Cross-face Graft Research Articles

"Muscle foreshortening after free gracilis transfer for smile: Where, when, why?"

Gracilis free muscle transfer (GFMT) remains the standard for smile restoration in patients with long-standing facial palsy. Resting oral commissure lateralization (ROCL) following GFMT is aesthetically unappealing and can cause functional problems including dysarthria and oral incompetence. The risk factors for ROCL following GFMT are poorly understood. Of all patients who underwent GFMT for smile restoration from 2003 - 2021, patients with subsequent ROCL were identified from a facial nerve database using pre-determined search criteria. Medical records were reviewed to identify potential risk factors for muscle foreshortening. Of 412 patients who underwent successful GFMT since 2003, we identified 41 (10%) patients who subsequently developed ROCL. ROCL rates varied significantly based on gracilis innervation source, with ipsilateral CN VII innervation and dual-innervation (cross-facial nerve graft (CFNG) plus ipsilateral nerve-to-masseter (NTM)) demonstrating the highest foreshortening rates (27.3% and 15.4%, respectively), compared to the lowest rates of foreshortening when gracilis was innervated by CNFG alone (3.2%), p=0.005. Patients with a history of radiation to the surgical field were significantly more likely to develop ROCL (22%) compared to those without a history of radiation (8.6%), p<0.001. Furthermore, the rate of ROCL was significantly higher among patients who underwent concurrent stabilization of the nasolabial fold using a wide band of fascia lata (20.8%) compared to those who did not (6.6%), p<0.001. Herein we report potential risk factors for ROCL following GFMT for smile restoration, including innervation source, radiation history, and concurrent fascia lata static suspension.

The effect of increasing motor end-plate innervation on smile activation in acute and early facial palsy.

While it has been over half a century since primary cross-facial nerve grafting was first described for facial reanimation, the outcome of this procedure, remains inconsistent and provide lesser smile excursion when compared to the likes of the masseteric nerve. However, the latter itself has limitations in terms of the lack of spontaneity and resting tone. While combinations have been attempted more proximally, we ask the question as to whether more distal nerve transfers with vascularized nerve grafts are a better option. In a retrospective review of clinical practice at our institute, 16 consecutive patients had single, double, and finally triple distal nerve transfers, close to the target facial muscle to reinnervate the motor endplates directly, over a 6-year period (2018-23). All patients had the onset of facial palsy within 18 months. Statistical analysis of the comparison between three sub-cohorts was performed using student's t-test and one-way ANOVA, respectively. Qualitatively, masseteric neurotization of a single facial nerve branch translated into smile improvement in 50% of cases, as opposed to all cases of double- and triple-neurotization of the smile muscles. In terms of upper lip elevation, single neurotization showed improvement in 25% of cases, double-neurotization in 40% of cases and triple-neurotization in 100% of cases. Upper lip elevation was also significantly better in those who had a vascularized cross-facial nerve graft (Student's t-test <0.05). In summary, increasing neural input to the motor endplates of smile muscles can significantly improve smile activation, in acute flaccid facial palsies.

Cross-Facial Nerve Grafting Used Independently in Facial Reanimation: A Narrative Review

Cross-Facial Nerve Grafting Used Independently in Facial Reanimation: A Narrative Review

Electrophysiological Changes in Patients with Postoperative Cross-facial Nerve Graft in a Tertiary Care Center.

