Surgery for patients with facial palsy in Germany: a diagnosis-related-groups-based nationwide analysis, 2005-2019.

PURPOSE: Chronic flaccid paralysis of the facial nerve leads to permanent dysfunction of eye closure, problems with drinking and eating, and lack of emotional expression. Modern facial surgery can help those affected. An analysis of the development of facial surgery in Germany over time is presented. METHODS: Nation-wide population-baes diagnosis-related case group (DRG) data of virtually all inpatients who underwent facial surgery for facial palsy between 2005 and 2019 were included. Binomial regression models for changes in surgery rates over time were calculated in relation to gender and treating specialty. RESULTS: Between 2005 and 2019, there were 28,622 inpatient stays for facial surgery. Most surgeries were provided by otolaryngology (39%) and ophthalmology or dentistry, oral and maxillofacial surgery (20% each). The mean treatment rate was 2.33 ± 0.53 surgeries per 100,000 person-years. The surgery rate was highest for nerve reconstruction surgery (0.46 ± 0.15) and static sling surgery (0.44 ± 0.0.16). The greatest increase was seen in men for nerve surgery (3.9-fold; relative risk [RR] = 3.68; confidence interval [CI] = 3.18-4.26) and sling surgery (5.0-fold; RR = 4.25; CI = 3.38-5.33). CONCLUSIONS: While nerve and sling surgery increased significantly over time, this was less true or not true at all for surgical techniques. Surgical rates and their change over time were greater in men, without explanation from the data.

The diagnostic utility of inspiratory-expiratory radiography for the assessment of phrenic nerve palsy associated with brachial plexus injury.

BACKGROUND: The phrenic nerve is commonly injured with trauma to the brachial plexus. Hemi-diaphragmatic paralysis may be well-compensated in healthy individuals at rest but can be associated with persistent exercise intolerance in some patients. This study aims to determine the diagnostic value of inspiratory-expiratory chest radiography compared to intraoperative stimulation of the phrenic nerve for assessing phrenic nerve injury associated with brachial plexus injury. METHODS: Over a 21-year period, the diagnostic utility of three-view inspiratory-expiratory chest radiography for identification of phrenic nerve injury was determined by comparison to intraoperative phrenic nerve stimulation. Multivariate regression analysis was used to identify independent predictors of phrenic nerve injury and having an incorrect radiographic diagnosis. RESULTS: A total of 237 patients with inspiratory-expiratory chest radiography underwent intraoperative testing of phrenic nerve function. Phrenic nerve injury was present in approximately one-fourth of cases. Preoperative chest radiography had a sensitivity of 56%, specificity of 93%, positive predictive negative of 75%, and negative predictive value of 86% for identification of a phrenic nerve palsy. Only C5 avulsion was found to be a predictor of having an incorrect diagnosis of phrenic nerve injury on radiography. CONCLUSION: While inspiratory-expiratory chest radiography has good specificity for detecting phrenic nerve injuries, a high number of false negatives suggest that it should not be relied upon for routine screening of dysfunction after traumatic brachial plexus injury. This is likely multifactorial and relates to variation in diaphragm shape and position, as well as limitations regarding static image interpretation of a dynamic process.

Daily Life Impact of Brachial Plexus Reconstruction in Adults: 10 Years Follow-Up.

PURPOSE: Reconstructive surgery of brachial plexus injury in adults remains a challenge. Short- and midterm follow-up results have been described in terms of impairments, such as muscle strength grading. However, psychologic management has been shown to be a major contributor in long-term results. A new, specific brachial plexus injury scale, including functional and psychologic components, was described. Objectives of this study were: (1) to assess functional long-term brachial plexus reconstruction outcomes; and (2) to validate the Mancuso scale at 10 years of follow-up. METHODS: Twenty patients with at least 10 years of follow-up were included in the study. Four patients had C5-C6 palsy and 16 had a C5-T1 injury. Shoulder abduction and elbow flexion were assessed with Medical Research Council grades. Shoulder function was evaluated with a Constant score. The 36-item short-form survey (SF36) was used to assess quality of life, and the quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) was used for patient reports of disability. The Mancuso scale was assessed and correlated to the different scores used. RESULTS: At the last follow-up, the Medical Research Council grade was at least grade 3 in 10 cases (50%) of shoulder abduction and in 12 cases (60%) of elbow flexion. The Constant score was 31.4 (SD, 15.1). The SF36 score was 67.5 (SD, 4.25) and the QuickDASH was 50 (SD, 15.9). We found a correlation between the symptom score (Mancuso score) and the different quality-of-life scores (QuickDASH: coefficient, 0.491; SF36: coefficient, -0.565; limitations score: coefficient, 0.445). CONCLUSIONS: This study reported results from the Mancuso scale at a minimum of 10 years of follow-up of reconstructive surgery for brachial plexus injury in adults. Correlations between this composite scale and the SF36 and QuickDASH scores suggest construct validity. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

