Objective To observe the vestibular dysfunction in sudden sensorineural hearing loss (SSHL) patients without vertigo. Methods Forty-two cases of unilateral SSHL without vertigo were enrolled in the study from May 2012 to May 2014. All patients underwent air conducted sound elicited oVEMP and cVEMP respectively. Some of them also received caloric test. Sixty-two SSHL patients with vertigo and twenty-five age-and gender-matched normal subjects were recruited as controls to analyze the vestibular dysfunction in SSHL patients without vertigo. Results Abnormal oVEMP was observed in 54.8% affected ears without vertigo (23/42), 64.5% ears with vertigo (40/62), and 26.0% normal ears (13/50). Abnormal cVEMP was observed in 52.4% affected ears without vertigo (22/42), 48.4% ears with vertigo (30/62), and 14.0% normal ears (7/50). Caloric test was operated in 21 SSHL patients without vertigo and 29 patients with vertigo. Abnormal caloric test was observed in 52.4% (11/21) SSHL patients without vertigo and 75.9% (22/29) SSHL patients with vertigo respectively. Statistical significance was found in oVEMP and cVEMP rates between SSHL without vertigo and normal group (PP>0.05)． Conclusion Vestibular function could be damaged in SSHL patients without vertigo．The abnormal rates of oVEMP, cVEMP and caloric test in SSHL patients without vertigo were similar to that of SSHL patients with vertigo.The appearance of vertigo might be irrelevant to the range and extent of vestibular dysfunction.
