Recovery of facial expressions using functional electrical stimulation after full-face transplantation

Delta waves as a sign of cortical plasticity after full-face transplantation

This study focused on detecting the reflections of healing and change in cortex activation in full-face transplantation and lesions patients on EEG activity. Face transplant patients have facial lesions before transplantation and, to identify pre-face transplant patients' brain activity in the absence of pre-transplant recordings, we used data obtained from pre-transplant facial lesion patients. Ten healthy, four facial lesion and three full-face transplant patients participated in this study. EEG data recorded for four different sensory stimuli (brush from the right face, right hand, left face, and left-hand regions) were analyzed using wavelet packet transform method. EEG waves were analyzed for standard bands. Our findings indicate significant change in the 2-4 Hz frequency range which may be a result of ongoing or previous cortical reorganization for face lesion and transplant patients. Alterations of the delta wave seen in patients with facial lesion and face transplant can also be explained by the intense central plasticity. Our findings show that the delta band differences might be used as a marker in the evaluation of post-transplant cortical plasticity in the future.

Acute Rejection Rates in Vascularized Composite Allografts: A Systematic Review of Case Reports

INTRODUCTION

Vascularized Composite Allografts (VCA) are usually performed in a full major histocompatibility complex mismatch setting, with a risk of acute rejection depending on factors such as the type of immunosuppression therapy and the quality of graft preservation. In this systematic review, we present the different immunosuppression protocols used in VCA and point out relationships between acute rejection rates and possible factors that might influence it.

METHODS

This systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We systematically searched Medline (PubMed), Embase, and The Cochrane Library between November 2022 and February 2023, using following Mesh Terms: Transplant, Transplantation, Hand, Face, Uterus, Penis, Abdominal Wall, Larynx, and Composite Tissue Allografts. All VCA case reports and reviews describing multiple case reports were included.

RESULTS

We discovered 211 VCA cases reported. The preferred treatment was a combination of antithymocyte globulins, mycophenolate mofetil (MMF), tacrolimus, and steroids; and a combination of MMF, tacrolimus, and steroids for induction and maintenance treatment, respectively. Burn patients showed a higher acute rejection rate (P = 0.073) and were administered higher MMF doses (P = 0.020).

CONCLUSIONS

In contrast to previous statements, the field of VCA is not rapidly evolving, as it has encountered challenges in addressing immune-related concerns. This is highlighted by the absence of a standardized immunosuppression regimen. Consequently, more substantial data are required to draw more conclusive results regarding the immunogenicity of VCAs and the potential superiority of one immunosuppressive treatment over another. Future efforts should be made to report the VCA surgeries comprehensively, and muti-institutional long-term prospective follow-up studies should be performed to compare the number of acute rejections with influencing factors.

Long-term outcomes and future challenges in face transplantation

Face transplant (FT) has emerged as a groundbreaking option for patients with severe facial deformities, resulting from congenital disorders, trauma, or tumor ablation. Although reconstructive surgery has made significant strides, the challenges of restoring both form and function remain, particularly in centrally located defects. This review explored the long-term outcomes of FT, addressing its challenges and potential pitfalls. A systematic review following the PRISMA guidelines was conducted, encompassing articles published in English from November 2005 to January 2023, which were searched across PubMed, MEDLINE, and EMBASE databases. Keywords included "face transplant," "face transplant outcomes," and "face transplant long-term." Data on surgical teams, patient demographics, transplant specifics, rejection episodes, additional surgeries, and patient-reported outcomes were extracted and analyzed. In total, 34 articles met the inclusion criteria. Over the 2 decades, 48 FT procedures were performed, with 23 patients followed for at least 3 years. Predominantly, patients were men (80%), averaging 31 years in age. Ballistic trauma (44.6%) and burns (25.5%) were common causes of injury. Chronic rejection emerged as a significant concern, leading to graft loss and necessitating retransplantation in 2 patients. Additional surgical procedures were often required. FT offers a remarkable solution for individuals with extensive facial disfigurement. Successful outcomes depend on factors, such as patient selection, multidisciplinary collaboration, psychiatric evaluation, and post-operative care. Nevertheless, challenges persist, including the need for lifelong immunosuppression and risk of chronic rejection. Although FT has transformed lives, continued success in this evolving field hinges on the ongoing research and vigilant patient management.

