Registering grades of sudden deafness to predict the hearing outcome via an inner-ear test battery

Abstract

Objectives: An inner ear test battery comprising audiometry and ocular vestibular-evoked myogenic potential (oVEMP), cervical VEMP (cVEMP), and caloric tests was applied to patients with sudden deafness to map their lesions and predict hearing outcome. Design: Retrospective study. Study sample: Seventy-five patients with unilateral sudden deafness underwent an inner-ear test battery. Registering the grades of sudden deafness was based on the number of abnormal test results in the inner ear test battery. Results: After treatment for three consecutive months, mean hearing gain declined significantly from Grade I (one abnormal test) to Grade IV (four abnormal tests). Significant relations existed between hearing outcome and oVEMP test results (p < 0.05), caloric test results (p < 0.05), but not cVEMP test results and pre-treatment mean hearing level. Combined caloric and oVEMP test results demonstrated a stronger predictor with a c statistic of 0.722 than either test alone, indicating that this regression model fits the whole set of observations well and is effective in predicting the hearing outcome. Conclusion: Abnormal caloric and oVEMP test results in sudden deafness patients may indicate poor prognosis for hearing improvement, whereas hearing recovery can be anticipated when both tests reveal normal responses.

Key Words::

• Sudden deafness
• ocular vestibular-evoked myogenic potential (oVEMP)
• cervical vestibular-evoked myogenic potential (cVEMP)
• inner ear test battery

Declaration of interest: No conflict of interest declared.

This work was supported by the National Science Council, Taipei, Taiwan (grant no. NSC 99-2314-B002-041-MY3).