Teaching Case

Patient with a long history of "sinusitis" developing a cavernous sinus syndrome

Long lasting signs of chronic sinusitis, developing signs of cavernous sinus syndrome with motor ocular disturbances and retro-orbital pain on the right. A MRI is done; T1W SE images before and after Gd injection are shown. Could you stage this tumour, and give the most probable way(s) of intracranial extension, if any ?

This is a huge tumour developed from the posterior part of the right maxillary sinus and invading the masticator space, including the pterygo-palatine fossa. The tumour enhances smoothly with subtle inhomogeneous character. The skull base is also invaded and there is certainly an invasion trough the foramen ovale, to the right cavernous sinus, the cavum of Meckel, and the anterior part of the right temporal fossa. There is also an infiltration of the superior orbital fissure and the apex of the orbit, as the posterior ethmoid cells on the right. Massive extension to the skull base is probably both perivascular and perineural. Note that there is a sequel of a right inferior turbinectomy. This tumour is obviously a T4 stage. This is an illustration of the degree of extent these lesions of the paranasal sinuses may sometimes reach before the diagnosis is done.