Neoplasie extracraniche responsabili di sindromi dei nervi cranici

Abstract

Aim of this study is to examine the different routes by which extracranial neoplasms can spread to the cranial cavity through cranial nerves. Sixty pts were retrospectively evaluated (38 males, 22 females, age between 16 and 85 years); they showed isolated or multiple cranial nerve deficit, with evidence of an expansive lesion responsible for the symptoms. Images were obtained by third generation, spiral CT scanners and medium and high field MRI. The different possible ways of diffusion, also coexistent in the same patient, are the following: – erosion of skull foramina and canals; – perineural, perivascular ascending spread through pterygopalatine fossa to orbitary apex, to cavernous sinus through oval foramen, through stylomastoid foramen to pyamid, to posterior fossa through its foramina; – direct compressive effect on neighbouring structures (mainly cranial nerves) in the neck region. A perfect knowledge of the anatomy of the skull base and neck regions is necessary to correctly plan and examine neuroradiologic images, which in their turn must be susceptible to clever and variable schedules according to the different conditions. Altogether these factors can help physicians in the optimal choice of therapeutic interventions and formulating prognosis.