Voluntary Smile Research Articles

Simultaneous Reconstruction of Voluntary and Spontaneous Smiles and Eyelid Closure With Triple Latissimus Dorsi Muscle Flaps.

Using the free latissimus dorsi muscle flap for dynamic reconstruction for established facial paralysis helps reconstruct various facial dysfunctions, depending on nerve and muscle arrangements. The authors divided the latissimus dorsi muscle into 3 flaps, 2 placed in the cheek area to reconstruct a "voluntary and spontaneous smile" and 1 fixed to the fascia implanted in the eyelid to treat lagophthalmos in a 1-stage procedure in a 61-year-old woman who underwent tumor resection for a left facial nerve schwannoma and developed complete facial paralysis. Fascia lata and free latissimus dorsi muscle grafting were performed. Spontaneous smile was reconstructed using the contralateral facial nerve as a motor source. Voluntary smile and eyelid closure were reconstructed using the ipsilateral masseter nerve, dividing the latissimus dorsi muscle flap into 3 muscle bodies. This procedure restored her smile and eyelid closure ability, with a nearly normal overall facial impression, making it a valuable technique for 1-term reconstruction of smiles and eyelid closure.

Considering Cuteness Enhances Smiling Responses to Infant Faces1,2

AbstractLaboratory and field research has reported that the appearance of infants causes observers to smile. The current study examined whether this smiling response is modulated by the observer's task and evaluative dimension. Thirty‐nine young nulliparous women were asked to rate the cuteness or beauty levels of 6‐month‐old infants' faces using a 7‐point scale in different blocks. Facial electromyograms (EMGs) were recorded of participants' facial muscles related to both smiling (the zygomaticus major [ZM] and orbicularis oculi [OO]) and frowning (the corrugator supercilii [CS]). The results showed that cuteness and beauty ratings were highly correlated with each other (r = .90), indicating that these evaluations were based on similar attractiveness‐related physical features. Facial EMG responses on the smiling muscle sites, ZM and OO, increased significantly from the baseline when participants rated the faces' cuteness, and the responses were larger than when participants rated the faces' beauty. CS activity was not found to have any effect. The perceived cuteness level of the infant faces did not affect the facial EMG responses. Moreover, the magnitude of the smiling response was shown to be much smaller than that associated with voluntary smiling. These findings suggest that facial expressions while viewing infant faces do not exhibit a fixed pattern but are modulated by observers' tasks and that considering cuteness, which is based on more affective evaluations than beauty, can enhance smiling responses.

Simultaneous Reconstruction of Smiling Eye Using V-Shaped Long Latissimus Dorsi Muscle Transfer in Patients with Flaccid Facial Paralysis.

Various neurovascular free muscle transfers for smile reconstruction in patients with facial paralysis have been reported. However, these methods focused on perioral smiling rather than eye smiling. Although the lower eyelid does not contribute significantly to eyelid closure, dynamic reanimation of the upward movement of the lower eyelid with bulging of the malar region during smiling is important in smile reconstruction. The authors present a novel procedure for smiling eye and perioral smiling. The V-shaped latissimus dorsi muscle flap containing the descending branch (DB) of the thoracodorsal nerve (TDN) was used. Muscle A (15 to 17 cm), which is located along the main trunk of the DB, is much longer than muscle B (10 to 12 cm), which is along the branch of DB. A distal stump of the TDN involved in muscle B was prepared. The true trunk and distal stump of the TDN were sutured to the contralateral facial and ipsilateral masseteric nerves, respectively. The central region of muscle A was positioned at the lateral part of the lower eyelid; the distal end of long muscle A was affixed to the temporal region, which enabled periocular movements and narrowing of the palpebral fissures alongside perioral smiling when muscle A contracted. Nine patients with complete flaccid facial paralysis were treated. All patients attained muscle contraction induced by the ipsilateral masseteric and contralateral facial nerves. The smiling eye appearance was observed in 7 of 9 patients. This procedure simultaneously improves paralytic ectropion at rest and aids eyelid closure and enables early voluntary smile and a later spontaneous smile.

