The role of great auricular-facial nerve neurorrhaphy in facial nerve damage

PubMed Central

Sun, Yan; Liu, Limei; Han, Yuechen; Xu, Lei; Zhang, Daogong; Wang, Haibo

2015-01-01

Background: Facial nerve is easy to be damaged, and there are many reconstructive methods for facial nerve reconstructive, such as facial nerve end to end anastomosis, the great auricular nerve graft, the sural nerve graft, or hypoglossal-facial nerve anastomosis. However, there is still little study about great auricular-facial nerve neurorrhaphy. The aim of the present study was to identify the role of great auricular-facial nerve neurorrhaphy and the mechanism. Methods: Rat models of facial nerve cut (FC), facial nerve end to end anastomosis (FF), facial-great auricular neurorrhaphy (FG), and control (Ctrl) were established. Apex nasi amesiality observation, electrophysiology and immunofluorescence assays were employed to investigate the function and mechanism. Results: In apex nasi amesiality observation, it was found apex nasi amesiality of FG group was partly recovered. Additionally, electrophysiology and immunofluorescence assays revealed that facial-great auricular neurorrhaphy could transfer nerve impulse and express AChR which was better than facial nerve cut and worse than facial nerve end to end anastomosis. Conclusions: The present study indicated that great auricular-facial nerve neurorrhaphy is a substantial solution for facial lesion repair, as it is efficiently preventing facial muscles atrophy by generating neurotransmitter like ACh. PMID:26550216

[Facial nerve neurinomas].

PubMed

Sokołowski, Jacek; Bartoszewicz, Robert; Morawski, Krzysztof; Jamróz, Barbara; Niemczyk, Kazimierz

2013-01-01

Evaluation of diagnostic, surgical technique, treatment results facial nerve neurinomas and its comparison with literature was the main purpose of this study. Seven cases of patients (2005-2011) with facial nerve schwannomas were included to retrospective analysis in the Department of Otolaryngology, Medical University of Warsaw. All patients were assessed with history of the disease, physical examination, hearing tests, computed tomography and/or magnetic resonance imaging, electronystagmography. Cases were observed in the direction of potential complications and recurrences. Neurinoma of the facial nerve occurred in the vertical segment (n=2), facial nerve geniculum (n=1) and the internal auditory canal (n=4). The symptoms observed in patients were analyzed: facial nerve paresis (n=3), hearing loss (n=2), dizziness (n=1). Magnetic resonance imaging and computed tomography allowed to confirm the presence of the tumor and to assess its staging. Schwannoma of the facial nerve has been surgically removed using the middle fossa approach (n=5) and by antromastoidectomy (n=2). Anatomical continuity of the facial nerve was achieved in 3 cases. In the twelve months after surgery, facial nerve paresis was rated at level II-III° HB. There was no recurrence of the tumor in radiological observation. Facial nerve neurinoma is a rare tumor. Currently surgical techniques allow in most cases, the radical removing of the lesion and reconstruction of the VII nerve function. The rate of recurrence is low. A tumor of the facial nerve should be considered in the differential diagnosis of nerve VII paresis. Copyright © 2013 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

Combinatorial treatments enhance recovery following facial nerve crush.

PubMed

Sharma, Nijee; Moeller, Carl W; Marzo, Sam J; Jones, Kathryn J; Foecking, Eileen M

2010-08-01

To investigate the effects of various combinatorial treatments, consisting of a tapering dose of prednisone (P), a brief period of nerve electrical stimulation (ES), and systemic testosterone propionate (TP) on improving functional recovery following an intratemporal facial nerve crush injury. Prospective, controlled animal study. After a right intratemporal facial nerve crush, adult male Sprague-Dawley rats were divided into the following eight treatment groups: 1) no treatment, 2) P only, 3) ES only, 4) ES + P, 5) TP only, 6) TP + P, 7) ES + TP, and 8) ES + TP + P. For each group n = 4-8. Recovery of the eyeblink reflex and vibrissae orientation and movement were assessed. Changes in peak amplitude and latency of evoked response, in response to facial nerve stimulation, was also recorded weekly. : Brief ES of the proximal nerve stump most effectively accelerated the initiation of functional recovery. Also, ES or TP treatments enhanced recovery of some functional parameters more than P treatment. When administered alone, none of the three treatments improved recovery of complete facial function. Only the combinatorial treatment of ES + TP, regardless of the presence of P, accelerated complete functional recovery and return of normal motor nerve conduction. Our findings suggest that a combinatorial treatment strategy of using brief ES and TP together promises to be an effective therapeutic intervention for promoting regeneration following facial nerve injury. Administration of P neither augments nor hinders recovery.

Effects of local application of methylprednisolone delivered by the C/GP-hydrogel on the recovery of facial nerves.

PubMed

Chao, Xiuhua; Fan, Zhaomin; Han, Yuechen; Wang, Yan; Li, Jianfeng; Chai, Renjie; Xu, Lei; Wang, Haibo

2015-01-01

Local administration of MP delivered by the C/GP-MP-hydrogel can improve the recovery of facial nerve following crush injury. The findings suggested that locally injected MP delivered by C/GP-hydrogel might be a promising treatment for facial nerve damage. In this study, the aim is to assess the effectiveness of locally administrating methylprednisolone(MP) loaded by chitosan-β-glycerophosphate hydrogel (C/GP-hydrogel) on the regeneration of facial nerve crush injury. After the crush of left facial nerves, Wistar rats were randomly divided into four different groups. Then, four different therapies were used to treat the damaged facial nerves. At the 1(st), 2(nd), 3(rd), and 4(th) week after injury, the functional recovery of facial nerves and the morphological changes of facial nerves were assessed. The expression of growth associated protein-43 (GAP-43) protein in the facial nucleus were also evaluated. Locally injected MP delivered by C/GP-hydrogel effectively accelerated the facial functional recovery. In addition, the regenerated facial nerves in the C/GP-MP group were more mature than those in the other groups. The expression of GAP-43 protein was also improved by the MP, especially in the C/GP-MP group.

Long-term functional recovery after facial nerve transection and repair in the rat.

PubMed

Banks, Caroline A; Knox, Christopher; Hunter, Daniel A; Mackinnon, Susan E; Hohman, Marc H; Hadlock, Tessa A

2015-03-01

The rodent model is commonly used to study facial nerve injury. Because of the exceptional regenerative capacity of the rodent facial nerve, it is essential to consider the timing when studying facial nerve regeneration and functional recovery. Short-term functional recovery data following transection and repair of the facial nerve has been documented by our laboratory. However, because of the limitations of the head fixation device, there is a lack of long-term data following facial nerve injury. The objective of this study was to elucidate the long-term time course and functional deficit following facial nerve transection and repair in a rodent model. Adult rats were divided into group 1 (controls) and group 2 (experimental). Group 1 animals underwent head fixation, followed by a facial nerve injury, and functional testing was performed from day 7 to day 70. Group 2 animals underwent facial nerve injury, followed by delayed head fixation, and then underwent functional testing from months 6 to 8. There was no statistical difference between the average whisking amplitudes in group 1 and group 2 animals. Functional whisking recovery 6 months after facial nerve injury is comparable to recovery within 1 to 4 months of transection and repair, thus the ideal window for evaluating facial nerve recovery falls within the 4 months after injury. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Facial reanimation by muscle-nerve neurotization after facial nerve sacrifice. Case report.

PubMed

Taupin, A; Labbé, D; Babin, E; Fromager, G

2016-12-01

Recovering a certain degree of mimicry after sacrifice of the facial nerve is a clinically recognized finding. The authors report a case of hemifacial reanimation suggesting a phenomenon of neurotization from muscle-to-nerve. A woman benefited from a parotidectomy with sacrifice of the left facial nerve indicated for recurrent tumor in the gland. The distal branches of the facial nerve, isolated at the time of resection, were buried in the masseter muscle underneath. The patient recovered a voluntary hémifacial motricity. The electromyographic analysis of the motor activity of the zygomaticus major before and after block of the masseter nerve showed a dependence between mimic muscles and the masseter muscle. Several hypotheses have been advanced to explain the spontaneous reanimation of facial paralysis. The clinical case makes it possible to argue in favor of muscle-to-nerve neurotization from masseter muscle to distal branches of the facial nerve. It illustrates the quality of motricity that can be obtained thanks to this procedure. The authors describe a simple implantation technique of distal branches of the facial nerve in the masseter muscle during a radical parotidectomy with facial nerve sacrifice and recovery of resting tone but also a quality voluntary mimicry. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Chondromyxoid fibroma of the mastoid facial nerve canal mimicking a facial nerve schwannoma.

PubMed

Thompson, Andrew L; Bharatha, Aditya; Aviv, Richard I; Nedzelski, Julian; Chen, Joseph; Bilbao, Juan M; Wong, John; Saad, Reda; Symons, Sean P

2009-07-01

Chondromyxoid fibroma of the skull base is a rare entity. Involvement of the temporal bone is particularly rare. We present an unusual case of progressive facial nerve paralysis with imaging and clinical findings most suggestive of a facial nerve schwannoma. The lesion was tubular in appearance, expanded the mastoid facial nerve canal, protruded out of the stylomastoid foramen, and enhanced homogeneously. The only unusual imaging feature was minor calcification within the tumor. Surgery revealed an irregular, cystic lesion. Pathology diagnosed a chondromyxoid fibroma involving the mastoid portion of the facial nerve canal, destroying the facial nerve.

Quantitative facial electromyography monitoring after hypoglossal‐facial jump nerve suture

PubMed Central

Flasar, Jan; Volk, Gerd Fabian; Granitzka, Thordis; Geißler, Katharina; Irintchev, Andrey; Lehmann, Thomas

2017-01-01

Objectives/Hypothesis The time course of the reinnervation of the paralyzed face after hypoglossal‐facial jump nerve suture using electromyography (EMG) was assessed. The relation to the clinical outcome was analyzed. Study Design Retrospective single‐center cohort study Methods Reestablishment of motor units was studied by quantitative EMG and motor unit potential (MUP) analysis in 11 patients after hypoglossal‐facial jump nerve suture. Functional recovery was evaluated using the Stennert index (0 = normal; 10 = maximal palsy). Results Clinically, first movements were seen between 6 and >10 months after surgery in individual patients. Maximal improvement was achieved at 18 months. The Stennert index decreased from 7.9 ± 2.0 preoperatively to a final postoperative score of 5.8 ± 2.4. EMG monitoring performed for 2.8 to 60 months after surgery revealed that pathological spontaneous activity disappeared within 2 weeks. MUPs were first recorded after the 2nd month and present in all 11 patients 8–10 months post‐surgery. Polyphasic regeneration potentials first appeared at 4–10 months post‐surgery. The MUP amplitudes increased between the 3rd and 15th months after surgery to values of control muscles. The MUP duration was significantly increased above normal values between the 3rd and 24th months after surgery. Conclusion Reinnervation can be detected at least 2 months earlier by EMG than by clinical evaluation. Changes should be followed for at least 18 months to assess outcome. EMG changes reflected the remodeling of motor units due to axonal regeneration and collateral sprouting by hypoglossal nerve fibers into the reinnervated facial muscle fibers. Level of Evidence 3b. PMID:29094077

Traumatic facial nerve neuroma with facial palsy presenting in infancy.

PubMed

Clark, James H; Burger, Peter C; Boahene, Derek Kofi; Niparko, John K

2010-07-01

To describe the management of traumatic neuroma of the facial nerve in a child and literature review. Sixteen-month-old male subject. Radiological imaging and surgery. Facial nerve function. The patient presented at 16 months with a right facial palsy and was found to have a right facial nerve traumatic neuroma. A transmastoid, middle fossa resection of the right facial nerve lesion was undertaken with a successful facial nerve-to-hypoglossal nerve anastomosis. The facial palsy improved postoperatively. A traumatic neuroma should be considered in an infant who presents with facial palsy, even in the absence of an obvious history of trauma. The treatment of such lesion is complex in any age group but especially in young children. Symptoms, age, lesion size, growth rate, and facial nerve function determine the appropriate management.

Unilateral Multiple Facial Nerve Branch Reconstruction Using “End-to-side Loop Graft” Supercharged by Hypoglossal Nerve

PubMed Central

Sasaki, Ryo; Takeuchi, Yuichi; Watanabe, Yorikatsu; Niimi, Yosuke; Sakurai, Hiroyuki; Miyata, Mariko; Yamato, Masayuki

2014-01-01

Background: Extensive facial nerve defects between the facial nerve trunk and its branches can be clinically reconstructed by incorporating double innervation into an end-to-side loop graft technique. This study developed a new animal model to evaluate the technique’s ability to promote nerve regeneration. Methods: Rats were divided into the intact, nonsupercharge, and supercharge groups. Artificially created facial nerve defects were reconstructed with a nerve graft, which was end-to-end sutured from proximal facial nerve stump to the mandibular branch (nonsupercharge group), or with the graft of which other end was end-to-side sutured to the hypoglossal nerve (supercharge group). And they were evaluated after 30 weeks. Results: Axonal diameter was significantly larger in the supercharge group than in the nonsupercharge group for the buccal (3.78 ± 1.68 vs 3.16 ± 1.22; P < 0.0001) and marginal mandibular branches (3.97 ± 2.31 vs 3.46 ± 1.57; P < 0.0001), but the diameter was significantly larger in the intact group for all branches except the temporal branch. In the supercharge group, compound muscle action potential amplitude was significantly higher than in the nonsupercharge group (4.18 ± 1.49 mV vs 1.87 ± 0.37 mV; P < 0.0001) and similar to that in the intact group (4.11 ± 0.68 mV). Retrograde labeling showed that the mimetic muscles were double-innervated by facial and hypoglossal nerve nuclei in the supercharge group. Conclusions: Multiple facial nerve branch reconstruction with an end-to-side loop graft was able to achieve axonal distribution. Additionally, axonal supercharge from the hypoglossal nerve significantly improved outcomes. PMID:25426357

Facial Nerve Paralysis due to a Pleomorphic Adenoma with the Imaging Characteristics of a Facial Nerve Schwannoma

PubMed Central

Nader, Marc-Elie; Bell, Diana; Sturgis, Erich M.; Ginsberg, Lawrence E.; Gidley, Paul W.

2014-01-01

Background Facial nerve paralysis in a patient with a salivary gland mass usually denotes malignancy. However, facial paralysis can also be caused by benign salivary gland tumors. Methods We present a case of facial nerve paralysis due to a benign salivary gland tumor that had the imaging characteristics of an intraparotid facial nerve schwannoma. Results The patient presented to our clinic 4 years after the onset of facial nerve paralysis initially diagnosed as Bell palsy. Computed tomography demonstrated filling and erosion of the stylomastoid foramen with a mass on the facial nerve. Postoperative histopathology showed the presence of a pleomorphic adenoma. Facial paralysis was thought to be caused by extrinsic nerve compression. Conclusions This case illustrates the difficulty of accurate preoperative diagnosis of a parotid gland mass and reinforces the concept that facial nerve paralysis in the context of salivary gland tumors may not always indicate malignancy. PMID:25083397

Facial Nerve Paralysis due to a Pleomorphic Adenoma with the Imaging Characteristics of a Facial Nerve Schwannoma.

PubMed

Nader, Marc-Elie; Bell, Diana; Sturgis, Erich M; Ginsberg, Lawrence E; Gidley, Paul W

2014-08-01

Background Facial nerve paralysis in a patient with a salivary gland mass usually denotes malignancy. However, facial paralysis can also be caused by benign salivary gland tumors. Methods We present a case of facial nerve paralysis due to a benign salivary gland tumor that had the imaging characteristics of an intraparotid facial nerve schwannoma. Results The patient presented to our clinic 4 years after the onset of facial nerve paralysis initially diagnosed as Bell palsy. Computed tomography demonstrated filling and erosion of the stylomastoid foramen with a mass on the facial nerve. Postoperative histopathology showed the presence of a pleomorphic adenoma. Facial paralysis was thought to be caused by extrinsic nerve compression. Conclusions This case illustrates the difficulty of accurate preoperative diagnosis of a parotid gland mass and reinforces the concept that facial nerve paralysis in the context of salivary gland tumors may not always indicate malignancy.

Repair of facial nerve defects with decellularized artery allografts containing autologous adipose-derived stem cells in a rat model.

PubMed

Sun, Fei; Zhou, Ke; Mi, Wen-Juan; Qiu, Jian-Hua

2011-07-20

The purpose of this study was to investigate the effects of a decellularized artery allograft containing autologous adipose-derived stem cells (ADSCs) on an 8-mm facial nerve branch lesion in a rat model. At 8 weeks postoperatively, functional evaluation of unilateral vibrissae movements, morphological analysis of regenerated nerve segments and retrograde labeling of facial motoneurons were all analyzed. Better regenerative outcomes associated with functional improvement, great axonal growth, and improved target reinnervation were achieved in the artery-ADSCs group (2), whereas the cut nerves sutured with artery conduits alone (group 1) achieved inferior restoration. Furthermore, transected nerves repaired with nerve autografts (group 3) resulted in significant recovery of whisking, maturation of myelinated fibers and increased number of labeled facial neurons, and the latter two parameters were significantly different from those of group 2. Collectively, though our combined use of a decellularized artery allograft with autologous ADSCs achieved regenerative outcomes inferior to a nerve autograft, it certainly showed a beneficial effect on promoting nerve regeneration and thus represents an alternative approach for the reconstruction of peripheral facial nerve defects. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Imaging the Facial Nerve: A Contemporary Review

PubMed Central

Gupta, Sachin; Mends, Francine; Hagiwara, Mari; Fatterpekar, Girish; Roehm, Pamela C.

2013-01-01

Imaging plays a critical role in the evaluation of a number of facial nerve disorders. The facial nerve has a complex anatomical course; thus, a thorough understanding of the course of the facial nerve is essential to localize the sites of pathology. Facial nerve dysfunction can occur from a variety of causes, which can often be identified on imaging. Computed tomography and magnetic resonance imaging are helpful for identifying bony facial canal and soft tissue abnormalities, respectively. Ultrasound of the facial nerve has been used to predict functional outcomes in patients with Bell's palsy. More recently, diffusion tensor tractography has appeared as a new modality which allows three-dimensional display of facial nerve fibers. PMID:23766904

Reconstruction of facial nerve injuries in children.

PubMed

Fattah, Adel; Borschel, Gregory H; Zuker, Ron M

2011-05-01

Facial nerve trauma is uncommon in children, and many spontaneously recover some function; nonetheless, loss of facial nerve activity leads to functional impairment of ocular and oral sphincters and nasal orifice. In many cases, the impediment posed by facial asymmetry and reduced mimetic function more significantly affects the child's psychosocial interactions. As such, reconstruction of the facial nerve affords great benefits in quality of life. The therapeutic strategy is dependent on numerous factors, including the cause of facial nerve injury, the deficit, the prognosis for recovery, and the time elapsed since the injury. The options for treatment include a diverse range of surgical techniques including static lifts and slings, nerve repairs, nerve grafts and nerve transfers, regional, and microvascular free muscle transfer. We review our strategies for addressing facial nerve injuries in children.

Brief electrical stimulation after facial nerve transection and neurorrhaphy: a randomized prospective animal study.

PubMed

Mendez, Adrian; Seikaly, Hadi; Biron, Vincent L; Zhu, Lin Fu; Côté, David W J

2016-02-01

Recent studies have examined the effects of brief electrical stimulation (BES) on nerve regeneration, with some suggesting that BES accelerates facial nerve recovery. However, the facial nerve outcome measurement in these studies has not been precise or accurate. The objective of this study is to assess the effect of BES on accelerating facial nerve functional recovery from a transection injury in the rat model. A prospective randomized animal study using a rat model was performed. Two groups of 9 rats underwent facial nerve surgery. Both group 1 and 2 underwent facial nerve transection and repair at the main trunk of the nerve, with group 2 additionally receiving BES on post-operative day 0 for 1 h using an implantable stimulation device. Primary outcome was measured using a laser curtain model, which measured amplitude of whisking at 2, 4, and 6 weeks post-operatively. At week 2, the average amplitude observed for group 1 was 4.4°. Showing a statistically significant improvement over group 1, the group 2 mean was 14.0° at 2 weeks post-operatively (p = 0.0004). At week 4, group 1 showed improvement having an average of 9.7°, while group 2 remained relatively unchanged with an average of 12.8°. Group 1 had an average amplitude of 13.63° at 6-weeks from surgery. Group 2 had a similar increase in amplitude with an average of 15.8°. There was no statistically significant difference between the two groups at 4 and 6 weeks after facial nerve surgery. This is the first study to use an implantable stimulator for serial BES following neurorrhaphy in a validated animal model. Results suggest performing BES after facial nerve transection and neurorrhaphy at the main trunk of the facial nerve is associated with accelerated whisker movement in a rat model compared with a control group.

Facial nerve palsy due to birth trauma

MedlinePlus

Seventh cranial nerve palsy due to birth trauma; Facial palsy - birth trauma; Facial palsy - neonate; Facial palsy - infant ... An infant's facial nerve is also called the seventh cranial nerve. It can be damaged just before or at the time of delivery. ...

Outcome of different facial nerve reconstruction techniques.

PubMed

Mohamed, Aboshanif; Omi, Eigo; Honda, Kohei; Suzuki, Shinsuke; Ishikawa, Kazuo

There is no technique of facial nerve reconstruction that guarantees facial function recovery up to grade III. To evaluate the efficacy and safety of different facial nerve reconstruction techniques. Facial nerve reconstruction was performed in 22 patients (facial nerve interpositional graft in 11 patients and hypoglossal-facial nerve transfer in another 11 patients). All patients had facial function House-Brackmann (HB) grade VI, either caused by trauma or after resection of a tumor. All patients were submitted to a primary nerve reconstruction except 7 patients, where late reconstruction was performed two weeks to four months after the initial surgery. The follow-up period was at least two years. For facial nerve interpositional graft technique, we achieved facial function HB grade III in eight patients and grade IV in three patients. Synkinesis was found in eight patients, and facial contracture with synkinesis was found in two patients. In regards to hypoglossal-facial nerve transfer using different modifications, we achieved facial function HB grade III in nine patients and grade IV in two patients. Facial contracture, synkinesis and tongue atrophy were found in three patients, and synkinesis was found in five patients. However, those who had primary direct facial-hypoglossal end-to-side anastomosis showed the best result without any neurological deficit. Among various reanimation techniques, when indicated, direct end-to-side facial-hypoglossal anastomosis through epineural suturing is the most effective technique with excellent outcomes for facial reanimation and preservation of tongue movement, particularly when performed as a primary technique. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Facial nerve decompression surgery using bFGF-impregnated biodegradable gelatin hydrogel in patients with Bell palsy.

PubMed

Hato, Naohito; Nota, Jumpei; Komobuchi, Hayato; Teraoka, Masato; Yamada, Hiroyuki; Gyo, Kiyofumi; Yanagihara, Naoaki; Tabata, Yasuhiko

2012-04-01

Basic fibroblast growth factor (bFGF) promotes the regeneration of denervated nerves. The aim of this study was to evaluate the regeneration-facilitating effects of novel facial nerve decompression surgery using bFGF in a gelatin hydrogel in patients with severe Bell palsy. Prospective clinical study. Tertiary referral center. Twenty patients with Bell palsy after more than 2 weeks following the onset of severe paralysis were treated with the new procedure. The facial nerve was decompressed between tympanic and mastoid segments via the mastoid. A bFGF-impregnated biodegradable gelatin hydrogel was placed around the exposed nerve. Regeneration of the facial nerve was evaluated by the House-Brackmann (H-B) grading system. The outcomes were compared with the authors' previous study, which reported outcomes of the patients who underwent conventional decompression surgery (n = 58) or conservative treatment (n = 43). The complete recovery (H-B grade 1) rate of the novel surgery (75.0%) was significantly better than the rate of conventional surgery (44.8%) and conservative treatment (23.3%). Every patient in the novel decompression surgery group improved to H-B grade 2 or better even when undergone between 31 and 99 days after onset. Advantages of this decompression surgery are low risk of complications and long effective period after onset of the paralysis. To the authors' knowledge, this is the first clinical report of the efficacy of bFGF using a new drug delivery system in patients with severe Bell palsy.

Structural parameters of collagen nerve grafts influence peripheral nerve regeneration.

PubMed

Stang, Felix; Fansa, Hisham; Wolf, Gerald; Reppin, Michael; Keilhoff, Gerburg

2005-06-01

Large nerve defects require nerve grafts to allow regeneration. To avoid donor nerve problems the concept of tissue engineering was introduced into nerve surgery. However, non-neuronal grafts support axonal regeneration only to a certain extent. They lack viable Schwann cells which provide neurotrophic and neurotopic factors and guide the sprouting nerve. This experimental study used the rat sciatic nerve to bridge 2 cm nerve gaps with collagen (type I/III) tubes. The tubes were different in their physical structure (hollow versus inner collagen skeleton, different inner diameters). To improve regeneration Schwann cells were implanted. After 8 weeks the regeneration process was monitored clinically, histologically and morphometrically. Autologous nerve grafts and collagen tubes without Schwann cells served as control. In all parameters autologous nerve grafts showed best regeneration. Nerve regeneration in a noteworthy quality was also seen with hollow collagen tubes and tubes with reduced lumen, both filled with Schwann cells. The inner skeleton, however, impaired nerve regeneration independent of whether Schwann cells were added or not. This indicates that not only viable Schwann cells are an imperative prerequisite but also structural parameters determine peripheral nerve regeneration.

Surgical Approaches to Facial Nerve Deficits

PubMed Central

Birgfeld, Craig; Neligan, Peter

2011-01-01

The facial nerve is one of the most commonly injured cranial nerves. Once injured, the effects on form, function, and psyche are profound. We review the anatomy of the facial nerve from the brain stem to its terminal branches. We also discuss the physical exam findings of facial nerve injury at various levels. Finally, we describe various reconstructive options for reanimating the face and restoring both form and function. PMID:22451822

Rat Whisker Movement after Facial Nerve Lesion: Evidence for Autonomic Contraction of Skeletal Muscle

PubMed Central

Heaton, James T.; Sheu, Shu-Hsien; Hohman, Marc H.; Knox, Christopher J.; Weinberg, Julie S.; Kleiss, Ingrid J.; Hadlock, Tessa A.

2014-01-01

Vibrissal whisking is often employed to track facial nerve regeneration in rats; however, we have observed similar degrees of whisking recovery after facial nerve transection with or without repair. We hypothesized that the source of non-facial nerve-mediated whisker movement after chronic denervation was from autonomic, cholinergic axons traveling within the infraorbital branch of the trigeminal nerve (ION). Rats underwent unilateral facial nerve transection with repair (N=7) or resection without repair (N=11). Post-operative whisking amplitude was measured weekly across 10 weeks, and during intraoperative stimulation of the ION and facial nerves at ≥18 weeks. Whisking was also measured after subsequent ION transection (N=6) or pharmacologic blocking of the autonomic ganglia using hexamethonium (N=3), and after snout cooling intended to elicit a vasodilation reflex (N=3). Whisking recovered more quickly and with greater amplitude in rats that underwent facial nerve repair compared to resection (P<0.05), but individual rats overlapped in whisking amplitude across both groups. In the resected rats, non-facial-nerve mediated whisking was elicited by electrical stimulation of the ION, temporarily diminished following hexamethonium injection, abolished by transection of the ION, and rapidly and significantly (P<0.05) increased by snout cooling. Moreover, fibrillation-related whisker movements decreased in all rats during the initial recovery period (indicative of reinnervation), but re-appeared in the resected rats after undergoing ION transection (indicative of motor denervation). Cholinergic, parasympathetic axons traveling within the ION innervate whisker pad vasculature, and immunohistochemistry for vasoactive intestinal peptide revealed these axons branching extensively over whisker pad muscles and contacting neuromuscular junctions after facial nerve resection. This study provides the first behavioral and anatomical evidence of spontaneous autonomic innervation

Rat whisker movement after facial nerve lesion: evidence for autonomic contraction of skeletal muscle.

PubMed

Heaton, James T; Sheu, Shu Hsien; Hohman, Marc H; Knox, Christopher J; Weinberg, Julie S; Kleiss, Ingrid J; Hadlock, Tessa A

2014-04-18

Vibrissal whisking is often employed to track facial nerve regeneration in rats; however, we have observed similar degrees of whisking recovery after facial nerve transection with or without repair. We hypothesized that the source of non-facial nerve-mediated whisker movement after chronic denervation was from autonomic, cholinergic axons traveling within the infraorbital branch of the trigeminal nerve (ION). Rats underwent unilateral facial nerve transection with repair (N=7) or resection without repair (N=11). Post-operative whisking amplitude was measured weekly across 10weeks, and during intraoperative stimulation of the ION and facial nerves at ⩾18weeks. Whisking was also measured after subsequent ION transection (N=6) or pharmacologic blocking of the autonomic ganglia using hexamethonium (N=3), and after snout cooling intended to elicit a vasodilation reflex (N=3). Whisking recovered more quickly and with greater amplitude in rats that underwent facial nerve repair compared to resection (P<0.05), but individual rats overlapped in whisking amplitude across both groups. In the resected rats, non-facial-nerve-mediated whisking was elicited by electrical stimulation of the ION, temporarily diminished following hexamethonium injection, abolished by transection of the ION, and rapidly and significantly (P<0.05) increased by snout cooling. Moreover, fibrillation-related whisker movements decreased in all rats during the initial recovery period (indicative of reinnervation), but re-appeared in the resected rats after undergoing ION transection (indicative of motor denervation). Cholinergic, parasympathetic axons traveling within the ION innervate whisker pad vasculature, and immunohistochemistry for vasoactive intestinal peptide revealed these axons branching extensively over whisker pad muscles and contacting neuromuscular junctions after facial nerve resection. This study provides the first behavioral and anatomical evidence of spontaneous autonomic innervation

Nanofiber Nerve Guide for Peripheral Nerve Repair and Regeneration

DTIC Science & Technology

2016-04-01

faster regeneration and functional recovery. Peripheral nerve injury is a common complication of complex tissue trauma and often results in significant...having poor regeneration overall, the areas of regenerating nerve tissue could often be found in sections of the nerve guide where luminal spaces of...conducted in this Aim also provided important insight into the NGC design parameters necessary to allow for maximum nerve tissue ingrowth and regeneration

[Surgical treatment in otogenic facial nerve palsy].

PubMed

Feng, Guo-Dong; Gao, Zhi-Qiang; Zhai, Meng-Yao; Lü, Wei; Qi, Fang; Jiang, Hong; Zha, Yang; Shen, Peng

2008-06-01

To study the character of facial nerve palsy due to four different auris diseases including chronic otitis media, Hunt syndrome, tumor and physical or chemical factors, and to discuss the principles of the surgical management of otogenic facial nerve palsy. The clinical characters of 24 patients with otogenic facial nerve palsy because of the four different auris diseases were retrospectively analyzed, all the cases were performed surgical management from October 1991 to March 2007. Facial nerve function was evaluated with House-Brackmann (HB) grading system. The 24 patients including 10 males and 14 females were analysis, of whom 12 cases due to cholesteatoma, 3 cases due to chronic otitis media, 3 cases due to Hunt syndrome, 2 cases resulted from acute otitis media, 2 cases due to physical or chemical factors and 2 cases due to tumor. All cases were treated with operations included facial nerve decompression, lesion resection with facial nerve decompression and lesion resection without facial nerve decompression, 1 patient's facial nerve was resected because of the tumor. According to HB grade system, I degree recovery was attained in 4 cases, while II degree in 10 cases, III degree in 6 cases, IV degree in 2 cases, V degree in 2 cases and VI degree in 1 case. Removing the lesions completely was the basic factor to the surgery of otogenic facial palsy, moreover, it was important to have facial nerve decompression soon after lesion removal.

Preservation of Facial Nerve Function Repaired by Using Fibrin Glue-Coated Collagen Fleece for a Totally Transected Facial Nerve during Vestibular Schwannoma Surgery

PubMed Central

Choi, Kyung-Sik; Kim, Min-Su; Jang, Sung-Ho

2014-01-01

Recently, the increasing rates of facial nerve preservation after vestibular schwannoma (VS) surgery have been achieved. However, the management of a partially or completely damaged facial nerve remains an important issue. The authors report a patient who was had a good recovery after a facial nerve reconstruction using fibrin glue-coated collagen fleece for a totally transected facial nerve during VS surgery. And, we verifed the anatomical preservation and functional outcome of the facial nerve with postoperative diffusion tensor (DT) imaging facial nerve tractography, electroneurography (ENoG) and House-Brackmann (HB) grade. DT imaging tractography at the 3rd postoperative day revealed preservation of facial nerve. And facial nerve degeneration ratio was 94.1% at 7th postoperative day ENoG. At postoperative 3 months and 1 year follow-up examination with DT imaging facial nerve tractography and ENoG, good results for facial nerve function were observed. PMID:25024825

Deficient functional recovery after facial nerve crush in rats is associated with restricted rearrangements of synaptic terminals in the facial nucleus.

PubMed

Hundeshagen, G; Szameit, K; Thieme, H; Finkensieper, M; Angelov, D N; Guntinas-Lichius, O; Irintchev, A

2013-09-17

Crush injuries of peripheral nerves typically lead to axonotmesis, axonal damage without disruption of connective tissue sheaths. Generally, human patients and experimental animals recover well after axonotmesis and the favorable outcome has been attributed to precise axonal reinnervation of the original peripheral targets. Here we assessed functionally and morphologically the long-term consequences of facial nerve axonotmesis in rats. Expectedly, we found that 5 months after crush or cryogenic nerve lesion, the numbers of motoneurons with regenerated axons and their projection pattern into the main branches of the facial nerve were similar to those in control animals suggesting precise target reinnervation. Unexpectedly, however, we found that functional recovery, estimated by vibrissal motion analysis, was incomplete at 2 months after injury and did not improve thereafter. The maximum amplitude of whisking remained substantially, by more than 30% lower than control values even 5 months after axonotmesis. Morphological analyses showed that the facial motoneurons ipsilateral to injury were innervated by lower numbers of glutamatergic terminals (-15%) and cholinergic perisomatic boutons (-26%) compared with the contralateral non-injured motoneurons. The structural deficits were correlated with functional performance of individual animals and associated with microgliosis in the facial nucleus but not with polyinnervation of muscle fibers. These results support the idea that restricted CNS plasticity and insufficient afferent inputs to motoneurons may substantially contribute to functional deficits after facial nerve injuries, possibly including pathologic conditions in humans like axonotmesis in idiopathic facial nerve (Bell's) palsy. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

Nerve regeneration in nerve grafts conditioned by vibration exposure.

PubMed

Bergman, S; Widerberg, A; Danielsen, N; Lundborg, G; Dahlin, L B

1995-01-01

Regeneration distances were studied in nerves from vibration-exposed limbs. One hind limb of anaesthetized rats was attached to a vibration exciter and exposed to vibration (80 Hz/32 m/s2) for 5 h/day for 2 or 5 days. Seven days after the latest vibration period a 10-mm long nerve graft was taken from the vibrated sciatic nerve and sutured into a corresponding defect in the con-tralateral sciatic nerve and vice versa, thereby creating two different models within the same animal: (i) regeneration from a freshly transected unvibrated nerve into a vibrated graft and (ii) regeneration from a vibrated nerve into a fresh nerve graft (vibrated recipient side). Four, 6 or 8 days postoperatively (p.o.) the distances achieved by the regenerating axons were determined using the pinch reflex test. Two days of vibration did not influence the regeneration, but 5 days of vibration reduced the initial delay period and a slight reduction of regeneration rate was observed. After 5 days of vibration an increased regeneration distance was observed in both models at day 4 p.o. and at day 6 p.o. in vibrated grafts. This study demonstrates that vibration can condition peripheral nerves and this may be caused by local changes in the peripheral nerve trunk and in the neuron itself.

How to Avoid Facial Nerve Injury in Mastoidectomy?

PubMed Central

Ryu, Nam-Gyu

2016-01-01

Unexpected iatrogenic facial nerve paralysis not only affects facial disfiguration, but also imposes a devastating effect on the social, psychological, and economic aspects of an affected person's life at once. The aims of this study were to postulate where surgeons had mistakenly drilled or where obscured by granulations or by fibrous bands and to look for surgical approach with focused on the safety of facial nerve in mastoid surgery. We had found 14 cases of iatrogenic facial nerve injury (IFNI) during mastoid surgery for 5 years in Korea. The medical records of all the patients were obtained and analyzed injured site of facial nerve segment with surgical technique of mastoidectomy. Eleven patients underwent facial nerve exploration and three patients had conservative management. 43% (6 cases) of iatrogenic facial nerve injuries had occurred in tympanic segment, 28.5% (4 cases) of injuries in second genu combined with tympanic segment, and 28.5% (4 cases) of injuries in mastoid segment. Surgeons should try to identify the facial nerve using available landmarks and be kept in mind the anomalies of the facial nerve. With use of intraoperative facial nerve monitoring, the avoidance of in order to avoid IFNI would be possible in more cases. Many authors emphasized the importance of intraoperative facial nerve monitoring, even in primary otologic surgery. However, anatomical understanding of intratemporal landmarks with meticulous dissection could not be emphasized as possible to prevent IFNI. PMID:27626078

Reconstruction of facial nerve after radical parotidectomy.

PubMed

Renkonen, Suvi; Sayed, Farid; Keski-Säntti, Harri; Ylä-Kotola, Tuija; Bäck, Leif; Suominen, Sinikka; Kanerva, Mervi; Mäkitie, Antti A

2015-01-01

Most patients benefitted from immediate facial nerve grafting after radical parotidectomy. Even weak movement is valuable and can be augmented with secondary static operations. Post-operative radiotherapy does not seem to affect the final outcome of facial function. During radical parotidectomy, the sacrifice of the facial nerve results in severe disfigurement of the face. Data on the principles and outcome of facial nerve reconstruction and reanimation after radical parotidectomy are limited and no consensus exists on the best practice. This study retrospectively reviewed all patients having undergone radical parotidectomy and immediate facial nerve reconstruction with a free, non-vascularized nerve graft at the Helsinki University Hospital, Helsinki, Finland during the years 1990-2010. There were 31 patients (18 male; mean age = 54.7 years; range = 30-82) and 23 of them had a sufficient follow-up time. Facial nerve function recovery was seen in 18 (78%) of the 23 patients with a minimum of 2-year follow-up and adequate reporting available. Only slight facial movement was observed in five (22%), moderate or good movement in nine (39%), and excellent movement in four (17%) patients. Twenty-two (74%) patients received post-operative radiotherapy and 16 (70%) of them had some recovery of facial nerve function. Nineteen (61%) patients needed secondary static reanimation of the face.

Small vestibular schwannomas presenting with facial nerve palsy.

PubMed

Espahbodi, Mana; Carlson, Matthew L; Fang, Te-Yung; Thompson, Reid C; Haynes, David S

2014-06-01

To describe the surgical management and convalescence of two patients presenting with severe facial nerve weakness associated with small intracanalicular vestibular schwannomas (VS). Retrospective review. Two adult female patients presenting with audiovestibular symptoms and subacute facial nerve paralysis (House-Brackmann Grade IV and V). In both cases, post-contrast T1-weighted magnetic resonance imaging revealed an enhancing lesion within the internal auditory canal without lateral extension beyond the fundus. Translabyrinthine exploration demonstrated vestibular nerve origin of tumor, extrinsic to the facial nerve, and frozen section pathology confirmed schwannoma. Gross total tumor resection with VIIth cranial nerve preservation and decompression of the labyrinthine segment of the facial nerve was performed. Both patients recovered full motor function between 6 and 8 months after surgery. Although rare, small VS may cause severe facial neuropathy, mimicking the presentation of facial nerve schwannomas and other less common pathologies. In the absence of labyrinthine extension on MRI, surgical exploration is the only reliable means of establishing a diagnosis. In the case of confirmed VS, early gross total resection with facial nerve preservation and labyrinthine segment decompression may afford full motor recovery-an outcome that cannot be achieved with facial nerve grafting.

Neuro-ophthalmological approach to facial nerve palsy.

