A new paradigm in facial reanimation for long-standing palsies?

Abstract

Background: A chance observation of return of excellent facial movement, after 18 months following the first stage of cross-face nerve grafting, without free functional muscle transfer, in a case of long-standing facial palsy, lead the senior author (RBA) to further investigate clinically.

Patients and methods: This procedure, now christened as cross-face nerve extension and neurotization, was carried out in 12 patients of very long-standing facial palsy (mean 21 years) in years 1996-2011. The mean patient age and duration of palsy were 30.58 years and 21.08 years, respectively. In patients, 1-5 a single buccal or zygomatic branch served as a donor nerve, but subsequently, we used two donor nerves. The mean follow-up period was 20.75 months.

Results: Successive patients had excellent to good return of facial expression with two fair results. Besides improved smile, patients could largely retain air in the mouth without any escape and had improved mastication. No complications were encountered except synkinesis in 1 patient. No additional surgical procedures were performed.

Conclusion: There is experimental evidence to suggest that neurotization of a completely denervated muscle can occur by the formation of new ectopic motor end plates. Long-standing denervated muscle fibres eventually atrophy severely but are capable of re-innervation and regeneration, as validated by electron microscopic studies. In spite of several suggestions in the literature to clinically validate functional recovery by direct neurotization, the concept remains anecdotal. Our results substantiate this procedure, and it has the potential to simplify reanimation in longstanding facial palsy. Our work now needs validation by other investigators in the field of restoring facial animation.

Keywords: Cross face nerve grafting; facial palsy; facial reanimation; neurotization.

Figure 1

Patient 1 (index case) - a 39 years male with right side Bell's palsy of 35 years duration. (a) preoperatively demonstrating extreme deviation of left oral commissure on movement (b) preoperative facial position in repose. Also showing right lagophthalmos (c) at first follow-up visit after 18 months of crossfacial nerve grafting. Patient is attempting to smile with obvious excursion of the right oral commissure. The gold weight in right upper eyelid is noticeable (d) a very symmetrical smile is maintained even after extra exertion (follow-up visit of 18 months)

Figure 2

Patient 2 - a 19 years girl with isolated palsy of left lower lip and commissure depressors of 5 year duration. (a) Perfect preoperative symmetry at rest (b) lower lip movement unmasking the palsy of left lower lip depressors (c) excellent symmetry seen at 12 months follow-up following cross-facial nerve grafting to left lower lip depressors

Figure 3

Patient 6 - A 36 years old priest with left-sided congenital facial palsy. (a) Lip asymmetry in repose (b) lack of any left-sided excursion on forceful smile. Severe lagophthalmos is also noticeable (c) at 15 months follow-up the patient shows improved symmetry of lips in repose. A gold weight placed to correct lagophthalmos can be noticed (d) at 40 months follow-up the patient shows excellent and perfect symmetry on smiling

Figure 4

Patient 12 - a 44 years old lady with left sided Bell's palsy of over 40 years duration. (a) preoperatively patient is showing some facial asymmetry in repose (b) gross asymmetry and lack of left-sided lip excursion is noticed when patient attempts to smile forcefully (she actually ends up grimacing instead of smiling because of distress) (c) at 30 months follow-up, the patient shows improved symmetry in repose (d) a happy patient with excellent symmetry on smiling at 30 months follow-up

Figure 5

A schematic sketch of the surgical plan to employ three crossface nerve grafts to harness the potential for complete restitution of all facial movements by neurotization