Facial nerve palsy is a multifaceted pathology that causes facial disfigurement, affecting eye closure, speech articulation, oral competence, and emotional expression, with functional, aesthetic, and psychological consequences. Standardized electrophysiological tests, such as electroneurography and electromyography, allow an objective evaluation of the functional state of the nerve. Here, we aimed to compare and correlate clinical findings with electromyography in patients with facial nerve palsy, before and after facial nerve reanimation with cross-facial nerve grafts. Eight patients with traumatic or nontraumatic facial paralysis with complete clinical records who underwent surgical reanimation of facial nerve with cross nerve grafts. The median time from diagnosis to treatment was 173 days (interquartile range = 222). Outcomes were evaluated using standard clinical scales (House-Brackmann, Sunnybrook, and eFACE) and electromyography. The median time for postoperative outcome evaluation was 768 days (interquartile range = 1053). A statistically significant difference was found between pre- and postoperative outcomes according to eFACE (Δ median = 13, P = 0.003), House-Brackmann (Δ median = -2, P = 0.008), and electromyography (Δ mean = 855, P = 0.005). A positive correlation between electromyography and clinical evaluation with eFACE was observed (r = 0.751, 95% confidence interval = 0.174-0.944, P = 0.019). Our results suggest that cross nerve grafts are associated with clinical and electromyographic improvement of the paralyzed face. Electromyography and eFACE scores validate the reliability of eFACE scale for measuring postoperative outcomes. We suggest postoperative electromyography as an objective measure of postoperative evaluation in patients with a delay in improvement at 6-9 months.

Anatomical Identification and Possibilities of Transfer of the Masseteric Nerve for Facial Reanimation

The masseteric nerve (MN) is often used as a donor nerve for facial reanimation. In addition to already established techniques, MN transfer is rapidly gaining importance, mainly due to the single-stage approach of the procedure and its reconstructive potential. This anatomical study and the associated questionnaire study aimed to evaluate the established methods for identification of the MN and its suitability for direct nerve transfer as well as to assess the importance of MN transfer in the daily clinical routine. Bilateral dissection of 25 fresh-frozen head specimens (n=50; 13 female, 12 male) was performed with accompanying measurement of the MN. In a questionnaire study conducted at established centres for facial surgery in German-speaking countries, clinical experience data of MN transfer was collected using the SurveyMonkey software. The data obtained was statistically analysed using Microsoft Excel and presented in numerical tables and boxplots. Using anatomical landmarks such as the zygomatic arch and the mandibular notch for orientation, the MN was found in 100% of cases. Its average length from the emerging point below the zygomatic arch towards its entry into the masseter muscle was measured to be 22 mm and was the length available for nerve transposition. Tension-free coaptation of the MN with the zygomatic branch was possible in 94% of cases. The questionnaire showed that the MN is considered an important donor nerve for motor nerve transfers and that MN transfer is now largely established as a standard procedure. In accordance with previously published studies, the MN was reliably found at the height of the mandibular notch and, in the vast majority of cases, was suitable for tension-free coaptation with the zygomatic branch. Differences to the existing literature, however, can be seen in the length of the nerve available for nerve transposition and the frequency of its division into several branches before entering the masseter muscle. In German-speaking countries, Cross-Face Nerve Grafting (CFNG) is still the preferred method for facial reanimation surgery. However, MN transfer is also well established by now, both as an alternative and a supplement to other techniques, possibly due to its low donor site morbidity and short time to regeneration.

A Novel Approach to Facial Reanimation and Restoration Following Radical Parotidectomies.

Background: Parotidectomies are indicated for a variety of reasons. Regardless of the indication for surgery, facial reanimation may be required because of facial nerve sacrifice or iatrogenic damage. In these cases, facial restoration performed concurrently with ablative surgery is considered the gold standard, and delayed reanimation is usually not attempted. Methods: A retrospective review of all patients who underwent parotidectomies from 2009 to 2022 in a single institution was performed. Indications, surgical techniques, and outcomes of an algorithmic template were applied to these cases using the Sunnybrook, Terzis scores, and Smile Index. A comparison was made between immediate vs. late repairs. Results: Of a total of 90 patients who underwent parotidectomy, 17 (15.3%) had a radical parotidectomy, and 73 (84.7%) had a total or superficial parotidectomy. Among those who underwent complete removal of the gland and nerve sacrifice, eight patients (47.1%) had facial restoration. There were four patients each in the immediate (n = 4) and late repair (n = 4) groups. Surgical techniques ranged from cable grafts to vascularized cross facial nerve grafts (sural communicating nerve flap as per the Koshima procedure) and vascularized nerve flaps (chimeric vastus lateralis and anterolateral thigh flaps, and superficial circumflex perforator flap with lateral femoral cutaneous nerve). Conclusions: The algorithm between one technique and another should take into consideration age, comorbidities, soft tissue defects, presence of facial nerve branches for reinnervation, and donor site morbidity. While immediate facial nerve repair is ideal, there is still benefit in performing a delayed repair in this algorithm.

