2002 Volume 12 Issue 2 Pages 86-90
Thanks to development of computed tomography (CT) and magnetic resonance imaging (MRI), preoperative informations of middle ear disease are more and more increasing in recent years. Especially, development of multi-slice CT clearly demonstrates 3D reconstruction of ossicules and temporal bone fracture, which enable us to diagnose middle ear malformation and site of temporal bone injury. On the other hand, diagnosis of recurrent cholesteatoma is still difficult even by both CT and MRI, because tissue contrast and enhancement are similar to those of surroundinjg connective tissue and granulation.
MRI has been useful in facial nerve disorders. With use of gadolinium enhancement (Gd-MRI), lesion of the disease is clearly demonstrated, which makes differential diagnosis of viral etiology and others. The mechanism of contrast enhancement of the facial nerve by Gd is thought to relate to the disruption of the blood-nerve barrier as result of inflammation. However, it is still difficult to differentiate from Bell's palsy to Ramsay Hunt syndrome, because patterns of Gd enhancement in both disease is very similar.
Moreover, there is little information between Gd-MRI findings and severity or prognosis of facial palsy. A reliable and widely available imaging for early identification of Bell's palsy and Ramsay Hunt syndrome as well as early prediction of facial nerve recovery must be developed as soon as possible.
