Many diagnostic tools have been used to diagnosis and predict the prognosis of facial paralysis. Recently, magnetic resonance imaging has led a major advance in diagnostic imaging of facial paralysis. Gd-DTPA enhancement, especially, the only occurs in the area of inflammation, edema and tumors. Thus we can detect the site of lesion and cause of facial paralysis. Thirteen patients with clinical diagnosis of Bell's palsy and four with Herpes zoster oticus had MRI scans with Gd-DTPA agent. Enhanced segments were visible in eleven(85%) of Bell's palsy patients and all of Herpes zoster oticus patients. The most consistent area of enhancement in both disorders involved the geniculate ganglion and tympanic segment. There was significant correlation between the intensity or pattern of facial nerve enhancement on the images, the severity or duration of disease, topodiagnosis or prognosis of recovery. But, Gd-DTPA enhanced MRI does have a place in detection of site of lesion and presence of occult tumors.
|