The Coronal Section Study of Computed Tomography in the Intracranial Invasion by Nasopharyngeal Carcinoma

The radiographic technics for the diagnosis of NPC (nasopharyngeal carcinoma) have been well established known as plain skull films, nasopharyngography and polytomography etc., but still not be satisfied to demonstrate the soft tissure involvement by the tumor, especially in the intracranial. The use of the coronal section study of computed tomography with the help of enhancement by contrast medium can make easier detect the brain invasion, particularly the lesion is near the brain base. In this series, it is often seen that direct bone destruction of middle cranial fossa, the sphenoid and the basioccipit etc. at the skull base as a main route of intracranial invasion by NPC. Sometimes, it may have not bone destruction, but the lesion can go through the foramina, fissures and jugular fossa etc. into the intracranial at the skull base. The intracranial involvement by NPC is in order of frequency the middle cranial fossa, the posterior cranial fossa and very rare the anterior cranial fossa. In this tudy, it is found that the dura is a very good barrier, the most intracranial lesions of NPC are just extradurafly involved. The coronal section study makes clear that the route of intracranial invasion as well as the relationship between the extracranial and intracranial components of the lesion, which is helpful for the therapeutic planning. In the mean time, it is the best way to evaluate the effect of the treatment and tumor recurrence.