Evidence-based Considerations on Donor Nerve Selection and Ideal Muscle Weight in Long-standing Facial Paralysis – The Freiburg Algorithm

Introduction: Free functional muscle transfer (FMT) is the standard for smile reconstruction in long-standing facial paralysis. Using the contralateral NVII for innervation of the transferred muscle frequently produces satisfying results. However, axon counts of facial nerve branches used as donor nerves for cross-face nerve grafts (CFNG) generally decrease with age resulting in insufficient muscle contraction. Also, the volume of the transferred muscle segment necessary for symmetric oral excursion depends on the donor nerve. This study presents our algorithm for donor nerve selection and ideal muscle weight in long-standing facial paralysis. Materials and Methods: In a prospective cohort study, we evaluated facial palsy patients scheduled for dynamic smile reanimation preoperatively via EMG for involuntary masseter muscle activation upon smiling. Six months after noting the first muscle contraction, we assessed smile synchronicity and correlated the results with the EMG results. Furthermore, we correlated oral commissure amplitude with the weight of the muscle segment and the donor nerve used. Results: We recruited 30 patients for the prospective study and included 22 patients in the retrospective analysis. Postoperatively, all patients demonstrated a voluntary smile. The preoperative coactivation of the masseter muscle predicted the outcome regarding synchronicity of the smile with high sensitivity and specificity. Also, we observed a significant increase in oral commissure excursion with increasing muscle weight when using the NV. Conclusion: The lack of masseter coactivation upon smiling predicts the absence of a synchronous, involuntary smile after FMT using the masseteric nerve. The ideal muscle weight depends on the donor nerve and should be smaller for the NV.

Comparison of static and dynamic symmetry between masseter-innervated and dual-innervated free multivector serratus anterior muscle transfer for complete facial paralysis

In this study, facial symmetry was compared between the masseter-innervated and dual-innervated free multivector serratus anterior muscle transfer (FMSAMT) methods. Eighteen patients with unilateral complete facial paralysis underwent facial reanimation surgery between April 2006 and July 2019. The masseter-innervated FMSAMT group (Group M, n=8) underwent end-to-end coaptation with the ipsilateral masseter nerve in one stage. The dual-innervated FMSAMT group (Group D, n=10) underwent end-to-end coaptation with the masseter nerve and end-to-side coaptation with the contralateral facial nerve via cross-face nerve graft. They were further divided into the one-stage (Group D1, n=5) and two-stage (Group D2, n=5) subgroups. The durations of periods until the first visible muscle contraction with clenching, first spontaneous smile, and the completion of resting tone were evaluated. The possibility of a spontaneous smile and symmetry of the midline and horizontal deviation at rest and during voluntary smiling were compared between each group. Groups M and D differed significantly in the possibility of a spontaneous smile and improvement rate of midline deviation and horizontal deviation at rest (p<0.001, p<0.001, and p=0.001, respectively) but not in the improvement rate of midline and horizontal deviation during voluntary smiling. The duration of the period until the completion of resting tone was significantly shorter in Group D1 than in Group D2 (p=0.048); however, the possibility of a spontaneous smile and the improvement rate of midline and horizontal deviation were not significantly different. Dual-innervated FMSAMT was effective in guaranteeing a symmetrical resting tone, voluntary smiling, and reproducing a spontaneous smile.

Facial reanimation using free partial latissimus dorsi muscle transfer: Single versus dual innervation method

The aim of the present study was to analyze the consequences of partial free latissimus dorsi muscle flap with nerve splitting technique (Partial LD transfer) for facial reanimation and compare outcomes according to innervation method (singer versus dual innervation).Patients with complete unilateral facial paralysis underwent either the single (ipsilateral masseteric nerve only) or dual (ipsilateral masseteric nerve plus contralateral buccal branch of the facial nerve) nerve innervation method for facial reanimation. An assessment was carried out to compare the outcomes between the single and dual innervation.Total of 21 patients were involved in this study. In the single innervation group, 7 out of 8 patients developed a voluntary smile. However, none were able to achieve a spontaneous smile. On the other hand, 9 out of 13 patients developed a voluntary smile and 3 out of 13 patients achieved a spontaneous smile. The mean increases of smile excursion assessed by Emotrics software and Terzis grades showed no significant differences between two groups.Within the limitations of the study it seems that partial LD transfer approach utilizing the dual innervation method has a positive effect on achieving a spontaneous smile and could be a valuable option for facial reanimation.

