Imaging tumours and pseudo-tumours of the ear

CT and MRI are in most of the cases associated in imaging of tumours and ps eudo-tumours of the temporal bone. The tumours of the external auditory mea tus particularly the malignant ones are rare. It is of a great interest to delineate a possible extension to the chorda tympani. Secondary cholesteatoma are the most frequent pseudo-tumours of the middle ear: CT and MRI evaluate very well their extension particularly in the gian t forms. Others tumours like tuberculosis, histocytosis, primitive cholesle atoma, tympanic glomic tumours may be diagnosed by imaging as well as the n euroma of the facial nerve, the meningioma or some rarer lesions as the ade noma, or the carcinoid tumour of the middle ear. The adenoma of the endolymphatic sac is the only true tumour of the membran ous labyrinthe whose diagnosis is nicely made by MRI. The primitive cholest eatoma, the neuroma of the facial nerve may reach the labyrinthine bone and are easily diagnosed by imaging which generally speaking is very good in e valuating the kind of pathology of each cavities, delineating the extension of the lesions and orientating the surgical procedures.