Application of facial neuromuscular electrical stimulation (fNMES) in psychophysiological research: Practical recommendations based on a systematic review of the literature

Facial neuromuscular electrical stimulation (fNMES), which allows for the non-invasive and physiologically sound activation of facial muscles, has great potential for investigating fundamental questions in psychology and neuroscience, such as the role of proprioceptive facial feedback in emotion induction and emotion recognition, and may serve for clinical applications, such as alleviating symptoms of depression. However, despite illustrious origins in the 19th-century work of Duchenne de Boulogne, the practical application of fNMES remains largely unknown to today's researchers in psychology. In addition, published studies vary dramatically in the stimulation parameters used, such as stimulation frequency, amplitude, duration, and electrode size, and in the way they reported them. Because fNMES parameters impact the comfort and safety of volunteers, as well as its physiological (and psychological) effects, it is of paramount importance to establish recommendations of good practice and to ensure studies can be better compared and integrated. Here, we provide an introduction to fNMES, systematically review the existing literature focusing on the stimulation parameters used, and offer recommendations on how to safely and reliably deliver fNMES and on how to report the fNMES parameters to allow better cross-study comparison. In addition, we provide a free webpage, to easily visualise fNMES parameters and verify their safety based on current density. As an example of a potential application, we focus on the use of fNMES for the investigation of the facial feedback hypothesis.

Modulation of the Crosstalk between Schwann Cells and Macrophages for Nerve Regeneration: A Therapeutic Strategy Based on a Multifunctional Tetrahedral Framework Nucleic Acids System

Peripheral nerve injury (PNI) is currently recognized as one of the most significant public health issues and affects the general well-being of millions of individuals worldwide. Despite advances in nerve tissue engineering, nerve repair still cannot guarantee complete functional recovery. In the present study, an innovative approach is adopted to establish a multifunctional tetrahedral framework nucleic acids (tFNAs) system, denoted as MiDs, which can integrate the powerful programmability, permeability, and structural stability of tFNAs, with the nerve regeneration potential of microRNA-22 to enhance the communication between Schwann cells (SCs) and macrophages for more effective functional rehabilitation of peripheral nerves. Relevant results demonstrate that MiDs can amplify the ability of SCs to recruit macrophages and facilitate their polarization into the pro-healing M2 phenotype to reconstruct the post-injury microenvironment. Furthermore, MiDs can initiate the adaptive intracellular reprogramming of SCs within a short period to further promote axon regeneration and remyelination. MiDs represent a new possibility for enhancing nerve repair and may have critical clinical applications in the future.

Whole-Body Adaptive Functional Electrical Stimulation Kinesitherapy Can Promote the Restoring of Physiological Muscle Synergies for Neurological Patients

