Alice Frigerio

Masseteric–facial nerve anastomosis for early facial reanimation

OBJECTIVE Early repair of facial nerve paralysis when cortical neural input cannot be provided by the facial nerve nucleus, is generally accomplished anastomozing the extracranial stump of the facial nerve to a motor donor nerve. That is generally the hypoglossus, which carries a variable degree of morbidity. The present work aims to demonstrate the effectiveness of the masseteric nerve as donor for early facial reanimation, with the advantage that harvesting is associated with negligible morbidity. METHODS Between October 2007 and August 2009, 7 patients (2 males, 5 women) with unilateral facial paralysis underwent a masseter-facial nerves anastomosis with an interpositional nerve graft of the great auricular nerve. The interval between the onset of paralysis and surgery ranged from 8 to 48 months (mean 19.2 months). All patients included in the study had signs of facial mimetic muscle fibrillations on electromyography. The degree of preoperative facial nerve dysfunction was grade VI following the House-Brackmann scale for all patients. RESULTS At the time of the study, all the patients with a minimum follow-up time of 12 months after the onset of mimetic function had recovered facial animation. Facial muscles showed signs of recovery within 2-9 months, mean 4.8 months, with the restoration of facial symmetry at rest. Facial movements appeared while the patients activated their chewing musculature. Morbidity related to this intervention is only the loss of sensitivity of earlobe and preauricular region. CONCLUSION The present technique seems to be a valid alternative to classical hypoglossal-facial nerve anastomosis because of similar facial nerve recovery and lower morbidity.

Double innervation in free-flap surgery for long-standing facial paralysis

OBJECTIVE One-stage free-flap facial reanimation may be accomplished by using a gracilis transfer innervated by the masseteric nerve, but this technique does not restore the patients ability to smile spontaneously. By contrast, the transfer of the latissimus dorsi innervated by the contralateral facial nerve provides the correct nerve stimulus but is limited by variation in the quantity of contraction. The authors propose a new one-stage facial reanimation technique using dual innervation; a gracilis muscle flap is innervated by the masseteric nerve, and supplementary nerve input is provided by a cross-face sural nerve graft anastomosed to the contralateral facial nerve branch. METHODS Between October 2009 and March 2010, four patients affected by long-standing unilateral facial paralysis received gracilis muscle transfers innervated by both the masseteric nerve and the contralateral facial nerve. RESULTS All patients recovered voluntary and spontaneous smiling abilities. The recovery time to voluntary flap contraction was 3.8 months, and spontaneous flap contraction was achieved within 7.2 months after surgery. According to Terzis and Noahs five-stage classification of reanimation outcomes, two patients had excellent outcomes and two had good outcomes. CONCLUSIONS In this preliminary study, the devised double-innervation technique allows to achieve a good grade of flap contraction as well as emotional smiling ability. A wider number of operated patients are needed to confirm those initial findings.

Single-stage facial reanimation in the surgical treatment of unilateral established facial paralysis.

Background: Surgical treatment of unilateral long-standing facial paralysis requires transposition of new musculature to restore the function of the atrophied mimetic musculature. Facial reanimation with free neuromuscular flaps is actually the accepted standard treatment. Two-stage procedures have been used for years, with a total flap recovery time of 18 to 24 months. In 1998, Harii proposed single-stage facial reanimation using the latissimus dorsi flap, showing a faster recovery compared with two-stage procedures. The present study evaluated the results of the authors’ center applying the single-stage facial reanimation. Methods: From April of 1999 to April of 2006, 33 patients with unilateral established facial paralysis underwent single-stage facial reanimation via latissimus dorsi free flap transplantation. Time from the onset of paralysis ranged from 20 months to 64 years (mean, 11.6 years). Patients were followed postoperatively for at least 24 months. Results were studied and compared using Terzis and Noah’s 1997 classification. Results: Among the 33 patients included in the study, there was an average reinnervation time of 8.9 months. According to Terzis and Noah’s classification system, 12 patients (36.3 percent) were considered grade V, 12 (36.3 percent) were grade IV, four (12.2 percent) were grade III, two (6.1 percent) were grade II, and three (9.1 percent) were grade I. Conclusions: Single-stage facial reanimation with a latissimus dorsi flap achieved morphofunctional results similar to those obtained with the classic two-stage technique. In addition, the authors were able to reduce the morbidity associated with treatment and the time required for recovery.