PubMed

Portelinha, Joana; Passarinho, Maria Picoto; Costa, João Marques

2015-01-01

Facial nerve palsy is associated with significant morbidity and can have different etiologies. The most common causes are Bell's palsy, Ramsay-Hunt syndrome and trauma, including surgical trauma. Incidence varies between 17 and 35 cases per 100,000. Initial evaluation should include accurate clinical history, followed by a comprehensive investigation of the head and neck, including ophthalmological, otological, oral and neurological examination, to exclude secondary causes. Routine laboratory testing and diagnostic imaging is not indicated in patients with new-onset Bell's palsy, but should be performed in patients with risk factors, atypical cases or in any case without resolution within 4 months. Many factors are involved in determining the appropriate treatment of these patients: the underlying cause, expected duration of nerve dysfunction, anatomical manifestations, severity of symptoms and objective clinical findings. Systemic steroids should be offered to patients with new-onset Bell's palsy to increase the chance of facial nerve recovery and reduce synkinesis. Ophthalmologists play a pivotal role in the multidisciplinary team involved in the evaluation and rehabilitation of these patients. In the acute phase, the main priority should be to ensure adequate corneal protection. Treatment depends on the degree of nerve lesion and on the risk of the corneal damage based on the amount of lagophthalmos, the quality of Bell's phenomenon, the presence or absence of corneal sensitivity and the degree of lid retraction. The main therapy is intensive lubrication. Other treatments include: taping the eyelid overnight, botulinum toxin injection, tarsorrhaphy, eyelid weight implants, scleral contact lenses and palpebral spring. Once the cornea is protected, longer term planning for eyelid and facial rehabilitation may take place. Spontaneous complete recovery of Bell's palsy occurs in up to 70% of cases. Long-term complications include aberrant regeneration with

Neuro-ophthalmological approach to facial nerve palsy

PubMed Central

Portelinha, Joana; Passarinho, Maria Picoto; Costa, João Marques

2014-01-01

Facial nerve palsy is associated with significant morbidity and can have different etiologies. The most common causes are Bell’s palsy, Ramsay–Hunt syndrome and trauma, including surgical trauma. Incidence varies between 17 and 35 cases per 100,000. Initial evaluation should include accurate clinical history, followed by a comprehensive investigation of the head and neck, including ophthalmological, otological, oral and neurological examination, to exclude secondary causes. Routine laboratory testing and diagnostic imaging is not indicated in patients with new-onset Bell’s palsy, but should be performed in patients with risk factors, atypical cases or in any case without resolution within 4 months. Many factors are involved in determining the appropriate treatment of these patients: the underlying cause, expected duration of nerve dysfunction, anatomical manifestations, severity of symptoms and objective clinical findings. Systemic steroids should be offered to patients with new-onset Bell’s palsy to increase the chance of facial nerve recovery and reduce synkinesis. Ophthalmologists play a pivotal role in the multidisciplinary team involved in the evaluation and rehabilitation of these patients. In the acute phase, the main priority should be to ensure adequate corneal protection. Treatment depends on the degree of nerve lesion and on the risk of the corneal damage based on the amount of lagophthalmos, the quality of Bell’s phenomenon, the presence or absence of corneal sensitivity and the degree of lid retraction. The main therapy is intensive lubrication. Other treatments include: taping the eyelid overnight, botulinum toxin injection, tarsorrhaphy, eyelid weight implants, scleral contact lenses and palpebral spring. Once the cornea is protected, longer term planning for eyelid and facial rehabilitation may take place. Spontaneous complete recovery of Bell’s palsy occurs in up to 70% of cases. Long-term complications include aberrant regeneration

Facial nerve mapping and monitoring in lymphatic malformation surgery.

PubMed

Chiara, Jospeh; Kinney, Greg; Slimp, Jefferson; Lee, Gi Soo; Oliaei, Sepehr; Perkins, Jonathan A

2009-10-01

Establish the efficacy of preoperative facial nerve mapping and continuous intraoperative EMG monitoring in protecting the facial nerve during resection of cervicofacial lymphatic malformations. Retrospective study in which patients were clinically followed for at least 6 months postoperatively, and long-term outcome was evaluated. Patient demographics, lesion characteristics (i.e., size, stage, location) were recorded. Operative notes revealed surgical techniques, findings, and complications. Preoperative, short-/long-term postoperative facial nerve function was standardized using the House-Brackmann Classification. Mapping was done prior to incision by percutaneously stimulating the facial nerve and its branches and recording the motor responses. Intraoperative monitoring and mapping were accomplished using a four-channel, free-running EMG. Neurophysiologists continuously monitored EMG responses and blindly analyzed intraoperative findings and final EMG interpretations for abnormalities. Seven patients collectively underwent 8 lymphatic malformation surgeries. Median age was 30 months (2-105 months). Lymphatic malformation diagnosis was recorded in 6/8 surgeries. Facial nerve function was House-Brackmann grade I in 8/8 cases preoperatively. Facial nerve was abnormally elongated in 1/8 cases. EMG monitoring recorded abnormal activity in 4/8 cases--two suggesting facial nerve irritation, and two with possible facial nerve damage. Transient or long-term facial nerve paresis occurred in 1/8 cases (House-Brackmann grade II). Preoperative facial nerve mapping combined with continuous intraoperative EMG and mapping is a successful method of identifying the facial nerve course and protecting it from injury during resection of cervicofacial lymphatic malformations involving the facial nerve.

Facial neuropathy with imaging enhancement of the facial nerve: a case report

PubMed Central

Mumtaz, Sehreen; Jensen, Matthew B

2014-01-01

A young women developed unilateral facial neuropathy 2 weeks after a motor vehicle collision involving fractures of the skull and mandible. MRI showed contrast enhancement of the facial nerve. We review the literature describing facial neuropathy after trauma and facial nerve enhancement patterns with different causes of facial neuropathy. PMID:25574155

Facial nerve paralysis secondary to occult malignant neoplasms.

PubMed

Boahene, Derek O; Olsen, Kerry D; Driscoll, Colin; Lewis, Jean E; McDonald, Thomas J

2004-04-01

This study reviewed patients with unilateral facial paralysis and normal clinical and imaging findings who underwent diagnostic facial nerve exploration. Study design and setting Fifteen patients with facial paralysis and normal findings were seen in the Mayo Clinic Department of Otorhinolaryngology. Eleven patients were misdiagnosed as having Bell palsy or idiopathic paralysis. Progressive facial paralysis with sequential involvement of adjacent facial nerve branches occurred in all 15 patients. Seven patients had a history of regional skin squamous cell carcinoma, 13 patients had surgical exploration to rule out a neoplastic process, and 2 patients had negative exploration. At last follow-up, 5 patients were alive. Patients with facial paralysis and normal clinical and imaging findings should be considered for facial nerve exploration when the patient has a history of pain or regional skin cancer, involvement of other cranial nerves, and prolonged facial paralysis. Occult malignancy of the facial nerve may cause unilateral facial paralysis in patients with normal clinical and imaging findings.

Hypoglossal-facial nerve reconstruction using a Y-tube-conduit reduces aberrant synkinetic movements of the orbicularis oculi and vibrissal muscles in rats.

PubMed

Kaya, Yasemin; Ozsoy, Umut; Turhan, Murat; Angelov, Doychin N; Sarikcioglu, Levent

2014-01-01

The facial nerve is the most frequently damaged nerve in head and neck trauma. Patients undergoing facial nerve reconstruction often complain about disturbing abnormal synkinetic movements of the facial muscles (mass movements, synkinesis) which are thought to result from misguided collateral branching of regenerating motor axons and reinnervation of inappropriate muscles. Here, we examined whether use of an aorta Y-tube conduit during reconstructive surgery after facial nerve injury reduces synkinesis of orbicularis oris (blink reflex) and vibrissal (whisking) musculature. The abdominal aorta plus its bifurcation was harvested (N = 12) for Y-tube conduits. Animal groups comprised intact animals (Group 1), those receiving hypoglossal-facial nerve end-to-end coaptation alone (HFA; Group 2), and those receiving hypoglossal-facial nerve reconstruction using a Y-tube (HFA-Y-tube, Group 3). Videotape motion analysis at 4 months showed that HFA-Y-tube group showed a reduced synkinesis of eyelid and whisker movements compared to HFA alone.

Hypoglossal-Facial Nerve Reconstruction Using a Y-Tube-Conduit Reduces Aberrant Synkinetic Movements of the Orbicularis Oculi and Vibrissal Muscles in Rats

PubMed Central

Kaya, Yasemin; Ozsoy, Umut; Turhan, Murat; Angelov, Doychin N.; Sarikcioglu, Levent

2014-01-01

The facial nerve is the most frequently damaged nerve in head and neck trauma. Patients undergoing facial nerve reconstruction often complain about disturbing abnormal synkinetic movements of the facial muscles (mass movements, synkinesis) which are thought to result from misguided collateral branching of regenerating motor axons and reinnervation of inappropriate muscles. Here, we examined whether use of an aorta Y-tube conduit during reconstructive surgery after facial nerve injury reduces synkinesis of orbicularis oris (blink reflex) and vibrissal (whisking) musculature. The abdominal aorta plus its bifurcation was harvested (N = 12) for Y-tube conduits. Animal groups comprised intact animals (Group 1), those receiving hypoglossal-facial nerve end-to-end coaptation alone (HFA; Group 2), and those receiving hypoglossal-facial nerve reconstruction using a Y-tube (HFA-Y-tube, Group 3). Videotape motion analysis at 4 months showed that HFA-Y-tube group showed a reduced synkinesis of eyelid and whisker movements compared to HFA alone. PMID:25574468

Facial nerve paralysis in children

PubMed Central

Ciorba, Andrea; Corazzi, Virginia; Conz, Veronica; Bianchini, Chiara; Aimoni, Claudia

2015-01-01

Facial nerve palsy is a condition with several implications, particularly when occurring in childhood. It represents a serious clinical problem as it causes significant concerns in doctors because of its etiology, its treatment options and its outcome, as well as in little patients and their parents, because of functional and aesthetic outcomes. There are several described causes of facial nerve paralysis in children, as it can be congenital (due to delivery traumas and genetic or malformative diseases) or acquired (due to infective, inflammatory, neoplastic, traumatic or iatrogenic causes). Nonetheless, in approximately 40%-75% of the cases, the cause of unilateral facial paralysis still remains idiopathic. A careful diagnostic workout and differential diagnosis are particularly recommended in case of pediatric facial nerve palsy, in order to establish the most appropriate treatment, as the therapeutic approach differs in relation to the etiology. PMID:26677445

Nerve growth factor reduces apoptotic cell death in rat facial motor neurons after facial nerve injury.

PubMed

Hui, Lian; Yuan, Jing; Ren, Zhong; Jiang, Xuejun

2015-01-01

To assess the effects of nerve growth factor (NGF) on motor neurons after induction of a facial nerve lesion, and to compare the effects of different routes of NGF injection on motor neuron survival. This study was carried out in the Department of Otolaryngology Head & Neck Surgery, China Medical University, Liaoning, China from October 2012 to March 2013. Male Wistar rats (n = 65) were randomly assigned into 4 groups: A) healthy controls; B) facial nerve lesion model + normal saline injection; C) facial nerve lesion model + NGF injection through the stylomastoid foramen; D) facial nerve lesion model + intraperitoneal injection of NGF. Apoptotic cell death was detected using the terminal deoxynucleotidyl transferase dUTP nick end-labeling assay. Expression of caspase-3 and p53 up-regulated modulator of apoptosis (PUMA) was determined by immunohistochemistry. Injection of NGF significantly reduced cell apoptosis, and also greatly decreased caspase-3 and PUMA expression in injured motor neurons. Group C exhibited better efficacy for preventing cellular apoptosis and decreasing caspase-3 and PUMA expression compared with group D (p<0.05). Our findings suggest that injections of NGF may prevent apoptosis of motor neurons by decreasing caspase-3 and PUMA expression after facial nerve injury in rats. The NGF injected through the stylomastoid foramen demonstrated better protective efficacy than when injected intraperitoneally.

Overlapping Mechanisms of Peripheral Nerve Regeneration and Angiogenesis Following Sciatic Nerve Transection

PubMed Central

Wang, Hongkui; Zhu, Hui; Guo, Qi; Qian, Tianmei; Zhang, Ping; Li, Shiying; Xue, Chengbin; Gu, Xiaosong

2017-01-01

Peripheral nervous system owns the ability of self-regeneration, mainly in its regenerative microenvironment including vascular network reconstruction. More recently, more attentions have been given to the close relationship between tissue regeneration and angiogenesis. To explore the overlap of molecular mechanisms and key regulation molecules between peripheral nerve regeneration and angiogenesis post peripheral nerve injury, integrative and bioinformatic analysis was carried out for microarray data of proximal stumps after sciatic nerve transection in SD rats. Nerve regeneration and angiogenesis were activated at 1 day immediately after sciatic nerve transection simultaneously. The more obvious changes of transcription regulators and canonical pathways suggested a phase transition between 1 and 4 days of both nerve regeneration and angiogenesis after sciatic nerve transection. Furthermore, 16 differentially expressed genes participated in significant biological processes of both nerve regeneration and angiogenesis, a few of which were validated by qPCR and immunofluorescent staining. It was demonstrated that STAT3, EPHB3, and Cdc42 co-expressed in Schwann cells and vascular endothelial cells to play a key role in regulation of nerve regeneration and angiogenesis simultaneously response to sciatic nerve transection. We provide a framework for understanding biological processes and precise molecular correlations between peripheral nerve regeneration and angiogenesis after peripheral nerve transection. Our work serves as an experimental basis and a valuable resource to further understand molecular mechanisms that define nerve injury-induced micro-environmental variation for achieving desired peripheral nerve regeneration. PMID:29085283

Overlapping Mechanisms of Peripheral Nerve Regeneration and Angiogenesis Following Sciatic Nerve Transection.

PubMed

Wang, Hongkui; Zhu, Hui; Guo, Qi; Qian, Tianmei; Zhang, Ping; Li, Shiying; Xue, Chengbin; Gu, Xiaosong

2017-01-01

Peripheral nervous system owns the ability of self-regeneration, mainly in its regenerative microenvironment including vascular network reconstruction. More recently, more attentions have been given to the close relationship between tissue regeneration and angiogenesis. To explore the overlap of molecular mechanisms and key regulation molecules between peripheral nerve regeneration and angiogenesis post peripheral nerve injury, integrative and bioinformatic analysis was carried out for microarray data of proximal stumps after sciatic nerve transection in SD rats. Nerve regeneration and angiogenesis were activated at 1 day immediately after sciatic nerve transection simultaneously. The more obvious changes of transcription regulators and canonical pathways suggested a phase transition between 1 and 4 days of both nerve regeneration and angiogenesis after sciatic nerve transection. Furthermore, 16 differentially expressed genes participated in significant biological processes of both nerve regeneration and angiogenesis, a few of which were validated by qPCR and immunofluorescent staining. It was demonstrated that STAT3, EPHB3, and Cdc42 co-expressed in Schwann cells and vascular endothelial cells to play a key role in regulation of nerve regeneration and angiogenesis simultaneously response to sciatic nerve transection. We provide a framework for understanding biological processes and precise molecular correlations between peripheral nerve regeneration and angiogenesis after peripheral nerve transection. Our work serves as an experimental basis and a valuable resource to further understand molecular mechanisms that define nerve injury-induced micro-environmental variation for achieving desired peripheral nerve regeneration.

Diagnosis and surgical outcomes of intraparotid facial nerve schwannoma showing normal facial nerve function.

PubMed

Lee, D W; Byeon, H K; Chung, H P; Choi, E C; Kim, S-H; Park, Y M

2013-07-01

The findings of intraparotid facial nerve schwannoma (FNS) using preoperative diagnostic tools, including ultrasonography (US)-guided fine needle aspiration biopsy, computed tomography (CT) scan, and magnetic resonance imaging (MRI), were analyzed to determine if there are any useful findings that might suggest the presence of a lesion. Treatment guidelines are suggested. The medical records of 15 patients who were diagnosed with an intraparotid FNS were retrospectively analyzed. US and CT scans provide clinicians with only limited information; gadolinium enhanced T1-weighted images from MRI provide more specific findings. Tumors could be removed successfully with surgical exploration, preserving facial nerve function at the same time. Gadolinium-enhanced T1-weighted MRI showed more characteristic findings for the diagnosis of intraparotid FNS. Intraparotid FNS without facial palsy can be diagnosed with MRI preoperatively, and surgical exploration is a suitable treatment modality which can remove the tumor and preserve facial nerve function. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Nerve crush but not displacement-induced stretch of the intra-arachnoidal facial nerve promotes facial palsy after cerebellopontine angle surgery.

PubMed

Bendella, Habib; Brackmann, Derald E; Goldbrunner, Roland; Angelov, Doychin N

2016-10-01

Little is known about the reasons for occurrence of facial nerve palsy after removal of cerebellopontine angle tumors. Since the intra-arachnoidal portion of the facial nerve is considered to be so vulnerable that even the slightest tension or pinch may result in ruptured axons, we tested whether a graded stretch or controlled crush would affect the postoperative motor performance of the facial (vibrissal) muscle in rats. Thirty Wistar rats, divided into five groups (one with intact controls and four with facial nerve lesions), were used. Under inhalation anesthesia, the occipital squama was opened, the cerebellum gently retracted to the left, and the intra-arachnoidal segment of the right facial nerve exposed. A mechanical displacement of the brainstem with 1 or 3 mm toward the midline or an electromagnet-controlled crush of the facial nerve with a tweezers at a closure velocity of 50 and 100 mm/s was applied. On the next day, whisking motor performance was determined by video-based motion analysis. Even the larger (with 3 mm) mechanical displacement of the brainstem had no harmful effect: The amplitude of the vibrissal whisks was in the normal range of 50°-60°. On the other hand, even the light nerve crush (50 mm/s) injured the facial nerve and resulted in paralyzed vibrissal muscles (amplitude of 10°-15°). We conclude that, contrary to the generally acknowledged assumptions, it is the nerve crush but not the displacement-induced stretching of the intra-arachnoidal facial trunk that promotes facial palsy after cerebellopontine angle surgery in rats.

Tissue-engineered spiral nerve guidance conduit for peripheral nerve regeneration.

PubMed

Chang, Wei; Shah, Munish B; Lee, Paul; Yu, Xiaojun

2018-06-01

Recently in peripheral nerve regeneration, preclinical studies have shown that the use of nerve guidance conduits (NGCs) with multiple longitudinally channels and intra-luminal topography enhance the functional outcomes when bridging a nerve gap caused by traumatic injury. These features not only provide guidance cues for regenerating nerve, but also become the essential approaches for developing a novel NGC. In this study, a novel spiral NGC with aligned nanofibers and wrapped with an outer nanofibrous tube was first developed and investigated. Using the common rat sciatic 10-mm nerve defect model, the in vivo study showed that a novel spiral NGC (with and without inner nanofibers) increased the successful rate of nerve regeneration after 6 weeks recovery. Substantial improvements in nerve regeneration were achieved by combining the spiral NGC with inner nanofibers and outer nanofibrous tube, based on the results of walking track analysis, electrophysiology, nerve histological assessment, and gastrocnemius muscle measurement. This demonstrated that the novel spiral NGC with inner aligned nanofibers and wrapped with an outer nanofibrous tube provided a better environment for peripheral nerve regeneration than standard tubular NGCs. Results from this study will benefit for future NGC design to optimize tissue-engineering strategies for peripheral nerve regeneration. We developed a novel spiral nerve guidance conduit (NGC) with coated aligned nanofibers. The spiral structure increases surface area by 4.5 fold relative to a tubular NGC. Furthermore, the aligned nanofibers was coated on the spiral walls, providing cues for guiding neurite extension. Finally, the outside of spiral NGC was wrapped with randomly nanofibers to enhance mechanical strength that can stabilize the spiral NGC. Our nerve histological data have shown that the spiral NGC had 50% more myelinated axons than a tubular structure for nerve regeneration across a 10 mm gap in a rat sciatic nerve

[Regional nerve block in facial surgery].

PubMed

Gramkow, Christina; Sørensen, Jesper

2008-02-11

Regional nerve blocking techniques offer a suitable alternative to local infiltration anaesthesia for facial soft tissue-surgery. Moreover, they present several advantages over general anaesthesia, including smoother recovery, fewer side effects, residual analgesia into the postoperative period, earlier discharge from the recovery room and reduced costs. The branches of the trigeminal nerve and the sensory nerves originating from the upper cervical plexus can be targeted at several anatomical locations. We summarize current knowledge on facial nerve block techniques and recommend ten nerve blocks providing efficient anaesthesia for the entire head and upper-neck region.

Efficacy of Laser Photobiomodulation on Morphological and Functional Repair of the Facial Nerve.

PubMed

Buchaim, Daniela Vieira; Andreo, Jesus Carlos; Ferreira Junior, Rui Seabra; Barraviera, Benedito; Rodrigues, Antonio de Castro; Macedo, Mariana de Cássia; Rosa Junior, Geraldo Marco; Shinohara, Andre Luis; Santos German, Iris Jasmin; Pomini, Karina Torres; Buchaim, Rogerio Leone

2017-08-01

Evaluate the efficacy of low-level laser therapy (LLLT) on qualitative, quantitative, and functional aspects in the facial nerve regeneration process. Forty-two male Wistar rats were used, randomly divided into a control group (CG; n = 10), in which the facial nerve without lesion was collected, and four experimental groups: (1) suture experimental group (SEG) and (2) fibrin experimental group (FEG), consisting of 16 animals in which the buccal branch of the facial nerve was sectioned on both sides of the face; an end-to-end epineural suture was performed on the right side, and a fibrin sealant was used on the left side for coaptation of the stumps; and (3) laser suture experimental group (LSEG) and (4) laser fibrin experimental group (LFEG), consisting of 16 animals that underwent the same surgical procedures as SEG and FEG with the addition of laser application at three different points along the surgical site (pulsed laser of 830 nm wavelength, optical output power of 30 mW, power density of 0.2586 W/cm 2 , energy density of 6.2 J/cm 2 , beam area of 0.116 cm 2 , exposure time of 24 sec per point, total energy per session of 2.16 J, and cumulative dose of 34.56 J). The animals were submitted to functional analysis (subjective observation of whisker movement) and the data obtained were compared using Fisher's exact test. Euthanasia was performed at 5 and 10 weeks postoperative. The total number and density of regenerated axons were analyzed using the unpaired t-test (p < 0.05). Laser therapy resulted in a significant increase in the number and density of regenerated axons. The LSEG and LFEG presented better scores in functional analysis in comparison with the SEG and FEG. LLLT enhanced axonal regeneration and accelerated functional recovery of the whiskers, and both repair techniques allowed the growth of axons.

Long-Term Facial Nerve Outcomes after Microsurgical Resection of Vestibular Schwannomas in Patients with Preoperative Facial Nerve Palsy.

PubMed

Mooney, Michael A; Hendricks, Benjamin; Sarris, Christina E; Spetzler, Robert F; Almefty, Kaith K; Porter, Randall W

2018-06-01

Objectives  This study aimed at evaluating facial nerve outcomes in vestibular schwannoma patients presenting with preoperative facial nerve palsy. Design  A retrospective review. Setting  Single-institution cohort. Participants  Overall, 368 consecutive patients underwent vestibular schwannoma resection. Patients with prior microsurgery or radiosurgery were excluded. Main Outcome Measures  Incidence, House-Brackmann grade. Results  Of 368 patients, 9 had confirmed preoperative facial nerve dysfunction not caused by prior treatment, for an estimated incidence of 2.4%. Seven of these nine patients had Koos grade 4 tumors. Mean tumor diameter was 3.0 cm (range: 2.1-4.4 cm), and seven of nine tumors were subtotally resected. All nine patients were followed up clinically for ≥ 6 months. Of the six patients with a preoperative House-Brackmann grade of II, two improved to grade I, three were stable, and one patient worsened to grade III. Of the three patients with grade III or worse, all remained stable at last follow-up. Conclusions  Preoperative facial nerve palsy is rare in patients with vestibular schwannoma; it tends to occur in patients with relatively large lesions. Detailed long-term outcomes of facial nerve function after microsurgical resection for these patients have not been reported previously. We followed nine patients and found that eight (89%) of the nine patients had either stable or improved facial nerve outcomes after treatment. Management strategies varied for these patients, including rates of subtotal versus gross-total resection and the use of stereotactic radiosurgery in patients with residual tumor. These results can be used to help counsel patients preoperatively on expected outcomes of facial nerve function after treatment.

Atf3 mutant mice show reduced axon regeneration and impaired regeneration-associated gene induction after peripheral nerve injury

PubMed Central

Gey, Manuel; Wanner, Renate; Schilling, Corinna; Pedro, Maria T.; Sinske, Daniela

2016-01-01

Axon injury in the peripheral nervous system (PNS) induces a regeneration-associated gene (RAG) response. Atf3 (activating transcription factor 3) is such a RAG and ATF3's transcriptional activity might induce ‘effector’ RAGs (e.g. small proline rich protein 1a (Sprr1a), Galanin (Gal), growth-associated protein 43 (Gap43)) facilitating peripheral axon regeneration. We provide a first analysis of Atf3 mouse mutants in peripheral nerve regeneration. In Atf3 mutant mice, facial nerve regeneration and neurite outgrowth of adult ATF3-deficient primary dorsal root ganglia neurons was decreased. Using genome-wide transcriptomics, we identified a neuropeptide-encoding RAG cluster (vasoactive intestinal peptide (Vip), Ngf, Grp, Gal, Pacap) regulated by ATF3. Exogenous administration of neuropeptides enhanced neurite growth of Atf3 mutant mice suggesting that these molecules might be effector RAGs of ATF3's pro-regenerative function. In addition to the induction of growth-promoting molecules, we present data that ATF3 suppresses growth-inhibiting molecules such as chemokine (C-C motif) ligand 2. In summary, we show a pro-regenerative ATF3 function during PNS nerve regeneration involving transcriptional activation of a neuropeptide-encoding RAG cluster. ATF3 is a general injury-inducible factor, therefore ATF3-mediated mechanisms identified herein might apply to other cell and injury types. PMID:27581653

Patterned substrates and methods for nerve regeneration

DOEpatents

Mallapragada, Surya K.; Heath, Carole; Shanks, Howard; Miller, Cheryl A.; Jeftinija, Srdija

2004-01-13

Micropatterned substrates and methods for fabrication of artificial nerve regeneration conduits and methods for regenerating nerves are provided. Guidance compounds or cells are seeded in grooves formed on the patterned substrate. The substrates may also be provided with electrodes to provide electrical guidance cues to the regenerating nerve. The micropatterned substrates give physical, chemical, cellular and/or electrical guidance cues to promote nerve regeneration at the cellular level.

Glucose transporters GLUT4 and GLUT8 are upregulated after facial nerve axotomy in adult mice.

PubMed

Gómez, Olga; Ballester-Lurbe, Begoña; Mesonero, José E; Terrado, José

2011-10-01

Peripheral nerve axotomy in adult mice elicits a complex response that includes increased glucose uptake in regenerating nerve cells. This work analyses the expression of the neuronal glucose transporters GLUT3, GLUT4 and GLUT8 in the facial nucleus of adult mice during the first days after facial nerve axotomy. Our results show that whereas GLUT3 levels do not vary, GLUT4 and GLUT8 immunoreactivity increases in the cell body of the injured motoneurons after the lesion. A sharp increase in GLUT4 immunoreactivity was detected 3 days after the nerve injury and levels remained high on Day 8, but to a lesser extent. GLUT8 also increased the levels but later than GLUT4, as they only rose on Day 8 post-lesion. These results indicate that glucose transport is activated in regenerating motoneurons and that GLUT4 plays a main role in this function. These results also suggest that metabolic defects involving impairment of glucose transporters may be principal components of the neurotoxic mechanisms leading to motoneuron death. © 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society of Great Britain and Ireland.

Hypoglossal-facial-jump-anastomosis without an interposition nerve graft.

PubMed

Beutner, Dirk; Luers, Jan C; Grosheva, Maria

2013-10-01

The hypoglossal-facial-anastomosis is the most often applied procedure for the reanimation of a long lasting peripheral facial nerve paralysis. The use of an interposition graft and its end-to-side anastomosis to the hypoglossal nerve allows the preservation of the tongue function and also requires two anastomosis sites and a free second donor nerve. We describe the modified technique of the hypoglossal-facial-jump-anastomosis without an interposition and present the first results. Retrospective case study. We performed the facial nerve reconstruction in five patients. The indication for the surgery was a long-standing facial paralysis with preserved portion distal to geniculate ganglion, absent voluntary activity in the needle facial electromyography, and an intact bilateral hypoglossal nerve. Following mastoidectomy, the facial nerve was mobilized in the fallopian canal down to its bifurcation in the parotid gland and cut in its tympanic portion distal to the lesion. Then, a tensionless end-to-side suture to the hypoglossal nerve was performed. The facial function was monitored up to 16 months postoperatively. The reconstruction technique succeeded in all patients: The facial function improved within the average time period of 10 months to the House-Brackmann score 3. This modified technique of the hypoglossal-facial reanimation is a valid method with good clinical results, especially in cases of a preserved intramastoidal facial nerve. Level 4. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Regenerating Fish Optic Nerves and a Regeneration-Like Response in Injured Optic Nerves of Adult Rabbits

NASA Astrophysics Data System (ADS)

Schwartz, M.; Belkin, M.; Harel, A.; Solomon, A.; Lavie, V.; Hadani, M.; Rachailovich, I.; Stein-Izsak, C.

1985-05-01

Regeneration of fish optic nerve (representing regenerative central nervous system) was accompanied by increased activity of regeneration-triggering factors produced by nonneuronal cells. A graft of regenerating fish optic nerve, or a ``wrap-around'' implant containing medium conditioned by it, induced a response associated with regeneration in injured optic nerves of adult rabbits (representing a nonregenerative central nervous system). This response was manifested by an increase of general protein synthesis and of selective polypeptides in the retinas and by the ability of the retina to sprout in culture.

[Anatomicopathological relation between facial nerve and large vestibular Schwannoma].

PubMed

Jiang, T; Yu, C; Guo, E; Guan, S; Yan, C

2001-05-10

To study the anatomicopathological relation between facial nerve and large vestibular schwannoma. Operation by suboccipital retrosigmoid sinus approach was performed on 40 cases with large vestibular schwannoma, During the operation, the anatomicopathological relation between the facial nerve and the vestibular schwannoma was observed directly. The facial nerve was found to be located ventrally (deep under the tumor), dorsally (over the tumor), at the upper pole of the tumor (near the tentorium cerebelli), at the lower pole of the tumor (near the rear group cranial nerves), or aberrant (unable to be identified because of infiltration of tumor). In 31 cases, mainly with parenchymatous tumor, the facial nerve was flat in shape. In 9 cases, mainly with cystic tumor, the facial nerve was bandlike. The facial nerve varies greatly in neuroanatomy among patients with large vestibular schwannoma. Strengthening of operative monitoring can increase the safety of operation.

Nerve Cross-Bridging to Enhance Nerve Regeneration in a Rat Model of Delayed Nerve Repair

PubMed Central

2015-01-01

There are currently no available options to promote nerve regeneration through chronically denervated distal nerve stumps. Here we used a rat model of delayed nerve repair asking of prior insertion of side-to-side cross-bridges between a donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) nerve stump ameliorates poor nerve regeneration. First, numbers of retrogradely-labelled TIB neurons that grew axons into the nerve stump within three months, increased with the size of the perineurial windows opened in the TIB and CP nerves. Equal numbers of donor TIB axons regenerated into CP stumps either side of the cross-bridges, not being affected by target neurotrophic effects, or by removing the perineurium to insert 5-9 cross-bridges. Second, CP nerve stumps were coapted three months after inserting 0-9 cross-bridges and the number of 1) CP neurons that regenerated their axons within three months or 2) CP motor nerves that reinnervated the extensor digitorum longus (EDL) muscle within five months was determined by counting and motor unit number estimation (MUNE), respectively. We found that three but not more cross-bridges promoted the regeneration of axons and reinnervation of EDL muscle by all the CP motoneurons as compared to only 33% regenerating their axons when no cross-bridges were inserted. The same 3-fold increase in sensory nerve regeneration was found. In conclusion, side-to-side cross-bridges ameliorate poor regeneration after delayed nerve repair possibly by sustaining the growth-permissive state of denervated nerve stumps. Such autografts may be used in human repair surgery to improve outcomes after unavoidable delays. PMID:26016986

Peripheral Nerve Regeneration Strategies: Electrically Stimulating Polymer Based Nerve Growth Conduits

PubMed Central

Anderson, Matthew; Shelke, Namdev B.; Manoukian, Ohan S.; Yu, Xiaojun; McCullough, Louise D.; Kumbar, Sangamesh G.

2017-01-01

Treatment of large peripheral nerve damages ranges from the use of an autologous nerve graft to a synthetic nerve growth conduit. Biological grafts, in spite of many merits, show several limitations in terms of availability and donor site morbidity, and outcomes are suboptimal due to fascicle mismatch, scarring, and fibrosis. Tissue engineered nerve graft substitutes utilize polymeric conduits in conjunction with cues both chemical and physical, cells alone and or in combination. The chemical and physical cues delivered through polymeric conduits play an important role and drive tissue regeneration. Electrical stimulation (ES) has been applied toward the repair and regeneration of various tissues such as muscle, tendon, nerve, and articular tissue both in laboratory and clinical settings. The underlying mechanisms that regulate cellular activities such as cell adhesion, proliferation, cell migration, protein production, and tissue regeneration following ES is not fully understood. Polymeric constructs that can carry the electrical stimulation along the length of the scaffold have been developed and characterized for possible nerve regeneration applications. We discuss the use of electrically conductive polymers and associated cell interaction, biocompatibility, tissue regeneration, and recent basic research for nerve regeneration. In conclusion, a multifunctional combinatorial device comprised of biomaterial, structural, functional, cellular, and molecular aspects may be the best way forward for effective peripheral nerve regeneration. PMID:27278739

Effect of postoperative brachytherapy and external beam radiotherapy on functional outcomes of immediate facial nerve repair after radical parotidectomy.

PubMed

Hontanilla, Bernardo; Qiu, Shan-Shan; Marré, Diego

2014-01-01

There is much controversy regarding the effect of radiotherapy on facial nerve regeneration. However, the effect of brachytherapy has not been studied. Fifty-three patients underwent total parotidectomy of which 13 were radical with immediate facial nerve repair with sural nerve grafts. Six patients (group 1) did not receive adjuvant treatment whereas 7 patients (group 2) received postoperative brachytherapy plus radiotherapy. Functional outcomes were compared using Facial Clima. Mean percentage of blink recovery was 92.6 ± 4.2 for group 1 and 90.7 ± 5.2 for group 2 (p = .37). Mean percentage of commissural excursion restoration was 78.1 ± 3.5 for group 1 and 74.9 ± 5.9 for group 2 (p = .17). Mean time from surgery to first movement was 5.7 ± 0.9 months for group 1 and 6.3 ± 0.5 months for group 2 (p = .15). Brachytherapy plus radiotherapy does not affect the functional outcomes of immediate facial nerve repair with nerve grafts. Copyright © 2013 Wiley Periodicals, Inc.

Magnetic resonance imaging of facial nerve schwannoma.

PubMed

Thompson, Andrew L; Aviv, Richard I; Chen, Joseph M; Nedzelski, Julian M; Yuen, Heng-Wai; Fox, Allan J; Bharatha, Aditya; Bartlett, Eric S; Symons, Sean P

2009-12-01

This study characterizes the magnetic resonance (MR) appearances of facial nerve schwannoma (FNS). We hypothesize that the extent of FNS demonstrated on MR will be greater compared to prior computed tomography studies, that geniculate involvement will be most common, and that cerebellar pontine angle (CPA) and internal auditory canal (IAC) involvement will more frequently result in sensorineural hearing loss (SNHL). Retrospective study. Clinical, pathologic, and enhanced MR imaging records of 30 patients with FNS were analyzed. Morphologic characteristics and extent of segmental facial nerve involvement were documented. Median age at initial imaging was 51 years (range, 28-76 years). Pathologic confirmation was obtained in 14 patients (47%), and the diagnosis reached in the remainder by identification of a mass, thickening, and enhancement along the course of the facial nerve. All 30 lesions involved two or more contiguous segments of the facial nerve, with 28 (93%) involving three or more segments. The median segments involved per lesion was 4, mean of 3.83. Geniculate involvement was most common, in 29 patients (97%). CPA (P = .001) and IAC (P = .02) involvement was significantly related to SNHL. Seventeen patients (57%) presented with facial nerve dysfunction, manifesting in 12 patients as facial nerve weakness or paralysis, and/or in eight with involuntary movements of the facial musculature. This study highlights the morphologic heterogeneity and typical multisegment involvement of FNS. Enhanced MR is the imaging modality of choice for FNS. The neuroradiologist must accurately diagnose and characterize this lesion, and thus facilitate optimal preoperative planning and counseling.

[Peripheral facial nerve lesion induced long-term dendritic retraction in pyramidal cortico-facial neurons].

PubMed

Urrego, Diana; Múnera, Alejandro; Troncoso, Julieta

2011-01-01

Little evidence is available concerning the morphological modifications of motor cortex neurons associated with peripheral nerve injuries, and the consequences of those injuries on post lesion functional recovery. Dendritic branching of cortico-facial neurons was characterized with respect to the effects of irreversible facial nerve injury. Twenty-four adult male rats were distributed into four groups: sham (no lesion surgery), and dendritic assessment at 1, 3 and 5 weeks post surgery. Eighteen lesion animals underwent surgical transection of the mandibular and buccal branches of the facial nerve. Dendritic branching was examined by contralateral primary motor cortex slices stained with the Golgi-Cox technique. Layer V pyramidal (cortico-facial) neurons from sham and injured animals were reconstructed and their dendritic branching was compared using Sholl analysis. Animals with facial nerve lesions displayed persistent vibrissal paralysis throughout the five week observation period. Compared with control animal neurons, cortico-facial pyramidal neurons of surgically injured animals displayed shrinkage of their dendritic branches at statistically significant levels. This shrinkage persisted for at least five weeks after facial nerve injury. Irreversible facial motoneuron axonal damage induced persistent dendritic arborization shrinkage in contralateral cortico-facial neurons. This morphological reorganization may be the physiological basis of functional sequelae observed in peripheral facial palsy patients.

Large Intratemporal Facial Nerve Schwannoma without Facial Palsy: Surgical Strategy of Tumor Removal and Functional Reconstruction.

PubMed

Yetiser, Sertac

2018-06-08

 Three patients with large intratemporal facial schwannomas underwent tumor removal and facial nerve reconstruction with hypoglossal anastomosis. The surgical strategy for the cases was tailored to the location of the mass and its extension along the facial nerve.  To provide data on the different clinical aspects of facial nerve schwannoma, the appropriate planning for management, and the predictive outcomes of facial function.  Three patients with facial schwannomas (two men and one woman, ages 45, 36, and 52 years, respectively) who presented to the clinic between 2009 and 2015 were reviewed. They all had hearing loss but normal facial function. All patients were operated on with radical tumor removal via mastoidectomy and subtotal petrosectomy and simultaneous cranial nerve (CN) 7- CN 12 anastomosis.  Multiple segments of the facial nerve were involved ranging in size from 3 to 7 cm. In the follow-up period of 9 to 24 months, there was no tumor recurrence. Facial function was scored House-Brackmann grades II and III, but two patients are still in the process of functional recovery.  Conservative treatment with sparing of the nerve is considered in patients with small tumors. Excision of a large facial schwannoma with immediate hypoglossal nerve grafting as a primary procedure can provide satisfactory facial nerve function. One of the disadvantages of performing anastomosis is that there is not enough neural tissue just before the bifurcation of the main stump to provide neural suturing without tension because middle fossa extension of the facial schwannoma frequently involves the main facial nerve at the stylomastoid foramen. Reanimation should be processed with extensive backward mobilization of the hypoglossal nerve. Georg Thieme Verlag KG Stuttgart · New York.

Facial reanimation with gracilis muscle transfer neurotized to cross-facial nerve graft versus masseteric nerve: a comparative study using the FACIAL CLIMA evaluating system.