End-to-Side vs. Free Graft Nerve Reconstruction-Experimental Study on Rats.

The long history of regeneration nerve research indicates many clinical problems with surgical reconstruction to be resolved. One of the promising surgical techniques in specific clinical conditions is end-to-side neurorrhaphy (ETS), described and then repeated with different efficiency in the 1990s of the twentieth century. There are no reliable data on the quality of recipient nerve regeneration, possible donor nerve damage, and epineural window technique necessary to be performed. This research attempts to evaluate the possible regeneration after end-to-side neurorrhaphy, its quality, potential donor nerve damage, and the influence of epineural windows on regeneration efficiency. Forty-five female Wistar rats were divided into three equal groups, and various surgical technics were applied: A-ETS without epineural window, B-ETS with epineural window, and C-free graft reconstruction. The right peroneal nerve was operated on, and the tibial nerve was selected as a donor. After 24 weeks, the regeneration was evaluated by (1) footprint analysis every two weeks with PFI (peroneal nerve function index), TFI (tibial nerve function index), and SFI (sciatic nerve function index) calculations; (2) the amplitude and latency measurements of motor evoked potentials parameters recorded on both sides of the peroneal and tibial nerves when electroneurography with direct sciatic nerve electrical stimulation and indirect magnetic stimulation were applied; (3) histomorphometry with digital conversion of a transverse semithin nerve section, with axon count, fibers diameter, and calculation of axon area with a semiautomated method were performed. There was no statistically significant difference between the groups investigated in all the parameters. The functional indexes stabilized after eight weeks (PFI) and six weeks (TFI and SFI) and were positively time related. The lower amplitude of tibial nerve potential in groups A and B was proven compared to the non-operated side. Neurophysiological parameters of the peroneal nerve did not differ significantly. Histomorphometry revealed significantly lower diameter and area of axons in operated peroneal nerves compared to non-operated nerves. The axon count was at a normal level in every group. Tibial nerve parameters did not differ from non-operated values. Regeneration of the peroneal nerve after ETS was ascertained to be at the same level as in the case of free graft reconstruction. Peroneal nerves after ETS and free graft reconstruction were ascertained to have a lower diameter and area than non-operated ones. The technique of an epineural window does not influence the regeneration result of the peroneal nerve. The tibial nerve motor evoked potentials were characterized by lower amplitudes in ETS groups, which could indicate axonal impairment.

The Dynamics of Nerve Degeneration and Regeneration in a Healthy Milieu and in Diabetes.

Appropriate animal models, mimicking conditions of both health and disease, are needed to understand not only the biology and the physiology of neurons and other cells under normal conditions but also under stress conditions, like nerve injuries and neuropathy. In such conditions, understanding how genes and different factors are activated through the well-orchestrated programs in neurons and other related cells is crucial. Knowledge about key players associated with nerve regeneration intended for axonal outgrowth, migration of Schwann cells with respect to suitable substrates, invasion of macrophages, appropriate conditioning of extracellular matrix, activation of fibroblasts, formation of endothelial cells and blood vessels, and activation of other players in healthy and diabetic conditions is relevant. Appropriate physical and chemical attractions and repulsions are needed for an optimal and directed regeneration and are investigated in various nerve injury and repair/reconstruction models using healthy and diabetic rat models with relevant blood glucose levels. Understanding dynamic processes constantly occurring in neuropathies, like diabetic neuropathy, with concomitant degeneration and regeneration, requires advanced technology and bioinformatics for an integrated view of the behavior of different cell types based on genomics, transcriptomics, proteomics, and imaging at different visualization levels. Single-cell-transcriptional profile analysis of different cells may reveal any heterogeneity among key players in peripheral nerves in health and disease.

