SUDDEN DEAFNESS IN VESTIBULAR SCHWANNOMA

Twelve per cent of a series of 284 patients with vestibular schwannoma presented with sudden deafness. If sudden sensorineural hearing loss is present then it is very likely to be the main presenting symptom. T he mean length of patients' history is eight months shorter in this gr oup than in the non-sudden deafness group. Sixteen per cent of vestibu lar schwannoma patients without sudden deafness present with a 'dead' ear whereas 29.5 per cent of those presenting with sudden deafness hav e total hearing loss. There was no significant difference between the sudden deafness group and the 'all others' group with regard to tumour size, audiogram shape, caloric test, imbalance, and facial numbness. Although the numbers of patients with sudden deafness in this series w ere too small to reach significance, on the basis of the clinical corr elation of vestibular schwannoma morphology it is possible to postulat e that compression of the vasculature within the bony internal auditor y canal by a laterally arising tumour may be the aetiological factor a nd may be more likely to occur than in more medially arising tumours.