(BA19),bilateral thalamus,and bilateral insulas(BA48)were enhanced in SNHL group when the right PAC was used as seed point.When the left PAC was used as Seed,the FC between bilateral anterior central gyrus(BA6),posterior central gyrus(BA4),left inferior parietal lobule(BA40),left occipital lobe(BA19),right occipital lobe(BA18),dorsal anterior cingulate cortex(BA24),bilateral thalamus,bilateral insulas(BA48),and right superior temporal gyrus(BA41)were enhanced in SNHL group(P < 0.05,FDR corrected).Correlation analysis showed that m ALFF values of left and right middle frontal gyrus(r =-0.2826,P = 0.0248;r =-0.2521,P = 0.0463),right superior frontal gyrus(r =-0.2728,P = 0.0305),left inferior frontal gyrus(r =-0.2507,P = 0.0475),right orbital frontal gyrus(r =-0.2554,P = 0.0434)and left orbital frontal gyrus(r =-0.2573,P = 0.0418)were negatively correlated with CAP scores.The FC values of the left superior temporal gyrus(r =-0.2566,P = 0.0423),the right superior temporal gyrus(r =-0.2679,P = 0.0338)and the left occipital lobe(r =-0.2729,P = 0.0304)were negatively correlated with the CAP score when the right PAC was used as Seed.When the Seed of the left PAC was taken as the Seed,the FC values between the right superior temporal gyrus(r =-0.3124,P = 0.0127),the left occipital lobe(r =-0.2975,P = 0.0179),the right occipital lobe(r =-0.2491,P =0.0490),the left posterior central gyrus(r =-0.3269,P = 0.0089)and the right thalamus(r =-0.2638,P = 0.0367)were negatively correlated with the CAP score.However,there was no correlation between Re Ho value of different brain regions and clinical CAP score.Conclusion:(1)After hearing deprivation in preschool children with congenital SNHL,the local changes of m ALFF and Re Ho in auditory cortex,visual cortex,somatomotor cortex and prefrontal cortex suggest that the local functions of these cortices have been changed in deaf children,and the prefrontal cortex may play a mediating role in this process.(2)Seed-based FC further analysis showed that the FC between PAC and visual cortex,proprioceptive and motor cortex were enhanced in deaf children after hearing deprivation,suggesting that the auditory and visual cortex,proprioceptive and motor cortex were underwent cortical function recombination or compensation.(3)Correlation analysis results suggested that the functional recombination or compensation of auditory,visual and sensorimotor cortices after hearing deprivation in deaf children may be detrimental to the recovery of hearing and language after CI surgery.