Efficacy of retrograde innervation through the distal stump of the thoracodorsal nerve in single-stage neurovascular latissimus dorsi transfer for facial reanimation: A retrospective analysis of 30 cases

The aim of the study was to analyze the efficacy of retrograde innervation of single-stage free latissimus dorsi (LD) flap for facial reanimation by the distal stump of thoracodorsal nerve (TDN).After the main trunk of TDN was split in half to preserve the function of transverse branch, the proximal stump was coapted with the contralateral facial nerve, and the distal stump was coapted with the ipsilateral masseteric nerve, or vice versa. The length of each nerve stump and the time required for voluntary and spontaneous muscle contraction after surgical treatment were reviewed.Among a total of 30 patients, there was no statistically significant difference in the successful recovery ratio of voluntary smile (antegrade, 86.7%; retrograde, 92.3%; p = 0.323) and of spontaneous smile (antegrade, 61.5%; retrograde, 100.0%; p = 0.079). There was no significant difference in the speed of nerve regeneration of voluntary smile (antegrade, 1.32 cm/month; retrograde, 1.14 cm/month; p = 0.213) and of spontaneous smile (antegrade, 0.91 cm/month; retrograde, 1.09 cm/month, p = 0.120).Within the limitations of the study, it seems that retrograde innervation of neurovascular muscle grafts has the potential to serve as a relevant alternative to other established options of neurovascular muscle transfer, because it provides comparable results in terms of rehabilitation success.

Advances and future directions in the care of patients with facial paralysis

Advances and future directions in the care of patients with facial paralysis

Outcomes of Facial Symmetry and Tone at Rest After Masseteric-to-Facial Nerve Transfer

Importance: Masseteric-to-facial nerve transfer has gained popularity as a technique that provides dynamic voluntary function in unilateral facial paralysis. Despite the multiple studies that have demonstrated its efficiency in restoring dynamic facial function, there is a paucity of data on the effects on facial symmetry and tone at rest. Objective: To evaluate facial symmetry and tone at rest after masseteric-to-facial nerve transfer in patients with unilateral facial paralysis. Design, Setting, and Participants: This is a retrospective review of patients undergoing masseteric-to-facial nerve transfer for unilateral facial nerve paralysis at a tertiary academic center from 2012 to 2016. Patient demographics, etiology and duration of facial nerve paralysis, intervention, and the electronic Facial Assessment by Computer Evaluation (eFACE) scores were analyzed. Intervention: Masseteric-to-facial nerve transfer. Main Outcomes and Measures: Resting facial symmetry and tone was graded preoperatively and postoperatively using eFACE. Results: The study included 11 patients with complete unilateral facial paralysis treated with masseteric-to-facial nerve transfer from 2012 to 2016. Postoperative eFACE scores across the dynamic midface and smile scores demonstrated a statistically significant increase compared with preoperative eFACE scores (p < 0.001). There was no statistically significant difference found between preoperative and postoperative static midface and smile eFACE scores. Conclusions: Masseteric-to-facial nerve transfer has demonstrated promising results in restoration of voluntary smile. However, it has little to no effect on resting facial symmetry and tone.

Masseteric-zygomatic nerve transfer for the management of eye closure-smile excursion synkinesis.

