Posterior petrous meningiomas: surgical classification and postoperative outcomes in a case series of 130 patients operated via the retrosigmoid approach.

There is a lack of standardized definition and classification of primary posterior petrous meningiomas (PPM), with consequent challenges in comparing different case series. The aim of our study is to provide an anatomical description and classification of PPM analysing a homogenous series of patients operated via retrosigmoid approach (RSA).