Mechanisms, interventions at risk and clinical presentation of iatrogenic nerve lesions in trauma patients.

BACKGROUND: Iatrogenic nerve lesions during surgical interventions are avoidable complications that may cause severe functional impairment. Hereby, awareness of physicians and knowledge of structures and interventions at risk is of utmost importance for prevention. As current literature is scarce, we evaluated all patients treated surgically due to peripheral nerve injuries in our specialized nerve center for the presence of iatrogenic nerve lesions. METHODS: We evaluated a total of 5026 patients with peripheral nerve injuries treated over a time period of 8 years in our facility for the prevalence of iatrogenic nerve injuries, their clinical presentations, time to treatment, mechanisms and intraoperative findings on nerve continuity. RESULTS: A total of 360 (6.1%) patients had an iatrogenic cause resulting in 380 injured nerves. 76.6% of these lesions affected the main branch of the injured nerve, which were mainly the radial (30.5%), peroneal (13.7%) and median nerve (10.3%). After a mean delay of 237 ± 344 days, patients presented 23.2% with a motor and 27.9% with a mixed sensory and motor deficit. 72.6% of lesions were in-continuity lesions. Main interventions at risk are displayed for every nerve, frequently concerning osteosyntheses but also patient positioning and anesthesiologic interventions. DISCUSSION: Awareness of major surgical complications such as iatrogenic nerve injuries is important for surgeons. An often-seen trivialization or "watch and wait" strategy results in a huge delay for starting an adequate therapy. The high number of in-continuity lesions mainly in close proximity to osteosyntheses makes diagnosis and treatment planning a delicate challenge, especially due to the varying clinical presentations we found. Diagnostics and therapy should therefore be performed as early as possible in specialized centers capable of performing nerve repair as well as salvage therapies.

Advantages of simultaneous radial nerve and tendon reconstruction - a case report.

Transection of the radial nerve is frequently associated with humeral shaft fractures that are part of a very complex upper extremity injury. In the presented case, a 19-year-old man with a 10-cm radial nerve defect with a need for nerve grafting to recover complete sensory and motor deficit of the radial nerve. In our case, at the same time we provided the tendon transfer of musculus (m.) pronator teres to m. extensor carpi radialis brevis, m. flexor carpi ulnaris to m. extensor digitorum communis, m. palmaris longus to m. extensor pollicis longus, and long sural nerve graft because of an extensive zone of the injury. The assumption was that if these two procedures are performed in one surgery, it will accelerate overall recovery, restore the functionality of the upper limb more quickly, and thus enable a faster recovery.

Improving outcomes in traumatic peripheral nerve injuries to the upper extremity.

Peripheral nerve lesions of the upper extremity are common and are associated with devastating limitations for the patient. Rapid and accurate diagnosis of the lesion by electroneurography, neurosonography, or even MR neurography is important for treatment planning. There are different therapeutic approaches, which may show individual differences depending on the injured nerve. If a primary nerve repair is not possible, several strategies exist to bridge the gap. These may include autologous nerve grafts, bioartificial nerve conduits, or acellular nerve allografts. Tendon and nerve transfers are also of major importance in the treatment of nerve lesions in particular with long regeneration distances. As a secondary reconstruction, in addition to tendon transfers, there is also the option for free functional muscle transfer. In amputations, the prevention of neuroma is of great importance, for which different strategies exist, such as target muscle reinnervation, regenerative peripheral nerve interface, or neurotized flaps. In this article, we give an overview of the latest methods for the therapy of peripheral nerve lesions.

Evaluation of the Induced Membrane for Neurotrophic Factors.

