FUNCTIONAL AND HISTOLOGICAL-EVALUATION OF THE FACIAL-NERVE IN PATIENTS WHO HAVE UNDERGONE HYPOGLOSSAL-FACIAL NERVE ANASTOMOSIS AFTER REMOVAL OF CEREBELLOPONTINE ANGLE TUMORS

Facial nerve specimens removed from ten patients who underwent hypoglo ssal-facial nerve anastomosis for facial palsy following removal of ce rebellopontine angle tumors were studied histologically. Facial nerve function prior to the anastomosis surgery and the degree of postoperat ive functional recovery were compared with the histological results. T he recovery of facial palsy after the anastomosis surgery was excellen t or satisfactory in nine patients and the endoneurium within the nerv e fascicles was well-preserved. The recovery of facial palsy was poor in one patient who had severe fibrosis of the endoneurium. The histolo gical and ultrastructural features of the facial nerve were closely re lated to the occurrence of facial palsy prior to tumor removal, the st atus of the nerve after tumor removal, and the interval between tumor removal and anastomosis surgery. Based on these histological and funct ional relationships, the timing and indications for anastomosis surger y are discussed.