Prognostic Value of Labyrinthine 3D-FLAIR Abnormalities in Idiopathic Sudden Sensorineural Hearing Loss

Abstract

Background and purpose: According to recent research, modern MR imaging can detect the presense of abnormalities on labyrinthine. Our aim was to report the patterns and prognostic role of abnormal findings on labyrinthine imaging in patients with sudden sensorineural hearing loss.

Materials and methods: This study comprised 113 patients who were diagnosed with unilateral sudden sensorineural hearing loss and underwent 3T MR imaging, including pre-/postcontrast 3D fluid-attenuated inversion recovery and T1-weighted imaging. We analyzed abnormalities on MR imaging and correlated them with audiometric results.

Results: Thirty-one (27%) patients showed abnormal findings on labyrinthine MR imaging in the affected ear. The initial/final hearing levels of the MRI+ group (91 ± 25/73 ± 27 dB hearing loss) were significantly worse than those of the MRI- group (69 ± 30/48 ± 24 dB hearing loss). The incidence of abnormalities on labyrinthine MR imaging was significantly lower (3 of 40, 8%) in 40 patients with initial mild-to-moderate hearing loss than in those with profound hearing loss (16 of 34, 47%). Considering hearing improvement by the Siegel criteria, the rate of complete or partial recovery was significantly higher in the MRI- group (34%) than in the MRI+ group (10%). In patients with initial severe or profound hearing loss, the MRI- group showed greater hearing improvement (38 ± 21 dB) than the MRI+ group (23 ± 22 dB).

Conclusions: Abnormalities on labyrinthine MR imaging were found in 27% of patients with sudden sensorineural hearing loss. The initial hearing loss was worse in the MRI+ group than in the MRI- group. In patients with initial severe and profound hearing loss, the presence of abnormalities on labyrinthine MR imaging indicated a poor prognosis.

Fig 1.

Study population excluded and enrolled in this study.

Fig 2.

Precontrast axial scans of 3D-FLAIR MR imaging in right inner ear of a 63-year-old man with right sudden sensorineural hearing loss with vertigo. Bright signals (arrows) are visible only in the right cochlea and vestibule at the level of the basal turn (A) and midturn (B) of the cochlea and vestibule, not in the left healthy cochlea and vestibule (open arrows).

Fig 3.

Hearing improvement according to the Siegel criteria in the MRI+ and MRI− groups. CR indicates complete recovery; PR, partial recovery; SI, slight improvement; NR, no recovery.

Fig 4.

Initial pretreatment and final posttreatment audiologic findings and the improvement of hearing (ΔPTA) in the MRI− and MRI+ groups according to the initial hearing loss. ΔPTA indicates the difference of mean pre- and posttreatment.