The fMRI Study of Auditory Pathways Reorganization in Unilateral Sensorineural Hearing Loss

Objective To observe the difference of auditory pathways between normal hearing subjects and unilateral sensorineural hearing loss(USNHL)patients and to study the reorganization of functional auditory pathways in USNHL.Materials and Methods Thirty nirmal hearing subjects,13 right USNHL patients and 10 left USNHL patients underwent MR imaging including T1WI,GRE EPI fMRI and 3D GRE T1WI at stimulation of 500 Hz pure-sound.All images were dealed with AFNI.The activation areas were considered as 5 mm radius and 300 mm3 continuous stimulating areas when.Results The stimulating strength of auditory cortex(AC),medial geniculate body(MGB) and inferior colliculus(IC) in the opposite side were higher than that in the ipsilateral side,that was contralateral dominance in normal hearing subjects.It was contralateral dominance in MGB and IC but ipsilateral dominance in AC in USNHL patients.Conclusion The normal hearing subjects showed contralateral dominance of auditory pathways.But USNHL patients showed auditory pathways reorganization at cortical levels.