PURPOSE: Despite gaining popularity as a bridge for small and moderate nerve gaps, an acellular nerve allograft (ANA) lacks many of the neurotrophic characteristics of a nerve autograft. Pseudomembranes induced to form around temporary skeletal spacers are rich in growth factors. Induced membranes may have beneficial neurotrophic factors which could support ANA. METHODS: Twenty-two male Sprague-Dawley rats underwent resection of 2 cm of the sciatic nerve. A silicone rod was inset in the defect of 11 experimental rats, and marking sutures only were placed in the nerve stumps of the remaining 11 control rats. After allowing 4 weeks for tissue maturation, tissue samples harvested from the induced membrane (experimental group) and the tissue bed (control group) were analyzed using Luminex multiplex assay to quantify differences in detectable levels of the following neurotrophic factors: nerve growth factor, glial-derived nerve factor, vascular endothelial growth factor, and transforming growth factor ß (TGF-ß) 1, 2, and 3, interleukin-1ß, and monocyte chemoattractant protein 1. RESULTS: No difference was detected between the control and experimental groups in levels of vascular endothelial growth factor. Higher levels of TGF-ß1, TGF-ß2, TGF-ß3, glial-derived nerve factor, nerve growth factor, monocyte chemoattractant protein 1, and interleukin-1ß were detected in the experimental group. CONCLUSIONS: In the setting of peripheral nerve injury, an induced membrane has higher levels of several neurotrophic factors that may support nerve regeneration compared to wound bed cicatrix. CLINICAL RELEVANCE: This investigation provides impetus for further study examining the utility of using a staged induced membrane technique in conjunction with delayed nerve grafting in reconstruction of some peripheral nerve defects.

Nerve transfers to restore femoral nerve function following oncologic nerve resection.

INTRODUCTION: Advances in the care of soft-tissue tumors, including imaging capabilities and adjuvant radiation therapy, have broadened the indications and opportunities to pursue surgical limb salvage. However, peripheral nerve involvement and femoral nerve resection can still result in devastating functional outcomes. Nerve transfers offer a versatile solution to restore nerve function following tumor resection. METHODS: Two cases were identified by retrospective review. Patient and disease characteristics were gathered. Preoperative and postoperative motor function were assessed using the Medical Research Council Muscle Scale. Patient-reported pain levels were assessed using the numeric rating scale. RESULTS: Nerve transfers from the obturator and sciatic nerve were employed to restore knee extension. Follow up for Case 1 was 24 months, 8 months for Case 2. In both patients, knee extension and stabilization of gait without bracing was restored. Patient also demonstrated 0/10 pain (an average improvement of 5 points) with decreased neuromodulator and pain medication use. CONCLUSION: Nerve transfers can restore function and provide pain control benefits and ideally are performed at the time of tumor extirpation. This collaboration between oncologic and nerve surgeons will ultimately result in improved functional recovery and patient outcomes.

Surgical Neuropelveology: Lateral Femoral Cutaneous Nerve Endometriosis. Laparoscopic Resection and Nerve Transplantation.

STUDY OBJECTIVE: To demonstrate the application of surgical neuroanatomic principles for the diagnosis and treatment of deep infiltrating endometriosis involving the lateral femoral cutaneous nerve. DESIGN: Video demonstration of laparoscopic lateral femoral cutaneous endometriosis resection with nerve transplant. SETTING: Endometriosis infiltrating somatic nerves is a poorly known condition, which can cause severe neuropathic symptoms [1] and is often unrecognized with a subsequent treatment delay [1]. Intimate knowledge of pelvic neuroanatomy and expertise in minimally invasive surgery are essential to manage this challenging surgical scenario [2-4]. INTERVENTIONS: Thirty-six years old patient with primary infertility and chronic pelvic pain associated with dysmenorrhea, dyspareunia, dysuria, and dyschezia. Preoperative magnetic resonance imaging detected a 3-cm parauterine and a 2-cm retrocervical endometriosis nodule. Magnetic resonance imaging did not demonstrate pelvic nerve involvement. Preoperative neuropelveologic assessment demonstrated a significant hypoesthesia of the corresponding lateral femoral cutaneous nerve dermatome, representing the primary complaint. A swab test showed spotting areas of allodynia. These findings prompted us to investigate for a right lateral femoral cutaneous entrapment. Laparoscopy showed an endometriosis nodule infiltrating the right lateral femoral cutaneous nerve. A resection of the nerve was necessary, and a subsequent reconstruction with a collagen bovine neuro-guide was carried out. The operative time was 300 minutes, and the estimated blood loss was 150 mL. Hospital stay was 3 days. After 3 months, the patient showed a clinical improvement in the pain and hypoesthesia on the reconstructed nerve dermatome. CONCLUSION: Neuropelvic anatomic assessment should be considered during the preoperative evaluation for patients with endometriosis who have pelvic pain and neuropathy as part of the diagnostic process [5]. This unique case demonstrates that nerve resection and transplantation can be used in specific situations for neuropathy related to deep infiltrative endometriosis of pelvic nerves.