PubMed

Hontanilla, Bernardo; Marre, Diego; Cabello, Alvaro

2013-06-01

Longstanding unilateral facial paralysis is best addressed with microneurovascular muscle transplantation. Neurotization can be obtained from the cross-facial or the masseter nerve. The authors present a quantitative comparison of both procedures using the FACIAL CLIMA system. Forty-seven patients with complete unilateral facial paralysis underwent reanimation with a free gracilis transplant neurotized to either a cross-facial nerve graft (group I, n=20) or to the ipsilateral masseteric nerve (group II, n=27). Commissural displacement and commissural contraction velocity were measured using the FACIAL CLIMA system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using the independent samples t test. Mean percentage of recovery of both parameters were compared between the groups using the independent samples t test. Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I (p=0.001 and p=0.014, respectively) but not in group II. Intergroup comparisons showed that both commissural displacement and commissural contraction velocity were higher in group II, with significant differences for commissural displacement (p=0.048). Mean percentage of recovery of both parameters was higher in group II, with significant differences for commissural displacement (p=0.042). Free gracilis muscle transfer neurotized by the masseteric nerve is a reliable technique for reanimation of longstanding facial paralysis. Compared with cross-facial nerve graft neurotization, this technique provides better symmetry and a higher degree of recovery. Therapeutic, III.

Nerves Regulate Cardiomyocyte Proliferation and Heart Regeneration.

PubMed

Mahmoud, Ahmed I; O'Meara, Caitlin C; Gemberling, Matthew; Zhao, Long; Bryant, Donald M; Zheng, Ruimao; Gannon, Joseph B; Cai, Lei; Choi, Wen-Yee; Egnaczyk, Gregory F; Burns, Caroline E; Burns, C Geoffrey; MacRae, Calum A; Poss, Kenneth D; Lee, Richard T

2015-08-24

Some organisms, such as adult zebrafish and newborn mice, have the capacity to regenerate heart tissue following injury. Unraveling the mechanisms of heart regeneration is fundamental to understanding why regeneration fails in adult humans. Numerous studies have revealed that nerves are crucial for organ regeneration, thus we aimed to determine whether nerves guide heart regeneration. Here, we show using transgenic zebrafish that inhibition of cardiac innervation leads to reduction of myocyte proliferation following injury. Specifically, pharmacological inhibition of cholinergic nerve function reduces cardiomyocyte proliferation in the injured hearts of both zebrafish and neonatal mice. Direct mechanical denervation impairs heart regeneration in neonatal mice, which was rescued by the administration of neuregulin 1 (NRG1) and nerve growth factor (NGF) recombinant proteins. Transcriptional analysis of mechanically denervated hearts revealed a blunted inflammatory and immune response following injury. These findings demonstrate that nerve function is required for both zebrafish and mouse heart regeneration. Copyright © 2015 Elsevier Inc. All rights reserved.

Transtympanic Facial Nerve Paralysis: A Review of the Literature

PubMed Central

Schaefer, Nathan; O’Donohue, Peter; French, Heath; Griffin, Aaron; Gochee, Peter

2015-01-01

Summary: Facial nerve paralysis because of penetrating trauma through the external auditory canal is extremely rare, with a paucity of published literature. The objective of this study is to review the literature on transtympanic facial nerve paralysis and increase physician awareness of this uncommon injury through discussion of its clinical presentation, management and prognosis. We also aim to improve patient outcomes in those that have sustained this type of injury by suggesting an optimal management plan. In this case report, we present the case of a 46-year-old white woman who sustained a unilateral facial nerve paresis because of a garfish penetrating her tympanic membrane and causing direct damage to the tympanic portion of her facial nerve. On follow-up after 12 months, her facial nerve function has largely returned to normal. Transtympanic facial nerve paralysis is a rare injury but can have a favorable prognosis if managed effectively. PMID:26090278

Facial Nerve Trauma: Evaluation and Considerations in Management

PubMed Central

Gordin, Eli; Lee, Thomas S.; Ducic, Yadranko; Arnaoutakis, Demetri

2014-01-01

The management of facial paralysis continues to evolve. Understanding the facial nerve anatomy and the different methods of evaluating the degree of facial nerve injury are crucial for successful management. When the facial nerve is transected, direct coaptation leads to the best outcome, followed by interpositional nerve grafting. In cases where motor end plates are still intact but a primary repair or graft is not feasible, a nerve transfer should be employed. When complete muscle atrophy has occurred, regional muscle transfer or free flap reconstruction is an option. When dynamic reanimation cannot be undertaken, static procedures offer some benefit. Adjunctive tools such as botulinum toxin injection and biofeedback can be helpful. Several new treatment modalities lie on the horizon which hold potential to alter the current treatment algorithm. PMID:25709748

Management of synkinesis and asymmetry in facial nerve palsy: a review article.

PubMed

Pourmomeny, Abbas Ali; Asadi, Sahar

2014-10-01

The important sequelae of facial nerve palsy are synkinesis, asymmetry, hypertension and contracture; all of which have psychosocial effects on patients. Synkinesis due to mal regeneration causes involuntary movements during a voluntary movement. Previous studies have advocated treatment using physiotherapy modalities alone or with exercise therapy, but no consensus exists on the optimal approach. Thus, this review summarizes clinical controlled studies in the management of synkinesis and asymmetry in facial nerve palsy. Case-controlled clinical studies of patients at the acute stage of injury were selected for this review article. Data were obtained from English-language databases from 1980 until mid-2013. Among 124 articles initially captured, six randomized controlled trials involving 269 patients were identified with appropriate inclusion criteria. The results of all these studies emphasized the benefit of exercise therapy. Four studies considered electromyogram (EMG) biofeedback to be effective through neuromuscular re-education. Synkinesis and inconsistency of facial muscles could be treated with educational exercise therapy. EMG biofeedback is a suitable tool for this exercise therapy.

A System for Studying Facial Nerve Function in Rats through Simultaneous Bilateral Monitoring of Eyelid and Whisker Movements

PubMed Central

Heaton, James T.; Kowaleski, Jeffrey M.; Bermejo, Roberto; Zeigler, H. Philip; Ahlgren, David J.; Hadlock, Tessa A.

2008-01-01

The occurrence of inappropriate co-contraction of facially innervated muscles in humans (synkinesis) is a common sequela of facial nerve injury and recovery. We have developed a system for studying facial nerve function and synkinesis in restrained rats using non-contact opto-electronic techniques that enable simultaneous bilateral monitoring of eyelid and whisker movements. Whisking is monitored in high spatio-temporal resolution using laser micrometers, and eyelid movements are detected using infrared diode and phototransistor pairs that respond to the increased reflection when the eyelids cover the cornea. To validate the system, eight rats were tested with multiple five-minute sessions that included corneal air puffs to elicit blink and scented air flows to elicit robust whisking. Four rats then received unilateral facial nerve section and were tested at weeks 3–6. Whisking and eye blink behavior occurred both spontaneously and under stimulus control, with no detectable difference from published whisking data. Proximal facial nerve section caused an immediate ipsilateral loss of whisking and eye blink response, but some ocular closures emerged due to retractor bulbi muscle function. The independence observed between whisker and eyelid control indicates that this system may provide a powerful tool for identifying abnormal co-activation of facial zones resulting from aberrant axonal regeneration. PMID:18442856

Middle ear osteoma causing progressive facial nerve weakness: a case report.

PubMed

Curtis, Kate; Bance, Manohar; Carter, Michael; Hong, Paul

2014-09-18

Facial nerve weakness is most commonly due to Bell's palsy or cerebrovascular accidents. Rarely, middle ear tumor presents with facial nerve dysfunction. We report a very unusual case of middle ear osteoma in a 49-year-old Caucasian woman causing progressive facial nerve deficit. A subtle middle ear lesion was observed on otoscopy and computed tomographic images demonstrated an osseous middle ear tumor. Complete surgical excision resulted in the partial recovery of facial nerve function. Facial nerve dysfunction is rarely caused by middle ear tumors. The weakness is typically due to a compressive effect on the middle ear portion of the facial nerve. Early recognition is crucial since removal of these lesions may lead to the recuperation of facial nerve function.

Hypoglossal-facial nerve "side"-to-side neurorrhaphy for facial paralysis resulting from closed temporal bone fractures.

PubMed

Su, Diya; Li, Dezhi; Wang, Shiwei; Qiao, Hui; Li, Ping; Wang, Binbin; Wan, Hong; Schumacher, Michael; Liu, Song

2018-06-06

Closed temporal bone fractures due to cranial trauma often result in facial nerve injury, frequently inducing incomplete facial paralysis. Conventional hypoglossal-facial nerve end-to-end neurorrhaphy may not be suitable for these injuries because sacrifice of the lesioned facial nerve for neurorrhaphy destroys the remnant axons and/or potential spontaneous innervation. we modified the classical method by hypoglossal-facial nerve "side"-to-side neurorrhaphy using an interpositional predegenerated nerve graft to treat these injuries. Five patients who experienced facial paralysis resulting from closed temporal bone fractures due to cranial trauma were treated with the "side"-to-side neurorrhaphy. An additional 4 patients did not receive the neurorrhaphy and served as controls. Before treatment, all patients had suffered House-Brackmann (H-B) grade V or VI facial paralysis for a mean of 5 months. During the 12-30 months of follow-up period, no further detectable deficits were observed, but an improvement in facial nerve function was evidenced over time in the 5 neurorrhaphy-treated patients. At the end of follow-up, the improved facial function reached H-B grade II in 3, grade III in 1 and grade IV in 1 of the 5 patients, consistent with the electrophysiological examinations. In the control group, two patients showed slightly spontaneous innervation with facial function improved from H-B grade VI to V, and the other patients remained unchanged at H-B grade V or VI. We concluded that the hypoglossal-facial nerve "side"-to-side neurorrhaphy can preserve the injured facial nerve and is suitable for treating significant incomplete facial paralysis resulting from closed temporal bone fractures, providing an evident beneficial effect. Moreover, this treatment may be performed earlier after the onset of facial paralysis in order to reduce the unfavorable changes to the injured facial nerve and atrophy of its target muscles due to long-term denervation and allow axonal

Delayed presentation of traumatic facial nerve (CN VII) paralysis.

PubMed

Napoli, Anthony M; Panagos, Peter

2005-11-01

Facial nerve paralysis (Cranial Nerve VII, CN VII) can be a disfiguring disorder with profound impact upon the patient. The etiology of facial nerve paralysis may be congenital, iatrogenic, or result from neoplasm, infection, trauma, or toxic exposure. In the emergency department, the most common cause of unilateral facial paralysis is Bell's palsy, also known as idiopathic facial paralysis (IFP). We report a case of delayed presentation of unilateral facial nerve paralysis 3 days after sustaining a traumatic head injury. Re-evaluation and imaging of this patient revealed a full facial paralysis and temporal bone fracture extending into the facial canal. Because cranial nerve injuries occur in approximately 5-10% of head-injured patients, a good history and physical examination is important to differentiate IFP from another etiology. Newer generation high-resolution computed tomography (CT) scans are commonly demonstrating these fractures. An understanding of this complication, appropriate patient follow-up, and early involvement of the Otolaryngologist is important in management of these patients. The mechanism as well as the timing of facial nerve paralysis will determine the proper evaluation, consultation, and management for the patient. Patients with total or immediate paralysis as well as those with poorly prognostic audiogram results are good candidates for surgical repair.

Facial nerve conduction after sclerotherapy in children with facial lymphatic malformations: report of two cases.

PubMed

Lin, Pei-Jung; Guo, Yuh-Cherng; Lin, Jan-You; Chang, Yu-Tang

2007-04-01

Surgical excision is thought to be the standard treatment of choice for lymphatic malformations. However, when the lesions are limited to the face only, surgical scar and facial nerve injury may impair cosmetics and facial expression. Sclerotherapy, an injection of a sclerosing agent directly through the skin into a lesion, is an alternative method. By evaluating facial nerve conduction, we observed the long-term effect of facial lymphatic malformations after intralesional injection of OK-432 and correlated the findings with anatomic outcomes. One 12-year-old boy with a lesion over the right-side preauricular area adjacent to the main trunk of facial nerve and the other 5-year-old boy with a lesion in the left-sided cheek involving the buccinator muscle were enrolled. The follow-up data of more than one year, including clinical appearance, computed tomography (CT) scan and facial nerve evaluation were collected. The facial nerve conduction study was normal in both cases. Blink reflex in both children revealed normal results as well. Complete resolution was noted on outward appearance and CT scan. The neurophysiologic data were compatible with good anatomic and functional outcomes. Our report suggests that the inflammatory reaction of OK-432 did not interfere with adjacent facial nerve conduction.

Electrophysiology of Cranial Nerve Testing: Trigeminal and Facial Nerves.

PubMed

Muzyka, Iryna M; Estephan, Bachir

2018-01-01

The clinical examination of the trigeminal and facial nerves provides significant diagnostic value, especially in the localization of lesions in disorders affecting the central and/or peripheral nervous system. The electrodiagnostic evaluation of these nerves and their pathways adds further accuracy and reliability to the diagnostic investigation and the localization process, especially when different testing methods are combined based on the clinical presentation and the electrophysiological findings. The diagnostic uniqueness of the trigeminal and facial nerves is their connectivity and their coparticipation in reflexes commonly used in clinical practice, namely the blink and corneal reflexes. The other reflexes used in the diagnostic process and lesion localization are very nerve specific and add more diagnostic yield to the workup of certain disorders of the nervous system. This article provides a review of commonly used electrodiagnostic studies and techniques in the evaluation and lesion localization of cranial nerves V and VII.

Facial nerve palsy associated with a cystic lesion of the temporal bone.

PubMed

Kim, Na Hyun; Shin, Seung-Ho

2014-03-01

Facial nerve palsy results in the loss of facial expression and is most commonly caused by a benign, self-limiting inflammatory condition known as Bell palsy. However, there are other conditions that may cause facial paralysis, such as neoplastic conditions of the facial nerve, traumatic nerve injury, and temporal bone lesions. We present a case of facial nerve palsy concurrent with a benign cystic lesion of the temporal bone, adjacent to the tympanic segment of the facial nerve. The patient's symptoms subsided after facial nerve decompression via a transmastoid approach.

Preoperative Identification of Facial Nerve in Vestibular Schwannomas Surgery Using Diffusion Tensor Tractography

PubMed Central

Choi, Kyung-Sik; Kim, Min-Su; Kwon, Hyeok-Gyu; Jang, Sung-Ho

2014-01-01

Objective Facial nerve palsy is a common complication of treatment for vestibular schwannoma (VS), so preserving facial nerve function is important. The preoperative visualization of the course of facial nerve in relation to VS could help prevent injury to the nerve during the surgery. In this study, we evaluate the accuracy of diffusion tensor tractography (DTT) for preoperative identification of facial nerve. Methods We prospectively collected data from 11 patients with VS, who underwent preoperative DTT for facial nerve. Imaging results were correlated with intraoperative findings. Postoperative DTT was performed at postoperative 3 month. Facial nerve function was clinically evaluated according to the House-Brackmann (HB) facial nerve grading system. Results Facial nerve courses on preoperative tractography were entirely correlated with intraoperative findings in all patients. Facial nerve was located on the anterior of the tumor surface in 5 cases, on anteroinferior in 3 cases, on anterosuperior in 2 cases, and on posteroinferior in 1 case. In postoperative facial nerve tractography, preservation of facial nerve was confirmed in all patients. No patient had severe facial paralysis at postoperative one year. Conclusion This study shows that DTT for preoperative identification of facial nerve in VS surgery could be a very accurate and useful radiological method and could help to improve facial nerve preservation. PMID:25289119

Contemporary solutions for the treatment of facial nerve paralysis.

PubMed

Garcia, Ryan M; Hadlock, Tessa A; Klebuc, Michael J; Simpson, Roger L; Zenn, Michael R; Marcus, Jeffrey R

2015-06-01

After reviewing this article, the participant should be able to: 1. Understand the most modern indications and technique for neurotization, including masseter-to-facial nerve transfer (fifth-to-seventh cranial nerve transfer). 2. Contrast the advantages and limitations associated with contiguous muscle transfers and free-muscle transfers for facial reanimation. 3. Understand the indications for a two-stage and one-stage free gracilis muscle transfer for facial reanimation. 4. Apply nonsurgical adjuvant treatments for acute facial nerve paralysis. Facial expression is a complex neuromotor and psychomotor process that is disrupted in patients with facial paralysis breaking the link between emotion and physical expression. Contemporary reconstructive options are being implemented in patients with facial paralysis. While static procedures provide facial symmetry at rest, true 'facial reanimation' requires restoration of facial movement. Contemporary treatment options include neurotization procedures (a new motor nerve is used to restore innervation to a viable muscle), contiguous regional muscle transfer (most commonly temporalis muscle transfer), microsurgical free muscle transfer, and nonsurgical adjuvants used to balance facial symmetry. Each approach has advantages and disadvantages along with ongoing controversies and should be individualized for each patient. Treatments for patients with facial paralysis continue to evolve in order to restore the complex psychomotor process of facial expression.

Collision tumor of the facial nerve: a synchronous seventh nerve schwannoma and neurofibroma.

PubMed

Gross, Brian C; Carlson, Matthew L; Driscoll, Colin L; Moore, Eric J

2012-10-01

To report a novel case of a collision tumor involving an intraparotid neurofibroma and a mastoid segment facial nerve schwannoma. Clinical capsule report. Tertiary academic referral center. A 29-year-old woman with a 2-year history of an asymptomatic enlarging left infraauricular mass and normal FN function presented to a tertiary care referral center. Computed tomography and magnetic resonance imaging demonstrated a cystic lesion in the deep portion of the parotid gland extending into the stylomastoid foramen. The patient underwent superficial parotidectomy, and a cystic parotid mass was found to be intrinsic to the intraparotid facial nerve. A portion of the mass was biopsied, and intraoperative frozen section pathology was consistent with a neurofibroma. A mastoidectomy with FN decompression was then performed until a normal-appearing segment was identified just proximal to the second genu. After biopsy, proximal facial nerve stimulation failed to elicit evoked motor potentials, and en bloc resection was performed. Final pathology demonstrated a schwannoma involving the mastoid segment and a neurofibroma involving the proximal intraparotid facial nerve. We report the first case of a facial nerve collision tumor involving an intraparotid neurofibroma and a mastoid segment facial nerve schwannoma. Benign FN sheath tumors of the parotid gland are rare but should be considered in the differential diagnosis of a parotid mass.

Miconazole enhances nerve regeneration and functional recovery after sciatic nerve crush injury.

PubMed

Lin, Tao; Qiu, Shuai; Yan, Liwei; Zhu, Shuang; Zheng, Canbin; Zhu, Qingtang; Liu, Xiaolin

2018-05-01

Improving axonal outgrowth and remyelination is crucial for peripheral nerve regeneration. Miconazole appears to enhance remyelination in the central nervous system. In this study we assess the effect of miconazole on axonal regeneration using a sciatic nerve crush injury model in rats. Fifty Sprague-Dawley rats were divided into control and miconazole groups. Nerve regeneration and myelination were determined using histological and electrophysiological assessment. Evaluation of sensory and motor recovery was performed using the pinprick assay and sciatic functional index. The Cell Counting Kit-8 assay and Western blotting were used to assess the proliferation and neurotrophic expression of RSC 96 Schwann cells. Miconazole promoted axonal regrowth, increased myelinated nerve fibers, improved sensory recovery and walking behavior, enhanced stimulated amplitude and nerve conduction velocity, and elevated proliferation and neurotrophic expression of RSC 96 Schwann cells. Miconazole was beneficial for nerve regeneration and functional recovery after peripheral nerve injury. Muscle Nerve 57: 821-828, 2018. © 2017 Wiley Periodicals, Inc.

Intraparotid Neurofibroma of the Facial Nerve: A Case Report.

PubMed

Nofal, Ahmed-Abdel-Fattah; El-Anwar, Mohammad-Waheed

2016-07-01

Intraparotid neurofibromas of the facial nerve are extremely rare and mostly associated with neurofibromatosis type 1 (NF1). This is a case of a healthy 40-year-old man, which underwent surgery for a preoperatively diagnosed benign parotid gland lesion. After identification of the facial nerve main trunk, a single large mass (6 x 3 cm) incorporating the upper nerve division was observed. The nerve portion involved in the mass could not be dissected and was inevitably sacrificed with immediate neuroraphy of the upper division of the facial nerve with 6/0 prolene. The final histopathology revealed the presence of a neurofibroma. Complete left side facial nerve paralysis was observed immediately postoperatively but the function of the lower half was returned within 4 months and the upper half was returned after 1 year. Currently, after 3 years of follow up, there are no signs of recurrence and normal facial nerve function is observed. Neurofibroma should be considered as the diagnosis in a patient demonstrating a parotid mass. In cases where it is diagnosed intraoperatively, excision of part of the nerve with the mass will be inevitable though it can be successfully repaired by end to end anastomosis.

Aberrant regeneration of the third cranial nerve.

PubMed

Shrestha, U D; Adhikari, S

2012-01-01

Aberrant regeneration of the third cranial nerve is most commonly due to its damage by trauma. A ten-month old child presented with the history of a fall from a four-storey building. She developed traumatic third nerve palsy and eventually the clinical features of aberrant regeneration of the third cranial nerve. The adduction of the eye improved over time. She was advised for patching for the strabismic amblyopia as well. Traumatic third nerve palsy may result in aberrant regeneration of the third cranial nerve. In younger patients, motility of the eye in different gazes may improve over time. © NEPjOPH.

Intra-temporal facial nerve centerline segmentation for navigated temporal bone surgery

NASA Astrophysics Data System (ADS)

Voormolen, Eduard H. J.; van Stralen, Marijn; Woerdeman, Peter A.; Pluim, Josien P. W.; Noordmans, Herke J.; Regli, Luca; Berkelbach van der Sprenkel, Jan W.; Viergever, Max A.

2011-03-01

Approaches through the temporal bone require surgeons to drill away bone to expose a target skull base lesion while evading vital structures contained within it, such as the sigmoid sinus, jugular bulb, and facial nerve. We hypothesize that an augmented neuronavigation system that continuously calculates the distance to these structures and warns if the surgeon drills too close, will aid in making safe surgical approaches. Contemporary image guidance systems are lacking an automated method to segment the inhomogeneous and complexly curved facial nerve. Therefore, we developed a segmentation method to delineate the intra-temporal facial nerve centerline from clinically available temporal bone CT images semi-automatically. Our method requires the user to provide the start- and end-point of the facial nerve in a patient's CT scan, after which it iteratively matches an active appearance model based on the shape and texture of forty facial nerves. Its performance was evaluated on 20 patients by comparison to our gold standard: manually segmented facial nerve centerlines. Our segmentation method delineates facial nerve centerlines with a maximum error along its whole trajectory of 0.40+/-0.20 mm (mean+/-standard deviation). These results demonstrate that our model-based segmentation method can robustly segment facial nerve centerlines. Next, we can investigate whether integration of this automated facial nerve delineation with a distance calculating neuronavigation interface results in a system that can adequately warn surgeons during temporal bone drilling, and effectively diminishes risks of iatrogenic facial nerve palsy.

Habilitation of facial nerve dysfunction after resection of a vestibular schwannoma.

PubMed

Rudman, Kelli L; Rhee, John S

2012-04-01

Facial nerve dysfunction after resection of a vestibular schwannoma is one of the most common indications for facial nerve habilitation. This article presents an overview of common and emerging management options for facial habilitation following resection of a vestibular schwannoma. Immediate and delayed nerve repair options, as well as adjunctive surgical, medical, and physical therapies for facial nerve dysfunction, are discussed. Two algorithms are provided as guides for the assessment and treatment of facial nerve paralysis after resection of vestibular schwannoma. Copyright © 2012 Elsevier Inc. All rights reserved.

Facial Nerve Schwannoma: A Case Report, Radiological Features and Literature Review.

PubMed

Pilloni, Giulia; Mico, Barbara Massa; Altieri, Roberto; Zenga, Francesco; Ducati, Alessandro; Garbossa, Diego; Tartara, Fulvio

2017-12-22

Facial nerve schwannoma localized in the middle fossa is a rare lesion. We report a case of a facial nerve schwannoma in a 30-year-old male presenting with facial nerve palsy. Magnetic resonance imaging (MRI) showed a 3 cm diameter tumor of the right middle fossa. The tumor was removed using a sub-temporal approach. Intraoperative monitoring allowed for identification of the facial nerve, so it was not damaged during the surgical excision. Neurological clinical examination at discharge demonstrated moderate facial nerve improvement (Grade III House-Brackmann).

Comparison of hemihypoglossal nerve versus masseteric nerve transpositions in the rehabilitation of short-term facial paralysis using the Facial Clima evaluating system.

PubMed

Hontanilla, Bernardo; Marré, Diego

2012-11-01

Masseteric and hypoglossal nerve transfers are reliable alternatives for reanimating short-term facial paralysis. To date, few studies exist in the literature comparing these techniques. This work presents a quantitative comparison of masseter-facial transposition versus hemihypoglossal facial transposition with a nerve graft using the Facial Clima system. Forty-six patients with complete unilateral facial paralysis underwent reanimation with either hemihypoglossal transposition with a nerve graft (group I, n = 25) or direct masseteric-facial coaptation (group II, n = 21). Commissural displacement and commissural contraction velocity were measured using the Facial Clima system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using a paired sample t test. Then, mean percentages of recovery of both parameters were compared between the groups using an independent sample t test. Onset of movement was also compared between the groups. Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I but not in group II. Mean percentage of recovery of both parameters did not differ between the groups. Patients in group II showed a significantly faster onset of movement compared with those in group I (62 ± 4.6 days versus 136 ± 7.4 days, p = 0.013). Reanimation of short-term facial paralysis can be satisfactorily addressed by means of either hemihypoglossal transposition with a nerve graft or direct masseteric-facial coaptation. However, with the latter, better symmetry and a faster onset of movement are observed. In addition, masseteric nerve transfer avoids morbidity from nerve graft harvesting. Therapeutic, III.

The facial nerve: anatomy and associated disorders for oral health professionals.

PubMed

Takezawa, Kojiro; Townsend, Grant; Ghabriel, Mounir

2018-04-01

The facial nerve, the seventh cranial nerve, is of great clinical significance to oral health professionals. Most published literature either addresses the central connections of the nerve or its peripheral distribution but few integrate both of these components and also highlight the main disorders affecting the nerve that have clinical implications in dentistry. The aim of the current study is to provide a comprehensive description of the facial nerve. Multiple aspects of the facial nerve are discussed and integrated, including its neuroanatomy, functional anatomy, gross anatomy, clinical problems that may involve the nerve, and the use of detailed anatomical knowledge in the diagnosis of the site of facial nerve lesion in clinical neurology. Examples are provided of disorders that can affect the facial nerve during its intra-cranial, intra-temporal and extra-cranial pathways, and key aspects of clinical management are discussed. The current study is complemented by original detailed dissections and sketches that highlight key anatomical features and emphasise the extent and nature of anatomical variations displayed by the facial nerve.

Anatomical variations of the facial nerve in first branchial cleft anomalies.

PubMed

Solares, C Arturo; Chan, James; Koltai, Peter J

2003-03-01

To review our experience with branchial cleft anomalies, with special attention to their subtypes and anatomical relationship to the facial nerve. Case series. Tertiary care center. Ten patients who underwent resection for anomalies of the first branchial cleft, with at least 1 year of follow-up, were included in the study. The data from all cases were collected in a prospective fashion, including immediate postoperative diagrams. Complete resection of the branchial cleft anomaly was performed in all cases. Wide exposure of the facial nerve was achieved using a modified Blair incision and superficial parotidectomy. Facial nerve monitoring was used in every case. The primary outcome measurements were facial nerve function and incidence of recurrence after resection of the branchial cleft anomaly. Ten patients, 6 females and 4 males,with a mean age of 9 years at presentation, were treated by the senior author (P.J.K.) between 1989 and 2001. The lesions were characterized as sinus tracts (n = 5), fistulous tracts (n = 3), and cysts (n = 2). Seven lesions were medial to the facial nerve, 2 were lateral to the facial nerve, and 1 was between branches of the facial nerve. There were no complications related to facial nerve paresis or paralysis, and none of the patients has had a recurrence. The successful treatment of branchial cleft anomalies requires a complete resection. A safe complete resection requires a full exposure of the facial nerve, as the lesions can be variably associated with the nerve.

Clinical outcome of continuous facial nerve monitoring during primary parotidectomy.

PubMed

Terrell, J E; Kileny, P R; Yian, C; Esclamado, R M; Bradford, C R; Pillsbury, M S; Wolf, G T

1997-10-01

To assess whether continuous facial nerve monitoring during parotidectomy is associated with a lower incidence of facial nerve paresis or paralysis compared with parotidectomy without monitoring and to assess the cost of such monitoring. A retrospective analysis of outcomes for patients who underwent parotidectomy with or without continuous facial nerve monitoring. University medical center. Fifty-six patients undergoing parotidectomy in whom continuous electromyographic monitoring was used and 61 patients in whom it was not used. (1) The incidence of early and persistent facial nerve paresis or paralysis and (2) the cost associated with facial nerve monitoring. Early, unintentional facial weakness was significantly lower in the group monitored by electromyograpy (43.6%) than in the unmonitored group (62.3%) (P=.04). In the subgroup of patients without comorbid conditions or surgeries, early weakness in the monitored group (33.3%) remained statistically lower than the rate of early weakness in the unmonitored group (57.5%) (P=.03). There was no statistical difference in the final facial nerve function or incidence of permanent nerve injury between the groups or subgroups. After multivariate analysis, nonmonitored status (odds ratio [OR], 3.22), advancing age (OR, 1.47 per 10 years), and longer operative times (OR, 1.3 per hour) were the only significant independent predictive variables significantly associated with early postoperative facial weakness. The incremental cost of facial nerve monitoring was $379. The results suggest that continuous electromyographic monitoring of facial muscle during primary parotidectomy reduces the incidence of short-term postoperative facial paresis. Advantages and disadvantages of this technique need to be considered together with the additional costs in deciding whether routine use of continuous monitoring is a useful, cost-effective adjunct to parotid surgery.

The Trigeminal (V) and Facial (VII) Cranial Nerves

PubMed Central

Sanders, Richard D.

2010-01-01

There are close functional and anatomical relationships between cranial nerves V and VII in both their sensory and motor divisions. Sensation on the face is innervated by the trigeminal nerves (V) as are the muscles of mastication, but the muscles of facial expression are innervated mainly by the facial nerve (VII) as is the sensation of taste. This article briefly reviews the anatomy of these cranial nerves, disorders of these nerves that are of particular importance to psychiatry, and some considerations for differential diagnosis. PMID:20386632

Effect of rocuronium on the level and mode of pre-synaptic acetylcholine release by facial and somatic nerves, and changes following facial nerve injury in rabbits.

PubMed

Tan, Jinghua; Xu, Jing; Xing, Yian; Chen, Lianhua; Li, Shitong

2015-01-01

Muscles innervated by the facial nerve show differential sensitivities to muscle relaxants than muscles innervated by somatic nerves. The evoked electromyography (EEMG) response is also proportionally reduced after facial nerve injury. This forms the theoretical basis for proper utilization of muscle relaxants to balance EEMG monitoring and immobility under general anesthesia. (1) To observe the relationships between the level and mode of acetylcholine (ACh) release and the duration of facial nerve injury, and the influence of rocuronium in an in vitro rabbit model. (2) To explore the pre-synaptic mechanisms of discrepant responses to a muscle relaxant. Quantal and non-quantal ACh release were measured by using intracellular microelectrode recording in the orbicularis oris 1 to 42 days after graded facial nerve injury and in the gastrocnemius with/without rocuronium. Quantal ACh release was significantly decreased by rocuronium in the orbicularis oris and gastrocnemius, but significantly more so in gastrocnemius. Quantal release was reduced after facial nerve injury, which was significantly correlated with the severity of nerve injury in the absence but not in the presence of rocuronium. Non-quantal ACh release was reduced after facial nerve injury, with many relationships observed depending on the extent of the injury. The extent of inhibition of non-quantal release by rocuronium correlated with the grade of facial nerve injury. These findings may explain why EEMG amplitude might be diminished after acute facial nerve injury but relatively preserved after chronic injury and differential responses in sensitivity to rocuronium.

Effect of rocuronium on the level and mode of pre-synaptic acetylcholine release by facial and somatic nerves, and changes following facial nerve injury in rabbits

PubMed Central

Tan, Jinghua; Xu, Jing; Xing, Yian; Chen, Lianhua; Li, Shitong

2015-01-01

Muscles innervated by the facial nerve show differential sensitivities to muscle relaxants than muscles innervated by somatic nerves. The evoked electromyography (EEMG) response is also proportionally reduced after facial nerve injury. This forms the theoretical basis for proper utilization of muscle relaxants to balance EEMG monitoring and immobility under general anesthesia. (1) To observe the relationships between the level and mode of acetylcholine (ACh) release and the duration of facial nerve injury, and the influence of rocuronium in an in vitro rabbit model. (2) To explore the pre-synaptic mechanisms of discrepant responses to a muscle relaxant. Quantal and non-quantal ACh release were measured by using intracellular microelectrode recording in the orbicularis oris 1 to 42 days after graded facial nerve injury and in the gastrocnemius with/without rocuronium. Quantal ACh release was significantly decreased by rocuronium in the orbicularis oris and gastrocnemius, but significantly more so in gastrocnemius. Quantal release was reduced after facial nerve injury, which was significantly correlated with the severity of nerve injury in the absence but not in the presence of rocuronium. Non-quantal ACh release was reduced after facial nerve injury, with many relationships observed depending on the extent of the injury. The extent of inhibition of non-quantal release by rocuronium correlated with the grade of facial nerve injury. These findings may explain why EEMG amplitude might be diminished after acute facial nerve injury but relatively preserved after chronic injury and differential responses in sensitivity to rocuronium. PMID:25973033

Acellular Nerve Allografts in Peripheral Nerve Regeneration: A Comparative Study

PubMed Central

Moore, Amy M.; MacEwan, Matthew; Santosa, Katherine B.; Chenard, Kristofer E.; Ray, Wilson Z.; Hunter, Daniel A.; Mackinnon, Susan E.; Johnson, Philip J.

2011-01-01

Background Processed nerve allografts offer a promising alternative to nerve autografts in the surgical management of peripheral nerve injuries where short deficits exist. Methods Three established models of acellular nerve allograft (cold-preserved, detergent-processed, and AxoGen® -processed nerve allografts) were compared to nerve isografts and silicone nerve guidance conduits in a 14 mm rat sciatic nerve defect. Results All acellular nerve grafts were superior to silicone nerve conduits in support of nerve regeneration. Detergent-processed allografts were similar to isografts at 6 weeks post-operatively, while AxoGen®-processed and cold-preserved allografts supported significantly fewer regenerating nerve fibers. Measurement of muscle force confirmed that detergent-processed allografts promoted isograft-equivalent levels of motor recovery 16 weeks post-operatively. All acellular allografts promoted greater amounts of motor recovery compared to silicone conduits. Conclusions These findings provide evidence that differential processing for removal of cellular constituents in preparing acellular nerve allografts affects recovery in vivo. PMID:21660979

[Blood-nerve barrier and peripheral nerve regeneration].

PubMed

Kanda, Takashi

2013-01-01

Blood-nerve barrier (BNB) restricts the movement of soluble mediators and leukocytes from the blood contents to the peripheral nervous system (PNS) parenchyma and thus maintains the endoneurial homeostasis. However, it interferes the supply of various neurotrophic factors from the blood constituents and stops the drainage of toxic substances out of the PNS parenchyma, resulting in the inhibition of peripheral nerve regeneration. If the manipulation of BNB function is possible, regeneration of peripheral nerve may be facilitated via the alteration of peripheral nerve microenvironment and ample supply of neurotrophic substances. A possible method to manipulate the BNB for therapeutic purposes is to modify the endothelial function using siRNAs, oligonucleotides and virus vectors. Another possible method is to modify BNB pericytes: small hydrophobic substances that can reach the pericyte membrane through the endothelial monolayer and strengthen the pericytic activity, including the release of various cytokines/chemokines that influence endothelial function, may also be useful as drug candidates to control the BNB function.

Delayed facial nerve decompression for Bell's palsy.

PubMed

Kim, Sang Hoon; Jung, Junyang; Lee, Jong Ha; Byun, Jae Yong; Park, Moon Suh; Yeo, Seung Geun

2016-07-01

Incomplete recovery of facial motor function continues to be long-term sequelae in some patients with Bell's palsy. The purpose of this study was to investigate the efficacy of transmastoid facial nerve decompression after steroid and antiviral treatment in patients with late stage Bell's palsy. Twelve patients underwent surgical decompression for Bell's palsy 21-70 days after onset, whereas 22 patients were followed up after steroid and antiviral therapy without decompression. Surgical criteria included greater than 90 % degeneration on electroneuronography and no voluntary electromyography potentials. This study was a retrospective study of electrodiagnostic data and medical chart review between 2006 and 2013. Recovery from facial palsy was assessed using the House-Brackmann grading system. Final recovery rate did not differ significantly in the two groups; however, all patients in the decompression group recovered to at least House-Brackmann grade III at final follow-up. Although postoperative hearing threshold was increased in both groups, there was no significant between group difference in hearing threshold. Transmastoid decompression of the facial nerve in patients with severe late stage Bell's palsy at risk for a poor facial nerve outcome reduced severe complications of facial palsy with minimal morbidity.

Transient delayed facial nerve palsy after inferior alveolar nerve block anesthesia.

PubMed

Tzermpos, Fotios H; Cocos, Alina; Kleftogiannis, Matthaios; Zarakas, Marissa; Iatrou, Ioannis

2012-01-01

Facial nerve palsy, as a complication of an inferior alveolar nerve block anesthesia, is a rarely reported incident. Based on the time elapsed, from the moment of the injection to the onset of the symptoms, the paralysis could be either immediate or delayed. The purpose of this article is to report a case of delayed facial palsy as a result of inferior alveolar nerve block, which occurred 24 hours after the anesthetic administration and subsided in about 8 weeks. The pathogenesis, treatment, and results of an 8-week follow-up for a 20-year-old patient referred to a private maxillofacial clinic are presented and discussed. The patient's previous medical history was unremarkable. On clinical examination the patient exhibited generalized weakness of the left side of her face with a flat and expressionless appearance, and she was unable to close her left eye. One day before the onset of the symptoms, the patient had visited her dentist for a routine restorative procedure on the lower left first molar and an inferior alveolar block anesthesia was administered. The patient's medical history, clinical appearance, and complete examinations led to the diagnosis of delayed facial nerve palsy. Although neurologic occurrences are rare, dentists should keep in mind that certain dental procedures, such as inferior alveolar block anesthesia, could initiate facial nerve palsy. Attention should be paid during the administration of the anesthetic solution.

[Clinical experience in facial nerve tumors: a review of 27 cases].

PubMed

Zhang, Fan; Wang, Yucheng; Dai, Chunfu; Chi, Fanglu; Zhou, Liang; Chen, Bing; Li, Huawei

2010-01-01

To analyze the clinical manifestations and the diagnosis of the facial nerve tumor according to the clinical information, and evaluate the different surgical approaches depending on tumor location. Twenty-seven cases of facial nerve tumors with general clinical informations available from 1999.9 to 2006.12 in the Shanghai EENT Hospital were reviewed retrospectively. Twenty (74.1%) schwannomas, 4 (14.8%) neurofibromas ,and 3 (11.1%) hemangiomas were identified with histopathology postoperatively. During the course of the disease, 23 patients (85.2%) suffered facial paralysis, both hearing loss and tinnitus affected 11 (40.7%) cases, 5 (18.5%) manifested infra-auricular mass and the others showed some of otalgia or vertigo or ear fullness or facial numbness/twitches. CT or/and MRI results in 24 cases indicated that the tumors originated from the facial nerve. Intra-operative findings showed that 24 (88.9%) cases involved no less than 2 segments of the facial nerve, of these 24 cases 87.5% (21/24) involved the mastoid portion, 70.8% (17/24) involved the tympanic portion, 62.5% (15/24) involved the geniculate ganglion, only 4.2% (1/24) involved the internal acoustic canal (IAC), and 3 cases (11.1%) had only one segments involved. In all of these 27 cases, the tumors were completely excised, of which 13 were resected followed by an immediate facial nerve reconstruction, including 11 sural nerve cable graft, 1 facial nerve end-to-end anastomosis and 1 hypoglossal-facial nerve end-to-end anastomosis. Tumors were removed with preservation of facial nerve continuity in 2 cases. Facial nerve tumor is a rare and benign lesion, and has numerous clinical manifestations. CT and MRI can help surgeons to make a right diagnosis preoperatively. When and how to give the patients an operation depends on the patients individually.