Facial palsy reconstruction.

The facial nerve stimulates the muscles of facial expression and the parasympathetic nerves of the face. Consequently, facial nerve paralysis can lead to facial asymmetry, deformation, and functional impairment. Facial nerve palsy is most commonly idiopathic, as with Bell palsy, but it can also result from a tumor or trauma. In this article, we discuss traumatic facial nerve injury. To identify the cause of the injury, it is important to first determine its location. The location and extent of the damage inform the treatment method, with options including primary repair, nerve graft, cross-face nerve graft, nerve crossover, and muscle transfer. Intracranial proximal facial nerve injuries present a challenge to surgical approaches due to the complexity of the temporal bone. Surgical intervention in these cases requires a collaborative approach between neurosurgery and otolaryngology, and nerve repair or grafting is difficult. This article describes the treatment of peripheral facial nerve injury. Primary repair generally offers the best prognosis. If primary repair is not feasible within 6 months of injury, nerve grafting should be attempted, and if more than 12 months have elapsed, functional muscle transfer should be performed. If the affected nerve cannot be utilized at that time, the contralateral facial nerve, ipsilateral masseter nerve, or hypoglossal nerve can serve as the donor nerve. Other accompanying symptoms, such as lagophthalmos or midface ptosis, must also be considered for the successful treatment of facial nerve injury.

Demographic review of aesthetic surgery for patients with facial palsy.

This study analyzed the demographic characteristics of patients with facial palsy who were treated using either dynamic or static procedures. This study aimed to compare the frequency of procedure implementation and age distribution between the two groups. This study retrospectively analyzed the medical records of patients treated for facial palsy at a single institution from 2014 to 2022. Among cases included in our study, dynamic procedures involved cross-facial nerve graft and latissimus dorsi or gracilis muscle flap transfer. Static procedures included gold weight insertion, canthopexy, browlift, and thread lift/static slings. Among the 31 patients included in our study, eight (25.8%) incorporated dynamic techniques, and the average age of patients was 44.75 years (range, 24-68 years) with a male to female ratio of 1:4. The remaining 23 patients (74.2%) underwent a static procedure, of which the average age was 59.17 years (range, 23-81 years) which was statistically significantly higher than the average age of 44.75 of dynamic patients (p= 0.013). Regarding the timing of treatment after diagnosis, no patient underwent dynamic procedures more than 20 years after initial diagnosis. A greater diversity in the timing of treatment was observed in the static group. All patients who underwent dynamic procedures were treated using static procedures during the study period. Because aesthetics-based static techniques are typically quick outpatient procedures that can be performed under local anesthesia, our study shows that these are often preferred treatments for all age groups, especially for debilitated or older patients. Further research is required to investigate the long-term functional outcomes of these surgical techniques in a wider population of patients.

Reanimation of the Lower Lip with the Anterior Belly of Digastric Transfer: A Systematic Review.

Background: Dynamic reanimation of the lower lip is a challenging issue for patients, with depressor asymmetry commonly addressed with chemodenervation, selective neurectomy, or myectomy. Objective: To determine whether the anterior belly of digastric transfer is an effective method of lower-lip reanimation for patients with either isolated marginal mandibular branch weakness or inadequate depressor function after hemifacial reanimation, as measured by patient satisfaction and objective symmetry evaluation. Method: Systematic review of the literature was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Abstracts and full texts were reviewed. A Risk of Bias assessment was performed. Results: Nine studies with 164 patients were included. Anterior belly of digastric transfer was successfully performed in 162 patients. Most patients (52%) underwent one-staged reanimation innervated by the native nerve to the mylohyoid. A two-staged approach after placement of a cross face nerve graft was performed in 46%. Patient satisfaction was excellent (90.6%), with minimal complications including revision (4/162), infection (4/162), and lipofilling (8/162). Conclusion: In patients seeking a permanent outcome, use of an anterior belly of digastric transfer in either a one-stage or two-stage approach appears to be a safe and effective method to restore symmetry and dynamic function.

