Prognostic value of initial electronystagmography findings in idiopathic sudden sensorineural hearing loss without vertigo.

OBJECTIVE

We used electronystagmography (ENG) to characterize recurrent hearing loss and its progression to definite Ménière's disease in patients with idiopathic sudden sensorineural hearing loss (SSHL) without subjective vertigo.

METHODS

We reviewed medical records of 1,334 patients with unilateral hearing loss initially diagnosed with idiopathic SSHL between 1985 and 2003 at our university hospital. Of the 1,334 patients, we examined 127 (86 with low-tone and 41 with high-tone SSHL) who underwent ENG within 30 days of the initial diagnosis and who could be followed up during the long term.

RESULTS

Spontaneous nystagmus (SN) was observed in approximately half of the vertigo-unaccompanied group. Long-term follow-up with a mean of 67 months revealed that the recurrence rate of hearing loss was 51.2% in low-tone SSHL patients with SN. The recurrence rate of hearing loss was 27.9% in low-tone SSHL patients without SN. Progression to Ménière's disease occurred in 14.0% of the low-tone-type and 12.5% of the high-tone-type patients when SN was detected. In contrast, in both the low-tone-type and high-tone-type groups, none developed Ménière's disease when SN was absent.

CONCLUSION

Our results suggest that the initial ENG findings could provide prognostic information for idiopathic SSHL patients, even those who have no vestibular symptoms at the first visit.