Diagnosis and treatment of trigeminal schwannomas extending into both the middle and posterior cranial fossa

摘要

Trigeminal schwannomas (TSs) account for 0. 1% -0. 4% of all intracranial tumors and 1% -8% of intracranial schwannomas. Yoshida and Kawase classified TSs into 6 types according to their locations: M (TS involving the middle cranial fossa), P (TS involving the posterior cranial fossa), E (TS located at extracranial space), MP (TS involving both the middle and the posterior cranial fossa), ME (TS involving the middle cranial fossa and the extracranial space), and MPE (TS involving the the middle and the posterior cranial fossa and the extracranial space). Of these types, MP is the commonest, but is difficult to be totally removed. Between January 1984 and June 2003, we surgically treated 28 patients with TSs of type MP and obtained satisfactory results. To make a correct diagnosis of TS, to select appropriate surgical approach, and to improve surgical outcome of TS of type MP, we analysed the related clinical data and experiences.