3D printing strategies for peripheral nerve regeneration.

PubMed

Petcu, Eugen B; Midha, Rajiv; McColl, Erin; Popa-Wagner, Aurel; Chirila, Traian V; Dalton, Paul D

2018-03-23

After many decades of biomaterials research for peripheral nerve regeneration, a clinical product (the nerve guide), is emerging as a proven alternative for relatively short injury gaps. This review identifies aspects where 3D printing can assist in improving long-distance nerve guide regeneration strategies. These include (1) 3D printing of the customizable nerve guides, (2) fabrication of scaffolds that fill nerve guides, (3) 3D bioprinting of cells within a matrix/bioink into the nerve guide lumen and the (4) establishment of growth factor gradients along the length a nerve guide. The improving resolution of 3D printing technologies will be an important factor for peripheral nerve regeneration, as fascicular-like guiding structures provide one path to improved nerve guidance. The capability of 3D printing to manufacture complex structures from patient data based on existing medical imaging technologies is an exciting aspect that could eventually be applied to treating peripheral nerve injury. Ultimately, the goal of 3D printing in peripheral nerve regeneration is the automated fabrication, potentially customized for the patient, of structures within the nerve guide that significantly outperform the nerve autograft over large gap injuries.

Sensation, mechanoreceptor, and nerve fiber function after nerve regeneration.

PubMed

Krarup, Christian; Rosén, Birgitta; Boeckstyns, Michel; Ibsen Sørensen, Allan; Lundborg, Göran; Moldovan, Mihai; Archibald, Simon J

2017-12-01

Sensation is essential for recovery after peripheral nerve injury. However, the relationship between sensory modalities and function of regenerated fibers is uncertain. We have investigated the relationships between touch threshold, tactile gnosis, and mechanoreceptor and sensory fiber function after nerve regeneration. Twenty-one median or ulnar nerve lesions were repaired by a collagen nerve conduit or direct suture. Quantitative sensory hand function and sensory conduction studies by near-nerve technique, including tactile stimulation of mechanoreceptors, were followed for 2 years, and results were compared to noninjured hands. At both repair methods, touch thresholds at the finger tips recovered to 81 ± 3% and tactile gnosis only to 20 ± 4% (p < 0.001) of control. The sensory nerve action potentials (SNAPs) remained dispersed and areas recovered to 23 ± 2% and the amplitudes only to 7 ± 1% (P < 0.001). The areas of SNAPs after tactile stimulation recovered to 61 ± 11% and remained slowed. Touch sensation correlated with SNAP areas (p < 0.005) and was negatively related to the prolongation of tactile latencies (p < 0.01); tactile gnosis was not related to electrophysiological parameters. The recovered function of regenerated peripheral nerve fibers and reinnervated mechanoreceptors may differentially influence recovery of sensory modalities. Touch was affected by the number and function of regenerated fibers and mechanoreceptors. In contrast, tactile gnosis depends on the input and plasticity of the central nervous system (CNS), which may explain the absence of a direct relation between electrophysiological parameters and poor recovery. Dispersed maturation of sensory nerve fibers with desynchronized inputs to the CNS also contributes to the poor recovery of tactile gnosis. Ann Neurol 2017. Ann Neurol 2017;82:940-950. © 2017 American Neurological Association.

Comparison of trophic factors' expression between paralyzed and recovering muscles after facial nerve injury. A quantitative analysis in time course.

PubMed

Grosheva, Maria; Nohroudi, Klaus; Schwarz, Alisa; Rink, Svenja; Bendella, Habib; Sarikcioglu, Levent; Klimaschewski, Lars; Gordon, Tessa; Angelov, Doychin N

2016-05-01

After peripheral nerve injury, recovery of motor performance negatively correlates with the poly-innervation of neuromuscular junctions (NMJ) due to excessive sprouting of the terminal Schwann cells. Denervated muscles produce short-range diffusible sprouting stimuli, of which some are neurotrophic factors. Based on recent data that vibrissal whisking is restored perfectly during facial nerve regeneration in blind rats from the Sprague Dawley (SD)/RCS strain, we compared the expression of brain derived neurotrophic factor (BDNF), fibroblast growth factor-2 (FGF2), insulin growth factors 1 and 2 (IGF1, IGF2) and nerve growth factor (NGF) between SD/RCS and SD-rats with normal vision but poor recovery of whisking function after facial nerve injury. To establish which trophic factors might be responsible for proper NMJ-reinnervation, the transected facial nerve was surgically repaired (facial-facial anastomosis, FFA) for subsequent analysis of mRNA and proteins expressed in the levator labii superioris muscle. A complicated time course of expression included (1) a late rise in BDNF protein that followed earlier elevated gene expression, (2) an early increase in FGF2 and IGF2 protein after 2 days with sustained gene expression, (3) reduced IGF1 protein at 28 days coincident with decline of raised mRNA levels to baseline, and (4) reduced NGF protein between 2 and 14 days with maintained gene expression found in blind rats but not the rats with normal vision. These findings suggest that recovery of motor function after peripheral nerve injury is due, at least in part, to a complex regulation of lesion-associated neurotrophic factors and cytokines in denervated muscles. The increase of FGF-2 protein and concomittant decrease of NGF (with no significant changes in BDNF or IGF levels) during the first week following FFA in SD/RCS blind rats possibly prevents the distal branching of regenerating axons resulting in reduced poly-innervation of motor endplates. Copyright �

Extracranial Facial Nerve Schwannoma Treated by Hypo-fractionated CyberKnife Radiosurgery.

PubMed

Sasaki, Ayaka; Miyazaki, Shinichiro; Hori, Tomokatsu

2016-09-21

Facial nerve schwannoma is a rare intracranial tumor. Treatment for this benign tumor has been controversial. Here, we report a case of extracranial facial nerve schwannoma treated successfully by hypo-fractionated CyberKnife (Accuray, Sunnyvale, CA) radiosurgery and discuss the efficacy of this treatment. A 34-year-old female noticed a swelling in her right mastoid process. The lesion enlarged over a seven-month period, and she experienced facial spasm on the right side. She was diagnosed with a facial schwannoma via a magnetic resonance imaging (MRI) scan of the head and neck and was told to wait until the facial nerve palsy subsides. She was referred to our hospital for radiation therapy. We planned a fractionated CyberKnife radiosurgery for three consecutive days. After CyberKnife radiosurgery, the mass in the right parotid gradually decreased in size, and the facial nerve palsy disappeared. At her eight-month follow-up, her facial spasm had completely disappeared. There has been no recurrence and the facial nerve function has been normal. We successfully demonstrated the efficacy of CyberKnife radiosurgery as an alternative treatment that also preserves neurofunction for facial nerve schwannomas.

The new heterologous fibrin sealant in combination with low-level laser therapy (LLLT) in the repair of the buccal branch of the facial nerve.

PubMed

Buchaim, Daniela Vieira; Rodrigues, Antonio de Castro; Buchaim, Rogerio Leone; Barraviera, Benedito; Junior, Rui Seabra Ferreira; Junior, Geraldo Marco Rosa; Bueno, Cleuber Rodrigo de Souza; Roque, Domingos Donizeti; Dias, Daniel Ventura; Dare, Leticia Rossi; Andreo, Jesus Carlos

2016-07-01

This study aimed to evaluate the effects of low-level laser therapy (LLLT) in the repair of the buccal branch of the facial nerve with two surgical techniques: end-to-end epineural suture and coaptation with heterologous fibrin sealant. Forty-two male Wistar rats were randomly divided into five groups: control group (CG) in which the buccal branch of the facial nerve was collected without injury; (2) experimental group with suture (EGS) and experimental group with fibrin (EGF): The buccal branch of the facial nerve was transected on both sides of the face. End-to-end suture was performed on the right side and fibrin sealant on the left side; (3) Experimental group with suture and laser (EGSL) and experimental group with fibrin and laser (EGFL). All animals underwent the same surgical procedures in the EGS and EGF groups, in combination with the application of LLLT (wavelength of 830 nm, 30 mW optical power output of potency, and energy density of 6 J/cm(2)). The animals of the five groups were euthanized at 5 weeks post-surgery and 10 weeks post-surgery. Axonal sprouting was observed in the distal stump of the facial nerve in all experimental groups. The observed morphology was similar to the fibers of the control group, with a predominance of myelinated fibers. In the final period of the experiment, the EGSL presented the closest results to the CG, in all variables measured, except in the axon area. Both surgical techniques analyzed were effective in the treatment of peripheral nerve injuries, where the use of fibrin sealant allowed the manipulation of the nerve stumps without trauma. LLLT exhibited satisfactory results on facial nerve regeneration, being therefore a useful technique to stimulate axonal regeneration process.

Intratemporal facial nerve ultrastructure in patients with idiopathic facial paralysis: viral infection evidence study.

PubMed

Florez, Rosangela Aló Maluza; Lang, Raquel; Veridiano, Adriano Mora; Zanini, Renato de Oliveira; Calió, Pedro Luiz; Simões, Ricardo Dos Santos; Testa, José Ricardo Gurgel

2010-01-01

The etiology of idiopathic peripheral facial palsy (IPFP) is still uncertain; however, some authors suggest the possibility of a viral infection. to analyze the ultrastructure of the facial nerve seeking viral evidences that might provide etiological data. We studied 20 patients with peripheral facial palsy (PFP), with moderate to severe FP, of both genders, between 18-60 years of age, from the Clinic of Facial Nerve Disorders. The patients were broken down into two groups - Study: eleven patients with IPFP and Control: nine patients with trauma or tumor-related PFP. The fragments were obtained from the facial nerve sheath or from fragments of its stumps - which would be discarded or sent to pathology exam during the facial nerve repair surgery. The removed tissue was fixed in 2% glutaraldehyde, and studied under Electronic Transmission Microscopy. In the study group we observed an intense repair cellular activity by increased collagen fibers, fibroblasts containing developed organelles, free of viral particles. In the control group this repair activity was not evident, but no viral particles were observed. There were no viral particles, and there were evidences of intense activity of repair or viral infection.

Chitosan conduits combined with nerve growth factor microspheres repair facial nerve defects

PubMed Central

Liu, Huawei; Wen, Weisheng; Hu, Min; Bi, Wenting; Chen, Lijie; Liu, Sanxia; Chen, Peng; Tan, Xinying

2013-01-01

Microspheres containing nerve growth factor for sustained release were prepared by a compound method, and implanted into chitosan conduits to repair 10-mm defects on the right buccal branches of the facial nerve in rabbits. In addition, chitosan conduits combined with nerve growth factor or normal saline, as well as autologous nerve, were used as controls. At 90 days post-surgery, the muscular atrophy on the right upper lip was more evident in the nerve growth factor and normal sa-line groups than in the nerve growth factor-microspheres and autologous nerve groups. physiological analysis revealed that the nerve conduction velocity and amplitude were significantly higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. Moreover, histological observation illustrated that the di-ameter, number, alignment and myelin sheath thickness of myelinated nerves derived from rabbits were higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. These findings indicate that chitosan nerve conduits bined with microspheres for sustained release of nerve growth factor can significantly improve facial nerve defect repair in rabbits. PMID:25206635

Transient Delayed Facial Nerve Palsy After Inferior Alveolar Nerve Block Anesthesia

PubMed Central

Tzermpos, Fotios H.; Cocos, Alina; Kleftogiannis, Matthaios; Zarakas, Marissa; Iatrou, Ioannis

2012-01-01

Facial nerve palsy, as a complication of an inferior alveolar nerve block anesthesia, is a rarely reported incident. Based on the time elapsed, from the moment of the injection to the onset of the symptoms, the paralysis could be either immediate or delayed. The purpose of this article is to report a case of delayed facial palsy as a result of inferior alveolar nerve block, which occurred 24 hours after the anesthetic administration and subsided in about 8 weeks. The pathogenesis, treatment, and results of an 8-week follow-up for a 20-year-old patient referred to a private maxillofacial clinic are presented and discussed. The patient's previous medical history was unremarkable. On clinical examination the patient exhibited generalized weakness of the left side of her face with a flat and expressionless appearance, and she was unable to close her left eye. One day before the onset of the symptoms, the patient had visited her dentist for a routine restorative procedure on the lower left first molar and an inferior alveolar block anesthesia was administered. The patient's medical history, clinical appearance, and complete examinations led to the diagnosis of delayed facial nerve palsy. Although neurologic occurrences are rare, dentists should keep in mind that certain dental procedures, such as inferior alveolar block anesthesia, could initiate facial nerve palsy. Attention should be paid during the administration of the anesthetic solution. PMID:22428971

Paeoniae alba Radix Promotes Peripheral Nerve Regeneration

PubMed Central

Huang, Kun-Shan; Lin, Jaung-Geng; Lee, Han-Chung; Tsai, Fuu-Jen; Bau, Da-Tian; Huang, Chih-Yang; Yao, Chun-Hsu; Chen, Yueh-Sheng

2011-01-01

The present study provides in vitro and in vivo evaluation of Paeoniae alba Radix (PR) on peripheral nerve regeneration. In the in vitro study, we found the PR caused a marked enhancement of the nerve growth factor-mediated neurite outgrowth from PC12 cells as well as their expression of growth associated protein 43 and synapsin I. In the in vivo study, silicone rubber chambers filled with the PR water extract were used to bridge a 10-mm sciatic nerve defect in rats. At the conclusion of 8 weeks, regenerated nerves in the PR groups, especially at 1.25 mg ml−1 had a higher rate of successful regeneration across the wide gap, relatively larger mean values of total nerve area, myelinated axon count and blood vessel number, and a significantly larger nerve conductive velocity compared to the control group (P  <  .05). These results suggest that the PR extract can be a potential nerve growth-promoting factor, being salutary in aiding the growth of injured peripheral nerve. PMID:19687191

Regeneration-associated genes on optic nerve regeneration in fish retina.

PubMed

Ogai, Kazuhiro; Nishitani, Maki; Kuwana, Ayaka; Mawatari, Kazuhiro; Koriyama, Yoshiki; Sugitani, Kayo; Nakashima, Hiroshi; Kato, Satoru

2014-01-01

It has been well documented that fish central nervous system, including retina and optic nerve, can regenerate and recover its function after nerve injury. Within a few decades, a number of regeneration-associated genes (RAGs) have been identified in fish retina following optic nerve injury (ONI). RAGs can be classified into two groups: cell survival- and axonal outgrowth-related genes. In fish retina after ONI, cell survival-related genes were upregulated in 1-6 days after ONI, which corresponds to the preparation stage for cell survival and axonal sprouting. Subsequently, axonal outgrowth-related genes were upregulated in 1-6 weeks after ONI, which corresponds to the axonal regrowth stage. Recently, we've found a novel type of RAGs, dedifferentiation-related genes, that are upregulated in overlapping time between cell survival and axonal regrowth (3-10 days after ONI). In this chapter we summarize these three types of RAGs that promote optic nerve regeneration in the fish retina after ONI.

Useful Method for Intraoperative Monitoring of Facial Nerve in a Scarred Bed.

PubMed

Aysal, Bilge Kagan; Yapici, Abdulkerim; Bayram, Yalcin; Zor, Fatih

2016-10-01

Facial nerve is the main cranial nerve for the innervation of facial expression muscles. Main trunk of facial nerve passes approximately 1 to 2 cm deep to tragal pointer. In some patients, where a patient has multiple operations, fibrosis due to previous operations may change the natural anatomy and direction of the branches of facial nerve. A 22-year-old male patient had 2 operations for mandibular reconstruction after gunshot wound. During the second operation, there was a possible injury to the marginal mandibular nerve and a nerve stimulator was used intraoperatively to monitor the nerve at the tragal pointer because the excitability of the distal segments remains intact for 24 to 48 hours after nerve injuries. Thus, using a nerve stimulator at the operational site may lead to false-positive muscle movements in case of injuries. Using the nerve stimulator to stimulate the main trunk at the tragal point may help to distinguish the presence of possible injuries. A reliable method for intraoperative facial nerve monitoring in a scarred operational site was introduced in this letter.

Shock wave treatment improves nerve regeneration in the rat.

PubMed

Mense, Siegfried; Hoheisel, Ulrich

2013-05-01

The aims of the experiments were to: (1) determine whether low-energy shock wave treatment accelerates the recovery of muscle sensitivity and functionality after a nerve lesion; and (2) assess the effect of shock waves on the regeneration of injured nerve fibers. After compression of a muscle nerve in rats the effects of shock wave treatment on the sequelae of the lesion were tested. In non-anesthetized animals, pressure pain thresholds and exploratory activity were determined. The influence of the treatment on the distance of nerve regeneration was studied in immunohistochemical experiments. Both behavioral and immunohistochemical data show that shock wave treatment accelerates the recovery of muscle sensitivity and functionality and promotes regeneration of injured nerve fibers. Treatment with focused shock waves induces an improvement of nerve regeneration in a rodent model of nerve compression. Copyright © 2012 Wiley Periodicals, Inc.

Nerve growth factor loaded heparin/chitosan scaffolds for accelerating peripheral nerve regeneration.

PubMed

Li, Guicai; Xiao, Qinzhi; Zhang, Luzhong; Zhao, Yahong; Yang, Yumin

2017-09-01

Artificial chitosan scaffolds have been widely investigated for peripheral nerve regeneration. However, the effect was not as good as that of autologous grafts and therefore could not meet the clinical requirement. In the present study, the nerve growth factor (NGF) loaded heparin/chitosan scaffolds were fabricated via electrostatic interaction for further improving nerve regeneration. The physicochemical properties including morphology, wettability and composition were measured. The heparin immobilization, NGF loading and release were quantitatively and qualitatively characterized, respectively. The effect of NGF loaded heparin/chitosan scaffolds on nerve regeneration was evaluated by Schwann cells culture for different periods. The results showed that the heparin immobilization and NGF loading did not cause the change of bulk properties of chitosan scaffolds except for morphology and wettability. The pre-immobilization of heparin in chitosan scaffolds could enhance the stability of subsequently loaded NGF. The NGF loaded heparin/chitosan scaffolds could obviously improve the attachment and proliferation of Schwann cells in vitro. More importantly, the NGF loaded heparin/chitosan scaffolds could effectively promote the morphology development of Schwann cells. The study may provide a useful experimental basis to design and develop artificial implants for peripheral nerve regeneration and other tissue regeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Useful surgical techniques for facial nerve preservation in tumorous intra-temporal lesions.

PubMed

Kim, Jin; Moon, In Seok; Lee, Jong Dae; Shim, Dae Bo; Lee, Won-Sang

2010-02-01

The management of the facial nerve in tumorous temporal lesions is particularly challenging due to its complex anatomic location and potential postoperative complications, including permanent facial paralysis. The most important concern regarding surgical treatment of a tumorous temporal lesion is the inevitable facial paralysis caused by nerve injury during the tumor removal, especially in patients with minimal to no preoperative facial nerve dysfunction. We describe successful four cases in which various surgical techniques were developed for the preservation of the facial nerve in treatment of intratemporal tumorous lesions. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Effect of Surface Pore Structure of Nerve Guide Conduit on Peripheral Nerve Regeneration

PubMed Central

Oh, Se Heang; Kim, Jin Rae; Kwon, Gu Birm; Namgung, Uk; Song, Kyu Sang

2013-01-01

Polycaprolactone (PCL)/Pluronic F127 nerve guide conduits (NGCs) with different surface pore structures (nano-porous inner surface vs. micro-porous inner surface) but similar physical and chemical properties were fabricated by rolling the opposite side of asymmetrically porous PCL/F127 membranes. The effect of the pore structure on peripheral nerve regeneration through the NGCs was investigated using a sciatic nerve defect model of rats. The nerve fibers and tissues were shown to have regenerated along the longitudinal direction through the NGC with a nano-porous inner surface (Nanopore NGC), while they grew toward the porous wall of the NGC with a micro-porous inner surface (Micropore NGC) and, thus, their growth was restricted when compared with the Nanopore NGC, as investigated by immunohistochemical evaluations (by fluorescence microscopy with anti-neurofilament staining and Hoechst staining for growth pattern of nerve fibers), histological evaluations (by light microscopy with Meyer's modified trichrome staining and Toluidine blue staining and transmission electron microscopy for the regeneration of axon and myelin sheath), and FluoroGold retrograde tracing (for reconnection between proximal and distal stumps). The effect of nerve growth factor (NGF) immobilized on the pore surfaces of the NGCs on nerve regeneration was not so significant when compared with NGCs not containing immobilized NGF. The NGC system with different surface pore structures but the same chemical/physical properties seems to be a good tool that is used for elucidating the surface pore effect of NGCs on nerve regeneration. PMID:22871377

The influence of predegenerated nerve grafts on axonal regeneration from prelesioned peripheral nerves.

PubMed

Hasan, N A; Neumann, M M; de Souky, M A; So, K F; Bedi, K S

1996-10-01

Recent in vitro work has indicated that predegenerated segments of peripheral nerve are more capable of supporting neurite growth from adult neurons than fresh segments of nerve, whereas previous in vivo studies which investigated whether predegenerated nerve segments used as grafts are capable of enhancing axonal regeneration produced conflicting results. We have reinvestigated this question by using predegenerated nerve grafts in combination with conditioning lesions of the host nerve to determine the optimal conditions for obtaining the maximal degree of regeneration of myelinated axons. The sciatic nerve of adult Dark Agouti rats were sectioned at midthigh level, and the distal portion was allowed to predegenerate for 0, 6 or 12 d in situ. 10-15 mm lengths of these distal nerve segments were then syngenically grafted onto the central stumps of sciatic nerves which had themselves received a conditioning lesion 0, 6, and 12 d previously, making a total of 9 different donor-host combinations. The grafts were assessed histologically 3 or 8 wk after grafting. Axonal regeneration in the 9 different donor-host combinations was determined by counting the numbers of myelinated axons in transverse sections through the grafts. All grafts examined contained regenerating myelinated axons. The rats given a 3 wk postgrafting survival period had an average of between 1400 and 5300 such axons. The rats given an 8 wk postgrafting survival period had between about 13,000 and 25,000 regenerating myelinated axons. Analysis of variance revealed significant main effects for both the Donor and Host conditions as well as Weeks (i.e. survival period after grafting). These results indicate that both a conditioning lesion of the host neurons and the degree of predegeneration of peripheral nerve segments to be used as grafts are of importance in influencing the degree of axonal regeneration. Of these 2 factors the conditioning lesion of the host appears to have the greater effect on the

Clinical predictors of facial nerve outcome after translabyrinthine resection of acoustic neuromas.

PubMed

Shamji, Mohammed F; Schramm, David R; Benoit, Brien G

2007-01-01

The translabyrinthine approach to acoustic neuroma resection offers excellent exposure for facial nerve dissection with 95% preservation of anatomic continuity. Acceptable outcome in facial asymptomatic patients is reported at 64-90%, but transient postoperative deterioration often occurs. The objective of this study was to identify preoperative clinical presentation and intraoperative surgical findings that predispose patients to facial nerve dysfunction after acoustic neuroma surgery. The charts of 128 consecutive translabyrinthine patients were examined retrospectively to identify new clinical and intraoperative predictors of facial nerve outcome. Postoperative evaluation of patients to normal function or mild asymmetry upon close inspection (House-Brackmann grades of I or II) was defined as an acceptable outcome, with obvious asymmetry to no movement (grades III to VI) defined as unacceptable. Intraoperative nerve stimulation was performed in all cases, and clinical grading was performed by a single neurosurgeon in all cases. Among patients with no preoperative facial nerve deficit, 87% had an acceptable result. Small size (P < 0.01) and low intraoperative nerve stimulation of < 0.10 mA (P< 0.01) were reaffirmed as predictive of functional nerve preservation. Additionally, preoperative tinnitus (P = 0.03), short duration of hearing loss (P< 0. 01), and lack of subjective tumour adherence to the facial nerve (P = 0.02) were independently correlated with positive outcome. Our experience with the translabyrinthine approach reveals the previously unestablished associations of facial nerve outcome to include presence of tinnitus and duration of hypoacusis. Independent predictors of tumour size and nerve stimulation thresholds were reaffirmed, and the subjective description of tumour adherence to the facial nerve making dissection more difficult appears to be important.

Electrical and transcranial magnetic stimulation of the facial nerve: diagnostic relevance in acute isolated facial nerve palsy.

PubMed

Happe, Svenja; Bunten, Sabine

2012-01-01

Unilateral facial weakness is common. Transcranial magnetic stimulation (TMS) allows identification of a conduction failure at the level of the canalicular portion of the facial nerve and may help to confirm the diagnosis. We retrospectively analyzed 216 patients with the diagnosis of peripheral facial palsy. The electrophysiological investigations included the blink reflex, preauricular electrical stimulation and the response to TMS at the labyrinthine part of the canalicular proportion of the facial nerve within 3 days after symptom onset. A similar reduction or loss of the TMS amplitude (p < 0.005) of the affected side was seen in each patient group. Of the 216 patients (107 female, mean age 49.7 ± 18.0 years), 193 were diagnosed with Bell's palsy. Test results of the remaining patients led to the diagnosis of infectious [including herpes simplex, varicella zoster infection and borreliosis (n = 13)] and noninfectious [including diabetes and neoplasma (n = 10)] etiology. A conduction block in TMS supports the diagnosis of peripheral facial palsy without being specific for Bell's palsy. These data shed light on the TMS-based diagnosis of peripheral facial palsy, an ability to localize the site of lesion within the Fallopian channel regardless of the underlying pathology. Copyright © 2012 S. Karger AG, Basel.

Engineering Bi-Layer Nanofibrous Conduits for Peripheral Nerve Regeneration

PubMed Central

Zhu, Yiqian; Wang, Aijun; Patel, Shyam; Kurpinski, Kyle; Diao, Edward; Bao, Xuan; Kwong, George; Young, William L.

2011-01-01

Trauma injuries often cause peripheral nerve damage and disability. A goal in neural tissue engineering is to develop synthetic nerve conduits for peripheral nerve regeneration having therapeutic efficacy comparable to that of autografts. Nanofibrous conduits with aligned nanofibers have been shown to promote nerve regeneration, but current fabrication methods rely on rolling a fibrous sheet into the shape of a conduit, which results in a graft with inconsistent size and a discontinuous joint or seam. In addition, the long-term effects of nanofibrous nerve conduits, in comparison with autografts, are still unknown. Here we developed a novel one-step electrospinning process and, for the first time, fabricated a seamless bi-layer nanofibrous nerve conduit: the luminal layer having longitudinally aligned nanofibers to promote nerve regeneration, and the outer layer having randomly organized nanofibers for mechanical support. Long-term in vivo studies demonstrated that bi-layer aligned nanofibrous nerve conduits were superior to random nanofibrous conduits and had comparable therapeutic effects to autografts for nerve regeneration. In summary, we showed that the engineered nanostructure had a significant impact on neural tissue regeneration in situ. The results from this study will also lead to the scalable fabrication of engineered nanofibrous nerve conduits with designed nanostructure. This technology platform can be combined with drug delivery and cell therapies for tissue engineering. PMID:21501089

Use of a Y-tube conduit after facial nerve injury reduces collateral axonal branching at the lesion site but neither reduces polyinnervation of motor endplates nor improves functional recovery.

PubMed

Hizay, Arzu; Ozsoy, Umut; Demirel, Bahadir Murat; Ozsoy, Ozlem; Angelova, Srebrina K; Ankerne, Janina; Sarikcioglu, Sureyya Bilmen; Dunlop, Sarah A; Angelov, Doychin N; Sarikcioglu, Levent

2012-06-01

Despite increased understanding of peripheral nerve regeneration, functional recovery after surgical repair remains disappointing. A major contributing factor is the extensive collateral branching at the lesion site, which leads to inaccurate axonal navigation and aberrant reinnervation of targets. To determine whether the Y tube reconstruction improved axonal regrowth and whether this was associated with improved function. We used a Y-tube conduit with the aim of improving navigation of regenerating axons after facial nerve transection in rats. Retrograde labeling from the zygomatic and buccal branches showed a halving in the number of double-labeled facial motor neurons (15% vs 8%; P < .05) after Y tube reconstruction compared with facial-facial anastomosis coaptation. However, in both surgical groups, the proportion of polyinnervated motor endplates was similar (≈ 30%; P > .05), and video-based motion analysis of whisking revealed similarly poor function. Although Y-tube reconstruction decreases axonal branching at the lesion site and improves axonal navigation compared with facial-facial anastomosis coaptation, it fails to promote monoinnervation of motor endplates and confers no functional benefit.

Duplicated facial nerve trunk with a first branchial cleft cyst.

PubMed

Hinson, Drew; Poteet, Perry; Bower, Charles

2014-03-01

First branchial cleft anomalies are rare and their various anatomical relationships to the facial nerve have been described. We encountered a 15-year-old female with a type II first branchial cleft cyst presenting as a right neck mass that we found during surgical excision to transverse two main facial nerve trunks. To our knowledge, this is the first reported case of a first branchial cleft anomaly in conjunction with a duplicated facial nerve trunk. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Silk fibroin enhances peripheral nerve regeneration by improving vascularization within nerve conduits.

PubMed

Wang, Chunyang; Jia, Yachao; Yang, Weichao; Zhang, Cheng; Zhang, Kuihua; Chai, Yimin

2018-07-01

Silk fibroin (SF)-based nerve conduits have been widely used to bridge peripheral nerve defects. Our previous study showed that nerve regeneration in a SF-blended poly (l-lactide-co-ɛ-caprolactone) [P(LLA-CL)] nerve conduit is better than that in a P(LLA-CL) conduit. However, the involved mechanisms remain unclarified. Because angiogenesis within a nerve conduit plays an important role in nerve regeneration, vascularization of SF/P(LLA-CL) and P(LLA-CL) conduits was compared both in vitro and in vivo. In the present study, we observed that SF/P(LLA-CL) nanofibers significantly promoted fibroblast proliferation, and vascular endothelial growth factor secreted by fibroblasts seeded in SF/P(LLA-CL) nanofibers was more than seven-fold higher than that in P(LLA-CL) nanofibers. Conditioned medium of fibroblasts in the SF/P(LLA-CL) group stimulated more human umbilical vein endothelial cells (HUVEC) to form capillary-like networks and promoted faster HUVEC migration. The two kinds of nerve conduits were used to bridge 10-mm-length nerve defects in rats. At 3 weeks of reparation, the blood vessel area in the SF/P(LLA-CL) group was significantly larger than that in the P(LLA-CL) group. More regenerated axons and Schwann cells were also observed in the SF/P(LLA-CL) group, which was consistent with the results of blood vessels. Collectively, our data revealed that the SF/P(LLA-CL) nerve conduit enhances peripheral nerve regeneration by improving angiogenesis within the conduit. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2070-2077, 2018. © 2018 Wiley Periodicals, Inc.

Masseteric-facial nerve transposition for reanimation of the smile in incomplete facial paralysis.

PubMed

Hontanilla, Bernardo; Marre, Diego

2015-12-01

Incomplete facial paralysis occurs in about a third of patients with Bell's palsy. Although their faces are symmetrical at rest, when they smile they have varying degrees of disfigurement. Currently, cross-face nerve grafting is one of the most useful techniques for reanimation. Transfer of the masseteric nerve, although widely used for complete paralysis, has not to our knowledge been reported for incomplete palsy. Between December 2008 and November 2013, we reanimated the faces of 9 patients (2 men and 7 women) with incomplete unilateral facial paralysis with transposition of the masseteric nerve. Sex, age at operation, cause of paralysis, duration of denervation, recipient nerves used, and duration of follow-up were recorded. Commissural excursion, velocity, and patients' satisfaction were evaluated with the FACIAL CLIMA and a questionnaire, respectively. The mean (SD) age at operation was 39 (±6) years and the duration of denervation was 29 (±19) months. There were no complications that required further intervention. Duration of follow-up ranged from 6-26 months. FACIAL CLIMA showed improvement in both commissural excursion and velocity of more than two thirds in 6 patients, more than one half in 2 patients and less than one half in one. Qualitative evaluation showed a slight or pronounced improvement in 7/9 patients. The masseteric nerve is a reliable alternative for reanimation of the smile in patients with incomplete facial paralysis. Its main advantages include its consistent anatomy, a one-stage operation, and low morbidity at the donor site. Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Improved Facial Nerve Identification During Parotidectomy With Fluorescently Labeled Peptide

PubMed Central

Hussain, Timon; Nguyen, Linda T.; Whitney, Michael; Hasselmann, Jonathan; Nguyen, Quyen T.

2016-01-01

Objectives/Hypothesis Additional intraoperative guidance could reduce the risk of iatrogenic injury during parotid gland cancer surgery. We evaluated the intraoperative use of fluorescently labeled nerve binding peptide NP41 to aid facial nerve identification and preservation during parotidectomy in an orthotopic model of murine parotid gland cancer. We also quantified the accuracy of intraoperative nerve detection for surface and buried nerves in the head and neck with NP41 versus white light (WL) alone. Study Design Twenty-eight mice underwent parotid gland cancer surgeries with additional fluorescence (FL) guidance versus WL reflectance (WLR) alone. Eight mice were used for additional nerve-imaging experiments. Methods Twenty-eight parotid tumor-bearing mice underwent parotidectomy. Eight mice underwent imaging of both sides of the face after skin removal. Postoperative assessment of facial nerve function measured by automated whisker tracking were compared between FL guidance (n = 13) versus WL alone (n = 15). In eight mice, nerve to surrounding tissue contrast was measured under FL versus WLR for all nerve branches detectable in the field of view. Results Postoperative facial nerve function after parotid gland cancer surgery tended to be better with additional FL guidance. Fluorescent labeling significantly improved nerve to surrounding tissue contrast for both large and smaller buried nerve branches compared to WLR visualization and improved detection sensitivity and specificity. Conclusions NP41 FL imaging significantly aids the intraoperative identification of nerve braches otherwise nearly invisible to the naked eye. Its application in a murine model of parotid gland cancer surgery tended to improve functional preservation of the facial nerve. PMID:27171862

Curcumin promotes nerve regeneration and functional recovery after sciatic nerve crush injury in diabetic rats.

PubMed

Ma, Junxiong; Yu, Hailong; Liu, Jun; Chen, Yu; Wang, Qi; Xiang, Liangbi

2016-01-01

Curcumin is capable of promoting peripheral nerve regeneration in normal condition. However, it is unclear whether its beneficial effect on nerve regeneration still exists under diabetic mellitus. The present study was designed to investigate such a possibility. Diabetes in rats was developed by a single dose of streptozotocin at 50 mg/kg. Immediately after nerve crush injury, the diabetic rats were intraperitoneally administrated daily for 4 weeks with curcumin (50 mg/kg, 100 mg/kg and 300 mg/kg), or normal saline, respectively. The axonal regeneration was investigated by morphometric analysis and retrograde labeling. The functional recovery was evaluated by electrophysiological studies and behavioral analysis. Axonal regeneration and functional recovery was significantly enhanced by curcumin, which were significantly better than those in vehicle saline group. In addition, high doses of curcumin (100 mg/kg and 300 mg/kg) achieved better axonal regeneration and functional recovery than low dose (50 mg/kg). In conclusion, curcumin is capable of promoting nerve regeneration after sciatic nerve crush injury in diabetes mellitus, highlighting its therapeutic values as a neuroprotective agent for peripheral nerve injury repair in diabetes mellitus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Measurement of facial movements with Photoshop software during treatment of facial nerve palsy.

PubMed

Pourmomeny, Abbas Ali; Zadmehr, Hassan; Hossaini, Mohsen

2011-10-01

Evaluating the function of facial nerve is essential in order to determine the influences of various treatment methods. The aim of this study was to evaluate and assess the agreement of Photoshop scaling system versus the facial grading system (FGS). In this semi-experimental study, thirty subjects with facial nerve paralysis were recruited. The evaluation of all patients before and after the treatment was performed by FGS and Photoshop measurements. The mean values of FGS before and after the treatment were 35 ± 25 and 67 ± 24, respectively (p < 0.001). In Photoshop assessment, mean changes of face expressions in the impaired side relative to the normal side in rest position and three main movements of the face were 3.4 ± 0.55 and 4.04 ± 0.49 millimeter before and after the treatment, respectively (p < 0.001). Spearman's correlation coefficient between different values in the two methods was 0.66 (p < 0.001). Evaluating the facial nerve palsy using Photoshop was more objective than using FGS. Therefore, it may be recommended to use this method instead.

Improved facial nerve identification during parotidectomy with fluorescently labeled peptide.

PubMed

Hussain, Timon; Nguyen, Linda T; Whitney, Michael; Hasselmann, Jonathan; Nguyen, Quyen T

2016-12-01

Additional intraoperative guidance could reduce the risk of iatrogenic injury during parotid gland cancer surgery. We evaluated the intraoperative use of fluorescently labeled nerve binding peptide NP41 to aid facial nerve identification and preservation during parotidectomy in an orthotopic model of murine parotid gland cancer. We also quantified the accuracy of intraoperative nerve detection for surface and buried nerves in the head and neck with NP41 versus white light (WL) alone. Twenty-eight mice underwent parotid gland cancer surgeries with additional fluorescence (FL) guidance versus WL reflectance (WLR) alone. Eight mice were used for additional nerve-imaging experiments. Twenty-eight parotid tumor-bearing mice underwent parotidectomy. Eight mice underwent imaging of both sides of the face after skin removal. Postoperative assessment of facial nerve function measured by automated whisker tracking were compared between FL guidance (n = 13) versus WL alone (n=15). In eight mice, nerve to surrounding tissue contrast was measured under FL versus WLR for all nerve branches detectable in the field of view. Postoperative facial nerve function after parotid gland cancer surgery tended to be better with additional FL guidance. Fluorescent labeling significantly improved nerve to surrounding tissue contrast for both large and smaller buried nerve branches compared to WLR visualization and improved detection sensitivity and specificity. NP41 FL imaging significantly aids the intraoperative identification of nerve braches otherwise nearly invisible to the naked eye. Its application in a murine model of parotid gland cancer surgery tended to improve functional preservation of the facial nerve. NA Laryngoscope, 126:2711-2717, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Retrospective case series of the imaging findings of facial nerve hemangioma.

PubMed

Yue, Yunlong; Jin, Yanfang; Yang, Bentao; Yuan, Hui; Li, Jiandong; Wang, Zhenchang

2015-09-01

The aim was to compare high-resolution computed tomography (HRCT) and thin-section magnetic resonance imaging (MRI) findings of facial nerve hemangioma. The HRCT and MRI characteristics of 17 facial nerve hemangiomas diagnosed between 2006 and 2013 were retrospectively analyzed. All patients included in the study suffered from a space-occupying lesion of soft tissues at the geniculate ganglion fossa. Affected nerve was compared for size and shape with the contralateral unaffected nerve. HRCT showed irregular expansion and broadening of the facial nerve canal, damage of the bone wall and destruction of adjacent bone, with "point"-like or "needle"-like calcifications in 14 cases. The average CT value was 320.9 ± 141.8 Hu. Fourteen patients had a widened labyrinthine segment; 6/17 had a tympanic segment widening; 2/17 had a greater superficial petrosal nerve canal involvement, and 2/17 had an affected internal auditory canal (IAC) segment. On MRI, all lesions were significantly enhanced due to high blood supply. Using 2D FSE T2WI, the lesion detection rate was 82.4 % (14/17). 3D fast imaging employing steady-state acquisition (3D FIESTA) revealed the lesions in all patients. HRCT showed that the average number of involved segments in the facial nerve canal was 2.41, while MRI revealed an average of 2.70 segments (P < 0.05). HRCT and MR findings of facial nerve hemangioma were typical, revealing irregular masses growing along the facial nerve canal, with calcifications and rich blood supply. Thin-section enhanced MRI was more accurate in lesion detection and assessment compared with HRCT.

