Res Vestib Sci.  2019 Dec;18(4):103-110. 10.21790/rvs.2019.18.4.103.

The Value of Posterior Semicircular Canal Function in Predicting Hearing Recovery of Sudden Sensorineural Hearing Loss

• Shin JW
• Kim SW
• Kim YW
• Jang W
• Kim BH
• Lim YS
• Park SW
• Cho CG
• Park JH

• KMID: 2470690
• DOI: http://doi.org/10.21790/rvs.2019.18.4.103

Abstract

OBJECTIVES
Postulated etiologies for idiopathic sudden sensorineural hearing loss (SSNHL) include viral cochleitis, microvascular events. If SSNHL is caused by vascular compromise of common cochlear artery that supplies cochlea and posterior semicircular canal (PC), PC also can be damaged with cochlea. We aim to evaluate the prognostic value of PC function in relation to hearing recovery of SSNHL.
METHODS
Seventy-six patients who were diagnosed and treated for SSNHL and who underwent video head impulse test (vHIT) and follow-ups for more than 3 months were reviewed retrospectively. We defined impairment of PC function as lower PC gain (<0.7) or definite overt/covert saccade in vHIT. Patients were divided into 3 groups: group 1, SSNHL without dizziness; group 2, SSNHL with dizziness and impaired PC function; group 3, SSNHL with dizziness, but intact PC function. Hearing thresholds were repeatedly measured on the initial visit, 1 week, 1 month, and 3 months after treatment. Treatment outcome was analyzed by comparing hearing recovery rate using Siegel's criteria and posttreatment audiometric changes among 3 groups.
RESULTS
Thirty-two (29.6%), 33 (30.6%), and 43 patients (39.8%) were included into the groups 1, 2, and 3, respectively. The hearing recovery rate of the group 2 (39.4%) was significantly lower than that of groups 1 (65.6%) and 3 (65.1%) (p=0.043). Pre- and posttreatment changes of the PTA threshold was significantly lower in group 2 than group 1 (p=0.009). The change of speech discrimination in each group were not different.
CONCLUSIONS
Our findings suggest that the presence of PC impairment may be a poor prognostic sign for hearing recovery in patients with SSNHL.

Keyword

Sudden sensorineural hearing loss; Posterior semicircular canal; Head impulse test

MeSH Terms

Arteries
Cochlea
Dizziness
Equipment and Supplies
Follow-Up Studies
Head Impulse Test
Hearing Loss, Sensorineural*
Hearing*
Humans
Retrospective Studies
Saccades
Semicircular Canals*
Speech Perception
Treatment Outcome