We welcome the comments made by Dagain et al. in their letter of response to our article. In particular, we note the similarity of their approach to our own with regards to cystic vestibular schwannomas in elderly patients with significant comorbidities.

We agree that cyst aspiration alone is unlikely to be sufficient and that a shunt will be required in most cases. In case 1 in our paper, intermittent reservoir aspirations did however allow us to gauge the clinical response to cyst drainage before proceeding to insertion of a distal catheter. Furthermore, we very much endorse the assertion that a valve-less system is required due to tumour fluid viscosity (in both the cases we described, a valve-less system was used with a reservoir for access).

We note with interest the description of the patient in whom the solid tumour increased significantly after drainage of the cystic component. This reaffirms our opinion that patients treated with this method require interval clinical and radiological assessment.

The emphasis placed on neuronavigation by Dagain et al. is very much in line with our clinical practice in this area: frameless stereotaxy was used in both of the cases described.

Cystoperitoneal shunting for cystic vestibular schwannomas is an extremely useful technique in specific circumstances. We thank the authors for their remarks and we await the publication of their own series with interest.