Vestibular schwannomas are benign tumours arising from the vestibulo-cochlear nerve. They are the commonest tumour of the cerebello-pontine angle at 80% and represent about 9% of all intracranial tumours. The St Vincent’s Department of Skull Base Surgery has a vast experience in the assessment and management of these tumours, and has an active role in ongoing prospective research in their management.
Natural history of growth is critically important in the formulation of a management paradigm.
Treatment algorithms include conservative surveillance, microsurgical removal employing either hearing conservation or hearing destructive approaches and radiotherapy. There have been increased reports on quality of life outcomes, as well as large series reporting complications, hearing and facial nerve conservation rates.
These figures show the varying sizes of tumours that are identified. The first image shows a small black mass within the internal auditory canal, through which the nerves of hearing and balance and the facial nerve travel from the brain into the ear itself. The second image shows that a tumour has extended outside this canal and is now occupying the cerebellopontine angle (CPA), coming close to the brainstem. The third image shows a tumour that has grown to the degree where there is compression of the brainstem.
As a general principal many small tumours as in the first image are initially monitored and intervention is made when and if growth can be documented, or if in specific circumstances a decision is made to attempt to preserve residual hearing. The size seen in the second image needs close observation, and consideration of early intervention. Certainly tumours at the size seen in the third image require interventional management soon after diagnosis.