Sir: Facial transplantation has emerged as the next step on the reconstructive ladder for severe facial disfigurement, but functional recovery and return of facial sensation and motion will vary, be difficult to predict, and may take months or years.1,2 Motor recovery following composite tissue allotransplantation has been reported to be slower and often less optimal when compared with the sensory recovery outcomes.3–5 The facial appearance of the recipient improves gradually along with nerve regrowth, with changes in expression and the appearance of nasolabial folds. A kinematic preoperative evaluation may be important for further analysis of the results. A 22-year-old man with severe sequelae of thermal burns (55 percent total burn surface area), a candidate for facial transplantation, was analyzed with a novel quantitative method: facegram (Fig. 1).Fig 1: Male patient, 22 years old, with severe sequelae of thermal burns (55 percent total burn surface area).In order to reliably capture the dynamics of the smile movements, we developed specialized software capable of simultaneously tracking the position over time of a number of anatomical points (commissures, midpoints, and Cupid’s bow), using video recordings of the subject. The programing environment MATLAB (R2011a; MathWorks, Natick, Mass.) was used for computing the facegrams. The software provides a graphic user interface (GUI) to assist the user in different tasks, such as drawing a line setting the face’s vertical axis of symmetry or pointing and clicking on the colored dots marking the anatomical landmarks. The main element is the plot, in scale, of the paths followed by each anatomical landmark, as shown in Figure, Supplemental Digital Content 1,https://links.lww.com/PRS/A823. In every pathway, six points mark important times: T1, start of recording; T2, start of contraction; T3, end of contraction; T4, start of relaxation; T5, end of relaxation; and T6, end of recording; as shown in Figure, Supplemental Digital Content 2, https://links.lww.com/PRS/A824. The complete facegram includes four additional elements: the absolute horizontal (and vertical) displacements and the differential horizontal (and vertical) displacements of each landmark as a function of time. Facegram analysis in this patient revealed symmetry/balance and temporal consistency, despite the reduction in range of motion over time (Fig. 2). The hold period is not properly maintained (there is a progressive loss of extension). Vertical movement appears to be superior in relation to horizontal movement. The extension of the commissures is clearly superior to that of the midpoints or Cupid’s bow, which may be explained by cicatricial retraction of the central part of the patient’s lips.Fig 2: Facegram analysis shows symmetry/balance and temporal consistency. The hold period is not properly maintained (there is a progressive loss of extension). The extension of the commissures is clearly superior to that of the midpoints or Cupid’s bow.Muscles would regain motion through the facial nerve, and if this nerve was being dissected proximally to include all branches, regeneration would take a long time to enable muscular activity within the graft. Mobile facial expression also depends on the depth of scarring before the operation. There are then two possibilities: (1) the patient has a deformity so obvious that any degree of functional recovery after transplantation means a significant gain on facial expression, or (2) as in this patient, despite scarring caused by burns, it will be difficult to recover motor function that will achieve the same degree of muscle contraction. In this case, the facegram can provide a baseline pattern, which will be important to accompany functional recovery. PATIENT CONSENT The patient provided written consent for the use of his image. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article.
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