We developed a split hypoglossal-facial nerve anastomosis procedure called hemihypoglossal nerve transfer for the treatment of facial paralysis.
Thirty-seven patients, most of whom developed facial paralysis after the removal of an acoustic neurinoma, underwent this procedure. The average period of paralysis was 6.3 months before surgery, and all the patients were followed up for >8 months. Except for 1 patient who had infection of the cheek, all patients recovered facial expression, regardless of the choice of side, cranial or caudal, of the split, hypoglossal nerve. A poor success rate was observed when the ansa cervicalis branch was used.
A few instances of tongue atrophy were observed; there were 17 patients with minimal tongue atrophy and 15 patients with moderate tongue atrophy. However, severe atrophy, causing functional deficit of the tongue, was not observed.
Thus, split hypoglossal-facial nerve anastomosis resulted in good constant facial reanimation. The choice of side, cranial or caudal, of the split hypoglossal nerve did not affect the facial reanimation outcome or tongue atrophy.