Background: Neurological diseases and traumas are major factors that may reduce motor functionality. Functional electrical stimulation is a technique that helps regain motor function, assisting patients in daily life activities and in rehabilitation practices. In this study, we evaluated the efficacy of a treatment based on whole-body Adaptive Functional Electrical Stimulation Kinesitherapy (AFESK™) with the use of muscle synergies, a well-established method for evaluation of motor coordination. The evaluation is performed on retrospectively gathered data of neurological patients executing whole-body movements before and after AFESK-based treatments. Methods: Twenty-four chronic neurologic patients and 9 healthy subjects were recruited in this study. The patient group was further subdivided in 3 subgroups: hemiplegic, tetraplegic and paraplegic. All patients underwent two acquisition sessions: before treatment and after a FES based rehabilitation treatment at the VIKTOR Physio Lab. Patients followed whole-body exercise protocols tailored to their needs. The control group of healthy subjects performed all movements in a single session and provided reference data for evaluating patients’ performance. sEMG was recorded on relevant muscles and muscle synergies were extracted for each patient’s EMG data and then compared to the ones extracted from the healthy volunteers. To evaluate the effect of the treatment, the motricity index was measured and patients’ extracted synergies were compared to the control group before and after treatment. Results: After the treatment, patients’ motricity index increased for many of the screened body segments. Muscle synergies were more similar to those of healthy people. Globally, the normalized synergy similarity in respect to the control group was 0.50 before the treatment and 0.60 after (p < 0.001), with improvements for each subgroup of patients. Conclusions: AFESK treatment induced favorable changes in muscle activation patterns in chronic neurologic patients, partially restoring muscular patterns similar to healthy people. The evaluation of the synergic relationships of muscle activity when performing test exercises allows to assess the results of rehabilitation measures in patients with impaired locomotor functions.

Long-term Outcomes After Facial Allotransplantation: Systematic Review of the Literature

BACKGROUND

Facial vascularized composite allotransplantation (fVCA) represents a reconstructive approach that enables superior improvements in functional and esthetic restoration compared with conventional craniomaxillofacial reconstruction. Outcome reports of fVCA are usually limited to short-term follow-up or single-center experiences. We merge scientific literature on reported long-term outcome data to better define the risks and benefits of fVCA.

METHODS

We conducted a systematic review of PubMed/MEDLINE databases in accordance with PRISMA guidelines. English full-text articles providing data on at least 1 unique fVCA patient, with ≥3 years follow-up, were included.

RESULTS

The search yielded 1812 articles, of which 28 were ultimately included. We retrieved data on 23 fVCA patients with mean follow-up of 5.3 years. More than half of the patients showed improved quality of life, eating, speech, and motor and sensory function following fVCA. On average, the patients had 1 acute cell-mediated rejection and infectious episode per year. The incidence rates of acute rejection and infectious complications were high within first-year posttransplant but declined thereafter. Sixty-five percent of the patients developed at least 1 neoplastic or metabolic complication after transplantation. Chronic vascular rejection was confirmed in 2 patients, leading to allograft loss after 8 and 9 years. Two patient deaths occurred 3.5 and 10.5 years after transplant due to suicide and lung cancer, respectively.

CONCLUSIONS

Allograft functionality and improvements in quality of life suggest a positive risk-benefit ratio for fVCA. Recurrent acute rejection episodes, chronic rejection, immunosuppression-related complications, and heterogeneity in outcome reporting present ongoing challenges in this field.

Complementary Phenomena: Phantom Hand and Phantom Face

After tissue or limb loss, the development of sensation and perception of the lost or deafferent tissue is defined as a phantom phenomenon. We investigated the presence of phantom phenomena in individuals who underwent a full face transplant as well as those who had a hand transplant. Specifically, we investigated sensory perception of the face on the fingers and sensory perception of the fingers on the face in three full face and four hand transplant patients. In all seven individuals, we used a brush to separately stimulate the right and left sides of the face or the palmar and dorsal faces of the hand. We then asked the individuals if they felt a sensation of touch on any other part of their body and, if so, to describe their perceptions. Changes in the regions of the primary sensory cortex representing the hand and face were defined using fMRI obtained via tactile sensory stimulation of the clinical examination areas. Two of the full face transplant patients reported sensory perceptions such as a prominent sensation of touch on their faces during sensory stimulation of their fingers. Three of the hand transplant patients reported sensory perceptions, which we referred to as finger patches, during sensory stimulation of the face area. In fMRI, overlaps were observed in the cortical hand and face representation areas. We consider the phantom hand and phantom face phenomena we observed to be complementary due to the neighborhood of the representations of the hand and face in the somatosensory cortex.

