Intra-Oral Vascularized Cross-Facial Nerve Grafts in Early Flaccid Facial Palsy: A Five-Year Review of Clinical Practice.

Abstract

An unanswered question in facial reanimation surgery is how to improve the results of conventional primary cross-facial nerve grafts. In this study, we designed a study to determine whether vascularizing cross-facial nerve grafts with shorter lengths following intra-oral insets, provides sufficient neural input to the targeted smile-mimetic muscles without the need for a concomitant "babysitter" procedure. In a retrospective review of practice over 5 years on facial palsy patients with smile asymmetry, we performed a combination of the intra-oral vascularized nerve graft (VNG) which connects the buccal branches of the facial nerve, that supply the smile-mimetic muscles, on either side of the face; the "Koshima-type" procedure. This VNG is performed in combination with a forked fascicular transfer of the masseteric nerve, which is coapted to the zygomatic branches of the facial nerve (Group I). In Group II, only the "Koshima-type" procedure was performed without a "babysitter" procedure, which only connected the buccal branches of the facial nerve on either side (Group II). Both approaches were statistically compared in cases of acute facial palsy (within 24 months of onset), in those with no pre-existing synkinesis. Statistical analysis was performed using the Mann-Whitney test. Of a total of 13 patients in the overall cohort; seven in Group I and six in Group II, there was a significant improvement in both groups in terms of an open mouth smile following surgery (p < 0.001), with no statistically significant difference between them (p = ns); but in terms of snarl movement, only patients in Group II showed significant improvement in upper lip elevation (p < 0.05). The "Koshima-type" procedure alone is sufficient in providing optimal and spontaneous smile reanimation, without the need for a "babysitter" procedure, provided it is performed within 24 months in facial palsy patients with no clinical or neurophysiological evidence of reinnervation.