Fibrous dysplasia of the orbital region: Current clinical perspectives in ophthalmology and cranio-maxillofacial surgery

Purpose: To describe the multidisciplinary diagnosis and treatment of patients with orbital fibrous dysplasia, a slowly progressive disease that may lead to asymmetry, disfigurement, and functional ocular problems. Methods: Ten patients with orbital fibrous dysplasia underwent bifrontal craniotomy through a coronal flap, with the removal of the supraorbital arch and dysplastic process involving the anterior and middle base of the skull. Four patients underwent superior orbital fissure and optic nerve canal decompression. Reconstruction was performed by using an autologous bone graft for both the adults and children, in whom a rib graft was preferred. The mean follow-up was 53.2 ± 18.3 months (range, 14 to 94 months). The patients’ preoperative status and postoperative status were compared. Results: The immediate and long-term morphologic and aesthetic results were good in all cases. All of the patients complained of some degree of diplopia during the immediate postoperative period, but the problem spontaneously resolved within 1 to 6 months in all but one case. No postoperative reduction in visual function was observed in the patients who underwent optic nerve decompression. The only reported complication was the irregular reabsorption of regrafted dysplastic bone in one patient. Conclusions: A multidisciplinary approach to orbital fibrous dysplasia is fundamental for treatment planning and execution.

Facial movement before and after masseteric-facial nerves anastomosis: A three-dimensional optoelectronic pilot study ☆

To quantify the effects of facial palsy reanimation, 14 patients aged 17-66 years were analysed. All patients had unilateral facial paralysis, and were candidates for surgical masseteric to facial nerve anastomosis. Two patient groups were measured: seven patients were waiting for surgery, the other seven patients had already been submitted to surgery, and had regained facial mimicry. Each patient performed three facial animations: brow raise; free smile; lip purse. These were recorded using an optoelectronic motion analyser. The three-dimensional coordinates of facial landmarks were obtained, their movements were computed, and asymmetry indices calculated (differential movements between the two hemi-faces: healthy and paretic/rehabilitated). Before surgery, mobility was larger in the healthy than in the paretic side; after surgery, the differences were reduced (brow raise and lip purse), or even reversed (smile). Before surgery, lip purse was performed with significant labial asymmetry (p=0.042; larger healthy side movement). After surgery, asymmetry indices reduced. Total labial asymmetry during smiling was significantly different from 0 before surgery (p=0.018, larger healthy side movement). After surgery, all asymmetry indices became non-significant. Before surgery the lateral displacements of all labial landmarks were towards the healthy side, while they normalized after surgery.

Recovery of emotional smiling function in free-flap facial reanimation.

PURPOSE Long-standing unilateral facial palsy is treated primarily with free-flap surgery using the masseteric or contralateral facial nerve as a motor source. The use of a gracilis muscle flap innervated by the masseteric nerve restores the smiling function, without obtaining spontaneity. Because emotional smiling is an important factor in facial reanimation, the facial nerve must serve as the motor source to achieve this fundamental target. MATERIALS AND METHODS From October 1998 to October 2009, 50 patients affected by long-standing unilateral facial paralysis underwent single-stage free-flap reanimation procedures to recover smiling function. A latissimus dorsi flap innervated by the contralateral facial nerve was transplanted in 40 patients, and a gracilis muscle flap innervated by the masseteric nerve in 10 patients. All patients underwent a clinical examination that analyzed voluntary and spontaneous smiling. RESULTS All patients who received a latissimus dorsi flap innervated by the contralateral facial nerve and recovered muscle function (92.5%) showed voluntary and spontaneous smiling abilities. All patients who received a gracilis free flap innervated by the masseteric nerve recovered function, but only 1 (10%) showed occasional spontaneous flap activation. During those rare activations, much less movement was visible on the operated side than when the patient was asked to smile voluntarily. CONCLUSIONS The masseteric nerve is a powerful motor source that guarantees free voluntary gracilis muscle activation; however, it does not guarantee any spontaneous smiling. Single-stage procedures that use a latissimus dorsi flap innervated by the contralateral facial nerve have a lower success rate and obtain less movement; however, spontaneous smiling is always observed.