Novel Method of Dual-innervated Free Gracilis Muscle Transfer for Facial Reanimation: A Case Series.

Dynamic facial reanimation is the gold standard treatment for a paralyzed face. The use of the cross-face nerve graft (CFNG) in combination with the masseteric nerve to innervate the free gracilis muscle has been reported to provide both spontaneity and strong neural input. We report a case series of dual innervation, using a novel method where the branch to masseter is coapted to the side of the CFNG. Eight patients received free gracilis muscle transfer using the new dual innervation method between September 2014 and December 2017. The CFNG, which was performed nine months prior, was sutured in an end-to-end fashion to the obturator nerve. A nerve graft was coapted to the ipsilateral masseteric nerve and then sutured in an end-to-side fashion to the CFNG proximal to its coaptation to the obturator nerve. All patients recovered smile function with and without teeth clenching around the same time period. Smiles without teeth clenching appeared later in two of eight patients and earlier in one of eight patients, being noted at an average of 8.25 months of follow-up versus 7.6 months. The estimate of true attainment is limited by the spacing of follow-up dates. Average follow-up time was 36.07 months (range: 10-71.5). FACE-Gram software smile analysis with and without biting demonstrated similar excursion on average (7.64 mm versus 8.6 mm respectively, P = 0.93), both of which are significantly improved from preoperation. This novel method of a dual-innervated free gracilis muscle transfer offers a viable technique that achieves a symmetric, strong, and emotional smile.

Restoring the spontaneous smile through free functional muscle transfer. A systematic review and meta-analysis of the last twenty years’ experience

The recovery of the spontaneous smile has become a primary focus in facial reanimation surgery and its major determinant is the selected neurotizer. We aimed to compare the spontaneity outcomes of the most preferred neurotization methods in free functional muscle transfer for long-standing facial paralysis. The Embase, Ovid Medline, and PubMed databases were queried with 21 keywords. All clinical studies from the last 20 years reporting the postoperative spontaneity rate for specified neurotization strategies [cross-face nerve graft (CFNG), contralateral facial nerve (CLFN), motor nerve to the masseter (MNM), and dual innervation (DI)] were included. A meta-analysis of prevalence was performed using Freeman-Tukey double arcsine transformation, I2 statistic, and generic inverse variance with a random-effects model. Risk Of Bias In Non-randomized Studies of Interventions and Newcastle-Ottawa scale were used to assess bias and study quality. The literature search produced 2613 results and 473 unique citations for facial reanimation. Twenty-nine studies including 2046 patients were included in the systematic review. A meta-analysis of eligible data (1952 observations from 23 studies) showed statistically significant differences between the groups (CFNG: 0.94; 95% confidence interval [CI], 0.76-1.00, CLFN: 0.91; 95% CI, 0.49-1.00, MNM: 0.26; 95% CI, 0.05-0.54, DI: 0.98; 95% CI, 0.90-1.00, P<0.001). In pairwise comparisons, statistically significant differences were found between MNM and other neurotization strategies (P<0.001 in CFNG compared with MNM, P=0.013 for CLFN compared with MNM, P<0.001 for DI compared with MNM). DI- and CLFN-driven strategies achieved the most promising outcomes, whereas MNM showed the potential to elicit spontaneous smile at a lower extent. Our meta-analysis was limited primarily by incongruency between spontaneity assessment systems. Consensus on a standardized tool would enable more effective comparisons of the outcomes.

Comparison of Outcomes of Facial Reanimation Between the Use of Cross-facial Nerve Graft and the Masseteric Nerve as the Donor Nerve for Reinnervation of Gracilis Muscle Flap Transfer.