Cutaneous electrical stimulation treatment in unresolved facial nerve paralysis: an exploratory study.

PubMed

Hyvärinen, Antti; Tarkka, Ina M; Mervaala, Esa; Pääkkönen, Ari; Valtonen, Hannu; Nuutinen, Juhani

2008-12-01

The purpose of this study was to assess clinical and neurophysiological changes after 6 mos of transcutaneous electrical stimulation in patients with unresolved facial nerve paralysis. A pilot case series of 10 consecutive patients with chronic facial nerve paralysis either of idiopathic origin or because of herpes zoster oticus participated in this open study. All patients received below sensory threshold transcutaneous electrical stimulation for 6 mos for their facial nerve paralysis. The intervention consisted of gradually increasing the duration of electrical stimulation of three sites on the affected area for up to 6 hrs/day. Assessments of the facial nerve function were performed using the House-Brackmann clinical scale and neurophysiological measurements of compound motor action potential distal latencies on the affected and nonaffected sides. Patients were tested before and after the intervention. A significant improvement was observed in the facial nerve upper branch compound motor action potential distal latency on the affected side in all patients. An improvement of one grade in House-Brackmann scale was observed and some patients also reported subjective improvement. Transcutaneous electrical stimulation treatment may have a positive effect on unresolved facial nerve paralysis. This study illustrates a possibly effective treatment option for patients with the chronic facial paresis with no other expectations of recovery.

Correlations between the clinical, histological and neurophysiological examinations in patients before and after parotid gland tumor surgery: verification of facial nerve transmission.

PubMed

Wiertel-Krawczuk, Agnieszka; Huber, Juliusz; Wojtysiak, Magdalena; Golusiński, Wojciech; Pieńkowski, Piotr; Golusiński, Paweł

2015-05-01

Parotid gland tumor surgery sometimes leads to facial nerve paralysis. Malignant more than benign tumors determine nerve function preoperatively, while postoperative observations based on clinical, histological and neurophysiological studies have not been reported in detail. The aims of this pilot study were evaluation and correlations of histological properties of tumor (its size and location) and clinical and neurophysiological assessment of facial nerve function pre- and post-operatively (1 and 6 months). Comparative studies included 17 patients with benign (n = 13) and malignant (n = 4) tumors. Clinical assessment was based on House-Brackmann scale (H-B), neurophysiological diagnostics included facial electroneurography [ENG, compound muscle action potential (CMAP)], mimetic muscle electromyography (EMG) and blink-reflex examinations (BR). Mainly grade I of H-B was recorded both pre- (n = 13) and post-operatively (n = 12) in patients with small (1.5-2.4 cm) benign tumors located in superficial lobes. Patients with medium size (2.5-3.4 cm) malignant tumors in both lobes were scored at grade I (n = 2) and III (n = 2) pre- and mainly VI (n = 4) post-operatively. CMAP amplitudes after stimulation of mandibular marginal branch were reduced at about 25 % in patients with benign tumors after surgery. In the cases of malignant tumors CMAPs were not recorded following stimulation of any branch. A similar trend was found for BR results. H-B and ENG results revealed positive correlations between the type of tumor and surgery with facial nerve function. Neurophysiological studies detected clinically silent facial nerve neuropathy of mandibular marginal branch in postoperative period. Needle EMG, ENG and BR examinations allow for the evaluation of face muscles reinnervation and facial nerve regeneration.

Mime therapy improves facial symmetry in people with long-term facial nerve paresis: a randomised controlled trial.

PubMed

Beurskens, Carien H G; Heymans, Peter G

2006-01-01

What is the effect of mime therapy on facial symmetry and severity of paresis in people with facial nerve paresis? Randomised controlled trial. 50 people recruited from the Outpatient department of two metropolitan hospitals with facial nerve paresis for more than nine months. The experimental group received three months of mime therapy consisting of massage, relaxation, inhibition of synkinesis, and co-ordination and emotional expression exercises. The control group was placed on a waiting list. Assessments were made on admission to the trial and three months later by a measurer blinded to group allocation. Facial symmetry was measured using the Sunnybrook Facial Grading System. Severity of paresis was measured using the House-Brackmann Facial Grading System. After three months of mime therapy, the experimental group had improved their facial symmetry by 20.4 points (95% CI 10.4 to 30.4) on the Sunnybrook Facial Grading System compared with the control group. In addition, the experimental group had reduced the severity of their paresis by 0.6 grade (95% CI 0.1 to 1.1) on the House-Brackmann Facial Grading System compared with the control group. These effects were independent of age, sex, and duration of paresis. Mime therapy improves facial symmetry and reduces the severity of paresis in people with facial nerve paresis.

Measurement of facial movements with Photoshop software during treatment of facial nerve palsy*

PubMed Central

Pourmomeny, Abbas Ali; Zadmehr, Hassan; Hossaini, Mohsen

2011-01-01

BACKGROUND: Evaluating the function of facial nerve is essential in order to determine the influences of various treatment methods. The aim of this study was to evaluate and assess the agreement of Photoshop scaling system versus the facial grading system (FGS). METHODS: In this semi-experimental study, thirty subjects with facial nerve paralysis were recruited. The evaluation of all patients before and after the treatment was performed by FGS and Photoshop measurements. RESULTS: The mean values of FGS before and after the treatment were 35 ± 25 and 67 ± 24, respectively (p < 0.001). In Photoshop assessment, mean changes of face expressions in the impaired side relative to the normal side in rest position and three main movements of the face were 3.4 ± 0.55 and 4.04 ± 0.49 millimeter before and after the treatment, respectively (p < 0.001). Spearman's correlation coefficient between different values in the two methods was 0.66 (p < 0.001). CONCLUSIONS: Evaluating the facial nerve palsy using Photoshop was more objective than using FGS. Therefore, it may be recommended to use this method instead. PMID:22973325

[Dynamics of lagophthalmos depending on facial nerve repair and its intraoperative monitoring in neurosurgical patients].

PubMed

Tabachnikova, T V; Serova, N K; Shimansky, V N

2014-01-01

Over 200 patients with acoustic neuromas and over 100 patients with posterior cranial fossa meningiomas are annually operated on at the N.N. Burdenko Neurosurgical Institute. Intraoperative monitoring of the facial nerve function is used in most patients with tumors of the posterior cranial fossa to identify the facial nerve in the surgical wound. If the anatomical integrity of the facial nerve in the cranial cavity cannot be retained, facial nerve repair is performed to restore the facial muscle function. Intraoperative electrical stimulation of the facial nerve has a great prognostic significance to evaluate the dynamics of lagophthalmos in the late postoperative period and to select the proper method for lagophthalmos correction. When the facial nerve was reinnervated by the descending branch or trunk of the hypoglossal nerve, sufficient eyelid closure was observed only in 3 patients out of 17.

Evoked electromyography to rocuronium in orbicularis oris and gastrocnemius in facial nerve injury in rabbits.

PubMed

Xing, Yian; Chen, Lianhua; Li, Shitong

2013-11-01

Muscles innervated by the facial nerve show different sensitivities to muscle relaxants than muscles innervated by somatic nerves, especially in the presence of facial nerve injury. We compared the evoked electromyography (EEMG) response of orbicularis oris and gastrocnemius in with and without a non-depolarizing muscle relaxant in a rabbit model of graded facial nerve injury. Differences in EEMG response and inhibition by rocuronium were measured in the orbicularis oris and gastrocnemius muscles 7 to 42 d after different levels of facial nerve crush injuries in adult rabbits. Baseline EEMG of orbicularis oris was significantly smaller than those of the gastrocnemius. Gastrocnemius was more sensitive to rocuronium than the facial muscles (P < 0.05). Baseline EEMG and EEMG amplitude of orbicularis oris in the presence of rocuronium was negatively correlated with the magnitude of facial nerve injury but the sensitivity to rocuronium was not. No significant difference was found in the onset time and the recovery time of rocuronium among gastrocnemius and normal or damaged facial muscles. Muscles innervated by somatic nerves are more sensitive to rocuronium than those innervated by the facial nerve, but while facial nerve injury reduced EEMG responses, the sensitivity to rocuronium is not altered. Partial neuromuscular blockade may be a suitable technique for conducting anesthesia and surgery safely when EEMG monitoring is needed to preserve and protect the facial nerve. Additional caution should be used if there is a risk of preexisting facial nerve injury. Copyright © 2013 Elsevier Inc. All rights reserved.

Prognostic significance of electrophysiological tests for facial nerve outcome in vestibular schwannoma surgery.

PubMed

van Dinther, J J S; Van Rompaey, V; Somers, T; Zarowski, A; Offeciers, F E

2011-01-01

To assess the prognostic significance of pre-operative electrophysiological tests for facial nerve outcome in vestibular schwannoma surgery. Retrospective study design in a tertiary referral neurology unit. We studied a total of 123 patients with unilateral vestibular schwannoma who underwent microsurgical removal of the lesion. Nine patients were excluded because they had clinically abnormal pre-operative facial function. Pre-operative electrophysiological facial nerve function testing (EPhT) was performed. Short-term (1 month) and long-term (1 year) post-operative clinical facial nerve function were assessed. When pre-operative facial nerve function, evaluated by EPhT, was normal, the outcome from clinical follow-up at 1-month post-operatively was excellent in 78% (i.e. HB I-II) of patients, moderate in 11% (i.e. HB III-IV), and bad in 11% (i.e. HB V-VI). After 1 year, 86% had excellent outcomes, 13% had moderate outcomes, and 1% had bad outcomes. Of all patients with normal clinical facial nerve function, 22% had an abnormal EPhT result and 78% had a normal result. No statistically significant differences could be observed in short-term and long-term post-operative facial function between the groups. In this study, electrophysiological tests were not able to predict facial nerve outcome after vestibular schwannoma surgery. Tumour size remains the best pre-operative prognostic indicator of facial nerve function outcome, i.e. a better outcome in smaller lesions.

The masseteric nerve: a versatile power source in facial animation techniques.

PubMed

Bianchi, B; Ferri, A; Ferrari, S; Copelli, C; Salvagni, L; Sesenna, E

2014-03-01

The masseteric nerve has many advantages including low morbidity, its proximity to the facial nerve, the strong motor impulse, its reliability, and the fast reinnervation that is achievable in most patients. Reinnervation of a neuromuscular transplant is the main indication for its use, but it has been used for the treatment of recent facial palsies with satisfactory results. We have retrospectively evaluated 60 patients who had facial animation procedures using the masseteric nerve during the last 10 years. The patients included those with recent, and established or congenital, unilateral and bilateral palsies. The masseteric nerve was used for coaptation of the facial nerve either alone or in association with crossfacial nerve grafting, or for the reinnervation of gracilis neuromuscular transplants. Reinnervation was successful in all cases, the mean (range) time being 4 (2-5) months for facial nerve coaptation and 4 (3-7) months for neuromuscular transplants. Cosmesis was evaluated (moderate, n=10, good, n=30, and excellent, n=20) as was functional outcome (no case of impairment of masticatory function, all patients able to smile, and achievement of a smile independent from biting). The masseteric nerve has many uses, including in both recent, and established or congenital, cases. In some conditions it is the first line of treatment. The combination of combined techniques gives excellent results in unilateral palsies and should therefore be considered a valid option. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

End-to-side neurorrhaphy repairs peripheral nerve injury: sensory nerve induces motor nerve regeneration.

PubMed

Yu, Qing; Zhang, She-Hong; Wang, Tao; Peng, Feng; Han, Dong; Gu, Yu-Dong

2017-10-01

End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve. It involves suturing the distal stump of the disconnected nerve (recipient nerve) to the side of the intimate adjacent nerve (donor nerve). However, the motor-sensory specificity after end-to-side neurorrhaphy remains unclear. This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy. Thirty rats were randomized into three groups: (1) end-to-side neurorrhaphy using the ulnar nerve (mixed sensory and motor) as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve; (2) the sham group: ulnar nerve and cutaneous antebrachii medialis nerve were just exposed; and (3) the transected nerve group: cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied. At 5 months, acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group, and none of the myelinated axons were stained in either the sham or transected nerve groups. Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%. In contrast, no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment. These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy.

End-to-side neurorrhaphy repairs peripheral nerve injury: sensory nerve induces motor nerve regeneration

PubMed Central

Yu, Qing; Zhang, She-hong; Wang, Tao; Peng, Feng; Han, Dong; Gu, Yu-dong

2017-01-01

End-to-side neurorrhaphy is an option in the treatment of the long segment defects of a nerve. It involves suturing the distal stump of the disconnected nerve (recipient nerve) to the side of the intimate adjacent nerve (donor nerve). However, the motor-sensory specificity after end-to-side neurorrhaphy remains unclear. This study sought to evaluate whether cutaneous sensory nerve regeneration induces motor nerves after end-to-side neurorrhaphy. Thirty rats were randomized into three groups: (1) end-to-side neurorrhaphy using the ulnar nerve (mixed sensory and motor) as the donor nerve and the cutaneous antebrachii medialis nerve as the recipient nerve; (2) the sham group: ulnar nerve and cutaneous antebrachii medialis nerve were just exposed; and (3) the transected nerve group: cutaneous antebrachii medialis nerve was transected and the stumps were turned over and tied. At 5 months, acetylcholinesterase staining results showed that 34% ± 16% of the myelinated axons were stained in the end-to-side group, and none of the myelinated axons were stained in either the sham or transected nerve groups. Retrograde fluorescent tracing of spinal motor neurons and dorsal root ganglion showed the proportion of motor neurons from the cutaneous antebrachii medialis nerve of the end-to-side group was 21% ± 5%. In contrast, no motor neurons from the cutaneous antebrachii medialis nerve of the sham group and transected nerve group were found in the spinal cord segment. These results confirmed that motor neuron regeneration occurred after cutaneous nerve end-to-side neurorrhaphy. PMID:29171436

Deep Temporal Nerve Transfer for Facial Reanimation: Anatomic Dissections and Surgical Case Report.

PubMed

Mahan, Mark A; Sivakumar, Walavan; Weingarten, David; Brown, Justin M

2017-09-08

Facial nerve palsy is a disabling condition that may arise from a variety of injuries or insults and may occur at any point along the nerve or its intracerebral origin. To examine the use of the deep temporal branches of the motor division of the trigeminal nerve for neural reconstruction of the temporal branches of the facial nerve for restoration of active blink and periorbital facial expression. Formalin-fixed human cadaver hemifaces were dissected to identify landmarks for the deep temporal branches and the tension-free coaptation lengths. This technique was then utilized in 1 patient with a history of facial palsy due to a brainstem cavernoma. Sixteen hemifaces were dissected. The middle deep temporal nerve could be consistently identified on the deep side of the temporalis, within 9 to 12 mm posterior to the jugal point of the zygoma. From a lateral approach through the temporalis, the middle deep temporal nerve could be directly coapted to facial temporal branches in all specimens. Our patient has recovered active and independent upper facial muscle contraction, providing the first case report of a distinct distal nerve transfer for upper facial function. The middle deep temporal branches can be readily identified and utilized for facial reanimation. This technique provided a successful reanimation of upper facial muscles with independent activation. Utilizing multiple sources for neurotization of the facial muscles, different potions of the face can be selectively reanimated to reduce the risk of synkinesis and improved control. Copyright © 2017 by the Congress of Neurological Surgeons

Surgical management of internal auditory canal and cerebellopontine angle facial nerve schwannoma

PubMed Central

Mowry, Sarah; Hansen, Marlan; Gantz, Bruce

2013-01-01

Objective To investigate the long-term patient outcomes following tumor debulking for internal auditory canal facial schwannoma (FNS). Study Design retrospective case review Setting Tertiary referral center Patients Patients operated on between 1998–2010 for a preoperative diagnosis of vestibular schwannoma with the intraoperative identification FNS instead. Intervention diagnostic and therapeutic Main Outcome Measures House-Brackmann facial nerve score immediately and at long term follow up (>1 yr); recurrence of tumor. Results 16 patients were identified who were presumed to have vestibular schwannoma but intraoperatively were diagnosed with facial nerve schwannoma. Eleven underwent debulking surgery (67%–99% tumor removal), 2 underwent decompression only, 2 were diagnosed with nervus intermedius tumors and had total tumor removal with preservation of the motor branch of CN VII, 1 had complete tumor removal with facial nerve grafting. Five of 11 debulking patients underwent the MCF approach for tumor removal; the remainder had translabyrinthine resections. One debulking patient was lost to follow-up. Nine of 10 patients with long term follow up had H/B grade I or II facial function. One patient had recurrence of the tumor that required revision surgery with total removal and facial nerve grafting. Conclusions Tumor debulking for FNS provides an opportunity for tumor removal and excellent facial nerve function. Continuous facial nerve monitoring is vital for successful debulking surgery. FNS debulking is feasible via the MCF approach. Serial postoperative imaging is warranted to monitor for recurrence. PMID:22772011

A Neuromonitoring Approach to Facial Nerve Preservation During Image-guided Robotic Cochlear Implantation.

PubMed

Ansó, Juan; Dür, Cilgia; Gavaghan, Kate; Rohrbach, Helene; Gerber, Nicolas; Williamson, Tom; Calvo, Enric M; Balmer, Thomas Wyss; Precht, Christina; Ferrario, Damien; Dettmer, Matthias S; Rösler, Kai M; Caversaccio, Marco D; Bell, Brett; Weber, Stefan

2016-01-01

A multielectrode probe in combination with an optimized stimulation protocol could provide sufficient sensitivity and specificity to act as an effective safety mechanism for preservation of the facial nerve in case of an unsafe drill distance during image-guided cochlear implantation. A minimally invasive cochlear implantation is enabled by image-guided and robotic-assisted drilling of an access tunnel to the middle ear cavity. The approach requires the drill to pass at distances below 1  mm from the facial nerve and thus safety mechanisms for protecting this critical structure are required. Neuromonitoring is currently used to determine facial nerve proximity in mastoidectomy but lacks sensitivity and specificity necessaries to effectively distinguish the close distance ranges experienced in the minimally invasive approach, possibly because of current shunting of uninsulated stimulating drilling tools in the drill tunnel and because of nonoptimized stimulation parameters. To this end, we propose an advanced neuromonitoring approach using varying levels of stimulation parameters together with an integrated bipolar and monopolar stimulating probe. An in vivo study (sheep model) was conducted in which measurements at specifically planned and navigated lateral distances from the facial nerve were performed to determine if specific sets of stimulation parameters in combination with the proposed neuromonitoring system could reliably detect an imminent collision with the facial nerve. For the accurate positioning of the neuromonitoring probe, a dedicated robotic system for image-guided cochlear implantation was used and drilling accuracy was corrected on postoperative microcomputed tomographic images. From 29 trajectories analyzed in five different subjects, a correlation between stimulus threshold and drill-to-facial nerve distance was found in trajectories colliding with the facial nerve (distance <0.1  mm). The shortest pulse duration that provided the highest

[Facial nerve monitoring during middle ear surgery: Results of a French survey].

PubMed

Mazzaschi, O; Juvanon, J-M; Mondain, M; Lavieile, J-P; Ayache, D

2014-01-01

Facial nerve injury is a rare complication of middle ear surgery. To date there is no widely accepted consensus on the use of intraoperative facial nerve monitoring during middle ear surgery, whereas its use has been proved as a valuable adjunct in neurotologic surgery. The purpose of our study was to identify introperative facial nerve monitoring practice patterns in France for middle ear surgery. A 19-item survey has been made up by three experienced otologists under the auspices of the French Otology and Neurotology Association. With the support of the French Society of Otolaryngology--Head and Neck Surgery, the survey was electronically sent by email to 1249 practicing ENT with a valid email address. Answers were analyzed two months later. Among 1249 email sent, 299 were opened (24%) and 83 answers were collected (6,6%). Of the respondents, 66% had access to intraoperative facial nerve monitoring. Otolaryngologists involved in academic setting were influenced by their teaching duty in 27%. Intraoperative facial nerve monitoring should not be required for stapes surgery, ossiculoplasty, myringoplasty for, respectively, 92%, 93 % and 98% of the respondents. In cochlear implantation, 78% of ear surgeons used facial nerve monitoring. Answers were more controversial for chronic ear surgery, ear atresia and middle ear implant. Revision surgery and CT scan can influence answers. Despite a low response rate, results of this national survey revealed interesting findings. For most of the respondents, intraoperative facial nerve monitoring was not indicated in stapes surgery, myringoplasty and ossiculoplasty. The use of intraoperative facial nerve monitoring for cochlear implantation was supported by the majority of respondents. Variations in response rate were more significant for chronic ear surgery, including middle ear cholesteatoma, and for ear atresia surgery.

Polymer Scaffolds with Preferential Parallel Grooves Enhance Nerve Regeneration

PubMed Central

Mobasseri, Atefeh; Faroni, Alessandro; Minogue, Ben M.; Downes, Sandra; Reid, Adam J.

2015-01-01

We have modified the surface topography of poly ɛ-caprolactone (PCL) and polylactic acid (PLA) blended films to improve cell proliferation and to guide the regeneration of peripheral nerves. Films with differing shaped grooves were made using patterned silicon templates, sloped walls (SL), V-shaped (V), and square-shaped (SQ), and compared with nongrooved surfaces with micropits. The solvent cast films were tested in vitro using adult adipose-derived stem cells differentiated to Schwann cell-like cells. Cell attachment, proliferation, and cell orientation were all improved on the grooved surfaces, with SL grooves giving the best results. We present in vivo data on Sprague-Dawley rat sciatic nerve injury with a 10-mm gap, evaluating nerve regeneration at 3 weeks across a polymer nerve conduit modified with intraluminal grooves (SL, V, and SQ) and differing wall thicknesses (70, 100, 120, and 210 μm). The SL-grooved nerve conduit showed a significant improvement over the other topographical-shaped grooves, while increasing the conduit wall thickness saw no positive effect on the biological response of the regenerating nerve. Furthermore, the preferred SL-grooved conduit (C) with 70 μm wall thickness was compared with the current clinical gold standard of autologous nerve graft (Ag) in the rat 10-mm sciatic nerve gap model. At 3 weeks postsurgery, all nerve gaps across both groups were bridged with regenerated nerve fibers. At 16 weeks, features of regenerated axons were comparable between the autograft (Ag) and conduit (C) groups. End organ assessments of muscle weight, electromyography, and skin reinnervation were also similar between the groups. The comparable experimental outcome between conduit and autograft, suggests that the PCL/PLA conduit with inner lumen microstructured grooves could be used as a potential alternative treatment for peripheral nerve repair. PMID:25435096

IncobotulinumtoxinA treatment of facial nerve palsy after neurosurgery.

PubMed

Akulov, Mihail A; Orlova, Ol'ga R; Orlova, Aleksandra S; Usachev, Dmitrij J; Shimansky, Vadim N; Tanjashin, Sergey V; Khatkova, Svetlana E; Yunosha-Shanyavskaya, Anna V

2017-10-15

This study evaluates the effect of incobotulinumtoxinA in the acute and chronic phases of facial nerve palsy after neurosurgical interventions. Patients received incobotulinumtoxinA injections (active treatment group) or standard rehabilitation treatment (control group). Functional efficacy was assessed using House-Brackmann, Yanagihara System and Sunnybrook Facial Grading scales, and Facial Disability Index self-assessment. Significant improvements on all scales were seen after 1month of incobotulinumtoxinA treatment (active treatment group, р<0.05), but only after 3months of rehabilitation treatment (control group, р<0.05). At 1 and 2years post-surgery, the prevalence of synkinesis was significantly higher in patients in the control group compared with those receiving incobotulinumtoxinA treatment (р<0.05 and р<0.001, respectively). IncobotulinumtoxinA treatment resulted in significant improvements in facial symmetry in patients with facial nerve injury following neurosurgical interventions. Treatment was effective for the correction of the compensatory hyperactivity of mimic muscles on the unaffected side that develops in the acute period of facial nerve palsy, and for the correction of synkinesis in the affected side that develops in the long-term period. Appropriate dosing and patient education to perform exercises to restore mimic muscle function should be considered in multimodal treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Influencing Factors Analysis of Facial Nerve Function after the Microsurgical Resection of Acoustic Neuroma

PubMed Central

Hong, WenMing; Cheng, HongWei; Wang, XiaoJie; Feng, ChunGuo

2017-01-01

Objective To explore and analyze the influencing factors of facial nerve function retainment after microsurgery resection of acoustic neurinoma. Methods Retrospective analysis of our hospital 105 acoustic neuroma cases from October, 2006 to January 2012, in the group all patients were treated with suboccipital sigmoid sinus approach to acoustic neuroma microsurgery resection. We adopted researching individual patient data, outpatient review and telephone followed up and the House-Brackmann grading system to evaluate and analyze the facial nerve function. Results Among 105 patients in this study group, complete surgical resection rate was 80.9% (85/105), subtotal resection rate was 14.3% (15/105), and partial resection rate 4.8% (5/105). The rate of facial nerve retainment on neuroanatomy was 95.3% (100/105) and the mortality rate was 2.1% (2/105). Facial nerve function when the patient is discharged from the hospital, also known as immediate facial nerve function which was graded in House-Brackmann: excellent facial nerve function (House-Brackmann I–II level) cases accounted for 75.2% (79/105), facial nerve function III–IV level cases accounted for 22.9% (24/105), and V–VI cases accounted for 1.9% (2/105). Patients were followed up for more than one year, with excellent facial nerve function retention rate (H-B I–II level) was 74.4% (58/78). Conclusion Acoustic neuroma patients after surgery, the long-term (≥1 year) facial nerve function excellent retaining rate was closely related with surgical proficiency, post-operative immediate facial nerve function, diameter of tumor and whether to use electrophysiological monitoring techniques; while there was no significant correlation with the patient’s age, surgical approach, whether to stripping the internal auditory canal, whether there was cystic degeneration, tumor recurrence, whether to merge with obstructive hydrocephalus and the length of the duration of symptoms. PMID:28264236

Neurophysiological mechanism of possibly confounding peripheral activation of the facial nerve during corticobulbar tract monitoring.

PubMed

Téllez, Maria J; Ulkatan, Sedat; Urriza, Javier; Arranz-Arranz, Beatriz; Deletis, Vedran

2016-02-01

To improve the recognition and possibly prevent confounding peripheral activation of the facial nerve caused by leaking transcranial electrical stimulation (TES) current during corticobulbar tract monitoring. We applied a single stimulus and a short train of electrical stimuli directly to the extracranial portion of the facial nerve. We compared the peripherally elicited compound muscle action potential (CMAP) of the facial nerve with the responses elicited by TES during intraoperative monitoring of the corticobulbar tract. A single stimulus applied directly to the facial nerve at subthreshold intensities did not evoke a CMAP, whereas short trains of subthreshold stimuli repeatedly evoked CMAPs. This is due to the phenomenon of sub- or near-threshold super excitability of the cranial nerve. Therefore, the facial responses evoked by short trains TES, when the leaked current reaches the facial nerve at sub- or near-threshold intensity, could lead to false interpretation. Our results revealed a potential pitfall in the current methodology for facial corticobulbar tract monitoring that is due to the activation of the facial nerve by subthreshold trains of stimuli. This study proposes a new criterion to exclude peripheral activation during corticobulbar tract monitoring. The failure to recognize and avoid facial nerve activation due to leaking current in the peripheral portion of the facial nerve during TES decreases the reliability of corticobulbar tract monitoring by increasing the possibility of false interpretation. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Overview of pediatric peripheral facial nerve paralysis: analysis of 40 patients.

PubMed

Özkale, Yasemin; Erol, İlknur; Saygı, Semra; Yılmaz, İsmail

2015-02-01

Peripheral facial nerve paralysis in children might be an alarming sign of serious disease such as malignancy, systemic disease, congenital anomalies, trauma, infection, middle ear surgery, and hypertension. The cases of 40 consecutive children and adolescents who were diagnosed with peripheral facial nerve paralysis at Baskent University Adana Hospital Pediatrics and Pediatric Neurology Unit between January 2010 and January 2013 were retrospectively evaluated. We determined that the most common cause was Bell palsy, followed by infection, tumor lesion, and suspected chemotherapy toxicity. We noted that younger patients had generally poorer outcome than older patients regardless of disease etiology. Peripheral facial nerve paralysis has been reported in many countries in America and Europe; however, knowledge about its clinical features, microbiology, neuroimaging, and treatment in Turkey is incomplete. The present study demonstrated that Bell palsy and infection were the most common etiologies of peripheral facial nerve paralysis. © The Author(s) 2014.

Bell's palsy and partial hypoglossal to facial nerve transfer: Case presentation and literature review

PubMed Central

Socolovsky, Mariano; Páez, Miguel Domínguez; Masi, Gilda Di; Molina, Gonzalo; Fernández, Eduardo

2012-01-01

Background: Idiopathic facial nerve palsy (Bell's palsy) is a very common condition that affects active population. Despite its generally benign course, a minority of patients can remain with permanent and severe sequelae, including facial palsy or dyskinesia. Hypoglossal to facial nerve anastomosis is rarely used to reinnervate the mimic muscle in these patients. In this paper, we present a case where a direct partial hypoglossal to facial nerve transfer was used to reinnervate the upper and lower face. We also discuss the indications of this procedure. Case Description: A 53-year-old woman presenting a spontaneous complete (House and Brackmann grade 6) facial palsy on her left side showed no improvement after 13 months of conservative treatment. Electromyography (EMG) showed complete denervation of the mimic muscles. A direct partial hypoglossal to facial nerve anastomosis was performed, including dissection of the facial nerve at the fallopian canal. One year after the procedure, the patient showed House and Brackmann grade 3 function in her affected face. Conclusions: Partial hypoglossal–facial anastomosis with intratemporal drilling of the facial nerve is a viable technique in the rare cases in which severe Bell's palsy does not recover spontaneously. Only carefully selected patients can really benefit from this technique. PMID:22574255

Our experience with facial nerve monitoring in vestibular schwannoma surgery under partial neuromuscular blockade.

PubMed

Vega-Céliz, Jorge; Amilibia-Cabeza, Emili; Prades-Martí, José; Miró-Castillo, Nuria; Pérez-Grau, Marta; Pintanel Rius, Teresa; Roca-Ribas Serdà, Francesc

2015-01-01

Facial nerve monitoring is fundamental in the preservation of the facial nerve in vestibular schwannoma surgery. Our objective was to analyse the usefulness of facial nerve monitoring under partial neuromuscular blockade. This was a retrospective analysis of 69 patients operated in a tertiary hospital. We monitored 100% of the cases. In 75% of the cases, we could measure an electromyographic response after tumour resection. In 17 cases, there was an absence of electromyographic response. Fifteen of them had an anatomic lesion with loss of continuity of the facial nerve and, in 2 cases, there was a lesion with preservation of the nerve. Preoperative facial palsy (29% 7%; P=.0349), large tumour size (88 vs. 38%; P=.0276), and a non-functional audition (88 vs. 51%; P=.0276) were significantly related with an absence of electromyographic response. Facial nerve monitoring under neuromuscular blockade is possible and safe in patients without previous facial palsy. If the patient had an electromyographic response after tumour excision, they developed better facial function in the postoperative period and after a year of follow up. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

Peripheral nerve regeneration using a microporous polylactic acid asymmetric conduit in a rabbit long-gap sciatic nerve transection model.

PubMed

Hsu, Shan-Hui; Chan, Shan-Ho; Chiang, Chih-Ming; Chen, Clayton Chi-Chang; Jiang, Ching-Fen

2011-05-01

The performance of an asymmetric conduit made of microporous polylactic acid (PLA) in promoting the long-term peripheral nerve regeneration across a 20-mm-long sciatic nerve gap was evaluated by a rabbit sciatic nerve transection model. Magnetic resonance imaging (MRI) was employed to monitor the nerve regeneration process. The extents of nerve regeneration and conduit degradation were quantified by image analysis. Functional and histological analyses were followed to assess nerve reinnervation. MR images showed that the transected nerve was connected at about 4 months. The diameter of the regenerated nerve continued to increase while the conduit was gradually degraded. The conduit was completely degraded in 18 months. The degradation kinetics in vivo was estimated based on MR images. The functional recovery after 18 months was ∼82% based on electrophysiology. The extension range of the operated limb was slowly recuperated to ∼81% at 18 months. Histology showed that nerve bundles were self-assembled after 16-18 months, but the morphologies were still different from those of normal sciatic nerve. This was the first work on the long-term evaluation of peripheral nerve regeneration in a rabbit model, and the first to report the use of MRI to obtain the real-time images of regenerated nerve in a biomaterial conduit as well as to define the degradation rate of the conduit in vivo. The platform established in this study serves to evaluate the regeneration of larger-diameter (>3-mm) nerve across a long-gap bridged by a conduit. Copyright © 2011 Elsevier Ltd. All rights reserved.

Facial nerve hemangiomas: vascular tumors or malformations?

PubMed

Benoit, Margo McKenna; North, Paula E; McKenna, Michael J; Mihm, Martin C; Johnson, Matthew M; Cunningham, Michael J

2010-01-01

To reclassify facial nerve hemangiomas in the context of presently accepted vascular lesion nomenclature by examining histology and immunohistochemical markers. Cohort analysis of patients diagnosed with a facial nerve hemangioma between 1990 and 2008. Collaborative analysis at a specialty hospital and a major academic hospital. Seven subjects were identified on composite review of office charts, a pathology database spanning both institutions, and an encrypted patient registry. Clinical data were compiled, and hematoxylin-eosin-stained specimens were reviewed. For six patients, archived pathological tissue was available for immunohistochemical evaluation of markers specific for infantile hemangioma (glucose transporter protein isoform 1 [GLUT1] and Lewis Y antigen) and for lymphatic endothelial cells (podoplanin). All patients clinically presented with slowly progressive facial weakness at a mean age of 45 years without prior symptomatology. Hemotoxylin-eosin-stained histopathological slides showed irregularly shaped, dilated lesional vessels with flattened endothelial cells, scant smooth muscle, and no internal elastic lamina. Both podoplanin staining for lymphatic endothelial cells and GLUT1 and LewisY antigen staining for infantile hemangioma endothelial cells were negative in lesional vessels in all specimens for which immunohistochemical analysis was performed. Lesions of the geniculate ganglion historically referred to as "hemangiomas" do not demonstrate clinical, histopathological, or immunohistochemical features consistent with a benign vascular tumor, but instead are consistent with venous malformation. We propose that these lesions be classified as "venous vascular malformations of the facial nerve." This nomenclature should more accurately predict clinical behavior and guide therapeutic interventions.

Facial nerve paralysis associated with temporal bone masses.

PubMed

Nishijima, Hironobu; Kondo, Kenji; Kagoya, Ryoji; Iwamura, Hitoshi; Yasuhara, Kazuo; Yamasoba, Tatsuya

2017-10-01

To investigate the clinical and electrophysiological features of facial nerve paralysis (FNP) due to benign temporal bone masses (TBMs) and elucidate its differences as compared with Bell's palsy. FNP assessed by the House-Brackmann (HB) grading system and by electroneurography (ENoG) were compared retrospectively. We reviewed 914 patient records and identified 31 patients with FNP due to benign TBMs. Moderate FNP (HB Grades II-IV) was dominant for facial nerve schwannoma (FNS) (n=15), whereas severe FNP (Grades V and VI) was dominant for cholesteatomas (n=8) and hemangiomas (n=3). The average ENoG value was 19.8% for FNS, 15.6% for cholesteatoma, and 0% for hemangioma. Analysis of the correlation between HB grade and ENoG value for FNP due to TBMs and Bell's palsy revealed that given the same ENoG value, the corresponding HB grade was better for FNS, followed by cholesteatoma, and worst in Bell's palsy. Facial nerve damage caused by benign TBMs could depend on the underlying pathology. Facial movement and ENoG values did not correlate when comparing TBMs and Bell's palsy. When the HB grade is found to be unexpectedly better than the ENoG value, TBMs should be included in the differential diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Clinical significance of quantitative analysis of facial nerve enhancement on MRI in Bell's palsy.

PubMed

Song, Mee Hyun; Kim, Jinna; Jeon, Ju Hyun; Cho, Chang Il; Yoo, Eun Hye; Lee, Won-Sang; Lee, Ho-Ki

2008-11-01

Quantitative analysis of the facial nerve on the lesion side as well as the normal side, which allowed for more accurate measurement of facial nerve enhancement in patients with facial palsy, showed statistically significant correlation with the initial severity of facial nerve inflammation, although little prognostic significance was shown. This study investigated the clinical significance of quantitative measurement of facial nerve enhancement in patients with Bell's palsy by analyzing the enhancement pattern and correlating MRI findings with initial severity of facial palsy and clinical outcome. Facial nerve enhancement was measured quantitatively by using the region of interest on pre- and postcontrast T1-weighted images in 44 patients diagnosed with Bell's palsy. The signal intensity increase on the lesion side was first compared with that of the contralateral side and then correlated with the initial degree of facial palsy and prognosis. The lesion side showed significantly higher signal intensity increase compared with the normal side in all of the segments except for the mastoid segment. Signal intensity increase at the internal auditory canal and labyrinthine segments showed correlation with the initial degree of facial palsy but no significant difference was found between different prognostic groups.

Nerve stepping stone has minimal impact in aiding regeneration across long acellular nerve allografts.

PubMed

Yan, Ying; Hunter, Daniel A; Schellhardt, Lauren; Ee, Xueping; Snyder-Warwick, Alison K; Moore, Amy M; Mackinnon, Susan E; Wood, Matthew D

2018-02-01

Acellular nerve allografts (ANAs) yield less consistent favorable outcomes compared with autografts for long gap reconstructions. We evaluated whether a hybrid ANA can improve 6-cm gap reconstruction. Rat sciatic nerve was transected and repaired with either 6-cm hybrid or control ANAs. Hybrid ANAs were generated using a 1-cm cellular isograft between 2.5-cm ANAs, whereas control ANAs had no isograft. Outcomes were assessed by graft gene and marker expression (n = 4; at 4 weeks) and motor recovery and nerve histology (n = 10; at 20 weeks). Hybrid ANAs modified graft gene and marker expression and promoted modest axon regeneration across the 6-cm defect compared with control ANA (P < 0.05), but yielded no muscle recovery. Control ANAs had no appreciable axon regeneration across the 6-cm defect. A hybrid ANA confers minimal motor recovery benefits for regeneration across long gaps. Clinically, the authors will continue to reconstruct long nerve gaps with autografts. Muscle Nerve 57: 260-267, 2018. © 2017 Wiley Periodicals, Inc.

Promoting peripheral nerve regeneration with biodegradable poly (DL-lactic acid) films

PubMed Central

Li, Ruijun; Chen, Lei; Fu, Jinling; Liu, Zhigang; Wang, Shuang; Pan, Yuehai

2015-01-01

Regeneration and repair of peripheral nerve injury has always been a major problem in the clinic. The conventional technique based on suturing the nerve ends to each other coupled with the implantation of nerve conduits outside is associated with postoperative adhesions and scar problems. Recently, a novel biodegradable poly (DL-lactic acid) (PDLLA) film has been introduced. This novel anti-adhesion film has a porous structure with better mechanical properties, better flexibility, and more controllable degradation as compared to traditional non-porous nerve conduits. However, little is known about the effects of such PDLLA films on regeneration and repair of peripheral nerve injury in vivo. In this study, we evaluated the effects of PDLLA films implantation after sciatic nerve transection and anastomosis on subsequent sciatic nerve regeneration in vivo, using a rat sciatic nerve injury model. Sciatic nerve transection surgery coupled with direct suturing only, suturing and wrapping with traditional nerve conduits, or suturing and wrapping with PDLLA films was performed on adult Wistar rats. The additional wrapping with PDLLA films inhibited the nerve adhesion after 12 weeks recovery from surgery. It also increased the compound muscle action potentials and tibialis and gastrocnemius muscle wet weight ratio following 8 weeks recovery from surgery. Regenerated nerve fibers were relatively straight and the aligned structure was complete in rats with implantations of PDLLA films. The results suggested that PDLLA films can improve the nutritional status in the muscles innervated by the damaged nerves and promote nerve regeneration in vivo. PMID:26339372

Strategies to promote peripheral nerve regeneration: electrical stimulation and/or exercise

PubMed Central

Gordon, Tessa; English, Arthur W.

