Fluorescent findings of the facial nerve at decompression operation

Abstract

We performed decompression operation in cases of Bell's palsy, traumatic facial nerve palsy of the temporal bone and otogenic facial nerve palsy. At the time of decompression operation, a fluorescent flow in the facial nerve trunk was measured by means of the intravenous injection of a fluorescent substance which is used for the eyes fundus examination.The relation between prognosis and fluorescent flow were compared. Experimental studies were performed using the rabbits in orders to obtain basic information.The results were obtained as follows: In Bell's palsy, each 5 cases showed a fluorecence ranged from slight to well but there was no case of complete cure. However, there was a tendency of cure in cases with a good fluorescence. On the other hand, in traumatic and otogenic facial nerve palsy there were cases of complete cure although neither response in the maximal stimulation test nor fluorescence in the nerve.It is thought that there is a difference of pathophysiological condition between Bell's palsy and traumatic or otogenic facial nerve palsy.A fluorescent flow in the extratemporal portion of the facial nerve was seen from the distal side to the proximal side.On the contrary, in the intratemporal portion of the facial nerve it was seen from the proximal side to the distal side. Measurement of the fluorescent flow and neuropathological exmination of the facial nerve were made after the experimental nerve damage such as crush or incision. The milder nerve damage, the better fluorescence of the nerve trunk was seen. The regenerated nerve fibers showed a good fluorescence as well as normal nerve fibers.