Management of Adult Brachial Plexus Injuries.

Adult brachial plexus injuries result in profound functional deficits, debilitating pain, substantial mental health implications, and extensive economic impacts. Their initial evaluation includes a detailed physical examination, electrodiagnostic studies, advanced imaging, and patient counseling. A team-based approach, led by a peripheral nerve surgeon and including hand therapists, electrodiagnosticians, mental health experts, and pain-management specialists, is used to provide optimal longitudinal care during the lengthy recovery process. The options for the surgical management of brachial plexus injuries include exploration, neurolysis, nerve grafting, nerve transfer, free functional muscle transfer, tendon transfer, arthrodesis, and amputation. When treated within 6 months, the outcomes are favorable for the restoration of essential shoulder and elbow function. Free functional muscle transfer is a powerful tool to address elbow flexion and rudimentary grasp in both primary and delayed settings. The restoration of hand function remains a challenge for patients with complete brachial plexus injury. The purpose of this review is to summarize foundational concepts in diagnosis and management, discuss current trends and controversial topics, and address areas for future investigation.

Bioactive Nanofiber-Based Conduits in a Peripheral Nerve Gap Management-An Animal Model Study.

The aim was to examine the efficiency of a scaffold made of poly (L-lactic acid)-co-poly(ϵ-caprolactone), collagen (COL), polyaniline (PANI), and enriched with adipose-derived stem cells (ASCs) as a nerve conduit in a rat model. P(LLA-CL)-COL-PANI scaffold was optimized and electrospun into a tubular-shaped structure. Adipose tissue from 10 Lewis rats was harvested for ASCs culture. A total of 28 inbred male Lewis rats underwent sciatic nerve transection and excision of a 10 mm nerve trunk fragment. In Group A, the nerve gap remained untouched; in Group B, an excised trunk was used as an autograft; in Group C, nerve stumps were secured with P(LLA-CL)-COL-PANI conduit; in Group D, P(LLA-CL)-COL-PANI conduit was enriched with ASCs. After 6 months of observation, rats were sacrificed. Gastrocnemius muscles and sciatic nerves were harvested for weight, histology analysis, and nerve fiber count analyses. Group A showed advanced atrophy of the muscle, and each intervention (B, C, D) prevented muscle mass decrease (p < 0.0001); however, ASCs addition decreased efficiency vs. autograft (p < 0.05). Nerve fiber count revealed a superior effect in the nerve fiber density observed in the groups with the use of conduit (D vs. B p < 0.0001, C vs. B p < 0.001). P(LLA-CL)-COL-PANI conduits with ASCs showed promising results in managing nerve gap by decreasing muscle atrophy.

Polymer Scaffolds for Biomedical Applications in Peripheral Nerve Reconstruction.

The nervous system is a significant part of the human body, and peripheral nerve injury caused by trauma can cause various functional disorders. When the broken end defect is large and cannot be repaired by direct suture, small gap sutures of nerve conduits can effectively replace nerve transplantation and avoid the side effect of donor area disorders. There are many choices for nerve conduits, and natural materials and synthetic polymers have their advantages. Among them, the nerve scaffold should meet the requirements of good degradability, biocompatibility, promoting axon growth, supporting axon expansion and regeneration, and higher cell adhesion. Polymer biological scaffolds can change some shortcomings of raw materials by using electrospinning filling technology and surface modification technology to make them more suitable for nerve regeneration. Therefore, polymer scaffolds have a substantial prospect in the field of biomedicine in future. This paper reviews the application of nerve conduits in the field of repairing peripheral nerve injury, and we discuss the latest progress of materials and fabrication techniques of these polymer scaffolds.