In patients with facial paralysis, the free functional gracilis muscle transfer is preferred for facial reanimation. The choice of an adequate motor nerve to innervate the transplanted gracilis muscle is one of the procedure's key components. We present a comparative study between cross-facial nerve graft (CFNG) and masseteric nerve as donor nerves for reinnervated gracilis flap transfer in patients with complete facial paralysis. Retrospective analysis was performed on all patients with complete facial paralysis who had a free functional gracilis muscle transfer for facial reanimation between January 2014 and December 2021. Only those who received gracilis transfer reinnervated by either CFNG or masseteric nerve were included in this study. The smile excursion and lip angle were measured for evaluating the outcomes postoperatively. The inclusion criteria were met by a total of 21 free functional gracilis muscle transfers, of which 11 were innervated by CFNG and 10 by the masseteric nerve. Both surgical procedures resulted in a highly considerable smile excursion of the reanimated side and postoperative improvement of static or dynamic lip angle. Masseteric nerve coaptation led to greater smile excursion and more significant improvement of dynamic lip angle than CFNG. For patients who have complete facial paralysis, face reanimation can be successfully accomplished by free gracilis transfer reinnervated by the CFNG or the masseteric nerve. In particular, the masseteric nerve is a reliable choice for dynamic smile reanimation.

Research trends and perspectives on immediate facial reanimation in radical parotidectomy (Review).

For patients diagnosed with advanced malignant parotid tumour, radical parotidectomy with facial nerve sacrifice is part of the treatment. Multiple surgical techniques have been developed to cure facial paralysis in order to restore the function and aesthetics of the face. Despite the large number of publications over time on facial nerve reanimation, a consensus on the timing of the procedure or the donor graft selection has remained to be established. Therefore, the aim of the present study was to conduct a bibliometric analysis to identify and analyse scientific publications on the reconstruction of the facial nerve of patients who underwent radical parotidectomy with facial nerve sacrifice. The analysis on the topic was conducted using the built-in tool of the Scopus database and VOSviewer software. The first 100 most cited articles were separately reviewed to address the aim of the study. No consensus was found regarding the recommended surgical techniques for facial nerve reanimation. The most used donor cranial nerves for transfer included the following: Masseteric branch of the V nerve, contralateral VII nerve with cross-face graft, the XI nerve and the XII nerve. The best timing of surgery is also controversial depending on pre-exiting pathology and degree of nerve degeneration. However, most of the clinical experience suggests facial nerve restoration immediately after the ablative procedure to reduce complications and improve patients' quality of life.

Evaluation of Long-Term Surgical and Patient-Reported Outcomes after Pediatric Facial Reanimation.

Outcomes of pediatric facial reanimation beyond 10 years are not known. This cross-sectional study evaluated long-term surgical and patient-reported outcomes of adults who underwent smile reconstruction as children with either a cross-face nerve graft (CFNG) or masseter nerve transfer at least 10 years previously. Commissure excursion was quantified with FACE-Gram software at 3 time points: preoperatively, early postoperatively within 2 years, and at long-term follow-up. Patient-reported outcomes were evaluated with validated questionnaires (Facial Clinimetric Evaluation Scale, FACE-Q 1.0) and thematic analysis of semistructured interviews. Results are reported as median (interquartile range [IQR]). A total of 42 patients were included (26 women and 16 men). Median long-term follow-up was 19.3 years (IQR, 8.8 years) for CFNG and 17.6 years (IQR, 5.8 years) for masseter nerve transfer. For both groups, commissure excursion increased significantly from preoperative to early postoperative time points and remained stable at long-term follow-up (P < 0.0001). Commissure excursion at long-term follow-up between the 2 groups was not significantly different (CFNG, 5.0 mm [IQR, 9.4 mm]; masseter nerve transfer, 8.4 mm [IQR, 4.1 mm]); P > 0.05). For patient-reported outcomes, median Facial Clinimetric Evaluation Scale score was 72 of 100, and 95% of respondents agreed with the statement "I am pleased with the result" on the FACE-Q 1.0. Overall quality of life was rated at 7 of 10 or greater by 97% of participants, and all participants would recommend the surgery to other children. Pediatric facial reanimation with CFNG or masseter nerve transfer reliably improves commissure excursion with longevity beyond 10 years. Adult patients report overall high satisfaction and social functioning.

Triple nerve transfers for the management of early unilateral facial palsy.