A Closed-Loop Stimulation System Supplemented with Motoneurone Dynamic Sensitivity Replicates Natural Eye Blinks

Objective. The authors are designing an implantable device that will electrically stimulate a paretic eyelid when electrodes implanted into the contralateral healthy orbicularis oculi muscle detect a spontaneous blink activity. As a novelty, the stimulation pattern includes the dynamic sensitivity of motor units, thus obtaining complete eyelid closure, tailored on the kinematics of the natural eye blink. Study Design. A preliminary study was performed on 10 healthy subjects, to observe, first, the kinematics of their natural eye blink and, second, the eye blink stimulated by a dynamic vs nondynamic pattern. Setting. A microaccelerometer taped onto the left upper eyelid detected its kinematics. A dedicated LabView software built up and triggered the stimulation pattern. A webcam recorded the behavioral effect. Subjects and Methods. The kinematics of spontaneous eye blinks was detected. Then, an epicutaneous stimulation of the facial nerve branch for the left orbicularis oculi muscle was performed on the same subjects. Muscle recruitment curves were studied, and acceleration of the bionic blink was measured and compared with the natural one. Results. Kinematics of the natural eyelid is highly variable within subjects. The stimulation pattern frequency was set case by case in order to obtain the desired eyelid acceleration of the contralateral eye. A custom-fit dynamic stimulation leads to a symmetrical natural-like eye blink. Conclusions. By adding the dynamic pulse, the authors were able to tailor a bionic eye blink, which was hardly distinguishable from the subject’s natural one.

Electrical Stimulation of Eye Blink in Individuals with Acute Facial Palsy: Progress toward a Bionic Blink.

Background: Elicitation of eye closure and other movements via electrical stimulation may provide effective treatment for facial paralysis. The authors performed a human feasibility study to determine whether transcutaneous neural stimulation can elicit a blink in individuals with acute facial palsy and to obtain feedback from participants regarding the tolerability of surface electrical stimulation for daily blink restoration. Methods: Forty individuals with acute unilateral facial paralysis, HB grades 4 through 6, were prospectively studied between 6 and 60 days of onset. Unilateral stimulation of zygomatic facial nerve branches to elicit eye blink was achieved with brief bipolar, charge-balanced pulse trains, delivered transcutaneously by adhesive electrode placement; results were recorded on a high-speed video camera. The relationship between stimulation parameters and cutaneous sensation was analyzed using the Wong-Baker Faces Pain Rating Scale. Results: Complete eye closure was achieved in 55 percent of participants using stimulation parameters reported as tolerable. In those individuals, initial eye twitch was observed at an average current of 4.6 mA (±1.7; average pulse width of 0.7 ms, 100 to 150 Hz), with complete closure requiring a mean of 7.2 mA (±2.6). Conclusions: Transcutaneous facial nerve stimulation may artificially elicit eye blink in a majority of patients with acute facial paralysis. Although individuals varied widely in their reported degrees of discomfort from blink-eliciting stimulation, most of them indicated that such stimulation would be tolerable if it could restore eye closure. These patients would therefore benefit from a biomimetic device to facilitate eye closure until the recovery process is complete. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Determining the threshold for asymmetry detection in facial expressions

To quantify the threshold for human perception of asymmetry for eyebrow elevation, eye closure, and smile, and to ascertain whether asymmetry detection thresholds and perceived severity of asymmetry differ in distinct facial zones.

Genetic Variants Associated with Port-Wine Stains

Background Port-wine stains (PWS) are capillary malformations, typically located in the dermis of the head and neck, affecting 0.3% of the population. Current theories suggest that port-wine stains are caused by somatic mutations that disrupt vascular development. Objectives Understanding PWS genetic determinants could provide insight into new treatments. Methods Our study used a custom next generation sequencing (NGS) panel and digital polymerase chain reaction to investigate genetic variants in 12 individuals with isolated port-wine stains. Importantly, affected and healthy skin tissue from the same individual were compared. A subtractive correction method was developed to eliminate background noise from NGS data. This allowed the detection of a very low level of mosaicism. Results A novel somatic variant GNAQ, c.547C>G, p.Arg183Gly was found in one case with 4% allele frequency. The previously reported GNAQ c.548G>A, p.Arg183Gln was confirmed in 9 of 12 cases with an allele frequency ranging from 1.73 to 7.42%. Digital polymerase chain reaction confirmed novel variants detected by next generation sequencing. Two novel somatic variants were also found in RASA1, although neither was predicted to be deleterious. Conclusions This is the second largest study on isolated, non-syndromic PWS. Our data suggest that GNAQ is the main genetic determinant in this condition. Moreover, isolated port-wine stains are distinct from capillary malformations seen in RASA1 disorders, which will be helpful in clinical evaluation.