Objective: To avoid misdiagnosis and misapplied therapy of acoustic neuroma.
Methods: 92 cases of acoustic neuroma treated between 1983 and 1997 were retrospectively reviewed. Among them, 20 patients (21 ears, 21.7%) presented with sudden hearing loss as the starting symptoms. The diagnosis was based on audiological and radiologic examinations.
Results: The clinical and audiological analysis demonstrated that 57.1% of the ears showed hearing loss over 71 dBHL, and all ears had deteriorated ABRs. Acoustic reflex was nonreactive in all 10 ears tested. Positive findings in CT scan were 88.89%. CT pneumoencephalography or MRI provided useful information of diagnosis in those with negative findings of place CT scan.
Conclusion: ABR should be used as a routine test for patients with sudden deafness. When ABR was abnormal, CT scan around the internal auditory meatus was needed.