2015-01-01

Enhancing the regeneration of axons is often considered a therapeutic target for improving functional recovery after peripheral nerve injury. In this review, the evidence for the efficacy of electrical stimulation (ES), daily exercise, and their combination in promoting nerve regeneration after peripheral nerve injuries in both animal models and in human patients, is explored. The rationale, effectiveness, and molecular basis of ES and exercise in accelerating axon outgrowth are reviewed. In comparing the effects of ES and exercise in enhancing axon regeneration, increased neural activity, neurotrophins, and androgens are considered common requirements. Similar, gender-specific requirements are found for exercise to enhance axon regeneration in the periphery and for sustaining synaptic inputs onto injured motoneurons. ES promotes nerve regeneration after delayed nerve repair in humans and rats. The effectiveness of exercise is less clear. Although ES, but not exercise, results in a significant misdirection of regenerating motor axons to reinnervate different muscle targets, the loss of neuromuscular specificity encountered has only a very small impact on resulting functional recovery. Both ES and exercise are promising experimental treatments for peripheral nerve injury that seem ready to be translated to clinical use. PMID:26121368

Review: peripheral nerve regeneration using non-tubular alginate gel crosslinked with covalent bonds.

PubMed

Hashimoto, Tadashi; Suzuki, Yoshihisa; Suzuki, Kyoko; Nakashima, Toshihide; Tanihara, Masao; Ide, Chizuka

2005-06-01

We have developed a nerve regeneration material consisting of alginate gel crosslinked with covalent bonds. in the first part of this study, we attempted to analyze nerve regeneration through alginate gel in the early stages within 2 weeks. in the second part, we tried to regenerate cat peripheral nerve by using alginate tubular or non-tubular nerve regeneration devices, and compared their efficacies. Four days after surgery, regenerating axons grew without Schwann cell investment through the partially degraded alginate gel, being in direct contact with the alginate without a basal lamina covering. One to 2 weeks after surgery, regenerating axons were surrounded by common Schwann cells, forming small bundles, with some axons at the periphery being partly in direct contact with alginate. At the distal stump, numerous Schwann cells had migrated into the alginate 8-14 days after surgery. Remarkable restorations of the 50-mm gap in cat sciatic nerve were obtained after a long term by using tubular or non-tubular nerve regeneration material consisting mainly of alginate gel. However, there was no significant difference between both groups at electrophysiological and morphological evaluation. Although, nowadays, nerve regeneration materials being marketed mostly have a tubular structure, our results suggest that the tubular structure is not indispensable for peripheral nerve regeneration.

A 63-year-old man with peripheral facial nerve paralysis and a pulmonary lesion.

PubMed

Yserbyt, J; Wilms, G; Lievens, Y; Nackaerts, K

2009-01-01

Occasionally, malignant neoplasms may cause peripheral facial nerve paralysis as a presenting symptom. A 63-year-old man was referred to the Emergency Department because of a peripheral facial nerve paralysis, lasting for 10 days. Initial diagnostic examinations revealed no apparent cause for this facial nerve paralysis. Chest X-ray, however, showed a suspicious tumoural mass, located in the right hilar region, as confirmed by CAT scan. The diagnosis of an advanced stage lung adenocarcinoma was finally confirmed by bronchial biopsy. MRI scanning showed diffuse brain metastases and revealed a pontine lesion as the most probable underlying cause of this case of peripheral facial nerve paralysis. Platin-based palliative chemotherapy was given, after an initial pancranial irradiation. According to the MRI findings, the pontine lesion was responsible for the peripheral facial nerve paralysis, as an initial presenting symptom in this case of lung adenocarcinoma. This clinical case of a peripheral facial nerve paralysis was caused by a pontine brain metastasis and illustrates a rather rare presenting symptom of metastatic lung cancer.

Identification of adequate vehicles to carry nerve regeneration inducers using tubulisation.

PubMed

do Nascimento-Elias, Adriana Helena; Fresnesdas, Bruno César; Schiavoni, Maria Cristina Lopes; de Almeida, Natália Fernanda Gaspar; Santos, Ana Paula; de Oliveira Ramos, Jean; Junior, Wilson Marques; Barreira, Amilton Antunes

2012-08-14

Axonal regeneration depends on many factors, such as the type of injury and repair, age, distance from the cell body and distance of the denervated muscle, loss of surrounding tissue and the type of injured nerve. Experimental models use tubulisation with a silicone tube to research regenerative factors and substances to induce regeneration. Agarose, collagen and DMEM (Dulbecco's modified Eagle's medium) can be used as vehicles. In this study, we compared the ability of these vehicles to induce rat sciatic nerve regeneration with the intent of finding the least active or inert substance. The experiment used 47 female Wistar rats, which were divided into four experimental groups (agarose 4%, agarose 0.4%, collagen, DMEM) and one normal control group. The right sciatic nerve was exposed, and an incision was made that created a 10 mm gap between the distal and proximal stumps. A silicone tube was grafted onto each stump, and the tubes were filled with the respective media. After 70 days, the sciatic nerve was removed. We evaluated the formation of a regeneration cable, nerve fibre growth, and the functional viability of the regenerated fibres. Comparison among the three vehicles showed that 0.4% agarose gels had almost no effect on provoking the regeneration of peripheral nerves and that 4% agarose gels completely prevented fibre growth. The others substances were associated with profuse nerve fibre growth. In the appropriate concentration, agarose gel may be an important vehicle for testing factors that induce regeneration without interfering with nerve growth.

Pre-differentiation of mesenchymal stromal cells in combination with a microstructured nerve guide supports peripheral nerve regeneration in the rat sciatic nerve model.

PubMed

Boecker, Arne Hendrik; van Neerven, Sabien Geraldine Antonia; Scheffel, Juliane; Tank, Julian; Altinova, Haktan; Seidensticker, Katrin; Deumens, Ronald; Tolba, Rene; Weis, Joachim; Brook, Gary Anthony; Pallua, Norbert; Bozkurt, Ahmet

2016-02-01

Many bioartificial nerve guides have been investigated pre-clinically for their nerve regeneration-supporting function, often in comparison to autologous nerve transplantation, which is still regarded as the current clinical gold standard. Enrichment of these scaffolds with cells intended to support axonal regeneration has been explored as a strategy to boost axonal regeneration across these nerve guides Ansselin et al. (1998). In the present study, 20 mm rat sciatic nerve defects were implanted with a cell-seeded microstructured collagen nerve guide (Perimaix) or an autologous nerve graft. Under the influence of seeded, pre-differentiated mesenchymal stromal cells, axons regenerated well into the Perimaix nerve guide. Myelination-related parameters, like myelin sheath thickness, benefitted from an additional seeding with pre-differentiated mesenchymal stromal cells. Furthermore, both the number of retrogradely labelled sensory neurons and the axon density within the implant were elevated in the cell-seeded scaffold group with pre-differentiated mesenchymal stromal cells. However, a pre-differentiation had no influence on functional recovery. An additional cell seeding of the Perimaix nerve guide with mesenchymal stromal cells led to an extent of functional recovery, independent of the differentiation status, similar to autologous nerve transplantation. These findings encourage further investigations on pre-differentiated mesenchymal stromal cells as a cellular support for peripheral nerve regeneration. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Valproic Acid Promotes Survival of Facial Motor Neurons in Adult Rats After Facial Nerve Transection: a Pilot Study.

PubMed

Zhang, Lili; Fan, Zhaomin; Han, Yuechen; Xu, Lei; Liu, Wenwen; Bai, Xiaohui; Zhou, Meijuan; Li, Jianfeng; Wang, Haibo

2018-04-01

Valproic acid (VPA), a medication primarily used to treat epilepsy and bipolar disorder, has been applied to the repair of central and peripheral nervous system injury. The present study investigated the effect of VPA on functional recovery, survival of facial motor neurons (FMNs), and expression of proteins in rats after facial nerve trunk transection by functional measurement, Nissl staining, TUNEL, immunofluorescence, and Western blot. Following facial nerve injury, all rats in group VPA showed a better functional recovery, which was significant at the given time, compared with group NS. The Nissl staining results demonstrated that the number of FMNs survival in group VPA was higher than that in group normal saline (NS). TUNEL staining showed that axonal injury of facial nerve could lead to neuronal apoptosis of FMNs. But treatment of VPA significantly reduced cell apoptosis by decreasing the expression of Bax protein and increased neuronal survival by upregulating the level of brain-derived neurotrophic factor (BDNF) and growth associated protein-43 (GAP-43) expression in injured FMNs compared with group NS. Overall, our findings suggest that VPA may advance functional recovery, reduce lesion-induced apoptosis, and promote neuron survival after facial nerve transection in rats. This study provides an experimental evidence for better understanding the mechanism of injury and repair of peripheral facial paralysis.

High variability of facial muscle innervation by facial nerve branches: A prospective electrostimulation study.

PubMed

Raslan, Ashraf; Volk, Gerd Fabian; Möller, Martin; Stark, Vincent; Eckhardt, Nikolas; Guntinas-Lichius, Orlando

2017-06-01

To examine by intraoperative electric stimulation which peripheral facial nerve (FN) branches are functionally connected to which facial muscle functions. Single-center prospective clinical study. Seven patients whose peripheral FN branching was exposed during parotidectomy under FN monitoring received a systematic electrostimulation of each branch starting with 0.1 mA and stepwise increase to 2 mA with a frequency of 3 Hz. The electrostimulation and the facial and neck movements were video recorded simultaneously and evaluated independently by two investigators. A uniform functional allocation of specific peripheral FN branches to a specific mimic movement was not possible. Stimulation of the whole spectrum of branches of the temporofacial division could lead to eye closure (orbicularis oculi muscle function). Stimulation of the spectrum of nerve branches of the cervicofacial division could lead to reactions in the midface (nasal and zygomatic muscles) as well as around the mouth (orbicularis oris and depressor anguli oris muscle function). Frontal and eye region were exclusively supplied by the temporofacial division. The region of the mouth and the neck was exclusively supplied by the cervicofacial division. Nose and zygomatic region were mainly supplied by the temporofacial division, but some patients had also nerve branches of the cervicofacial division functionally supplying the nasal and zygomatic region. FN branches distal to temporofacial and cervicofacial division are not necessarily covered by common facial nerve monitoring. Future bionic devices will need a patient-specific evaluation to stimulate the correct peripheral nerve branches to trigger distinct muscle functions. 4 Laryngoscope, 127:1288-1295, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Comparison of Direct Side-to-End and End-to-End Hypoglossal-Facial Anastomosis for Facial Nerve Repair.

PubMed

Samii, Madjid; Alimohamadi, Maysam; Khouzani, Reza Karimi; Rashid, Masoud Rafizadeh; Gerganov, Venelin

2015-08-01

The hypoglossal facial anastomosis (HFA) is the gold standard for facial reanimation in patients with severe facial nerve palsy. The major drawbacks of the classic HFA technique are lingual morbidities due to hypoglossal nerve transection. The side-to-end HFA is a modification of the classic technique with fewer tongue-related morbidities. In this study we compared the outcome of the classic end-to-end and the direct side-to-end HFA surgeries performed at our center in regards to the facial reanimation success rate and tongue-related morbidities. Twenty-six successive cases of HFA were enrolled. In 9 of them end-to-end anastomoses were performed, and 17 had direct side-to-end anastomoses. The House-Brackmann (HB) and Pitty and Tator (PT) scales were used to document surgical outcome. The hemiglossal atrophy, swallowing, and hypoglossal nerve function were assessed at follow-up. The original pathology was vestibular schwannoma in 15, meningioma in 4, brain stem glioma in 4, and other pathologies in 3. The mean interval between facial palsy and HFA was 18 months (range: 0-60). The median follow-up period was 20 months. The PT grade at follow-up was worse in patients with a longer interval from facial palsy and HFA (P value: 0.041). The lesion type was the only other factor that affected PT grade (the best results in vestibular schwannoma and the worst in the other pathologies group, P value: 0.038). The recovery period for facial tonicity was longer in patients with radiation therapy before HFA (13.5 vs. 8.5 months) and those with a longer than 2-year interval from facial palsy to HFA (13.5 vs. 8.5 months). Although no significant difference between the side-to-end and the end-to-end groups was seen in terms of facial nerve functional recovery, patients from the side-to-end group had a significantly lower rate of lingual morbidities (tongue hemiatrophy: 100% vs. 5.8%, swallowing difficulty: 55% vs. 11.7%, speech disorder 33% vs. 0%). With the side-to-end HFA

Regeneration of the eighth cranial nerve in the bullfrog, Rana catesbeiana.

PubMed

Newman, A; Honrubia, V

1992-01-01

The present study was done in order to document the ability of the eighth cranial nerve of the bullfrog (Rana catesbeiana) to regenerate, the anatomic characteristics of the regenerated fibers, and the specificity of projections from individual endorgan branches of the nerve. The eighth cranial nerve was sharply transected between the ganglion cells and the brain stem in 40 healthy bullfrogs and allowed to regenerate. Anatomic studies were performed in these animals a minimum of 3 months postoperatively. Horseradish peroxidase was used to label the whole vestibular nerve or its individual endorgan branches. Labeled regenerated fibers could be identified crossing the site of the nerve section and projecting centrally to the vestibular nuclei in a pattern similar to that of normal frogs. Labeling of individual branches showed that regenerated fibers innervated the same specific areas found in normal frogs. Unlike normal animals, both thick and thin fibers projected to the medial nucleus.

Facial reanimation with masseteric nerve: babysitter or permanent procedure? Preliminary results.

PubMed

Faria, Jose Carlos Marques; Scopel, Gean Paulo; Ferreira, Marcus Castro

2010-01-01

The authors are presenting a series of 10 cases of complete unilateral facial paralysis submitted to (I) end-to-end microsurgical coaptation of the masseteric branch of the trigeminal nerve and distal branches of the paralyzed facial nerve, and (II) cross-face sural nerve graft. The ages of the patients ranged from 5 to 63 years (mean: 44.1 years), and 8 (80%) of the patients were females. The duration of paralysis was no longer than 18 months (mean: 9.7 months). Follow-up varied from 6 to 18 months (mean: 12.6 months). Initial voluntary facial movements were observed between 3 and 6 months postoperatively (mean: 4.3 months). All patients were able to produce the appearance of a smile when asked to clench their teeth. Comparing the definition of the nasolabial fold and the degree of movement of the modiolus on both sides of the face, the voluntary smile was considered symmetrical in 8 cases. Recovery of the capacity to blink spontaneously was not observed. However, 8 patients were able to reduce or suspend the application of artificial tears. The authors suggest consideration of masseteric-facial nerve coaptation, whether temporary (baby-sitter) or permanent, as the principal alternative for reconstruction of facial paralysis due to irreversible nerve lesion with less than 18 months of duration.

Clinical features and management of facial nerve paralysis in children: analysis of 24 cases.

PubMed

Cha, H E; Baek, M K; Yoon, J H; Yoon, B K; Kim, M J; Lee, J H

2010-04-01

To evaluate the causes, treatment modalities and recovery rate of paediatric facial nerve paralysis. We analysed 24 cases of paediatric facial nerve paralysis diagnosed in the otolaryngology department of Gachon University Gil Medical Center between January 2001 and June 2006. The most common cause was idiopathic palsy (16 cases, 66.7 per cent). The most common degree of facial nerve paralysis on first presentation was House-Brackmann grade IV (15 of 24 cases). All cases were treated with steroids. One of the 24 cases was also treated surgically with facial nerve decompression. Twenty-two cases (91.6 per cent) recovered to House-Brackmann grade I or II over the six-month follow-up period. Facial nerve paralysis in children can generally be successfully treated with conservative measures. However, in cases associated with trauma, radiological investigation is required for further evaluation and treatment.

Isolated marginal facial nerve paresis after TMJ discopexy: a case report.

PubMed

Reychler, H; Mahy, P

2011-01-01

Isolated marginal facial nerve paresis after TMJ discopexy: a case report. This is the first report of a transient, isolated marginal facial nerve paresis after temporomandibular joint arthrotomy. The paresis seems to have resulted from a crush lesion by Backhaus forceps, placed transcutaneously during the operation to distract the intra-articular space.

The split hypoglossal nerve versus the cross-face nerve graft to supply the free functional muscle transfer for facial reanimation: A comparative study.

PubMed

Amer, Tarek A; El Kholy, Mohamed S

2018-05-01

Long-standing cases of facial paralysis are currently treated with free functional muscle transfer. Several nerves are mentioned in the literature to supply the free muscle transfer. The aim of this study is to compare the split hypoglossal nerve and the cross-face nerve graft to supply the free functional muscle transfer in facial reanimation. Of 94 patients with long-standing, unilateral facial palsy, 49 were treated using the latissimus dorsi muscle supplied by the split hypoglossal nerve, and 45 patients were treated using the latissmus dorsi muscle supplied by healthy contralateral buccal branch of the facial nerve. The excursion gained by the free muscle transfer supplied by the split hypoglossal nerve (mean 19.20 ± 6.321) was significantly higher (P value 0.001) than that obtained by the contralateral buccal branch of the facial nerve (mean 14.59 ± 6.245). The split hypoglossal nerve appears to be a good possible option to supply the free vascularised muscle transfer in facial reanimation. It yields a stronger excursion in less time than the contralateral cross-face nerve graft. Copyright © 2018 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, Lei; Liu, Yi; Zhao, Hua

Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediatedmore » transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which

[Motor nerves of the face. Surgical and radiologic anatomy of facial paralysis and their surgical repair].

PubMed

Vacher, C; Cyna-Gorse, F

2015-10-01

Motor innervation of the face depends on the facial nerve for the mobility of the face, on the mandibular nerve, third branch of the trigeminal nerve, which gives the motor innervation of the masticator muscles, and the hypoglossal nerve for the tongue. In case of facial paralysis, the most common palliative surgical techniques are the lengthening temporalis myoplasty (the temporal is innervated by the mandibular nerve) and the hypoglossal-facial anastomosis. The aim of this work is to describe the surgical anatomy of these three nerves and the radiologic anatomy of the facial nerve inside the temporal bone. Then the facial nerve penetrates inside the parotid gland giving a plexus. Four branches of the facial nerve leave the parotid gland: they are called temporal, zygomatic, buccal and marginal which give innervation to the cutaneous muscles of the face. Mandibular nerve gives three branches to the temporal muscles: the anterior, intermediate and posterior deep temporal nerves which penetrate inside the deep aspect of the temporal muscle in front of the infratemporal line. The hypoglossal nerve is only the motor nerve to the tongue. The ansa cervicalis, which is coming from the superficial cervical plexus and joins the hypoglossal nerve in the submandibular area is giving the motor innervation to subhyoid muscles and to the geniohyoid muscle. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Nerve regeneration with aid of nanotechnology and cellular engineering.

PubMed

Sedaghati, Tina; Yang, Shi Yu; Mosahebi, Afshin; Alavijeh, Mohammad S; Seifalian, Alexander M

2011-01-01

Repairing nerve defects with large gaps remains one of the most operative challenges for surgeons. Incomplete recovery from peripheral nerve injuries can produce a diversity of negative outcomes, including numbness, impairment of sensory or motor function, possibility of developing chronic pain, and devastating permanent disability. In the last few years, numerous microsurgical techniques, such as coaptation, nerve autograft, and different biological or polymeric nerve conduits, have been developed to reconstruct a long segment of damaged peripheral nerve. A few of these techniques are promising and have become popular among surgeons. Advancements in the field of tissue engineering have led to development of synthetic nerve conduits as an alternative for the nerve autograft technique, which is the current practice to bridge nerve defects with gaps larger than 30 mm. However, to date, despite significant progress in this field, no material has been found to be an ideal alternative to the nerve autograft. This article briefly reviews major up-to-date published studies using different materials as an alternative to the nerve autograft to bridge peripheral nerve gaps in an attempt to assess their ability to support and enhance nerve regeneration and their prospective drawbacks, and also highlights the promising hope for nerve regeneration with the next generation of nerve conduits, which has been significantly enhanced with the tissue engineering approach, especially with the aid of nanotechnology in development of the three-dimensional scaffold. The goal is to determine potential alternatives for nerve regeneration and repair that are simply and directly applicable in clinical conditions. Copyright © 2011 International Union of Biochemistry and Molecular Biology, Inc.

Length of nerve gap defects correlates with incidence of nerve regeneration but not with recovery of taste function in patients with severed chorda tympani nerve.

PubMed

Saito, Takehisa; Narita, Norihiko; Yamada, Takechiyo; Ogi, Kazuhiro; Kanno, Masafumi; Manabe, Yasuhiro; Ito, Tetsufumi

2011-10-01

To evaluate the relationship between the length of nerve gap defects, incidence of nerve regeneration, and recovery of gustatory function after severing the chorda tympani nerve (CTN). Retrospective study. University hospital. Eighty-eight consecutive patients whose CTNs were severed during primary surgery and who underwent secondary surgery were included. Proximal and distal stumps of severed nerves were readapted or approximated during surgery. Therapeutic. Before and after surgery, the taste function was periodically evaluated using electrogustometry. Nerve gaps were classified into 4 groups: readaptation (Group 1), 1 to 3 mm (Group 2), 4 to 6 mm (Group 3), and more than 7 mm (Group 4). Regenerated nerves in the tympanic segment were detected in 36 (41%) of the 88 patients during secondary surgery. The incidence of nerve regeneration was 100% (10/10) in Group 1, 45% (10/22) in Group 2, 47% (9/19) in Group 3, and 19% (7/37) in Group 4. There was a significant difference between the length of nerve gap defects and incidence of nerve regeneration (p < 0.001). In the 36 patients with a regenerated CTN, the incidence of gustatory function recovery was 60% (6/10) in Group 1, 50% (5/10) in Group 2, 56% (5/9) in Group 3, and 43% (3/7) in Group 4. There was no significant difference between the length of nerve gap defects and incidence of taste function recovery. Reconstruction of a severed CTN is very important for regeneration. However, the regenerated CTN in the tympanic segment does not always reinnervate the fungiform papillae.

Intraoperative identification of the facial nerve by needle electromyography stimulation with a burr

PubMed Central

KHAMGUSHKEEVA, N.N.; ANIKIN, I.A.; KORNEYENKOV, A.A.

2016-01-01

The purpose of this research is to improve the safety of surgery for patients with a pathology of the middle and inner ear by preventing damage to the facial nerve by conducting intraoperative monitoring of the facial nerve by needle electromyography with continuous stimulation with a burr. Patients and Methods The clinical part of the prospective study was carried out on 48 patients that were diagnosed with suppurative otitis media. After the surgery with intraoperative monitoring, the facial nerve with an intact bone wall was stimulated electrically in the potentially dangerous places of damage. Minimum (threshold) stimulation (mA) of the facial nerve with a threshold event of 100 μV was used to register EMG events. The anatomical part of the study was carried out on 30 unformalinized cadaver temporal bones from adult bodies. The statistical analysis of obtained data was carried out with parametric methods (Student’s t-test), non-parametric correlation (Spearman’s method) and regression analysis. Results It was found that 1 mA of threshold amperage corresponded to 0.8 mm thickness of the bone wall of the facial canal. Values of transosseous threshold stimulation in potentially dangerous sections of the injury to the facial nerve were obtained. Conclusion These data lower the risk of paresis (paralysis) of the facial muscles during otologic surgery. PMID:27142821

A Novel Internal Fixator Device for Peripheral Nerve Regeneration

PubMed Central

Chuang, Ting-Hsien; Wilson, Robin E.; Love, James M.; Fisher, John P.

2013-01-01

Recovery from peripheral nerve damage, especially for a transected nerve, is rarely complete, resulting in impaired motor function, sensory loss, and chronic pain with inappropriate autonomic responses that seriously impair quality of life. In consequence, strategies for enhancing peripheral nerve repair are of high clinical importance. Tension is a key determinant of neuronal growth and function. In vitro and in vivo experiments have shown that moderate levels of imposed tension (strain) can encourage axonal outgrowth; however, few strategies of peripheral nerve repair emphasize the mechanical environment of the injured nerve. Toward the development of more effective nerve regeneration strategies, we demonstrate the design, fabrication, and implementation of a novel, modular nerve-lengthening device, which allows the imposition of moderate tensile loads in parallel with existing scaffold-based tissue engineering strategies for nerve repair. This concept would enable nerve regeneration in two superposed regimes of nerve extension—traditional extension through axonal outgrowth into a scaffold and extension in intact regions of the proximal nerve, such as that occurring during growth or limb-lengthening. Self-sizing silicone nerve cuffs were fabricated to grip nerve stumps without slippage, and nerves were deformed by actuating a telescoping internal fixator. Poly(lactic co-glycolic) acid (PLGA) constructs mounted on the telescoping rods were apposed to the nerve stumps to guide axonal outgrowth. Neuronal cells were exposed to PLGA using direct contact and extract methods, and they exhibited no signs of cytotoxic effects in terms of cell morphology and viability. We confirmed the feasibility of implanting and actuating our device within a sciatic nerve gap and observed axonal outgrowth following device implantation. The successful fabrication and implementation of our device provides a novel method for examining mechanical influences on nerve regeneration. PMID

Comparison of hemihypoglossal-facial nerve transposition with a cross-facial nerve graft and muscle transplant for the rehabilitation of facial paralysis using the facial clima method.

PubMed

Hontanilla, Bernardo; Vila, Antonio

2012-02-01

To compare quantitatively the results obtained after hemihypoglossal nerve transposition and microvascular gracilis transfer associated with a cross facial nerve graft (CFNG) for reanimation of a paralysed face, 66 patients underwent hemihypoglossal transposition (n = 25) or microvascular gracilis transfer and CFNG (n = 41). The commissural displacement (CD) and commissural contraction velocity (CCV) in the two groups were compared using the system known as Facial clima. There was no inter-group variability between the groups (p > 0.10) in either variable. However, intra-group variability was detected between the affected and healthy side in the transposition group (p = 0.036 and p = 0.017, respectively). The transfer group had greater symmetry in displacement of the commissure (CD) and commissural contraction velocity (CCV) than the transposition group and patients were more satisfied. However, the transposition group had correct symmetry at rest but more asymmetry of CCV and CD when smiling.

Impaired peripheral nerve regeneration in type-2 diabetic mouse model.

PubMed

Pham, Vuong M; Tu, Nguyen Huu; Katano, Tayo; Matsumura, Shinji; Saito, Akira; Yamada, Akihiro; Furue, Hidemasa; Ito, Seiji

2018-01-01

Peripheral neuropathy is one of the most common and serious complications of type-2 diabetes. Diabetic neuropathy is characterized by a distal symmetrical sensorimotor polyneuropathy, and its incidence increases in patients 40 years of age or older. In spite of extensive research over decades, there are few effective treatments for diabetic neuropathy besides glucose control and improved lifestyle. The earliest changes in diabetic neuropathy occur in sensory nerve fibers, with initial degeneration and regeneration resulting in pain. To seek its effective treatment, here we prepared a type-2 diabetic mouse model by giving mice 2 injections of streptozotocin and nicotinamide and examining the ability for nerve regeneration by using a sciatic nerve transection-regeneration model previously established by us. Seventeen weeks after the last injection, the mice exhibited symptoms of type-2 diabetes, that is, impaired glucose tolerance, decreased insulin level, mechanical hyperalgesia, and impaired sensory nerve fibers in the plantar skin. These mice showed delayed functional recovery and nerve regeneration by 2 weeks compared with young healthy mice and by 1 week compared with age-matched non-diabetic mice after axotomy. Furthermore, type-2 diabetic mice displayed increased expression of PTEN in their DRG neurons. Administration of a PTEN inhibitor at the cutting site of the nerve for 4 weeks promoted the axonal transport and functional recovery remarkably. This study demonstrates that peripheral nerve regeneration was impaired in type-2 diabetic model and that its combination with sciatic nerve transection is suitable for the study of the pathogenesis and treatment of early diabetic neuropathy. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Enhancement pattern of the normal facial nerve at 3.0 T temporal MRI.

PubMed

Hong, H S; Yi, B-H; Cha, J-G; Park, S-J; Kim, D H; Lee, H K; Lee, J-D

2010-02-01

The purpose of this study was to evaluate the enhancement pattern of the normal facial nerve at 3.0 T temporal MRI. We reviewed the medical records of 20 patients and evaluated 40 clinically normal facial nerves demonstrated by 3.0 T temporal MRI. The grade of enhancement of the facial nerve was visually scaled from 0 to 3. The patients comprised 11 men and 9 women, and the mean age was 39.7 years. The reasons for the MRI were sudden hearing loss (11 patients), Méniàre's disease (6) and tinnitus (7). Temporal MR scans were obtained by fluid-attenuated inversion-recovery (FLAIR) and diffusion-weighted imaging of the brain; three-dimensional (3D) fast imaging employing steady-state acquisition (FIESTA) images of the temporal bone with a 0.77 mm thickness, and pre-contrast and contrast-enhanced 3D spoiled gradient record acquisition in the steady state (SPGR) of the temporal bone with a 1 mm thickness, were obtained with 3.0 T MR scanning. 40 nerves (100%) were visibly enhanced along at least one segment of the facial nerve. The enhanced segments included the geniculate ganglion (77.5%), tympanic segment (37.5%) and mastoid segment (100%). Even the facial nerve in the internal auditory canal (15%) and labyrinthine segments (5%) showed mild enhancement. The use of high-resolution, high signal-to-noise ratio (with 3 T MRI), thin-section contrast-enhanced 3D SPGR sequences showed enhancement of the normal facial nerve along the whole course of the nerve; however, only mild enhancement was observed in areas associated with acute neuritis, namely the canalicular and labyrinthine segment.

Chitosan-film enhanced chitosan nerve guides for long-distance regeneration of peripheral nerves.

PubMed

Meyer, Cora; Stenberg, Lena; Gonzalez-Perez, Francisco; Wrobel, Sandra; Ronchi, Giulia; Udina, Esther; Suganuma, Seigo; Geuna, Stefano; Navarro, Xavier; Dahlin, Lars B; Grothe, Claudia; Haastert-Talini, Kirsten

2016-01-01

Biosynthetic nerve grafts are developed in order to complement or replace autologous nerve grafts for peripheral nerve reconstruction. Artificial nerve guides currently approved for clinical use are not widely applied in reconstructive surgery as they still have limitations especially when it comes to critical distance repair. Here we report a comprehensive analysis of fine-tuned chitosan nerve guides (CNGs) enhanced by introduction of a longitudinal chitosan film to reconstruct critical length 15 mm sciatic nerve defects in adult healthy Wistar or diabetic Goto-Kakizaki rats. Short and long term investigations demonstrated that the CNGs enhanced by the guiding structure of the introduced chitosan film significantly improved functional and morphological results of nerve regeneration in comparison to simple hollow CNGs. Importantly, this was detectable both in healthy and in diabetic rats (short term) and the regeneration outcome almost reached the outcome after autologous nerve grafting (long term). Hollow CNGs provide properties likely leading to a wider clinical acceptance than other artificial nerve guides and their performance can be increased by simple introduction of a chitosan film with the same advantageous properties. Therefore, the chitosan film enhanced CNGs represent a new generation medical device for peripheral nerve reconstruction. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Facial nerve palsy: analysis of cases reported in children in a suburban hospital in Nigeria.

PubMed

Folayan, M O; Arobieke, R I; Eziyi, E; Oyetola, E O; Elusiyan, J

2014-01-01

The study describes the epidemiology, treatment, and treatment outcomes of the 10 cases of facial nerve palsy seen in children managed at the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife over a 10 year period. It also compares findings with report from developed countries. This was a retrospective cohort review of pediatric cases of facial nerve palsy encountered in all the clinics run by specialists in the above named hospital. A diagnosis of facial palsy was based on International Classification of Diseases, Ninth Revision, Clinical Modification codes. Information retrieved from the case note included sex, age, number of days with lesion prior to presentation in the clinic, diagnosis, treatment, treatment outcome, and referral clinic. Only 10 cases of facial nerve palsy were diagnosed in the institution during the study period. Prevalence of facial nerve palsy in this hospital was 0.01%. The lesion more commonly affected males and the right side of the face. All cases were associated with infections: Mainly mumps (70% of cases). Case management include the use of steroids and eye pads for cases that presented within 7 days; and steroids, eye pad, and physical therapy for cases that presented later. All cases of facial nerve palsy associated with mumps and malaria infection fully recovered. The two cases of facial nerve palsy associated with otitis media only partially recovered. Facial nerve palsy in pediatric patients is more commonly associated with mumps in the study environment. Successes are recorded with steroid therapy.

BDNF is required for taste axon regeneration following unilateral chorda tympani nerve section.

PubMed

Meng, Lingbin; Huang, Tao; Sun, Chengsan; Hill, David L; Krimm, Robin

2017-07-01

Taste nerves readily regenerate to reinnervate denervated taste buds; however, factors required for regeneration have not yet been identified. When the chorda tympani nerve is sectioned, expression of brain-derived neurotrophic factor (BDNF) remains high in the geniculate ganglion and lingual epithelium, despite the loss of taste buds. These observations suggest that BDNF is present in the taste system after nerve section and may support taste nerve regeneration. To test this hypothesis, we inducibly deleted Bdnf during adulthood in mice. Shortly after Bdnf gene recombination, the chorda tympani nerve was unilaterally sectioned causing a loss of both taste buds and neurons, irrespective of BDNF levels. Eight weeks after nerve section, however, regeneration was differentially affected by Bdnf deletion. In control mice, there was regeneration of the chorda tympani nerve and taste buds reappeared with innervation. In contrast, few taste buds were reinnervated in mice lacking normal Bdnf expression such that taste bud number remained low. In all genotypes, taste buds that were reinnervated were normal-sized, but non-innervated taste buds remained small and atrophic. On the side of the tongue contralateral to the nerve section, taste buds for some genotypes became larger and all taste buds remained innervated. Our findings suggest that BDNF is required for nerve regeneration following gustatory nerve section. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnostic relevance of transcranial magnetic and electric stimulation of the facial nerve in the management of facial palsy.

PubMed

Nowak, Dennis A; Linder, Stefan; Topka, Helge

2005-09-01

Earlier investigations have suggested that isolated conduction block of the facial nerve to transcranial magnetic stimulation early in the disorder represents a very sensitive and potentially specific finding in Bell's palsy differentiating the disease from other etiologies. Stimulation of the facial nerve was performed electrically at the stylomastoid foramen and magnetically at the labyrinthine segment of the Fallopian channel within 3 days from symptom onset in 65 patients with Bell's palsy, five patients with Zoster oticus, one patient with neuroborreliosis and one patient with nuclear facial nerve palsy due to multiple sclerosis. Absence or decreased amplitudes of muscle responses to early transcranial magnetic stimulation was not specific for Bell's palsy, but also evident in all cases of Zoster oticus and in the case of neuroborreliosis. Amplitudes of electrically evoked muscle responses were more markedly reduced in Zoster oticus as compared to Bell's palsy, most likely due to a more severe degree of axonal degeneration. The degree of amplitude reduction of the muscle response to electrical stimulation reliably correlated with the severity of facial palsy. Transcranial magnetic stimulation in the early diagnosis of Bell's palsy is less specific than previously thought. While not specific with respect to the etiology of facial palsy, transcranial magnetic stimulation seems capable of localizing the site of lesion within the Fallopian channel. Combined with transcranial magnetic stimulation, early electrical stimulation of the facial nerve at the stylomastoid foramen may help to establish correct diagnosis and prognosis.

Magnesium supplement promotes sciatic nerve regeneration and down-regulates inflammatory response.

PubMed

Pan, Hung-Chuan; Sheu, Meei-Ling; Su, Hong-Lin; Chen, Ying-Ju; Chen, Chun-Jung; Yang, Dar-Yu; Chiu, Wen-Ta; Cheng, Fu-Chou

2011-06-01

Magnesium (Mg) supplements have been shown to significantly improve functional recovery in various neurological disorders. The essential benefits of Mg supplementation in peripheral nerve disorders have not been elucidated yet. The effect and mechanism of Mg supplementation on a sciatic nerve crush injury model was investigated. Sciatic nerve injury was induced in mice by crushing the left sciatic nerve. Mice were randomly divided into three groups with low-, basal- or high-Mg diets (corresponding to 10, 100 or 200% Mg of the basal diet). Neurobehavioral, electrophysiological and regeneration marker studies were conducted to explore nerve regeneration. First, a high Mg diet significantly increased plasma and nerve tissue Mg concentrations. In addition, Mg supplementation improved neurobehavioral, electrophysiological functions, enhanced regeneration marker, and reduced deposits of inflammatory cells as well as expression of inflammatory cytokines. Furthermore, reduced Schwann cell apoptosis was in line with the significant expression of bcl-2, bcl-X(L) and down-regulated expression of active caspase-3 and cytochrome C. In summary, improved neurological function recovery and enhanced nerve regeneration were found in mice with a sciatic nerve injury that were fed a high- Mg diet, and Schwann cells may have been rescued from apoptosis by the suppression of inflammatory responses.

Deficiency in Monocarboxylate Transporter 1 (MCT1) in Mice Delays Regeneration of Peripheral Nerves following Sciatic Nerve Crush

PubMed Central

Morrison, Brett M.; Tsingalia, Akivaga; Vidensky, Svetlana; Lee, Youngjin; Jin, Lin; Farah, Mohamed H.; Lengacher, Sylvain; Magistretti, Pierre J.; Pellerin, Luc; Rothstein, Jeffrey D.

2014-01-01

Peripheral nerve regeneration following injury occurs spontaneously, but many of the processes require metabolic energy. The mechanism of energy supply to axons has not previously been determined. In the central nervous system, monocarboxylate transporter 1 (MCT1), expressed in oligodendroglia, is critical for supplying lactate or other energy metabolites to axons. In the current study, MCT1 is shown to localize within the peripheral nervous system to perineurial cells, dorsal root ganglion neurons, and Schwann cells by MCT1 immunofluorescence and MCT1 tdTomato BAC reporter mice. To investigate whether MCT1 is necessary for peripheral nerve regeneration, sciatic nerves in MCT1 heterozygous null mice are crushed and peripheral nerve regeneration quantified electrophysiologically and anatomically. Compound muscle action potential (CMAP) recovery is delayed from a median of 21 days in wild-type mice to greater than 38 days in MCT1 heterozygote null mice. In fact, half of the MCT1 heterozygote null mice have no recovery of CMAP at 42 days, while all of the wild-type mice recovered. In addition, muscle fibers remain 40% more atrophic and neuromuscular junctions 40% more denervated at 42 days post-crush in the MCT1 heterozygote null mice than wild-type mice. The delay in nerve regeneration is not only in motor axons, as the number of regenerated axons in the sural sensory nerve of MCT1 heterozygote null mice at 4 weeks and tibial mixed sensory and motor nerve at 3 weeks is also significantly reduced compared to wild-type mice. This delay in regeneration may be partly through failed Schwann cell function, as there is reduced early phagocytosis of myelin debris and remyelination of axon segments. These data for the first time demonstrate that MCT1 is critical for regeneration of both sensory and motor axons in mice following sciatic nerve crush. PMID:25447940

[Facial nerve injuries cause changes in central nervous system microglial cells].

PubMed

Cerón, Jeimmy; Troncoso, Julieta

2016-12-01

Our research group has described both morphological and electrophysiological changes in motor cortex pyramidal neurons associated with contralateral facial nerve injury in rats. However, little is known about those neural changes, which occur together with changes in surrounding glial cells. To characterize the effect of the unilateral facial nerve injury on microglial proliferation and activation in the primary motor cortex. We performed immunohistochemical experiments in order to detect microglial cells in brain tissue of rats with unilateral facial nerve lesion sacrificed at different times after the injury. We caused two types of lesions: reversible (by crushing, which allows functional recovery), and irreversible (by section, which produces permanent paralysis). We compared the brain tissues of control animals (without surgical intervention) and sham-operated animals with animals with lesions sacrificed at 1, 3, 7, 21 or 35 days after the injury. In primary motor cortex, the microglial cells of irreversibly injured animals showed proliferation and activation between three and seven days post-lesion. The proliferation of microglial cells in reversibly injured animals was significant only three days after the lesion. Facial nerve injury causes changes in microglial cells in the primary motor cortex. These modifications could be involved in the generation of morphological and electrophysiological changes previously described in the pyramidal neurons of primary motor cortex that command facial movements.

