Characteristic of Sudden Sensorineural Hearing Loss with Objective Vestibular Involvement

Choi, Ki Yong; Kim, Min Tae; Choi, Ji Eun; Jung, Jae Yun; Lee, Min Young

Abstract

BACKGROUND AND OBJECTIVES
To analyze the difference in audiologic-vestibular and clinical characteristics between acute cochlea-vestibulopathy (ACV) and idiopathic sudden sensorineural hearing loss (ISSNHL).
SUBJECTS AND METHOD
We retrospectively analyzed the clinical characteristics of 91 patients diagnosed as sudden hearing loss (ACV; n=20, ISSNHL; n=71). Patients with vestibular hypofunction were categorized as ACV and all others as ISSNHL. Demographics and clinical findings were compared. Audiologic features such as degree of hearing loss, type of audiometric configuration and hearing improvements were analyzed. In addition, vestibular function test results and hearing recovery were further analyzed among ACV group.
RESULTS
Demographics and other clinical findings were not much different between groups. There was a significant difference with respect to audiologic features between the ACV group and ISSNHL group: the initial hearing threshold of the ACV group was higher than that of the ISSNHL group, and their treatment onset was also shorter. There was also a significant difference in the hearing outcome showing very low rate of complete recovery in ACV group. The final hearing threshold of the ACV group was higher than that of the ISSNHL group. Dizziness was the only significant variable in the multiple regression analysis. In the ACV group, the cervical vestibular evoked myogenic potential inter-aural amplitude difference (cVEMP IAD) ratio showed a correlation to the hearing recovery in some frequencies; patients with no cVEMP response showed poor outcome compared to those with cVEMP waveform.
CONCLUSION
The ACV group shows a poor prognosis just as in the case of sudden hearing loss defined in the traditional sense of vertigo. The IAD value of the vestibular evoked myogenic potentials test will be helpful in assessing hearing improvement, especially when a high IAD value at the middle frequency is associated with a poor prognosis.