A Multicenter Matched Cohort Study of Processed Nerve Allograft and Conduit in Digital Nerve Reconstruction.

PURPOSE: Biomaterials used to restore digital nerve continuity after injury associated with a defect may influence ultimate outcomes. An evaluation of matched cohorts undergoing digital nerve gap reconstruction was conducted to compare processed nerve allograft (PNA) and conduits. Based on scientific evidence and historical controls, we hypothesized that outcomes of PNA would be better than for conduit reconstruction. METHODS: We identified matched cohorts based on patient characteristics, medical history, mechanism of injury, and time to repair for digital nerve injuries with gaps up to 25 mm. Data were stratified into 2 gap length groups: short gaps of 14 mm or less and long gaps of 15 to 25 mm. Meaningful sensory recovery was defined as a Medical Research Council scale of S3 or greater. Comparisons of meaningful recovery were made by repair method between and across the gap length groups. RESULTS: Eight institutions contributed matched data sets for 110 subjects with 162 injuries. Outcomes data were available in 113 PNA and 49 conduit repairs. Meaningful recovery was reported in 61% of the conduit group, compared with 88% in the PNA group. In the group with a 14-mm or less gap, conduit and PNA outcomes were 67% and 92% meaningful recovery, respectively. In the 15- to 25-mm gap length group, conduit and PNA outcomes were 45% and 85% meaningful recovery, respectively. There were no reported adverse events in either treatment group. CONCLUSIONS: Outcomes of digital nerve reconstruction in this study using PNA were consistent and significantly better than those of conduits across all groups. As gap lengths increased, the proportion of patients in the conduit group with meaningful recovery decreased. This study supports the use of PNA for nerve gap reconstruction in digital nerve reconstructions up to 25 mm. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

Prognostic value of needle electromyography in traumatic brachial plexus injury.

INTRODUCTION: In this study we aimed to determine whether needle electromyographic assessment of voluntary motor unit recruitment in traumatic brachial plexus injuries could predict spontaneous motor recovery. METHODS: A retrospective study was performed on patients with brachial plexus injury affecting deltoid, supraspinatus/infraspinatus, and biceps brachii. The outcome measure was strength on manual muscle testing at least 1 year after injury. Good outcome was considered strength >3/5 on the Medical Research Council (MRC) scale. RESULTS: No muscles with no recruitment (n = 27) at 1-9 months improved to MRC 4/5 strength at a mean of 2.0 years postinjury. Twenty-five percent of muscles with discrete or severely reduced recruitment (n = 8) regained strength to >3/5 at a mean of 1.4 years postinjury (P = .047). DISCUSSION: Absent voluntary motor unit potential recruitment at 1-9 months predicted poor prognosis for spontaneous recovery. A high percentage of patients with discrete recruitment did not improve to >3/5 strength. These patients should be considered for early nerve transfer surgery.

Reconstruction of complex defects of the extracranial facial nerve: technique of "the trifurcation approach".

PURPOSE: Reconstruction of complex defects of facial nerve (FN) after extensive cancer surgery requires individualized solutions. We describe the trifurcation technique as a modification of the combined approach on example of two patients with locally advanced parotid cancer. METHODS: Due to perineural invasion, extensive resection of the FN from the mastoid segment to the peripheral branches was required. For reanimation of the upper face, a complex cervical plexus graft was sutured end-to-end to the mastoid segment of the FN trunk. The branches of the graft enabled reanimation of three peripheral temporal and zygomatic branches. The mandibular branch was sutured end-to-side to the hypoglossal nerve (hypoglossal-facial nerve transfer, HFNT). Additionally, the buccal branch was independently reanimated with ansa cervicalis. RESULTS: Facial reanimation was successful in both patients. Good resting tone and voluntary movement were achieved with a mild degree of synkinesis after 13 months. Patient 1 showed the Sunnybrook (SB) composite score 69 [76 (voluntary movement score) - 0 (resting symmetry score) - 7 (synkinesis score)]. In patient 2, the SB composite score was 76 (80 - 0 - 4, respectively). CONCLUSIONS: In this trifurcation approach, cervical cutaneous plexus provides a long complex nerve graft, which allows bridging the gap between proximal FN stump and several peripheral branches without great expenditure. In combination with the HFNT and ansa cervicalis transfer, this procedure enables the facial reanimation with low grade of synkinesis.