The purpose of this study is to illustrate the efficacy of masseteric-to-zygomatic nerve transfer to address eye closure-smile excursion synkinesis after facial nerve paralysis. Synkinesis after facial nerve paralysis represents a wide range of facial movement disability. One manifestation is involuntary smiling with eye closure and a concomitant reduction of oral commissure movement with attempted smile ("frozen smile") - arising as a result of aberrant fibers populating the zygomatic branch-muscle complex. This is a particularly difficult area to treat with conservative management. We propose a single-stage procedure to sever the dysfunctional zygomatic nerve and perform a masseteric-zygomatic nerve coaptation to recover a voluntary smile. We present a case series of eight patients with eye closure/smile excursion synkinesis who underwent single-stage masseteric-zygomatic nerve transfer by a single surgeon. The surgical technique and indications for surgery were reviewed. Patients underwent facial movement analysis using Emotrics. We analyzed the pre- and post- surgical photographic images of 8 patients with synkinesis (7 female, 1 male). Masseteric-facial nerve transfer was performed from 18months to 22years after the initial facial paralysis. Eyelid and brow positioning were more symmetric after surgery, with discrepancy between affected and unaffected side decreasing from 2.1 to 1.0mm (p<.05) and 1.74 to 1.29mm (p<.05), respectively. Symmetry of smile excursion postoperatively was also improved with commissure excursion discrepancy decreasing from 8.8 to 3.78mm (p<.05). Discrepancy in the smile angle when comparing affected to unaffected side improved postoperatively from 10.3 to 5.2 degrees (p<.05). Improvement in oral commissure height was noted, but not statistically significant. The masseteric-zygomatic nerve transfer is a useful technique for the treatment of eye closure/smile excursion synkinesis after failure of chemodenervation and/or physical therapy.

Kinematic Analysis of Smiles in the Healthy Pediatric Population Using 3-Dimensional Motion Capture.

Facial normalcy, as measured with 2-dimensional or 3-dimensional photographs, has been documented in the healthy pediatric population. However, static images convey far from a complete representation of an individual's daily interactions with peers. Craniofacial surgery induces changes to soft or osseous tissues and thereby affects dynamic facial expression. To-date, there has not been rigorous, dynamic quantification of normal facial expression. In this study, we used 4-dimensional (4D) imaging to assess the facial expression of healthy children to provide a normative reference point for craniofacial surgeons. A total of 36 healthy pediatric volunteers underwent 4D video recordings while performing a maximal voluntary smile. A face template containing 884 landmarks was registered and tracked throughout the videos using Dimensional Imaging software. Participants were divided into 2 smile groups: open-lip smile and closed-lip smile. Kinematic analysis of smiles was calculated for every landmark from its position in the resting frame to its terminal displacement. Composite smiles and Euclidean distance maps were generated displaying areas of greatest displacement near the oral commissures. There was significant difference between closed-lip and open-lip groups in regions of eyes and cheeks. In addition, the open-lip smile group demonstrated significantly greater displacement in the oral commissure on the left side compared to the right (P < .05); whereas, in the closed-lip group, the eyes and cheeks moved significantly more on the right side. This study presents an innovative method that can be used to evaluate facial expressions to help craniofacial surgeons restore functional movement in patients with facial anomalies.

Patient experience in nerve-to-masseter-driven smile reanimation

IntroductionThe nerve-to-masseter is one of the most frequently used neural sources in smile reanimation surgery. Very little information has been reported on patient experience with regard to reanimated smile usage and sequelae following transfer. The aim of this study was to quantify patient perception of nerve-to-masseter use in smile reanimation surgery. MethodsAn online questionnaire was developed based on the clinical expertise of our team, patient interviews, and existing questionnaires of facial palsy-related quality of life and temporomandibular joint dysfunction. All patients treated with nerve-to-masseter-driven smile reanimation surgery, both nerve transfers and muscle transplantations, between 2007 and 2016 with a valid email address were invited to participate. ResultsOf 171 operated patients, 122 with a valid email address were invited to participate. Seventy-one patients responded (63.4% female, mean age 51.1 years) after a median follow-up of 3.8 years. A voluntary smile while biting down at least “most of the time” was reported by 83.1% of patients; 46.5% reported ability to smile on the affected side without bite. A “normal” or “almost normal” spontaneous smile was reported in 23.9% of patients. A total of 18.3% of patients self-reported masseter muscle atrophy, and 1.4–14.1% reported temporomandibular joint dysfunction. Forty-one patients (57.7%) reported prandial movement of the face at least “most of the time,” with 9 patients (12.7%) considering this bothersome. ConclusionPatients report good voluntary smiling ability following nerve-to-masseter-driven smile reanimation surgery, with low rates of sequelae.

