A hearing test is carried out in almost all patients complaining of vertigo or dizziness. However, a vestibular function test is rarely performed for patients with sudden deafness. Normal vestibular function cannot necessarily be assumed in cases where patients with sudden deafness have not complained of vestibular-related symptoms. We investigated 71 patients with sudden deafness in whom vestibular function tests with electronystagmography (ENG) were performed in our hospital. They visited our hospital within one month after the onset of hearing loss. 32 patients (45%) had sudden deafness with vestibular-related symptoms, 39 patients (55%) had no vestibular symptom. At the time of an initial consultation, we performed the positional nystagmus test with an infrared CCD camera. In the infrared CCD camera test, nystagmus was detected in 20 cases (51%) among 39 patients without vestibular symptoms. In the ENG test, abnormal findings were detected in 24 cases (62%) among 39 patients without vestibular symptoms. Based on these findings, we therefore advocate that both cochlear and vestibular function tests should be performed in patient with sudden deafness even when they have not complained of vestibular-related symptoms.
