Residual tumour after vestibular schwannoma surgery

Objective: To evaluate residual tumour occurrence after vestibular schwannoma surgery, based on intra-operative registration and magnetic resonance imaging one year post-operatively. Methods: Patients undergoing translabyrinthine surgery for vestibular schwannoma in Denmark between 1976 and 2008 were registered in a national database covering 5.5 million inhabitants. Results: Translabyrinthine surgery was undertaken on 1143 patients. Of these, 978 had total, 140 near-total and 25 subtotal tumour excision, as assessed intra-operatively by the surgeon. One year after surgery, 65 per cent of small tumour remnants and 11 per cent of large tumour remnants were not visible on magnetic resonance imaging. The mean pre-operative size was significantly smaller for totally excised tumours, compared with neartotally and subtotally excised tumours. Revision surgery was performed for 14 patients (1.2 per cent), of whom 2 had received total, 5 near-total and 6 subtotal excisions initially. Conclusion: Most residual tumours disappear spontaneously, probably due to devascularisation. Few patients with a small residual vestibular schwannoma will require revision surgery or secondary radiotherapy.