Extended subtotal petrosectomy as a treatment for persistent cerebrospinal fluid (CSF) otorhinorrhoea is presented. Four patients were successfully operated on by this technique, all previously having undergone suboccipital removal of vestibular schwannoma: other interventions used had failed to seal the fistulae. The internal auditory canal was the usual pathway for CSF leakage as well as retrosigmoid, retrolabyrinthine, retro- or perifacial cells. Total exenteration of middle ear and mastoid cell tracts, skeletonization of sigmoid sinus, jugular bulb and facial nerve, drilling out of semicircular canals, vestibule, and cochlea, and skeletonization of the internal auditory canal, followed by obliteration, are the main steps of this approach.
