Learning Objectives:
Objective: The pathogenesis of idiopathic sudden sensorineural hearing loss (ISSHL) is still unknown, but an inner ear circulatory disturbance has been considered to be one possible pathogenesis. To date, there have been no reports evaluating the possibility of the labyrinthine artery infarction in ISSHL patients by ultra-high-field MRI. The present study aims to compare the detection rates of the labyrinthine artery in subjects with idiopathic sudden sensorineural hearing loss and in normal hearing controls using 7-T MRI.
Study Design: cross sectional study
Setting: Tertiary referral center
Subjects and Methods: In 22 patients (11 males, 11 females) with ISSHL and 43 volunteers (29 males, 14 females) with normal hearing, 7-T MRI (Discovery MR950, GE Medical Systems) was performed with the 3D time-of-flight spoiled gradient echo (3D TOF SPGR) sequence to compare the detection rates of the labyrinthine artery.
Results: MRI scans were performed from 3 to 173 days after onset. Of the 22 patients with ISSHL, 8 showed complete recovery, 10 showed partial recovery and the rest showed no recovery. The labyrinthine artery was depicted in 44 of 44 ears (100%) in the ISSHL group and 85 of 86 (98.8%) ears in the normal hearing group, with no significant difference in detection rates. Two ISSHL patients out of 4 patients with no recovery showed total deafness, but the labyrinthine artery was also depicted in both patients.
Conclusion: The present study is the first to report depiction of the labyrinthine artery by 7-T MRI. These preliminary results indicate occlusion of the labyrinthine artery would be rare in the pathogenesis of ISSHL and they also demonstrate that the labyrinthine artery could be detected by ultra-high-field MRI.