Management of the facial nerve in parotid cancer: preservation or resection and reconstruction.

PURPOSE: Management of the facial nerve is instrumental in the surgical treatment of parotid cancer. METHODS: A literature search was conducted using PubMed and ScienceDirect database. A total of 195 articles were finally included into the analysis, based on relevance, scientific evidence and actuality. RESULTS: In the majority of cases the facial nerve is not involved by tumor. In these cases, identification and preservation of the nerve, in addition to complete tumor removal, are essential for successful surgery. When the nerve is infiltrated by tumor, the affected portion of the nerve must be resected as part of radical parotidectomy. Primary nerve reconstruction or other reanimation techniques give the best long-term functional and cosmetic results. A comprehensive diagnostic evaluation with current imaging and electrophysiological studies will provide the surgeon with the best knowledge of the relationship of the facial nerve to the tumor. Several standardized methods are helpful in finding, dissecting and preserving the nerve during parotid cancer surgery. When radical parotidectomy is indicated, the initial diagnostic work-up can assist in defining the need for adjuvant postoperative therapy and facial reanimation. The aim of rehabilitation is to restore tone, symmetry, and movement to the paralyzed face. CONCLUSIONS: The surgical management of facial paralysis has undergone many improvements in recent years. This review gives an overview of recent advances in the diagnostic work-up, surgical techniques and any necessary rehabilitation of the facial nerve in parotid cancer surgery.

Co-Culturing Human Adipose Derived Stem Cells and Schwann Cells on Spider Silk-A New Approach as Prerequisite for Enhanced Nerve Regeneration.

Fast recovery is crucial for a successful nerve repair and an optimal functional outcome after peripheral nerve injury. Regarding donor site morbidity, autologous transplantation shows great limitations, which urge the need for alternative options in nerve reconstruction. Spider silk was reported as an advantageous material for cell adhesion, migration and proliferation, and its use in conduits is of great interest, especially in combination with cells to improve nerve regeneration. We here described the behavior of a co-culture of human Schwann cells and human adipose-derived stem cells (ADSCs) on spider silk as a new approach. After characterized by immunostaining ADSCs and Schwann cells were seeded in the co-culture on a spider silk scaffold and observed for 21 days. Results showed that cells were attached to the silk and aligned along the silk fibers. With further culture time, cells migrated along the silk and increased in number and formed an almost confluent cell layer. In immunostaining, results suggest that the cell layer was equally composed of ADSCs and Schwann cells. In conclusion, we showed that by providing a guiding structure for directed growth and cells to support nerve regeneration and remyelination, a valid alternative to autologous nerve grafts could have been found.

Seeding nerve sutures with minced nerve-graft (MINE-G): a simple method to improve nerve regeneration in rats.

BACKGROUND: The aim of this study was to assess the effect of seeding the distal nerve suture with nerve fragments in rats. METHODS: On 20 rats, a 15 mm sciatic nerve defect was reconstructed with a nerve autograft. In the Study Group (10 rats), a minced 1 mm nerve segment was seeded around the nerve suture. In the Control Group (10 rats), a nerve graft alone was used. At 4 and 12 weeks, a walking track analysis with open field test (WTA), hystomorphometry (number of myelinated fibers (n), fiber density (FD) and fiber area (FA) and soleus and gastrocnemius muscle weight ratios (MWR) were evaluated. The Student t-test was used for statistical analysis. RESULTS: At 4 and 12 weeks the Study Group had a significantly higher n and FD (p = .043 and .033). The SMWR was significantly higher in the Study Group at 12 weeks (p = .0207). CONCLUSIONS: Seeding the distal nerve suture with nerve fragments increases the number of myelinated fibers, the FD and the SMWR. The technique seems promising and deserves further investigation to clarify the mechanisms involved and its functional effects.