Peripheral nerve regeneration with conduits: use of vein tubes

PubMed Central

Sabongi, Rodrigo Guerra; Fernandes, Marcela; dos Santos, João Baptista Gomes

2015-01-01

Treatment of peripheral nerve injuries remains a challenge to modern medicine due to the complexity of the neurobiological nerve regenerating process. There is a greater challenge when the transected nerve ends are not amenable to primary end-to-end tensionless neurorraphy. When facing a segmental nerve defect, great effort has been made to develop an alternative to the autologous nerve graft in order to circumvent morbidity at donor site, such as neuroma formation, scarring and permanent loss of function. Tubolization techniques have been developed to bridge nerve gaps and have been extensively studied in numerous experimental and clinical trials. The use of a conduit intends to act as a vehicle for moderation and modulation of the cellular and molecular ambience for nerve regeneration. Among several conduits, vein tubes were validated for clinical application with improving outcomes over the years. This article aims to address the investigation and treatment of segmental nerve injury and draw the current panorama on the use of vein tubes as an autogenous nerve conduit. PMID:26170802

Peripheral nerve regeneration with conduits: use of vein tubes.

PubMed

Sabongi, Rodrigo Guerra; Fernandes, Marcela; Dos Santos, João Baptista Gomes

2015-04-01

Treatment of peripheral nerve injuries remains a challenge to modern medicine due to the complexity of the neurobiological nerve regenerating process. There is a greater challenge when the transected nerve ends are not amenable to primary end-to-end tensionless neurorraphy. When facing a segmental nerve defect, great effort has been made to develop an alternative to the autologous nerve graft in order to circumvent morbidity at donor site, such as neuroma formation, scarring and permanent loss of function. Tubolization techniques have been developed to bridge nerve gaps and have been extensively studied in numerous experimental and clinical trials. The use of a conduit intends to act as a vehicle for moderation and modulation of the cellular and molecular ambience for nerve regeneration. Among several conduits, vein tubes were validated for clinical application with improving outcomes over the years. This article aims to address the investigation and treatment of segmental nerve injury and draw the current panorama on the use of vein tubes as an autogenous nerve conduit.

A multiparametric assay for quantitative nerve regeneration evaluation.

PubMed

Weyn, B; van Remoortere, M; Nuydens, R; Meert, T; van de Wouwer, G

2005-08-01

We introduce an assay for the semi-automated quantification of nerve regeneration by image analysis. Digital images of histological sections of regenerated nerves are recorded using an automated inverted microscope and merged into high-resolution mosaic images representing the entire nerve. These are analysed by a dedicated image-processing package that computes nerve-specific features (e.g. nerve area, fibre count, myelinated area) and fibre-specific features (area, perimeter, myelin sheet thickness). The assay's performance and correlation of the automatically computed data with visually obtained data are determined on a set of 140 semithin sections from the distal part of a rat tibial nerve from four different experimental treatment groups (control, sham, sutured, cut) taken at seven different time points after surgery. Results show a high correlation between the manually and automatically derived data, and a high discriminative power towards treatment. Extra value is added by the large feature set. In conclusion, the assay is fast and offers data that currently can be obtained only by a combination of laborious and time-consuming tests.

[Correlation between facial nerve functional evaluation and efficacy evaluation of acupuncture treatment for Bell's palsy].

PubMed

Zhou, Zhang-ling; Li, Cheng-xin; Jiang, Yue-bo; Zuo, Cong; Cai, Yun; Wang, Rui

2012-09-01

To assess and grade facial nerve dysfunction according to the extent of facial paralysis in the clinical course of acupuncture treatment for Bell's palsy, and to observe the interrelationship between the grade, the efficacy and the period of treatment, as well as the effect on prognosis. The authors employed the House-Brackmann scale, a commonly used evaluation scale for facial paralysis motor function, and set standards for eye fissure and lips. According to the improved scale, the authors assessed and graded the degree of facial paralysis in terms of facial nerve dysfunction both before and after treatment. The grade was divided into five levels: mild, moderate, moderately severe, severe dysfunction and complete paralysis. The authors gave acupuncture treatment according to the state of the disease without artificially setting the treatment period. The observation was focused on the efficacy and the efficacy was evaluated throughout the entire treatment process. Fifty-three cases out of 68 patients with Bell's palsy were cured and the overall rate of efficacy was 97%. Statistically significant differences (P<0.01) were perceived among the efficacy of five levels of facial nerve dysfunction. Efficacy was correlated with the damage level of the disease (correlation coefficient r=0.423, P<0.01). The course of treatment also extended with the severity of facial nerve dysfunction (P<0.01). Differences exist in patients with Bell's palsy in terms of severity of facial nerve dysfunction. Efficacy is reduced in correlation with an increase in facial nerve dysfunction, and the period of treatment varies in need of different levels of facial nerve dysfunction. It is highly necessary to assess and grade patients before observation and treatment in clinical study, and choose corresponding treatment according to severity of damage of the disease.

[CT study on the development of facial nerve canal in children].

PubMed

Li, J M; Xu, W B; Zhong, J W; Wu, H Y; Dai, W C

2016-10-07

Objective: To assess the characteristics of facial nerve canal between normal anatomy and dysplasia of children in different ages. Methods: A total of 492 health ears were divided into six groups, neonatal group (<1 m , n =42), infancy group(1 m-1 y, n =106), toddler group(1-3 y, n =102), preschool group (3-6 y, n =100), school group(6-10 y, n =60)and adolescent group (10-14 y, n =82). The length and diameter of facial nerve canal and that angles of first and second genu were measured with CT in each group. Results: ①The lengths of facial nerve canal in neonatal and infancy group were shorter than other four groups, especially in the mastoid segments of facial nerve canal. The lengths of mastoid segments in neonatal, infancy, toddler, preschool, school and adolescent groups were 5.03±0.84, 6.25±1.40, 8.34±1.38, 9.70±1.34, 10.84±1.41 and 12.17±1.83 mm, with P <0.05, respectively. After school age, the lengths of labyrinthine and tympanic segment grew slowly or developed completely ( P >0.05). ② The diameter of labyrinth and tympanic segment in neonatal group were narrower than other five groups ( P <0.05), but no significant difference among them in other groups ( P >0.05). ③The dysplasia of facial nerve canal were occurred on 978 locations. Among them, the percentage of dehiscence, aberrance, partially expanding and bifurcation were 72.9%(713/978), 5.1%(50/978), 18.9%(185/978) and 3.1%(30/978) respectively. The percentage of dehiscence in geniculate fossa segment was decreased significantly with age (neonatal group 85.7%(36/42), infancy group 59.4%(63/106), toddler group 39.2%(40/102), preschool group 33%(33/100), school group 30%(18/60)and adolescent group 26.8%(22/82), with P <0.05). Except the dehiscence of geniculate fossa and mastoid segment, there was no significant difference in the occurrence rate of the other variants ( P >O.05). Conclusions: The growth of length and dehiscence in labyrinth segment of facial nerve canal are significant in

Enhanced peripheral nerve regeneration through asymmetrically porous nerve guide conduit with nerve growth factor gradient.

PubMed

Oh, Se Heang; Kang, Jun Goo; Kim, Tae Ho; Namgung, Uk; Song, Kyu Sang; Jeon, Byeong Hwa; Lee, Jin Ho

2018-01-01

In this study, we fabricated a nerve guide conduit (NGC) with nerve growth factor (NGF) gradient along the longitudinal direction by rolling a porous polycaprolactone membrane with NGF concentration gradient. The NGF immobilized on the membrane was continuously released for up to 35 days, and the released amount of the NGF from the membrane gradually increased from the proximal to distal NGF ends, which may allow a neurotrophic factor gradient in the tubular NGC for a sufficient period. From the in vitro cell culture experiment, it was observed that the PC12 cells sense the NGF concentration gradient on the membrane for the cell proliferation and differentiation. From the in vivo animal experiment using a long gap (20 mm) sciatic nerve defect model of rats, the NGC with NGF concentration gradient allowed more rapid nerve regeneration through the NGC than the NGC itself and NGC immobilized with uniformly distributed NGF. The NGC with NGF concentration gradient seems to be a promising strategy for the peripheral nerve regeneration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 52-64, 2018. © 2017 Wiley Periodicals, Inc.

Non-invasive stimulation of the vibrissal pad improves recovery of whisking function after simultaneous lesion of the facial and infraorbital nerves in rats.

PubMed

Bendella, H; Pavlov, S P; Grosheva, M; Irintchev, A; Angelova, S K; Merkel, D; Sinis, N; Kaidoglou, K; Skouras, E; Dunlop, S A; Angelov, Doychin N

2011-07-01

We have recently shown that manual stimulation of target muscles promotes functional recovery after transection and surgical repair to pure motor nerves (facial: whisking and blink reflex; hypoglossal: tongue position). However, following facial nerve repair, manual stimulation is detrimental if sensory afferent input is eliminated by, e.g., infraorbital nerve extirpation. To further understand the interplay between sensory input and motor recovery, we performed simultaneous cut-and-suture lesions on both the facial and the infraorbital nerves and examined whether stimulation of the sensory afferents from the vibrissae by a forced use would improve motor recovery. The efficacy of 3 treatment paradigms was assessed: removal of the contralateral vibrissae to ensure a maximal use of the ipsilateral ones (vibrissal stimulation; Group 2), manual stimulation of the ipsilateral vibrissal muscles (Group 3), and vibrissal stimulation followed by manual stimulation (Group 4). Data were compared to controls which underwent surgery but did not receive any treatment (Group 1). Four months after surgery, all three treatments significantly improved the amplitude of vibrissal whisking to 30° versus 11° in the controls of Group 1. The three treatments also reduced the degree of polyneuronal innervation of target muscle fibers to 37% versus 58% in Group 1. These findings indicate that forced vibrissal use and manual stimulation, either alone or sequentially, reduce target muscle polyinnervation and improve recovery of whisking function when both the sensory and the motor components of the trigemino-facial system regenerate.

Comparison of Facial Nerve Paralysis in Adults and Children

PubMed Central

Cha, Chang Il; Hong, Chang Kee; Park, Moon Suh

2008-01-01

Purpose Facial nerve injury can occur in the regions ranging from the cerebral cortex to the motor end plate in the face, and from many causes including trauma, viral infection, and idiopathic factors. Facial nerve paralysis in children, however, may differ from that in adults. We, therefore, evaluated its etiology and recovery rate in children and adults. Materials and Methods We retrospectively evaluated the records of 975 patients, ranging in age from 0 to 88 years, who displayed facial palsy at Kyung Hee Medical Center between January 1986 and July 2005. Results The most frequent causes of facial palsy in adults were Bell's palsy (54.9%), infection (26.8%), trauma (5.9%), iatrogenic (2.0%), and tumors (1.8%), whereas the most frequent causes of facial palsy in children were Bell's palsy (66.2%), infection (14.6%), trauma (13.4%), birth trauma (3.2%), and leukemia (1.3%). Recovery rates in adults were 91.4% for Bell's palsy, 89.0% for infection, and 64.3% for trauma, whereas recovery rates in children were 93.1% for Bell's palsy, 90.9% for infection, and 42.9% for trauma. Conclusion These results show that causes of facial palsy are similar in adults and children, and recovery rates in adults and children are not significantly different. PMID:18972592

Role of Netrin-1 Signaling in Nerve Regeneration

PubMed Central

Dun, Xin-Peng; Parkinson, David B.

2017-01-01

Netrin-1 was the first axon guidance molecule to be discovered in vertebrates and has a strong chemotropic function for axonal guidance, cell migration, morphogenesis and angiogenesis. It is a secreted axon guidance cue that can trigger attraction by binding to its canonical receptors Deleted in Colorectal Cancer (DCC) and Neogenin or repulsion through binding the DCC/Uncoordinated (Unc5) A–D receptor complex. The crystal structures of Netrin-1/receptor complexes have recently been revealed. These studies have provided a structure based explanation of Netrin-1 bi-functionality. Netrin-1 and its receptor are continuously expressed in the adult nervous system and are differentially regulated after nerve injury. In the adult spinal cord and optic nerve, Netrin-1 has been considered as an inhibitor that contributes to axon regeneration failure after injury. In the peripheral nervous system, Netrin-1 receptors are expressed in Schwann cells, the cell bodies of sensory neurons and the axons of both motor and sensory neurons. Netrin-1 is expressed in Schwann cells and its expression is up-regulated after peripheral nerve transection injury. Recent studies indicated that Netrin-1 plays a positive role in promoting peripheral nerve regeneration, Schwann cell proliferation and migration. Targeting of the Netrin-1 signaling pathway could develop novel therapeutic strategies to promote peripheral nerve regeneration and functional recovery. PMID:28245592

Relation between a first branchial cleft anomaly and the facial nerve.

PubMed

Guo, Yu-Xing; Guo, Chuan-Bin

2012-04-01

Relations between first branchial cleft anomalies and the facial nerve vary. We reviewed 41 patients' medical records and pathological sections to clarify the relation, and found that those on the right side in young patients, which were Work type II and situated low down, were likely to be deep to the facial nerve. Copyright © 2011 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Surgical management of facial nerve paralysis in the pediatric population.

PubMed

Barr, Jason S; Katz, Karin A; Hazen, Alexes

2011-11-01

In the pediatric patient population, both the pathology and the surgical managements of seventh cranial nerve palsy are complicated by the small size of the patients. Adding to the technical difficulty is the relative infrequency of the diagnosis, thus making it harder to become proficient in the management of the condition. The magnitude of the functional and aesthetic deficits these children manifest is significantly troubling to both the patient and the parents, which makes immediate attention, treatment, and functional restoration essential. A literature search using PubMed (http://www.pubmed.org) was undertaken to identify the current state of surgical management of pediatric facial paralysis. Although a multitude of techniques have been used, the ideal reconstructive procedure that addresses all of the functional and cosmetic needs of these children has yet to be described. Certainly, future research and innovative thinking will yield progressively better techniques that may, one day, emulate the native facial musculature with remarkable precision. The necessity for surgical intervention in children with facial nerve paralysis differs depending on many factors including the acute/chronic nature of the defect as well as the extent of functional and cosmetic damage. In this article, we review the surgical procedures that have been used to treat pediatric facial nerve paralysis and provide therapeutic facial reanimation. Copyright © 2011 Elsevier Inc. All rights reserved.

Astrocytes as gate-keepers in optic nerve regeneration--a mini-review.

PubMed

García, Dana M; Koke, Joseph R

2009-02-01

Animals that develop without extra-embryonic membranes (anamniotes--fish, amphibians) have impressive regenerative capacity, even to the extent of replacing entire limbs. In contrast, animals that develop within extra-embryonic membranes (amniotes--reptiles, birds, mammals) have limited capacity for regeneration as adults, particularly in the central nervous system (CNS). Much is known about the process of nerve development in fish and mammals and about regeneration after lesions in the CNS in fish and mammals. Because the retina of the eye and optic nerve are functionally part of the brain and are accessible in fish, frogs, and mice, optic nerve lesion and regeneration (ONR) has been extensively used as a model system for study of CNS nerve regeneration. When the optic nerve of a mouse is severed, the axons leading into the brain degenerate. Initially, the cut end of the axons on the proximal, eye-side of the injury sprout neurites which begin to grow into the lesion. Simultaneously, astrocytes of the optic nerve become activated to initiate wound repair as a first step in reestablishing the structural integrity of the optic nerve. This activation appears to initiate a cascade of molecular signals resulting in apoptotic cell death of the retinal ganglion cells axons of which make up the neural component of the optic nerve; regeneration fails and the injury is permanent. Evidence specifically implicating astrocytes comes from studies showing selective poisoning of astrocytes at the optic nerve lesion, along with activation of a gene whose product blocks apoptosis in retinal ganglion cells, creates conditions favorable to neurites sprouting from the cut proximal stump, growing through the lesion and into the distal portion of the injured nerve, eventually reaching appropriate targets in the brain. In anamniotes, astrocytes ostensibly present no such obstacle since optic nerve regeneration occurs without intervention; however, no systematic study of glial involvement

Neural tissue engineering options for peripheral nerve regeneration.

PubMed

Gu, Xiaosong; Ding, Fei; Williams, David F

2014-08-01

Tissue engineered nerve grafts (TENGs) have emerged as a potential alternative to autologous nerve grafts, the gold standard for peripheral nerve repair. Typically, TENGs are composed of a biomaterial-based template that incorporates biochemical cues. A number of TENGs have been used experimentally to bridge long peripheral nerve gaps in various animal models, where the desired outcome is nerve tissue regeneration and functional recovery. So far, the translation of TENGs to the clinic for use in humans has met with a certain degree of success. In order to optimize the TENG design and further approach the matching of TENGs with autologous nerve grafts, many new cues, beyond the traditional ones, will have to be integrated into TENGs. Furthermore, there is a strong requirement for monitoring the real-time dynamic information related to the construction of TENGs. The aim of this opinion paper is to specifically and critically describe the latest advances in the field of neural tissue engineering for peripheral nerve regeneration. Here we delineate new attempts in the design of template (or scaffold) materials, especially in the context of biocompatibility, the choice and handling of support cells, and growth factor release systems. We further discuss the significance of RNAi for peripheral nerve regeneration, anticipate the potential application of RNAi reagents for TENGs, and speculate on the possible contributions of additional elements, including angiogenesis, electrical stimulation, molecular inflammatory mediators, bioactive peptides, antioxidant reagents, and cultured biological constructs, to TENGs. Finally, we consider that a diverse array of physicochemical and biological cues must be orchestrated within a TENG to create a self-consistent coordinated system with a close proximity to the regenerative microenvironment of the peripheral nervous system. Copyright © 2014 Elsevier Ltd. All rights reserved.

Partial lesions of the intratemporal segment of the facial nerve: graft versus partial reconstruction.

PubMed

Bento, Ricardo F; Salomone, Raquel; Brito, Rubens; Tsuji, Robinson K; Hausen, Mariana

2008-09-01

In cases of partial lesions of the intratemporal segment of the facial nerve, should the surgeon perform an intraoperative partial reconstruction, or partially remove the injured segment and place a graft? We present results from partial lesion reconstruction on the intratemporal segment of the facial nerve. A retrospective study on 42 patients who presented partial lesions on the intratemporal segment of the facial nerve was performed between 1988 and 2005. The patients were divided into 3 groups based on the procedure used: interposition of the partial graft on the injured area of the nerve (group 1; 12 patients); keeping the preserved part and performing tubulization (group 2; 8 patients); and dividing the parts of the injured nerve (proximal and distal) and placing a total graft of the sural nerve (group 3; 22 patients). Fracture of the temporal bone was the most frequent cause of the lesion in all groups, followed by iatrogenic causes (p < 0.005). Those who obtained results lower than or equal to III on the House-Brackmann scale were 1 (8.3%) of the patients in group 1, none (0.0%) of the patients in group 2, and 15 (68.2%) of the patients in group 3 (p <0.001). The best surgical technique for therapy of a partial lesion of the facial nerve is still questionable. Among these 42 patients, the best results were those from the total graft of the facial nerve.

Microvascular Decompression for Treatment of Trigeminal Neuralgia in Patient with Facial Nerve Schwannoma.

PubMed

Marinelli, John P; Van Gompel, Jamie J; Link, Michael J; Carlson, Matthew L

2018-05-01

Secondary trigeminal neuralgia (TN) is uncommon. When a space-occupying lesion with mass effect is identified, the associated TN is often exclusively attributed to the tumor. This report illustrates the importance of considering coexistent actionable pathology when surgically treating secondary TN. A 51-year-old woman presented with abrupt-onset TN of the V2 and V3 nerve divisions with hypesthesia. She denied changes in hearing, balance, or facial nerve dysfunction. Magnetic resonance imaging revealed a 1.6-cm contrast-enhancing cerebellopontine angle tumor that effaced the trigeminal nerve, consistent with a vestibular schwannoma. In addition, a branch of the superior cerebellar artery abutted the cisternal segment of the trigeminal nerve on T2-weighted thin-slice magnetic resonance imaging. Intraoperative electrical stimulation of the tumor elicited a response from the facial nerve at low threshold over the entire accessible tumor surface, indicating that the tumor was a facial nerve schwannoma. Considering the patient's lack of facial nerve deficit and that the tumor exhibited no safe entry point for intracapsular debulking, tumor resection was not performed. Working between the tumor and tentorium, a branch of the superior cerebellar artery was identified and decompressed with a Teflon pad. At last follow-up, the patient exhibited resolution of her TN. Her hearing and facial nerve function remained intact. Despite obstruction from a medium-sized tumor, it is still possible to achieve microvascular decompression of the fifth cranial nerve. This emphasizes the importance of considering other actionable pathology during surgical management of presumed tumor-induced TN. Further, TN is relatively uncommon with medium-sized vestibular schwannomas and coexistent causes should be considered. Copyright © 2018 Elsevier Inc. All rights reserved.

Facial Nerve Repair: Fibrin Adhesive Coaptation versus Epineurial Suture Repair in a Rodent Model

PubMed Central

Knox, Christopher J.; Hohman, Marc H.; Kleiss, Ingrid J.; Weinberg, Julie S.; Heaton, James T.; Hadlock, Tessa A.

2013-01-01

Objectives/Hypothesis Repair of the transected facial nerve has traditionally been accomplished with microsurgical neurorrhaphy; however, fibrin adhesive coaptation (FAC) of peripheral nerves has become increasingly popular over the past decade. We compared functional recovery following suture neurorrhaphy to FAC in a rodent facial nerve model. Study Design Prospective, randomized animal study. Methods Sixteen rats underwent transection and repair of the facial nerve proximal to the pes anserinus. Eight animals underwent epineurial suture (ES) neurorrhaphy, and eight underwent repair with fibrin adhesive (FA). Surgical times were documented for all procedures. Whisking function was analyzed on a weekly basis for both groups across 15 weeks of recovery. Results Rats experienced whisking recovery consistent in time course and degree with prior studies of rodent facial nerve transection and repair. There were no significant differences in whisking amplitude, velocity, or acceleration between suture and FA groups. However, the neurorrhaphy time with FA was 70% shorter than for ES (P < 0.05). Conclusion Although we found no difference in whisking recovery between suture and FA repair of the main trunk of the rat facial nerve, the significantly shorter operative time for FA repair makes this technique an attractive option. The relative advantages of both techniques are discussed. PMID:23188676

Facial nerve repair: fibrin adhesive coaptation versus epineurial suture repair in a rodent model.

PubMed

Knox, Christopher J; Hohman, Marc H; Kleiss, Ingrid J; Weinberg, Julie S; Heaton, James T; Hadlock, Tessa A

2013-07-01

Repair of the transected facial nerve has traditionally been accomplished with microsurgical neurorrhaphy; however, fibrin adhesive coaptation (FAC) of peripheral nerves has become increasingly popular over the past decade. We compared functional recovery following suture neurorrhaphy to FAC in a rodent facial nerve model. Prospective, randomized animal study. Sixteen rats underwent transection and repair of the facial nerve proximal to the pes anserinus. Eight animals underwent epineurial suture (ES) neurorrhaphy, and eight underwent repair with fibrin adhesive (FA). Surgical times were documented for all procedures. Whisking function was analyzed on a weekly basis for both groups across 15 weeks of recovery. Rats experienced whisking recovery consistent in time course and degree with prior studies of rodent facial nerve transection and repair. There were no significant differences in whisking amplitude, velocity, or acceleration between suture and FA groups. However, the neurorrhaphy time with FA was 70% shorter than for ES (P < 0.05). Although we found no difference in whisking recovery between suture and FA repair of the main trunk of the rat facial nerve, the significantly shorter operative time for FA repair makes this technique an attractive option. The relative advantages of both techniques are discussed. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

Penetrating gunshot wound to the head: transotic approach to remove the bullet and masseteric-facial nerve anastomosis for early facial reanimation.

PubMed

Donnarumma, Pasquale; Tarantino, Roberto; Gennaro, Paolo; Mitro, Valeria; Valentini, Valentino; Magliulo, Giuseppe; Delfini, Roberto

2014-01-01

Gunshot wounds to the head (GSWH) account for the majority of penetrating brain injuries, and are the most lethal. Since they are rare in Europe, the number of neurosurgeons who have experienced this type of traumatic injury is decreasing, and fewer cases are reported in the literature. We describe a case of gunshot to the temporal bone in which the bullet penetrated the skull resulting in the facial nerve paralysis. It was excised with the transotic approach. Microsurgical anastomosis among the masseteric nerve and the facial nerve was performed. GSWH are often devastating. The in-hospital mortality for civilians with penetrating craniocerebral injury is very high. Survivors often have high rate of complications. When facial paralysis is present, masseteric-facial direct neurorraphy represent a good treatment.

Bioengineered nerve regeneration and muscle reinnervation

PubMed Central

Kingham, Paul J; Terenghi, Giorgio

2006-01-01

The peripheral nervous system has the intrinsic capacity to regenerate but the reinnervation of muscles is often suboptimal and results in limited recovery of function. Injuries to nerves that innervate complex organs such as the larynx are particularly difficult to treat. The many functions of the larynx have evolved through the intricate neural regulation of highly specialized laryngeal muscles. In this review, we examine the responses of nerves and muscles to injury, focusing on changes in the expression of neurotrophic factors, and highlight differences between the skeletal limb and laryngeal muscle systems. We also describe how artificial nerve conduits have become a useful tool for delivery of neurotrophic factors as therapeutic agents to promote peripheral nerve repair and might eventually be useful in the treatment of laryngeal nerve injury. PMID:17005023

Stress Altered Stem Cells with Decellularized Allograft to Improve Rate of Nerve Regeneration

DTIC Science & Technology

2015-12-01

AWARD  NUMBER:      W81XWH-­13-­1-­0298   TITLE:    “Stress Altered Stem Cells with Decellularized Allograft to Improve Rate of Nerve Regeneration...Cells with Decellularized Allograft to Improve Rate of Nerve Regeneration 5b. GRANT NUMBER W81XWH-13-1-0298 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S... allograft , neural regeneration, stem cells, stress altered cells, peripheral nerve injury model, nerve graft 3 This comprehensive final report summarizes

Regenerated Sciatic Nerve Axons Stimulated through a Chronically Implanted Macro-Sieve Electrode.

PubMed

MacEwan, Matthew R; Zellmer, Erik R; Wheeler, Jesse J; Burton, Harold; Moran, Daniel W

2016-01-01

Sieve electrodes provide a chronic interface for stimulating peripheral nerve axons. Yet, successful utilization requires robust axonal regeneration through the implanted electrode. The present study determined the effect of large transit zones in enhancing axonal regeneration and revealed an intimate neural interface with an implanted sieve electrode. Fabrication of the polyimide sieve electrodes employed sacrificial photolithography. The manufactured macro-sieve electrode (MSE) contained nine large transit zones with areas of ~0.285 mm 2 surrounded by eight Pt-Ir metallized electrode sites. Prior to implantation, saline, or glial derived neurotropic factor (GDNF) was injected into nerve guidance silicone-conduits with or without a MSE. The MSE assembly or a nerve guidance conduit was implanted between transected ends of the sciatic nerve in adult male Lewis rats. At 3 months post-operation, fiber counts were similar through both implant types. Likewise, stimulation of nerves regenerated through a MSE or an open silicone conduit evoked comparable muscle forces. These results showed that nerve regeneration was comparable through MSE transit zones and an open conduit. GDNF had a minimal positive effect on the quality and morphology of fibers regenerating through the MSE; thus, the MSE may reduce reliance on GDNF to augment axonal regeneration. Selective stimulation of several individual muscles was achieved through monopolar stimulation of individual electrodes sites suggesting that the MSE might be an optimal platform for functional neuromuscular stimulation.

Regenerated Sciatic Nerve Axons Stimulated through a Chronically Implanted Macro-Sieve Electrode

PubMed Central

MacEwan, Matthew R.; Zellmer, Erik R.; Wheeler, Jesse J.; Burton, Harold; Moran, Daniel W.

2016-01-01

Sieve electrodes provide a chronic interface for stimulating peripheral nerve axons. Yet, successful utilization requires robust axonal regeneration through the implanted electrode. The present study determined the effect of large transit zones in enhancing axonal regeneration and revealed an intimate neural interface with an implanted sieve electrode. Fabrication of the polyimide sieve electrodes employed sacrificial photolithography. The manufactured macro-sieve electrode (MSE) contained nine large transit zones with areas of ~0.285 mm2 surrounded by eight Pt-Ir metallized electrode sites. Prior to implantation, saline, or glial derived neurotropic factor (GDNF) was injected into nerve guidance silicone-conduits with or without a MSE. The MSE assembly or a nerve guidance conduit was implanted between transected ends of the sciatic nerve in adult male Lewis rats. At 3 months post-operation, fiber counts were similar through both implant types. Likewise, stimulation of nerves regenerated through a MSE or an open silicone conduit evoked comparable muscle forces. These results showed that nerve regeneration was comparable through MSE transit zones and an open conduit. GDNF had a minimal positive effect on the quality and morphology of fibers regenerating through the MSE; thus, the MSE may reduce reliance on GDNF to augment axonal regeneration. Selective stimulation of several individual muscles was achieved through monopolar stimulation of individual electrodes sites suggesting that the MSE might be an optimal platform for functional neuromuscular stimulation. PMID:28008303

Deficiency in monocarboxylate transporter 1 (MCT1) in mice delays regeneration of peripheral nerves following sciatic nerve crush.

PubMed

Morrison, Brett M; Tsingalia, Akivaga; Vidensky, Svetlana; Lee, Youngjin; Jin, Lin; Farah, Mohamed H; Lengacher, Sylvain; Magistretti, Pierre J; Pellerin, Luc; Rothstein, Jeffrey D

2015-01-01

Peripheral nerve regeneration following injury occurs spontaneously, but many of the processes require metabolic energy. The mechanism of energy supply to axons has not previously been determined. In the central nervous system, monocarboxylate transporter 1 (MCT1), expressed in oligodendroglia, is critical for supplying lactate or other energy metabolites to axons. In the current study, MCT1 is shown to localize within the peripheral nervous system to perineurial cells, dorsal root ganglion neurons, and Schwann cells by MCT1 immunofluorescence in wild-type mice and tdTomato fluorescence in MCT1 BAC reporter mice. To investigate whether MCT1 is necessary for peripheral nerve regeneration, sciatic nerves of MCT1 heterozygous null mice are crushed and peripheral nerve regeneration was quantified electrophysiologically and anatomically. Compound muscle action potential (CMAP) recovery is delayed from a median of 21 days in wild-type mice to greater than 38 days in MCT1 heterozygote null mice. In fact, half of the MCT1 heterozygote null mice have no recovery of CMAP at 42 days, while all of the wild-type mice recovered. In addition, muscle fibers remain 40% more atrophic and neuromuscular junctions 40% more denervated at 42 days post-crush in the MCT1 heterozygote null mice than wild-type mice. The delay in nerve regeneration is not only in motor axons, as the number of regenerated axons in the sural sensory nerve of MCT1 heterozygote null mice at 4 weeks and tibial mixed sensory and motor nerve at 3 weeks is also significantly reduced compared to wild-type mice. This delay in regeneration may be partly due to failed Schwann cell function, as there is reduced early phagocytosis of myelin debris and remyelination of axon segments. These data for the first time demonstrate that MCT1 is critical for regeneration of both sensory and motor axons in mice following sciatic nerve crush. Copyright © 2014 Elsevier Inc. All rights reserved.

Infantile inflammatory pseudotumor of the facial nerve as a complication of epidermal nevus syndrome with cholesteatoma.

PubMed

Hato, Naohito; Tsujimura, Mika; Takagi, Taro; Okada, Masahiro; Gyo, Kiyofumi; Tohyama, Mikiko; Tauchi, Hisamichi

2013-12-01

The first reported case of facial paralysis due to an inflammatory pseudotumor (IPT) of the facial nerve as a complication of epidermal nevus syndrome (ENS) is herein presented. A 10-month-old female patient was diagnosed with ENS at 3 months of age. She was referred to us because of moderate left facial paralysis. Epidermal nevi of her left auricle extended deep into the external ear canal. Otoscopy revealed polypous nevi and cholesteatoma debris filling the left ear. Computed tomography showed a soft mass filling the ear canal, including the middle ear, and an enormously enlarged facial nerve. Surgical exploration revealed numerous polypous nevi, external ear cholesteatoma, and tumorous swelling of the facial nerve. The middle ear ossicles were completely lost. The facial paralysis was improved after decompression surgery, but recurred 5 months later. A second operation was conducted 10 months after the first. During this operation, facial nerve decompression was completed from the geniculate ganglion to near the stylomastoid foramen. Histological diagnosis of the facial nerve tumor was IPT probably caused by chronic external ear inflammation induced by epidermal nevi. The facial paralysis gradually improved to House-Blackmann grade III 5 years after the second operation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Corneal nerve regeneration. Correlation between morphology and restoration of sensitivity.

PubMed

de Leeuw, A M; Chan, K Y

1989-09-01

Corneal nerve regeneration was determined in albino rabbits after deepithelialization of the cornea using heptanol. Regeneration was monitored up to 10 weeks by measuring corneal tactile sensitivity using an esthesiometer and by examining stromal and intraepithelial nerve patterns following gold chloride impregnation and acetylcholinesterase staining. Tactile sensitivity was much reduced, possibly absent, up to 2 weeks after wounding. From 2.5-4 weeks, sensitivity recovered rapidly to 60% of prewounding levels and remained unchanged thereafter. In control corneas, a distinct orientation of the basoepithelial leashes towards the nasal-most limbus was observed in the central two-thirds of the cornea. Three days after wounding, neurites that were oriented radially towards the wound center extended into the periphery of the wound area from just beyond the wound margin. At 1 week, regenerating axons were present as single neurites and in the form of modified leashes, mainly at the periphery of the wound area but also more towards the center. At 3 weeks, neurites, regenerated leashes and networks of terminals with terminal endings were found throughout the regenerated epithelium. Regional changes in the orientation of the regenerated leashes were observed also. No further change in the intraepithelial nerve pattern was detectable thereafter up to 10 weeks after wounding. It was concluded that partial restoration of tactile sensitivity following deepithelialization of the cornea is a function of the establishment of a near-normal nerve pattern in the regenerated epithelium and is correlated with the subnormal neural density observed in a previous study.

Facial nerve hemangioma: a rare case involving the vertical segment.

PubMed

Ahmadi, Neda; Newkirk, Kenneth; Kim, H Jeffrey

2013-02-01

This case report and literature review reports on a rare case of facial nerve hemangioma (FNH) involving the vertical facial nerve (FN) segment, and discusses the clinical presentation, imaging, pathogenesis, and management of these rare lesions. A 53-year-old male presented with a 10-year history of right hemifacial twitching and progressive facial paresis (House-Brackmann grading score V/VI). The computed tomography and magnetic resonance imaging studies confirmed an expansile lesion along the vertical FN segment. Excision and histopathologic examination demonstrated FNH. FNHs involving the vertical FN segment are extremely rare. Despite being rare lesions, we believe that familiarity with the presentation and management of FNHs are imperative. Laryngoscope, 2012. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

Neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration.

PubMed

Farkas, Johanna E; Freitas, Polina D; Bryant, Donald M; Whited, Jessica L; Monaghan, James R

2016-08-01

The Mexican axolotl (Ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. The molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. An essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in denervated limbs, and its inhibition must prevent regeneration. Here, we show that the neuronally secreted protein Neuregulin-1 (NRG1) fulfills all these criteria in the axolotl. Immunohistochemistry and in situ hybridization of NRG1 and its active receptor ErbB2 revealed that they are expressed in regenerating blastemas but lost upon denervation. NRG1 was localized to the wound epithelium prior to blastema formation and was later strongly expressed in proliferating blastemal cells. Supplementation by implantation of NRG1-soaked beads rescued regeneration to digits in denervated limbs, and pharmacological inhibition of NRG1 signaling reduced cell proliferation, blocked blastema formation and induced aberrant collagen deposition in fully innervated limbs. Taken together, our results show that nerve-dependent NRG1/ErbB2 signaling promotes blastemal proliferation in the regenerating limb and may play an essential role in blastema formation, thus providing insight into the longstanding question of why nerves are required for axolotl limb regeneration. © 2016. Published by The Company of Biologists Ltd.

Constriction of the buccal branch of the facial nerve produces unilateral craniofacial allodynia.

PubMed

Lewis, Susannah S; Grace, Peter M; Hutchinson, Mark R; Maier, Steven F; Watkins, Linda R

2017-08-01

Despite pain being a sensory experience, studies of spinal cord ventral root damage have demonstrated that motor neuron injury can induce neuropathic pain. Whether injury of cranial motor nerves can also produce nociceptive hypersensitivity has not been addressed. Herein, we demonstrate that chronic constriction injury (CCI) of the buccal branch of the facial nerve results in long-lasting, unilateral allodynia in the rat. An anterograde and retrograde tracer (3000MW tetramethylrhodamine-conjugated dextran) was not transported to the trigeminal ganglion when applied to the injury site, but was transported to the facial nucleus, indicating that this nerve branch is not composed of trigeminal sensory neurons. Finally, intracisterna magna injection of interleukin-1 (IL-1) receptor antagonist reversed allodynia, implicating the pro-inflammatory cytokine IL-1 in the maintenance of neuropathic pain induced by facial nerve CCI. These data extend the prior evidence that selective injury to motor axons can enhance pain to supraspinal circuits by demonstrating that injury of a facial nerve with predominantly motor axons is sufficient for neuropathic pain, and that the resultant pain has a neuroimmune component. Copyright © 2016 Elsevier Inc. All rights reserved.

The intracranial facial nerve as seen through different surgical windows: an extensive anatomosurgical study.

PubMed

Bernardo, Antonio; Evins, Alexander I; Visca, Anna; Stieg, Phillip E

2013-06-01

The facial nerve has a short intracranial course but crosses critical and frequently accessed surgical structures during cranial base surgery. When performing approaches to complex intracranial regions, it is essential to understand the nerve's conventional and topographic anatomy from different surgical perspectives as well as its relationship with surrounding structures. To describe the entire intracranial course of the facial nerve as observed via different neurosurgical approaches and to provide an analytical evaluation of the degree of nerve exposure achieved with each approach. Anterior petrosectomies (middle fossa, extended middle fossa), posterior petrosectomies (translabyrinthine, retrolabyrinthine, transcochlear), a retrosigmoid, a far lateral, and anterior transfacial (extended maxillectomy, mandibular swing) approaches were performed on 10 adult cadaveric heads (20 sides). The degree of facial nerve exposure achieved per segment for each approach was assessed and graded independently by 3 surgeons. The anterior petrosal approaches offered good visualization of the nerve in the cerebellopontine angle and intracanalicular portion superiorly, whereas the posterior petrosectomies provided more direct visualization without the need for cerebellar retraction. The far lateral approach exposed part of the posterior and the entire inferior quadrants, whereas the retrosigmoid approach exposed parts of the superior and inferior quadrants and the entire posterior quadrant. Anterior and anteroinferior exposure of the facial nerve was achieved via the transfacial approaches. The surgical route used must rely on the size, nature, and general location of the lesion, as well as on the capability of the particular approach to better expose the appropriate segment of the facial nerve.