Early onset facial paralysis is usually managed with cross-face nerve grafts, however the low number of axons that reach the target muscle may result in weakness or failure. Multiple-source innervation, or 'supercharging', seeks to combine the advantages of different donor nerves while minimizing their weaknesses. We propose a combination of cross-face nerve grafts with local extra-facial nerve transfers to achieve earlier facial reanimation in our patients. A retrospective cohort including all patients with early unilateral facial palsy (<12 months evolution) who underwent triple nerve transfer between 2019 and 2021 was conducted. We performed single-stage procedure including zygomatic-to-zygomatic and buccal-to-buccal cross-face grafts, a nerve-to-masseter to bucozygomatic trunk transfer, and a mini-hypoglossal to marginal branch transfer. Results were evaluated using the clinician-graded facial function scale (eFACE). Fifteen patients were included (eight females, seven males), mean age at the time of surgery was 48.9 ± 13.3 years. Palsy was right-sided in eight cases. The mean time from palsy onset to surgery was 5.5 ± 2.8 months. Patients showed improvement in static (70.8 ± 21.9 vs. 84.15 ± 6.68, p = 0.002) and dynamic scores (20 ± 16.32 vs. 74.23 ± 7.46, p < 0.001), as well as periocular (57.33 ± 15.23 vs. 74 ± 7.18, p = 0.007), smile (54.73 ± 11.93 vs. 85.62 ± 3.86, p < 0.001), mid-face (46.33 ± 18.04 vs. 95 ± 7.21, p < 0.001) and lower face scores (67.4 ± 1.55 vs. 90.31 ± 7.54, p < 0.001). The triple nerve transfer technique using cross-face nerve grafts, the nerve-to-masseter, and the hypoglossal nerve, is an effective and reproducible technique to obtain middle and lower face reanimation in cases of early facial palsy.

Histomorphometry of the Sural Nerve for Use as a CFNG in Facial Reanimation Procedures.

Facial palsy (FP) is a debilitating nerve pathology. Cross Face Nerve Grafting (CFNG) describes a surgical technique that uses nerve grafts to reanimate the paralyzed face. The sural nerve has been shown to be a reliable nerve graft with little donor side morbidity. Therefore, we aimed to investigate the microanatomy of the sural nerve. Biopsies were obtained from 15 FP patients who underwent CFNG using sural nerve grafts. Histological cross-sections were fixated, stained with PPD, and digitized. Histomorphometry and a validated software-based axon quantification were conducted. The median age of the operated patients was 37 years (5-62 years). There was a significant difference in axonal capacity decrease towards the periphery when comparing proximal vs. distal biopsies (p = 0.047), while the side of nerve harvest showed no significant differences in nerve caliber (proximal p = 0.253, distal p = 0.506) and axonal capacity for proximal and distal biopsies (proximal p = 0.414, distal p = 0.922). Age did not correlate with axonal capacity (proximal: R = -0.201, p = 0.603; distal: R = 0.317, p = 0.292). These novel insights into the microanatomy of the sural nerve may help refine CFNG techniques and individualize FP patient treatment plans, ultimately improving overall patient outcomes.

Functional Outcome of Dual Reinnervation with Cross-Facial Nerve Graft and Masseteric Nerve Transfer for Facial Paralysis.

The combination of cross-facial nerve graft (CFNG) and masseteric nerve transfer (MNT) for reinnervation of facial paralysis may provide advantages of both neural sources. However, quantitative functional outcome reports with a larger number of patients are lacking in the literature. Here, the authors describe their 8-year experience with this surgical technique. Twenty patients who presented with complete facial paralysis (duration, <12 months) received dual reinnervation with CFNG and MNT. The functional outcome of the procedure was evaluated with the physician-graded outcome metric eFACE scale. The objective artificial intelligence-driven software Emotrics and FaceReader were used for oral commissure measurements and emotional expression assessment, respectively. The mean follow-up was 31.75 ± 23.32 months. In the eFACE score, the nasolabial fold depth and oral commissure at rest improved significantly ( P < 0.05) toward a more balanced state after surgery. Postoperatively, there was a significant decrease in oral commissure asymmetry while smiling (from 19.22 ± 6.1 mm to 12.19 ± 7.52 mm). For emotional expression, the median intensity score of happiness, as measured by the FaceReader software, increased significantly while smiling (0.28; interquartile range, 0.13 to 0.64). In five patients (25%), a secondary static midface suspension with fascia lata strip had to be performed because of unsatisfactory resting symmetry. Older patients and patients with greater preoperative resting asymmetry were more likely to receive static midface suspension. The authors' results suggest that the combination of MNT and CFNG for reinnervation of facial paralysis provides good voluntary motion and may lessen the use of static midface suspension in the majority of patients. Therapeutic, IV.

