RELIABILITY OF DIAGNOSTIC PROCEDURES IN F ACIAL PALSY WITH SPECIAL REFERENCE TO MRI

Facial nerve palsy is commonly examined using a variety of topodiagnos tic and electrophysiological tests. More recently, MRI has also been u sed to study lesions of the facial nerve. Due to varying time interval s between the onset of symptoms and clinical examination, however, the diagnostic value of these procedures remains limited. In the present study, 30 patients with facial nerve palsy of diverse origin were exam ined with MRI (1.5 Tesla magnetom) using a special surface coil and 30 -degrees parasagittal slices of 3 mm thickness. These special modifica tions enabled us to visualize the nerve in its entire course through t he temporal bone. After the application of Gd-DTPA the enhancement of the contrast medium could be verified in all cases. A moderate enhance ment in the geniculate ganglion as well as in the labyrinthine segment correlated with a good prognosis in terms of complete restoration of facial nerve activity, while an increased enhancement correlated with a poor prognosis. Our results indicate that MRI is of superior diagnos tic value as compared to clinical and electrodiagnostic tests, at leas t in the patients we examined in this study. Still, further evaluation s are necessary to justify a possible routine clinical use of this pro cedure.