The foramen lacerum--a route of access to the cranial cavity for malignant tumours below the skull base.

Thirteen malignant neoplasms (seven different tumour types) arising in the postnasal space or surrounding soft tissues extended upwards through the skull base into the middle cranial fossa. Gadolinium-enhanced magnetic resonance imaging (GdMRI) clearly revealed the route of the tumour into the cavernous sinus, parasellar region and floor of the middle cranial fossa. Since this extension alters both management and prognosis, GdMRI in the coronal plane is a necessary investigation for persistent and unexplained facial pain in order to demonstrate such lesions of the trigeminal nerve. Differentiation between neoplasms and aggressive inflammatory disease may be difficult.