Sural communicating nerve for application as a vascularized nerve graft: A microneurovascular anatomic study in cadavers.

Sural nerve harvest causes paraesthesia to the lateral heel of the foot, which can debilitate those with already compromised proprioception. To circumvent this, we investigated an alternative donor nerve, branch of the lateral sural nerve complex called the sural communicating nerve (SCoNe), for its harvest and use as a vascularized nerve graft, in cadaver. The SCoNe was visualized by dissection in 15 legs from 8 human cadavers and the relationship of the SCoNe to the overall sural nerve complex was documented. The surface markings, dimensions, and the micro-neurovascular anatomy in the super-microsurgery range (up to 0.30 mm) of the SCoNe was recorded and analyzed. SCoNe graft surface marking was confined within a triangle drawn between the fibular head laterally, the popliteal vertical midline medially and the tip of the lateral malleolus inferiorly. The proximal end of the SCoNe was situated at a mean intersection distance of 5 cm from both the fibular head and popliteal midline respectively. The mean length of the SCoNe was 226 ± 43 mm with a mean proximal diameter of 0.82 mm and mean distal diameter of 0.93 mm. In 53% of the cadavers, an arterial input was present in the proximal third of the SCoNe and veins were predominantly (87%) present in the distal third. In 46% and 20% of the 15 legs respectively, there was a nutrient artery and vein perfusing the SCoNe in its central segment. The external mean diameter of this artery was 0.60 ± 0.30 mm, while the vein was slightly larger with a mean diameter of 0.90 ± 0.50 mm. SCoNe graft may preserve lateral heel sensation, compared to sural nerve harvest, pending clinical studies. It may have wide applications as a vascularized nerve graft, including being ideal as a vascularized cross-facial nerve graft because its nerve diameter is similar to the distal facial nerve branches. The accompanying artery is a good anastomotic match to the superior labial artery.

Letter to "The Split Hypoglossal Nerve and Cross-Face Nerve Graft for Dual Innervation of the Functional Muscle Transfer in Facial Reanimation".

Gurbuz, Canberk MD*; Dursun, Buket MD†; Alagöz, Murat Şahin MD, PHD* Author Information

181. Novel Method Of Double Innervated Free Gracilis Muscle Functional Transfer For Facial Reanimation

PURPOSE: Dynamic facial reanimation is the gold standard treatment for a paralyzed face. The use of the cross-face nerve graft (CFNG) in combination with the masseteric nerve to innervate the free gracilis muscle has been reported, with the goal of providing both spontaneity from the CFNG and strong neural input from the masseteric nerve. We report a series of patients who underwent a novel modification to the existing nerve coaptation configurations. METHODS: Eight patients (Image 1 below) received free gracilis muscle transfer using the new double innervation method between September 2014 and December 2017. The CFNG, which was performed nine months prior, was sutured in an end-to-end fashion to the obturator nerve. A nerve graft was coapted to the ipsilateral masseteric nerve and then sutured in an end-to-side fashion to the CFNG proximal to the end-to-end obturator coaptation (Image 2 below). RESULT: All patients recovered smile function with teeth clenching (average 7.5 months, range 3-12). Seven of eight patients recovered a strong spontaneous smile by an average of 8.9 months (range 7-12), with one patient having weak spontaneous function after 12 months of follow-up. Average follow-up time was 31.52 months. All patients achieved improvements in their smile excursion based on the FACE-Gram software. Smile with or without biting achieved similar excursion on average (7.91mm vs.8.04mm, p=0.93). CONCLUSION: Our novel method of a double-innervated free gracilis muscle transfer represents a viable technique that does not risk denervation of the gracilis muscle and provides a symmetric, spontaneous, emotional smile.