To the Editor: The acceptance of a partial face allograft asa promising procedure for patients with facial disfigurementwill depend on long-term functional results. An impressive recoveryof sensory function was reported by Dubernard et al. (Dec. 13issue).1 This recovery of sensory function is understandable,given that the maxillary and mandibular nerves were resuturedin the recipient's face. The recovery of motor function, however,remains a mystery, since only a single branch of the facialnerve (described by Dubernard et al. as "the inferior branchof the left facial motor nerve") was resutured. Such a nervebranch does not exist in the human facial nerve. Moreover, theauthors do not explain why a circumscribed reanimation on theleft side of the lower face would lead to recovery of motorfunction on both sides of the midface as well as the right sideof the lower face. The video does not provide a convincing explanation.Perhaps what we see in the video is just passive movement inthe transplanted tissue due to the sutures holding the graftmuscles to the conserved muscles of the recipient. The authorsshould present electromyographic data to document active movementin the graft. Without an active nerve supply, the graft musculaturewill undergo progressive atrophy.
Orlando Guntinas-Lichius, M.D. Friedrich Schiller University Jena D-07740 Jena, Germany orlando.guntinas{at}med.uni-jena.de
References
Dubernard J-M, Lengelé B, Morelon E, et al. Outcomes 18 months after the first human partial face transplantation. N Engl J Med 2007;357:2451-2460. [Free Full Text]
The authors reply: We surmise that the recovery of muscle functioninside the face graft occurred mostly through a phenomenon ofintramuscular innervation along the multiple bilateral sitesof muscular anastomoses and not through axonal regenerationarising from the single, small nerve anastomosis that was performedon the lower left part of the transplant. All depressor muscleson the lower face had been avulsed completely, along with theright and left mandibular (or inferior marginal) branches ofthe facial nerves. We repaired the nerves on the left side ofthe face with the aim of reanimating the lower lip and the chinbut could not do the same on the right side because the thincorresponding nerve was absent in the graft.1 Early in the postoperativeperiod, dynamic motions in the face graft were apparently dueto contractions arising from the recipient's remaining musclebellies, transmitted to the homologous allogeneic muscles towhich they were connected. We speculate that as intramuscularinnervation progressed, motor-nerve ingrowth through anastomosesof the levator muscles resulted in secondary dynamic expressivemotions, involving the midface muscle segments from the donor.Restoration of complete lip occlusion probably occurred as aresult of both intramuscular innervation of the upper part ofthe orbicularis oris muscle and intraneural axonal regenerationinside its lower sling.
We also wish to clarify our statement in the Methods sectionregarding consent. We noted that the patient gave her consentfor the face transplantation; we wish to add that she also gaveher consent for publication of the manuscript and for developmentand release of the accompanying video.
Jean-Michel Dubernard, M.D., Ph.D. Université Lyon 1 69473 Lyon, France
Previous