Pre-operative masseter muscle EMG activation during smile predicts synchronicity of smile development in facial palsy patients undergoing reanimation with the masseter nerve: A prospective cohort study✰

Synchronicity of the oral commissure movement of a bilateral smile is a significant goal for reconstruction in facial reanimation and may only be guaranteed with use of the facial nerve as a donor nerve. Yet over the years several studies report some degree of spontaneity in certain patients when using a non-facial donor nerve, which indicates that synchronous initiation of the smile might be achievable with other donor nerves. We designed a prospective cohort study to evaluate whether pre-operative involuntary activation of the masseteric nerve during smile predicts development of a synchronous smile development when using the masseteric nerve for reanimation. In a prospective cohort study unilateral long-standing facial palsy patients scheduled for dynamic smile reanimation with a free functional muscle transplant using the masseteric nerve as a donor nerve were preoperatively evaluated via EMG for involuntary activation of the masseter muscle upon smiling, which we called coactivation. Postoperatively, six months after noting the first muscle contraction smile synchronicity was evaluated. We analyzed the synchronicity of the bilateral smile development by analyzing slow-motion video sequences of the patients that were taken while the patients were watching funny video sequences. Results were then correlated with the pre-operative EMG. 30 patients were recruited for this prospective study and underwent facial reanimation surgery with a free gracilis transfer innervated by the masseteric nerve. 19 patients demonstrated involuntary coactivation of the masseter muscle upon smiling and 11 did not. Postoperatively all patients could demonstrate a voluntary smile. 94% of patients who had preoperative coactivation showed a synchronous movement of the oral commissure when smiling. In those patients, that did not show activation of the masseter muscle upon smiling 0% showed synchronicity. The preoperative coactivation of the masseter muscle is able to predict the outcome regarding synchronicity of the smile with a sensitivity of 99.7%, a specificity of 88.5% and 92.5% positive predictive value and 99.6% negative predictive value (p<0.001 for all). The lack of masseter co-activation with smile predicts a lack of spontaneous involuntary smile after dynamic smile reconstruction using the masseteric nerve.

Investigation of the activation of the temporalis and masseter muscles in voluntary and spontaneous smile production

Masticatory muscles or their nerve supply are options for facial reanimation surgery, but their ability to create spontaneous smile has been questioned. This study assessed the percentage of healthy adults who activate the temporalis and masseter muscles during voluntary and spontaneous smile. Healthy volunteer adults underwent electromyography (EMG) studies of the temporalis and masseter muscles during voluntary and spontaneous smile. Responses were repeated three times and recorded as negative, weakly positive, or strongly positive according to the activity observed. The best response was used for analysis. Thirty healthy adults (median age: 34 years, range: 25-69 years) participated. Overall, 92% of the masseter muscles were activated during voluntary smile (22% strong, 70% weak). Seventy-seven percent of the masseter muscles were activated in spontaneous smile (12% strong, 65% weak). The temporalis muscle was activated in 62% of responses in voluntary smile (15% strong, 47% weak) and in 45% of responses in spontaneous smile (13% strong, 32% weak). No significant difference was found for males vs females or closed vs open mouth smiles. There was no significant difference in responses between voluntary and spontaneous smiles for the temporalis and masseter muscles, and their use in voluntary smile did not predict activity in spontaneous smile. Our study has shown that masseter and temporalis are active in a high proportion of healthy adults during voluntary and spontaneous smiles. Further work is required to determine the relationship between preoperative donor muscle activation and postoperative spontaneous smile, and whether masticatory muscle activity can be upregulated with appropriate training.

Cranial Nerve Coactivation and Implication for Nerve Transfers to the Facial Nerve.