The 2020 Facial Transplantation Update: A 15-Year Compendium

Over the past 15 years, landmark achievements have established facial transplantation (FT) as a feasible reconstructive option for otherwise irreparable craniofacial defects. However, as the field matures and long-term outcomes begin to emerge, FT teams around the world are now facing new challenges. Data for this review were identified by searches of the PubMed/MEDLINE database from inception through August 2020. All English-language articles pertaining to FT were included. Significant advances in candidate selection, technology, operative technique, posttransplant care, and immunosuppressive management have contributed to the tremendous expansion of the field, culminating in the execution in the past 3 years of 2 facial re-transplantations, and most recently the world’s first successful combined face and double hand transplant in August 2020. Despite these achievements, the allograft donor pool remains limited, with long wait times, requiring surgical experimentation with cross-sex FT. Immunosuppressive management has improved, but significant adverse events continue to be reported. Most recently, the COVID-19 pandemic has placed an unprecedented strain on the healthcare system, with various implications for the practice of reconstructive transplantation. In this article, we provide the most comprehensive and up-to-date FT review, highlighting fundamental lessons learned and recent advancements, while looking toward the challenges ahead. Over the past 15 years, extensive multidisciplinary efforts have been instrumental to the establishment of FT as a feasible reconstructive option. As novel challenges are beginning to emerge, continued collaborative and multispecialty research efforts are needed to further this field.

Recognizing Emotional Expression as an Outcome Measure After Face Transplant

IMPORTANCE

Limited quantitative data exist on the restoration of nonverbal communication via facial emotional expression after face transplant. Objective and noninvasive methods for measuring outcomes and tracking rehabilitation after face transplant are lacking.

OBJECTIVE

To measure emotional expression as an indicator of functional outcomes and rehabilitation after face transplant via objective, noninvasive, and nonobtrusive software-based video analysis.

DESIGN, SETTING, AND PARTICIPANTS

This single-center case-control study analyzed videos with commercially available video analysis software capable of detecting emotional expression. The study participants were 6 patients who underwent face transplant at Brigham and Women's Hospital between April 2009 and March 2014. They were matched by age, race/ethnicity, culture, and sex to 6 healthy controls with no prior facial surgical procedures. Participants were asked to perform either emotional expressions (direct evaluation) or standardized facial movements (indirect evaluation). Videos were obtained in a clinical setting, except for direct evaluation videos of 3 patients that were recorded at the patients' residences. Data analysis was performed from June 2018 to November 2018.

MAIN OUTCOMES AND MEASURES

The possibility of detecting the emotional expressions of happiness, sadness, anger, fear, surprise, and disgust was evaluated using intensity score values between 0 and 1, representing expressions that are absent or fully present, respectively.

RESULTS

Six patients underwent face transplant (4 men; mean [SD] age, 42 [14] years). Four underwent full face transplants, and 2 underwent partial face transplants of the middle and lower two-thirds of the face. In healthy controls, happiness was the only emotion reliably recognized in both indirect (mean [SD] intensity score, 0.92 [0.05]) and direct (mean [SD] intensity score, 0.91 [0.04]) evaluation. Indirect evaluation showed that expression of happiness significantly improved 1 year after transplant (0.04 point per year; 95% CI, 0.02 to 0.06 point per year; P = .002). Expression of happiness was restored to a mean of 43% (range, 14% to 75%) of that of healthy controls after face transplant. The expression of sadness showed a significant change only during the first year after transplant (-0.53 point per year; 95% CI, -0.82 to -0.24 point per year; P = .005). All other emotions were detectable with no significant change after transplant. Nearly all emotions were detectable in long-term direct evaluation of 3 patients, with expression of happiness restored to a mean of 26% (range, 5% to 59%) of that of healthy controls.

CONCLUSIONS AND RELEVANCE

Partial restoration of facial emotional expression is possible after face transplant. Video analysis software may provide useful clinical information and aid rehabilitation after face transplant.