In reanimation surgery, effortless smile can be achieved by a nonfacial donor nerve. The underlying mechanisms for this smile development, and which is the best nonfacial neurotizer, need further clarification. The aim of the present study was therefore to further explore the natural coactivation between facial mimic muscles and muscles innervated by the most common donor nerves used in smile reanimation. The study was conducted in 10 healthy adults. Correlation between voluntary facial muscle movements and simultaneous electromyographic activity in muscles innervated by the masseter, hypoglossal, and spinal accessory nerves was assessed. The association between voluntary movements in the latter muscles and simultaneous electromyographic activity in facial muscles was also studied. Smile coactivated the masseter and tongue muscles equally. During the seven mimic movements, the masseter muscle had fewer electromyographically measured coactivations compared with the tongue (two of seven versus five of seven). The trapezius muscle demonstrated no coactivation during mimic movements. Movements of the masseter, tongue, and trapezius muscles induced electromyographically recorded coactivation in the facial muscles. Bite resulted in the strongest coactivation of the zygomaticus major muscle. The authors demonstrated coactivation between voluntary smile and the masseter and tongue muscles. During voluntary bite, strong coactivation of the zygomaticus major muscle was noted. The narrower coactivation pattern in the masseter muscle may be advantageous for central relearning and the development of a spontaneous smile. The strong coactivation between the masseter muscle and the zygomaticus major indicates that the masseter nerve may be preferred in smile reanimation.

Paralysie faciale chez l’enfant

Facial palsy (FP) in children is congenital or acquired. When present at birth (congenital), etiologies are mostly traumatic and rarely developmental. Acquired FP needs investigation. Research on the etiology helps to determine prognostic and treatment. At most times, no specific cause is found. Treatment of idiopathic FP consists of early oral corticosteroid therapy and ocular protection. Treating the sequelae is essential and the physician has to consider the dynamic balance of both sides of the face. Dynamic rehabilitation should mainly concern the inferior facial third. We recommend the lengthening temporalis myoplasty (LTM). This relevant technique ensures replicable and reliable results with a harmonious smile. Facial dynamic rehabilitation after surgical procedure (muscle tranfer or free muscle flap) must be directed toward control of voluntary movement, to move from a mandibular smile to a spontaneous and voluntary smile, thanks to brain plasticity. Furthermore, botulinum toxin is well tolerated and remains a great tool to treat a child who can support injections.

Assessment of functional outcomes of temporalis muscle transfers for patients with longstanding facial paralysis.

Usually, clinical evaluation of facial reanimation provides accurate information about contraction of the mimetic muscles and phonation but fails to identify smile recovery and to quantify the motility of the lower third of the face during a smile. The purpose of this study was to verify that, in longstanding facial palsy, the modified temporalis muscle transfer (MTMT) can result in the ability to smile, not only voluntarily with chewing, but also spontaneously with a sudden emotional stimulus, and to confirm that a symmetric smile can be obtained. Ten patients of the treated group (group T; 4 women and 6 men) were randomly selected from a population of 24 patients with longstanding facial palsy treated by MTMT. Five normal subjects of the control group (group C; 3 women and 2 men) were enrolled as the control population. Functional outcomes after transposed temporalis muscle were examined and measured through clinical assessment by using a scored smile symmetry grading system, video recording, and surface electromyography (sEMG). In addition, the voluntary smile test (VST) and the not-voluntary smile test (NVST) were performed to study voluntary and spontaneous smiling. Subjects in the VST group (group T) were able to smile voluntarily and the expression was characterized by symmetry. In the NVST group, they were able to smile spontaneously and the symmetry of the smile was maintained for 8 subjects and only partially for 2 subjects. During both tests, the temporalis muscle of the treated side and the orbicularis oris muscle of the not-treated side were activated during smiling, indicating spontaneous activity of the transposed temporalis muscle with an emotional stimulus. For the control group, smiles during VST and NVST were symmetric and the temporalis muscles were not activated during smiling, whereas the orbicularis oris muscles were. Our study shows that the Morrison MTMT is able to restore the voluntary smile ability. Particularly, this technique allows for recovery of the spontaneous smile with symmetry. This assessment would seem to suggest that the transposed temporalis muscle might adapt from a chewing to a mimetic muscle. © 2016 Wiley Periodicals, Inc. Head Neck 38: E1535-E1543, 2016.

La myoplastie d’allongement du muscle temporal : raffinements techniques

First described by Labbé in 1997, the lengthening temporalis myoplasty (LTM) ensures the transfer of the entire temporal muscle from the coronoid process to the upper half of the lip without interposition of aponeurotic tissue. Thanks to brain plasticity, the temporal muscle is able to change its function because it is entirely mobilized towards another effector: the labial commissure. After 6 months of speech rehabilitation, the muscle loses its chewing function and it acquires its new smiling function. We describe as far as possible all the technical points to guide surgeons who would like to perform this powerful surgical procedure. We show the coronoid process approaches both through an upper temporal fossa approach and a lower nasolabial fold approach. Rehabilitation starts 3 weeks after the surgery following a standardized protocol to move from a mandibular smile to a voluntary smile, and then a spontaneous smile in 3 steps. The LTM is the main part of a one-stage global treatment of the paralyzed face. It constitutes a dynamic palliative treatment usually started at the sequelae stage, 18 months after the outcome of a peripheral facial paralysis. This one-stage procedure is a reproducible and relevant surgical technique in the difficult treatment of peripheral facial paralysis. An active muscle is transferred to reanimate the labial commissure and to recreate a mobile nasolabial fold.

One-stage dual latissimus dorsi muscle flap transfer with a pair of vascular anastomoses and double nerve suturing for long-standing facial paralysis

Various types of neurovascular free-muscle transfers have been reported as surgical treatments for long-standing facial paralysis. Among one-stage methods, two approaches, that is, latissimus dorsi transfer with nerve suturing to the contralateral facial nerve and gracilis transfer with nerve suturing to the ipsilateral masseteric nerve, have recently become popular. The former method has the advantage of making spontaneous smiling possible, but the contraction strength of the transferred muscle varies, whereas the latter approach has the advantage of guaranteeing voluntary contraction of the transferred muscle, but makes spontaneous smiling difficult. Recently, dual innervation methods have also been reported, but uncertainty remains about the utility of such approaches. To overcome these drawbacks, we devised a hybrid method combining the two previously established techniques. Two latissimus dorsi muscle flaps containing the thoracodorsal vessels from one side are transferred with a pair of vascular anastomoses. The true trunk of the thoracodorsal nerve, which innervates one of the muscle flaps, is sutured to the contralateral facial nerve, while the short branch of the thoracodorsal nerve, which innervates the other muscle flap, is sutured to the ipsilateral masseteric nerve. From November 2011 to October 2013, we used this method in four patients with long-standing facial paralysis. Smiling was assessed in the three patients who were followed up for more than 1 year, and satisfactory results were obtained (Harii score: 4-5). In one patient, the movement mediated via the contralateral facial nerve was a little weak, but this was compensated for by the muscles controlled by the ipsilateral masseteric nerve. Our novel one-stage method, which involves a combination of two previously established methods, guarantees early voluntary smiling, and spontaneous smiling becomes possible later. In addition, it is free from the uncertainty associated with double innervation and does not require nerve grafts. So, stable results can be expected in most patients with long-standing facial paralysis.

Double innervated free functional muscle transfer for facial reanimation

Background: The treatment of long-standing facial palsy represents a challenge for the reconstructive surgeon. Treatment is based on dynamic procedures such as functional muscle flaps. The benefit of added axonal load has recently been reported. This study describes a two stage technique involving dual innervation of a gracilis muscle flap with initial cross-facial nerve graft (CFNG) followed by free muscle transfer co-apted to both the CFNG and a masseter nerve for facial reanimation. Methods: A total of nine patients from August 2008–July 2011 were operated on with the double innervated gracilis muscle flap. Pre- and postoperative electromyography was documented, and video analysis with the five-stage classification of reanimation outcomes was performed. Results: All patients recovered voluntary and spontaneous smile abilities, with an average of 70% motor unit recruitment. Based on the Terzis reanimation outcome classification, four patients had an excellent result, four good, and one moderate. Conclusions: The double innervated gracilis muscle flap is a viable technique for the treatment of long-standing facial palsy. It enables a fast recovery with fast muscle activity, and allows an emotional smile and aesthetic symmetry.