Advances and Future Applications of Augmented Peripheral Nerve Regeneration

PubMed Central

Jones, Salazar; Eisenberg, Howard M.; Jia, Xiaofeng

2016-01-01

Peripheral nerve injuries remain a significant source of long lasting morbidity, disability, and economic costs. Much research continues to be performed in areas related to improving the surgical outcomes of peripheral nerve repair. In this review, the physiology of peripheral nerve regeneration and the multitude of efforts to improve surgical outcomes are discussed. Improvements in tissue engineering that have allowed for the use of synthetic conduits seeded with neurotrophic factors are highlighted. Selected pre-clinical and available clinical data using cell based methods such as Schwann cell, undifferentiated, and differentiated stem cell transplantation to guide and enhance peripheral nerve regeneration are presented. The limitations that still exist in the utility of neurotrophic factors and cell-based therapies are outlined. Strategies that are most promising for translation into the clinical arena are suggested. PMID:27618010

Effects of nerve cells and adhesion molecules on nerve conduit for peripheral nerve regeneration

PubMed Central

Fiorellini, Joseph P.

2017-01-01

Background For peripheral nerve regeneration, recent attentions have been paid to the nerve conduits made by tissue-engineering technique. Three major elements of tissue-engineering are cells, molecules, and scaffolds. Methods In this study, the attachments of nerve cells, including Schwann cells, on the nerve conduit and the effects of both growth factor and adhesion molecule on these attachments were investigated. Results The attachment of rapidly-proliferating cells, C6 cells and HS683 cells, on nerve conduit was better than that of slowly-proliferating cells, PC12 cells and Schwann cells, however, the treatment of nerve growth factor improved the attachment of slowly-proliferating cells. In addition, the attachment of Schwann cells on nerve conduit coated with fibronectin was as good as that of Schwann cells treated with glial cell line-derived neurotrophic factor (GDNF). Conclusions Growth factor changes nerve cell morphology and affects cell cycle time. And nerve growth factor or fibronectin treatment is indispensable for Schwann cell to be used for implantation in artificial nerve conduits. PMID:29090249

Enhancing Peripheral Nerve Regeneration with a Novel Drug Delivering Nerve Conduit

DTIC Science & Technology

2014-10-01

tubes of the PLGA nerve conduit. A polyether sulfone (PES) filter membrane, a polydimethyl siloxane (PDMS) plug and silicone sealant (RTV silicone, Dow...harvested from chicken embryos. 1 DRG/well was plated in 24-well plates coated with laminin (1 µg/ml). Finally, different doses of NGF, GDNF and NGF...application in nerve regeneration, Biomedical Microdevices, in preparation, acknowledgement of federal support (yes) Books or other non-periodical, one

Facial Nerve Paralysis due to Chronic Otitis Media: Prognosis in Restoration of Facial Function after Surgical Intervention

PubMed Central

Kim, Jin; Jung, Gu-Hyun; Park, See-Young

2012-01-01

Purpose Facial paralysis is an uncommon but significant complication of chronic otitis media (COM). Surgical eradication of the disease is the most viable way to overcome facial paralysis therefrom. In an effort to guide treatment of this rare complication, we analyzed the prognosis of facial function after surgical treatment. Materials and Methods A total of 3435 patients with COM, who underwent various otologic surgeries throughout a period of 20 years, were analyzed retrospectively. Forty six patients (1.33%) had facial nerve paralysis caused by COM. We analyzed prognostic factors including delay of surgery, the extent of disease, presence or absence of cholesteatoma and the type of surgery affecting surgical outcomes. Results Surgical intervention had a good effect on the restoration of facial function in cases of shorter duration of onset of facial paralysis to surgery and cases of sudden onset, without cholesteatoma. No previous ear surgery and healthy bony labyrinth indicated a good postoperative prognosis. Conclusion COM causing facial paralysis is most frequently due to cholesteatoma and the presence of cholesteatoma decreased the effectiveness of surgical treatment and indicated a poor prognosis after surgery. In our experience, early surgical intervention can be crucial to recovery of facial function. To prevent recurrent cholesteatoma, which leads to local destruction of the facial nerve, complete eradication of the disease in one procedure cannot be overemphasized for the treatment of patients with COM. PMID:22477011

Serial neurophysiological and neurophysiological examinations for delayed facial nerve palsy in a patient with Fisher syndrome.

PubMed

Umekawa, Motoyuki; Hatano, Keiko; Matsumoto, Hideyuki; Shimizu, Takahiro; Hashida, Hideji

2017-05-27

The patient was a 47-year-old man who presented with diplopia and gait instability with a gradual onset over the course of three days. Neurological examinations showed ophthalmoplegia, diminished tendon reflexes, and truncal ataxia. Tests for anti-GQ1b antibodies and several other antibodies to ganglioside complex were positive. We made a diagnosis of Fisher syndrome. After administration of intravenous immunoglobulin, the patient's symptoms gradually improved. However, bilateral facial palsy appeared during the recovery phase. Brain MRI showed intensive contrast enhancement of bilateral facial nerves. During the onset phase of facial palsy, the amplitude of the compound muscle action potential (CMAP) in the facial nerves was preserved. During the peak phase, the facial CMAP amplitude was within the lower limit of normal values, or mildly decreased. During the recovery phase, the CMAP amplitude was normalized, and the R1 and R2 responses of the blink reflex were prolonged. The delayed facial nerve palsy improved spontaneously, and the enhancement on brain MRI disappeared. Serial neurophysiological and neuroradiological examinations suggested that the main lesions existed in the proximal part of the facial nerves and the mild lesions existed in the facial nerve terminals, probably due to reversible conduction failure.

IGF-1 and Chondroitinase ABC Augment Nerve Regeneration after Vascularized Composite Limb Allotransplantation.

PubMed

Kostereva, Nataliya V; Wang, Yong; Fletcher, Derek R; Unadkat, Jignesh V; Schnider, Jonas T; Komatsu, Chiaki; Yang, Yang; Stolz, Donna B; Davis, Michael R; Plock, Jan A; Gorantla, Vijay S

2016-01-01

Impaired nerve regeneration and inadequate recovery of motor and sensory function following peripheral nerve repair remain the most significant hurdles to optimal functional and quality of life outcomes in vascularized tissue allotransplantation (VCA). Neurotherapeutics such as Insulin-like Growth Factor-1 (IGF-1) and chondroitinase ABC (CH) have shown promise in augmenting or accelerating nerve regeneration in experimental models and may have potential in VCA. The aim of this study was to evaluate the efficacy of low dose IGF-1, CH or their combination (IGF-1+CH) on nerve regeneration following VCA. We used an allogeneic rat hind limb VCA model maintained on low-dose FK506 (tacrolimus) therapy to prevent rejection. Experimental animals received neurotherapeutics administered intra-operatively as multiple intraneural injections. The IGF-1 and IGF-1+CH groups received daily IGF-1 (intramuscular and intraneural injections). Histomorphometry and immunohistochemistry were used to evaluate outcomes at five weeks. Overall, compared to controls, all experimental groups showed improvements in nerve and muscle (gastrocnemius) histomorphometry. The IGF-1 group demonstrated superior distal regeneration as confirmed by Schwann cell (SC) immunohistochemistry as well as some degree of extrafascicular regeneration. IGF-1 and CH effectively promote nerve regeneration after VCA as confirmed by histomorphometric and immunohistochemical outcomes.

Low-Level Laser Irradiation Improves Functional Recovery and Nerve Regeneration in Sciatic Nerve Crush Rat Injury Model

PubMed Central

Wang, Chau-Zen; Chen, Yi-Jen; Wang, Yan-Hsiung; Yeh, Ming-Long; Huang, Mao-Hsiung; Ho, Mei-Ling; Liang, Jen-I; Chen, Chia-Hsin

2014-01-01

The development of noninvasive approaches to facilitate the regeneration of post-traumatic nerve injury is important for clinical rehabilitation. In this study, we investigated the effective dose of noninvasive 808-nm low-level laser therapy (LLLT) on sciatic nerve crush rat injury model. Thirty-six male Sprague Dawley rats were divided into 6 experimental groups: a normal group with or without 808-nm LLLT at 8 J/cm2 and a sciatic nerve crush injury group with or without 808-nm LLLT at 3, 8 or 15 J/cm2. Rats were given consecutive transcutaneous LLLT at the crush site and sacrificed 20 days after the crush injury. Functional assessments of nerve regeneration were analyzed using the sciatic functional index (SFI) and hindlimb range of motion (ROM). Nerve regeneration was investigated by measuring the myelin sheath thickness of the sciatic nerve using transmission electron microscopy (TEM) and by analyzing the expression of growth-associated protein 43 (GAP43) in sciatic nerve using western blot and immunofluorescence staining. We found that sciatic-injured rats that were irradiated with LLLT at both 3 and 8 J/cm2 had significantly improved SFI but that a significant improvement of ROM was only found in rats with LLLT at 8 J/cm2. Furthermore, the myelin sheath thickness and GAP43 expression levels were significantly enhanced in sciatic nerve-crushed rats receiving 808-nm LLLT at 3 and 8 J/cm2. Taken together, these results suggest that 808-nm LLLT at a low energy density (3 J/cm2 and 8 J/cm2) is capable of enhancing sciatic nerve regeneration following a crush injury. PMID:25119457

Neural stem cells promote nerve regeneration through IL12-induced Schwann cell differentiation.

PubMed

Lee, Don-Ching; Chen, Jong-Hang; Hsu, Tai-Yu; Chang, Li-Hsun; Chang, Hsu; Chi, Ya-Hui; Chiu, Ing-Ming

2017-03-01

Regeneration of injured peripheral nerves is a slow, complicated process that could be improved by implantation of neural stem cells (NSCs) or nerve conduit. Implantation of NSCs along with conduits promotes the regeneration of damaged nerve, likely because (i) conduit supports and guides axonal growth from one nerve stump to the other, while preventing fibrous tissue ingrowth and retaining neurotrophic factors; and (ii) implanted NSCs differentiate into Schwann cells and maintain a growth factor enriched microenvironment, which promotes nerve regeneration. In this study, we identified IL12p80 (homodimer of IL12p40) in the cell extracts of implanted nerve conduit combined with NSCs by using protein antibody array and Western blotting. Levels of IL12p80 in these conduits are 1.6-fold higher than those in conduits without NSCs. In the sciatic nerve injury mouse model, implantation of NSCs combined with nerve conduit and IL12p80 improves motor recovery and increases the diameter up to 4.5-fold, at the medial site of the regenerated nerve. In vitro study further revealed that IL12p80 stimulates the Schwann cell differentiation of mouse NSCs through the phosphorylation of signal transducer and activator of transcription 3 (Stat3). These results suggest that IL12p80 can trigger Schwann cell differentiation of mouse NSCs through Stat3 phosphorylation and enhance the functional recovery and the diameter of regenerated nerves in a mouse sciatic nerve injury model. Copyright © 2016 Elsevier Inc. All rights reserved.

Resveratrol Promotes Nerve Regeneration via Activation of p300 Acetyltransferase-Mediated VEGF Signaling in a Rat Model of Sciatic Nerve Crush Injury.

PubMed

Ding, Zhuofeng; Cao, Jiawei; Shen, Yu; Zou, Yu; Yang, Xin; Zhou, Wen; Guo, Qulian; Huang, Changsheng

2018-01-01

Peripheral nerve injuries are generally associated with incomplete restoration of motor function. The slow rate of nerve regeneration after injury may account for this. Although many benefits of resveratrol have been shown in the nervous system, it is not clear whether resveratrol could promote fast nerve regeneration and motor repair after peripheral nerve injury. This study showed that the motor deficits caused by sciatic nerve crush injury were alleviated by daily systematic resveratrol treatment within 10 days. Resveratrol increased the number of axons in the distal part of the injured nerve, indicating enhanced nerve regeneration. In the affected ventral spinal cord, resveratrol enhanced the expression of several vascular endothelial growth factor family proteins (VEGFs) and increased the phosphorylation of p300 through Akt signaling, indicating activation of p300 acetyltransferase. Inactivation of p300 acetyltransferase reversed the resveratrol-induced expression of VEGFs and motor repair in rats that had undergone sciatic nerve crush injury. The above results indicated that daily systematic resveratrol treatment promoted nerve regeneration and led to rapid motor repair. Resveratrol activated p300 acetyltransferase-mediated VEGF signaling in the affected ventral spinal cord, which may have thus contributed to the acceleration of nerve regeneration and motor repair.

Myelinated sensory and alpha motor axon regeneration in peripheral nerve neuromas

NASA Technical Reports Server (NTRS)

Macias, M. Y.; Lehman, C. T.; Sanger, J. R.; Riley, D. A.

1998-01-01

Histochemical staining for carbonic anhydrase and cholinesterase (CE) activities was used to analyze sensory and motor axon regeneration, respectively, during neuroma formation in transected and tube-encapsulated peripheral nerves. Median-ulnar and sciatic nerves in the rodent model permitted testing whether a 4 cm greater distance of the motor neuron soma from axotomy site or intrinsic differences between motor and sensory neurons influenced regeneration and neuroma formation 10, 30, and 90 days later. Ventral root radiculotomy confirmed that CE-stained axons were 97% alpha motor axons. Distance significantly delayed axon regeneration. When distance was negligible, sensory axons grew out sooner than motor axons, but motor axons regenerated to a greater quantity. These results indicate regeneration differences between axon subtypes and suggest more extensive branching of motor axons within the neuroma. Thus, both distance from injury site to soma and inherent motor and sensory differences should be considered in peripheral nerve repair strategies.

[Treatment of idiopathic peripheral facial nerve paralysis (Bell's palsy)].

PubMed

Meyer, Martin Willy; Hahn, Christoffer Holst

2013-01-28

Bell's palsy is defined as an idiopathic peripheral facial nerve paralysis of sudden onset. It affects 11-40 persons per 100,000 per annum. Many patients recover without intervention; however, up to 30% have poor recovery of facial muscle control and experience facial disfigurement. The aim of this study was to make an overview of which pharmacological treatments have been used to improve outcomes. The available evidence from randomized controlled trials shows significant benefit from treating Bell's palsy with corticosteroids but shows no benefit from antivirals.

Peripheral Nerve Regeneration by Secretomes of Stem Cells from Human Exfoliated Deciduous Teeth.

PubMed

Sugimura-Wakayama, Yukiko; Katagiri, Wataru; Osugi, Masashi; Kawai, Takamasa; Ogata, Kenichi; Sakaguchi, Kohei; Hibi, Hideharu

2015-11-15

Peripheral nerve regeneration across nerve gaps is often suboptimal, with poor functional recovery. Stem cell transplantation-based regenerative therapy is a promising approach for axon regeneration and functional recovery of peripheral nerve injury; however, the mechanisms remain controversial and unclear. Recent studies suggest that transplanted stem cells promote tissue regeneration through a paracrine mechanism. We investigated the effects of conditioned media derived from stem cells from human exfoliated deciduous teeth (SHED-CM) on peripheral nerve regeneration. In vitro, SHED-CM-treated Schwann cells exhibited significantly increased proliferation, migration, and the expression of neuron-, extracellular matrix (ECM)-, and angiogenesis-related genes. SHED-CM stimulated neuritogenesis of dorsal root ganglia and increased cell viability. Similarly, SHED-CM enhanced tube formation in an angiogenesis assay. In vivo, a 10-mm rat sciatic nerve gap model was bridged by silicon conduits containing SHED-CM or serum-free Dulbecco's modified Eagle's medium. Light and electron microscopy confirmed that the number of myelinated axons and axon-to-fiber ratio (G-ratio) were significantly higher in the SHED-CM group at 12 weeks after nerve transection surgery. The sciatic functional index (SFI) and gastrocnemius (target muscle) wet weight ratio demonstrated functional recovery. Increased compound muscle action potentials and increased SFI in the SHED-CM group suggested sciatic nerve reinnervation of the target muscle and improved functional recovery. We also observed reduced muscle atrophy in the SHED-CM group. Thus, SHEDs may secrete various trophic factors that enhance peripheral nerve regeneration through multiple mechanisms. SHED-CM may therefore provide a novel therapy that creates a more desirable extracellular microenvironment for peripheral nerve regeneration.

Mechanical Loading for Peripheral Nerve Stabilization and Regeneration

DTIC Science & Technology

2012-10-01

Dahlin, L., Johansson, F., Lindwall, C., and Kanje, M. Chapter 28: Future perspective in peripheral nerve reconstruction . Int Rev Neurobiol 87, 507...Genden, E.M., MacKinnon, S.E., Doolabh, V.B., and Hunter, D.A. Regeneration through long nerve grafts in the swine model. Microsurgery 18, 379, 1998. 12

[Bilateral facial nerve palsy associated with Epstein-Barr virus infection in a 3-year-old boy].

PubMed

Grassin, M; Rolland, A; Leboucq, N; Roubertie, A; Rivier, F; Meyer, P

2017-06-01

Bilateral facial nerve palsy is a rare and sometimes difficult diagnosis. We describe a case of bilateral simultaneous facial nerve palsy associated with Epstein-Barr virus (EBV) infection in a 3-year-old boy. Several symptoms led to the diagnosis of EBV infection: the clinical situation (fever, stomachache, and throat infection), white blood cell count (5300/mm 3 with 70% lymphocyte count), seroconversion with EBV-specific antibodies, lymphocytic meningitis, and a positive blood EBV polymerase chain reaction (9.3×10 3 copies of EBV-DNA). An MRI brain scan showed bilateral gadolinium enhancement of the facial nerve. A treatment plan with IV antibiotics (ceftriaxone) and corticosteroids was implemented. Antibiotics were stopped after the diagnosis of Lyme disease was ruled out. The patient's facial weakness improved within a few weeks. Bilateral facial nerve palsy is rare and, unlike unilateral facial palsy, it is idiopathic in only 20% of cases. Therefore, it requires further investigation and examination to search for the underlying etiology. Lyme disease is the first infectious disease that should be considered in children, especially in endemic areas. An antibiotic treatment effective against Borrelia burgdorferi should be set up until the diagnosis is negated or confirmed. Further examination should include a blood test (such as immunologic testing, and serologic testing for viruses and bacterium with neurological tropism), a cerebrospinal fluid test, and an MRI brain scan to exclude any serious or curable underlying etiology. Facial bilateral nerve palsy associated with EBV is rarely described in children. Neurological complications have been reported in 7% of all EBV infections. The facial nerve is the most frequently affected of all cranial nerves. Facial palsy described in EBV infections is bilateral in 35% of all cases. The physiopathology is currently unknown. Prognosis is good most of the time. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Motor fiber organization in the extratemporal trunk of the facial nerve in rats: A retrograde Fluoro-Gold study

PubMed Central

CHEN, LIJIE; HU, MIN; ZHANG, LIHAI; LIU, SANXIA; LUO, JINCHAO; DENG, TIANZHENG; TAO, YE

2012-01-01

Understanding the microanatomy of the facial nerve is vital to functional restoration of facial nerve injury. This study aimed to locate the spatial orientation of five branches in the extratemporal trunk of the rat facial nerve (ETFN). Fifteen adult Sprague-Dawley albino rats were divided randomly into five groups corresponding to the five facial nerves. Fluoro-Gold™ (FG) was applied to one branch in all three rats in each group. The trunk of the facial nerve was cut at three points for fluorescence detection. Staining results showed that each branch of the facial motor nerve had a topographical orientation in the distal part of the ETFN. The temporal branch was located in the medial and acroscopic quadrant of the nerve trunk. The zygomatic branch was located in the lateral and acroscopic quadrant. The buccal branch occupied the upper half of the nerve trunk, whereas the mandibular branch occupied the lower half. The cervical branch presented a square-shaped distribution in the lateral nerve trunk. In the middle part of the ETFN, the topographical orientation remained clear, but the FG-labeled zone was extended to some extent. In the stylomastoid foramen region, all branches diffused, thereby blurring the orientation. In conclusion, each branch of the facial motor nerve had a topographical orientation and distribution in the crotch and middle part of the ETFN, but the branches diffused near the stylomastoid foramen. PMID:23226737

Remodeling of motor units after nerve regeneration studied by quantitative electromyography.

PubMed

Krarup, Christian; Boeckstyns, Michel; Ibsen, Allan; Moldovan, Mihai; Archibald, Simon

2016-02-01

Peripheral nerve has the capacity to regenerate after nerve lesions; during reinnervation of muscle motor units are gradually reestablished. The aim of this study was to follow the time course of reestablishing and remodeling of motor units in relation to recovery of force after different types of nerve repair. Reinnervation of muscle was compared clinically and electrophysiologically in complete median or ulnar nerve lesions with short gap lengths in the distal forearm repaired with a collagen nerve conduit (11 nerves) or nerve suture (10 nerves). Reestablishment of motor units was studied by quantitative EMG and recording of evoked compound muscle action potential (CMAP) during a 24-month observation period after nerve repair. Force recovered partially to about 80% of normal. Denervation activity gradually decreased during reinnervation though it was still increased at 24 months. Nascent motor unit potentials (MUPs) at early reinnervation were prolonged and polyphasic. During longitudinal studies, MUPs remained prolonged and their amplitudes gradually increased markedly. Firing of MUPs was unstable throughout the study. CMAPs gradually increased and the number of motor units recovered to approximately 20% of normal. There was weak evidence of CMAP amplitude recovery after suture ahead of conduit repair but without treatment related differences at 2 years. Surgical repair of nerve lesions with a nerve conduit or suture supported recovery of force and of motor unit reinnervation to the same extent. Changes occurred at a higher rate during early regeneration and slower after 12 months but should be followed for at least 2 years to assess outcome. EMG changes reflected extensive remodeling of motor units from early nascent units to a mature state with greatly enlarged units due to axonal regeneration and collateral sprouting and maturation of regenerated nerve and reinnervated muscle fibers after both types of repair. Remodeling of motor units after peripheral nerve

Facial blanching after inferior alveolar nerve block anesthesia: an unusual complication.

PubMed

Kang, Sang-Hoon; Won, Yu-Jin

2017-12-01

The present case report describes a complication involving facial blanching symptoms occurring during inferior alveolar nerve block anesthesia (IANBA). Facial blanching after IANBA can be caused by the injection of an anesthetic into the maxillary artery area, affecting the infraorbital artery.

Optical stimulation of the facial nerve: a surgical tool?

NASA Astrophysics Data System (ADS)

Richter, Claus-Peter; Teudt, Ingo Ulrik; Nevel, Adam E.; Izzo, Agnella D.; Walsh, Joseph T., Jr.

2008-02-01

One sequela of skull base surgery is the iatrogenic damage to cranial nerves. Devices that stimulate nerves with electric current can assist in the nerve identification. Contemporary devices have two main limitations: (1) the physical contact of the stimulating electrode and (2) the spread of the current through the tissue. In contrast to electrical stimulation, pulsed infrared optical radiation can be used to safely and selectively stimulate neural tissue. Stimulation and screening of the nerve is possible without making physical contact. The gerbil facial nerve was irradiated with 250-μs-long pulses of 2.12 μm radiation delivered via a 600-μm-diameter optical fiber at a repetition rate of 2 Hz. Muscle action potentials were recorded with intradermal electrodes. Nerve samples were examined for possible tissue damage. Eight facial nerves were stimulated with radiant exposures between 0.71-1.77 J/cm2, resulting in compound muscle action potentials (CmAPs) that were simultaneously measured at the m. orbicularis oculi, m. levator nasolabialis, and m. orbicularis oris. Resulting CmAP amplitudes were 0.3-0.4 mV, 0.15-1.4 mV and 0.3-2.3 mV, respectively, depending on the radial location of the optical fiber and the radiant exposure. Individual nerve branches were also stimulated, resulting in CmAP amplitudes between 0.2 and 1.6 mV. Histology revealed tissue damage at radiant exposures of 2.2 J/cm2, but no apparent damage at radiant exposures of 2.0 J/cm2.

Spider Silk Constructs Enhance Axonal Regeneration and Remyelination in Long Nerve Defects in Sheep

PubMed Central

Radtke, Christine; Allmeling, Christina; Waldmann, Karl-Heinz; Reimers, Kerstin; Thies, Kerstin; Schenk, Henning C.; Hillmer, Anja; Guggenheim, Merlin; Brandes, Gudrun; Vogt, Peter M.

2011-01-01

Background Surgical reapposition of peripheral nerve results in some axonal regeneration and functional recovery, but the clinical outcome in long distance nerve defects is disappointing and research continues to utilize further interventional approaches to optimize functional recovery. We describe the use of nerve constructs consisting of decellularized vein grafts filled with spider silk fibers as a guiding material to bridge a 6.0 cm tibial nerve defect in adult sheep. Methodology/Principal Findings The nerve constructs were compared to autologous nerve grafts. Regeneration was evaluated for clinical, electrophysiological and histological outcome. Electrophysiological recordings were obtained at 6 months and 10 months post surgery in each group. Ten months later, the nerves were removed and prepared for immunostaining, electrophysiological and electron microscopy. Immunostaining for sodium channel (NaV 1.6) was used to define nodes of Ranvier on regenerated axons in combination with anti-S100 and neurofilament. Anti-S100 was used to identify Schwann cells. Axons regenerated through the constructs and were myelinated indicating migration of Schwann cells into the constructs. Nodes of Ranvier between myelin segments were observed and identified by intense sodium channel (NaV 1.6) staining on the regenerated axons. There was no significant difference in electrophysiological results between control autologous experimental and construct implantation indicating that our construct are an effective alternative to autologous nerve transplantation. Conclusions/Significance This study demonstrates that spider silk enhances Schwann cell migration, axonal regrowth and remyelination including electrophysiological recovery in a long-distance peripheral nerve gap model resulting in functional recovery. This improvement in nerve regeneration could have significant clinical implications for reconstructive nerve surgery. PMID:21364921

Cellulose/soy protein composite-based nerve guidance conduits with designed microstructure for peripheral nerve regeneration

NASA Astrophysics Data System (ADS)

Gan, Li; Zhao, Lei; Zhao, Yanteng; Li, Ke; Tong, Zan; Yi, Li; Wang, Xiong; Li, Yinping; Tian, Weiqun; He, Xiaohua; Zhao, Min; Li, Yan; Chen, Yun

2016-10-01

Objective. The objective of this work was to develop nerve guidance conduits from natural polymers, cellulose and soy protein isolate (SPI), by evaluating the effects of cellulose/SPI film-based conduit (CSFC) and cellulose/SPI sponge-based conduit (CSSC) on regeneration of nerve defects in rats. Approach. CSFC and CSSC with the same chemical components were fabricated from cellulose and SPI. Effects of CSSC and CSFC on regeneration of the defective nerve were comparatively investigated in rats with a 10 mm long gap in sciatic nerve. The outcomes of peripheral nerve repair were evaluated by a combination of electrophysiological assessment, Fluoro-Gold retrograde tracing, double NF200/S100 immunofluorescence analysis, toluidine blue staining, and electron microscopy. The probable molecular mechanism was investigated using quantitative real-time PCR (qPCR) analysis. Main results. Compared with CSFC, CSSC had 2.69 times higher porosity and 5.07 times higher water absorption, thus ensuring much higher permeability. The nerve defects were successfully bridged and repaired by CSSC and CSFC. Three months after surgery, the CSSC group had a higher compound muscle action potential amplitude ratio, a higher percentage of positive NF200 and S100 staining, and a higher axon diameter and myelin sheath thickness than the CSFC group, showing the repair efficiency of CSSC was higher than that of CSFC. qPCR analysis indicated the mRNA levels of nerve growth factor, IL-10, IL-6, and growth-associated protein 43 (GAP-43) were higher in the CSSC group. This also indicated that there was better nerve repair with CSSC due to the higher porosity and permeability of CSSC providing a more favourable microenvironment for nerve regeneration than CSFC. Significance. A promising nerve guidance conduit was developed from cellulose/SPI sponge that showed potential for application in the repair of nerve defect. This work also suggests that nerve guidance conduits with better repair efficiency

Effect of Platelet-Rich Fibrin on Peripheral Nerve Regeneration.

PubMed

Şenses, Fatma; Önder, Mustafa E; Koçyiğit, Ismail D; Kul, Oğuz; Aydin, Gülümser; Inal, Elem; Atil, Fethi; Tekin, Umut

2016-10-01

This study aimed to evaluate the effect of platelet-rich fibrin (PRF) on peripheral nerve regeneration on the sciatic nerve of rats by using functional, histopathologic, and electrophysiologic analyses. Thirty female Wistar rats were divided randomly into 3 experimental groups. In group 1 (G1), which was the control group, the sciatic nerve was transected and sutured (n = 10). In group 2 (G2), the sciatic nerve was transected, sutured, and then covered with PRF as a membrane (n = 10). In group 3 (G3), the sciatic nerve was transected, sutured by leaving a 5-mm gap, and then covered by PRF as a nerve guide (n = 10). Functional, histopathologic, and electrophysiologic analyses were performed. The total histopathologic semiquantitative score was significantly higher in G1 compared to G2 and G3 (P < 0.05). Myelin thickness and capillaries were significantly lower in G3 compared to G1 (P < 0.05). There was no statistically significant difference between the groups with regard to the functional and electrophysiologic results. The study results suggest that PRF decreases functional recovery in sciatic nerve injury. Further studies are required to determine the efficacy of PRF on peripheral nerve regeneration.

Facial blanching after inferior alveolar nerve block anesthesia: an unusual complication

PubMed Central

2017-01-01

The present case report describes a complication involving facial blanching symptoms occurring during inferior alveolar nerve block anesthesia (IANBA). Facial blanching after IANBA can be caused by the injection of an anesthetic into the maxillary artery area, affecting the infraorbital artery. PMID:29349355

Gamma Knife radiosurgery for facial nerve schwannomas: a multicenter study.

PubMed

Sheehan, Jason P; Kano, Hideyuki; Xu, Zhiyuan; Chiang, Veronica; Mathieu, David; Chao, Samuel; Akpinar, Berkcan; Lee, John Y K; Yu, James B; Hess, Judith; Wu, Hsiu-Mei; Chung, Wen-Yuh; Pierce, John; Missios, Symeon; Kondziolka, Douglas; Alonso-Basanta, Michelle; Barnett, Gene H; Lunsford, L Dade

2015-08-01

Facial nerve schwannomas (FNSs) are rare intracranial tumors, and the optimal management of these tumors remains unclear. Resection can be undertaken, but the tumor's intimate association with the facial nerve makes resection with neurological preservation quite challenging. Stereotactic radiosurgery (SRS) has been used to treat FNSs, and this study evaluates the outcome of this approach. At 8 medical centers participating in the North American Gamma Knife Consortium (NAGKC), 42 patients undergoing SRS for an FNS were identified, and clinical and radiographic data were obtained for these cases. Males outnumbered females at a ratio of 1.2:1, and the patients' median age was 48 years (range 11-76 years). Prior resection was performed in 36% of cases. The mean tumor volume was 1.8 cm(3), and a mean margin dose of 12.5 Gy (range 11-15 Gy) was delivered to the tumor. At a median follow-up of 28 months, tumor control was achieved in 36 (90%) of the 40 patients with reliable radiographic follow-up. Actuarial tumor control was 97%, 97%, 97%, and 90% at 1, 2, 3, and 5 years postradiosurgery. Preoperative facial nerve function was preserved in 38 of 42 patients, with 60% of evaluable patients having House-Brackmann scores of 1 or 2 at last follow-up. Treated patients with a House-Brackmann score of 1 to 3 were more likely to demonstrate this level of facial nerve function at last evaluation (OR 6.09, 95% CI 1.7-22.0, p = 0.006). Avoidance of temporary or permanent neurological symptoms was more likely to be achieved in patients who received a tumor margin dose of 12.5 Gy or less (log-rank test, p = 0.024) delivered to a tumor of ≤ 1 cm(3) in volume (log-rank test, p = 0.01). Stereotactic radiosurgery resulted in tumor control and neurological preservation in most FNS patients. When the tumor is smaller and the patient exhibits favorable normal facial nerve function, SRS portends a better result. The authors believe that early, upfront SRS may be the treatment of choice for

Fibrin matrices with affinity-based delivery systems and neurotrophic factors promote functional nerve regeneration.

PubMed

Wood, Matthew D; MacEwan, Matthew R; French, Alexander R; Moore, Amy M; Hunter, Daniel A; Mackinnon, Susan E; Moran, Daniel W; Borschel, Gregory H; Sakiyama-Elbert, Shelly E

2010-08-15

Glial-derived neurotrophic factor (GDNF) and nerve growth factor (NGF) have both been shown to enhance peripheral nerve regeneration following injury and target different neuronal populations. The delivery of either growth factor at the site of injury may, therefore, result in quantitative differences in motor nerve regeneration and functional recovery. In this study we evaluated the effect of affinity-based delivery of GDNF or NGF from fibrin-filled nerve guidance conduits (NGCs) on motor nerve regeneration and functional recovery in a 13 mm rat sciatic nerve defect. Seven experimental groups were evaluated consisting of GDNF or NGF and the affinity-based delivery system (DS) within NGCs, control groups excluding the DS and/or growth factor, and nerve isografts. Groups with growth factor in the conduit demonstrated equivalent or superior performance in behavioral tests and relative muscle mass measurements compared to isografts at 12 weeks. Additionally, groups with GDNF demonstrated greater specific twitch and tetanic force production in extensor digitorum longus (EDL) muscle than the isograft control, while groups with NGF produced demonstrated similar force production compared to the isograft control. Assessment of motor axon regeneration by retrograde labeling further revealed that the number of ventral horn neurons regenerating across NGCs containing GDNF and NGF DS was similar to the isograft group and these counts were greater than the groups without growth factor. Overall, the GDNF DS group demonstrated superior functional recovery and equivalent motor nerve regeneration compared to the isograft control, suggesting it has potential as a treatment for motor nerve injury.

How do I manage an acute injury to the facial nerve?

PubMed

Colbert, Serryth; Coombes, Daryl; Godden, Daryl; Cascarini, Luke; Kerawala, Cyrus; Brennan, Peter A

2014-01-01

Paralysis of the facial nerve is a cause of considerable functional and aesthetic disfigurement. Damage to the upper trunk can result in eye complications with the risk of exposure keratitis. Numerous factors influence the therapeutic strategy: the cause of the injury, the time elapsed since injury, functional impairment, and the likelihood of recovery. We discuss the management of an acute injury to the facial nerve and focus on the surgical options. Copyright © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Stereotactic radiotherapy for malignancies involving the trigeminal and facial nerves.

PubMed

Cuneo, K C; Zagar, T M; Brizel, D M; Yoo, D S; Hoang, J K; Chang, Z; Wang, Z; Yin, F F; Das, S K; Green, S; Ready, N; Bhatti, M T; Kaylie, D M; Becker, A; Sampson, J H; Kirkpatrick, J P

2012-06-01

Involvement of a cranial nerve caries a poor prognosis for many malignancies. Recurrent or residual disease in the trigeminal or facial nerve after primary therapy poses a challenge due to the location of the nerve in the skull base, the proximity to the brain, brainstem, cavernous sinus, and optic apparatus and the resulting complex geometry. Surgical resection caries a high risk of morbidity and is often not an option for these patients. Stereotactic radiosurgery and radiotherapy are potential treatment options for patients with cancer involving the trigeminal or facial nerve. These techniques can deliver high doses of radiation to complex volumes while sparing adjacent critical structures. In the current study, seven cases of cancer involving the trigeminal or facial nerve are presented. These patients had unresectable recurrent or residual disease after definitive local therapy. Each patient was treated with stereotactic radiation therapy using a linear accelerator based system. A multidisciplinary approach including neuroradiology and surgical oncology was used to delineate target volumes. Treatment was well tolerated with no acute grade 3 or higher toxicity. One patient who was reirradiated experienced cerebral radionecrosis with mild symptoms. Four of the seven patients treated had no evidence of disease after a median follow up of 12 months (range 2-24 months). A dosimetric analysis was performed to compare intensity modulated fractionated stereotactic radiation therapy (IM-FSRT) to a 3D conformal technique. The dose to 90% (D90) of the brainstem was lower with the IM-FSRT plan by a mean of 13.5 Gy. The D95 to the ipsilateral optic nerve was also reduced with IM-FSRT by 12.2 Gy and the D95 for the optic chiasm was lower with FSRT by 16.3 Gy. Treatment of malignancies involving a cranial nerve requires a multidisciplinary approach. Use of an IM-FSRT technique with a micro-multileaf collimator resulted in a lower dose to the brainstem, optic nerves and chiasm

Facial nerve activity disrupts psychomotor rhythms in the forehead microvasculature.

PubMed

Drummond, Peter D; O'Brien, Geraldine

2011-10-28

Forehead blood flow was monitored in seven participants with a unilateral facial nerve lesion during relaxation, respiratory biofeedback and a sad documentary. Vascular waves at 0.1Hz strengthened during respiratory biofeedback, in tune with breathing cycles that also averaged 0.1Hz. In addition, a psychomotor rhythm at 0.15Hz was more prominent in vascular waveforms on the denervated than intact side of the forehead, both before and during relaxation and the sad documentary. These findings suggest that parasympathetic activity in the facial nerve interferes with the psychomotor rhythm in the forehead microvasculature. Copyright © 2011 Elsevier B.V. All rights reserved.

Concise Review: Tissue-Engineered Skin and Nerve Regeneration in Burn Treatment

PubMed Central

Blais, Mathieu; Parenteau-Bareil, Rémi; Cadau, Sébastien

2013-01-01

Burns not only destroy the barrier function of the skin but also alter the perceptions of pain, temperature, and touch. Different strategies have been developed over the years to cover deep and extensive burns with the ultimate goal of regenerating the barrier function of the epidermis while recovering an acceptable aesthetic aspect. However, patients often complain about a loss of skin sensation and even cutaneous chronic pain. Cutaneous nerve regeneration can occur from the nerve endings of the wound bed, but it is often compromised by scar formation or anarchic wound healing. Restoration of pain, temperature, and touch perceptions should now be a major challenge to solve in order to improve patients' quality of life. In addition, the cutaneous nerve network has been recently highlighted to play an important role in epidermal homeostasis and may be essential at least in the early phase of wound healing through the induction of neurogenic inflammation. Although the nerve regeneration process was studied largely in the context of nerve transections, very few studies have been aimed at developing strategies to improve it in the context of cutaneous wound healing. In this concise review, we provide a description of the characteristics of and current treatments for extensive burns, including tissue-engineered skin approaches to improve cutaneous nerve regeneration, and describe prospective uses for autologous skin-derived adult stem cells to enhance recovery of the skin's sense of touch. PMID:23734060

The relationship between the fistula tract and the facial nerve in type II first branchial cleft anomalies.

PubMed

Ertas, Burak; Gunaydin, Rıza Onder; Unal, Omer Faruk

2015-04-01

To share our experience involving seven patients with type II first branchial cleft anomalies (hereafter, type II anomalies), to determine whether the location of the external fistula openings of the anomalies are associated with the location of the facial nerve tract, and elucidate the relationship between the location of the fistula opening and the facial nerve. The medical records of seven patients who underwent surgery from 2005 to 2013 for type II anomalies were retrospectively examined. The relationship between the fistula opening and the facial nerve was evaluated in each patient with respect to whether the fistula opening was superior or inferior to the mandibular angle. All patients underwent partial parotidectomy, facial nerve exposure, and total excision of the mass together with connection of a small cuff of the external auditory canal skin to the fistula tract. The fistula tracts were located medially to the facial nerve in two patients, and both fistulae had openings inferior to the mandibular angle. The fistula tracts were located laterally to the facial nerve in the remaining five patients: one patient had no external opening, one had an opening inferior to the mandibular angle, and the remaining three had openings superior to the mandibular angle. Because type II anomalies are rare, their diagnosis is difficult. Surgery of such lesions is challenging and associated with a high risk due to their proximity to the facial nerve. We believe that the location of the fistula opening may help to identify the relationship between the anomalous lesion and facial nerve. Studies involving larger series of cases are needed to confirm our hypothesis; however, because of the rarity of this specific anomaly, it will not be easy to compile a large number of cases. We believe that our study will encourage further investigation on this subject. Copyright © 2014. Published by Elsevier Ireland Ltd.

Effects of noninvasive facial nerve stimulation in the dog middle cerebral artery occlusion model of ischemic stroke.

PubMed

Borsody, Mark K; Yamada, Chisa; Bielawski, Dawn; Heaton, Tamara; Castro Prado, Fernando; Garcia, Andrea; Azpiroz, Joaquín; Sacristan, Emilio

2014-04-01

Facial nerve stimulation has been proposed as a new treatment of ischemic stroke because autonomic components of the nerve dilate cerebral arteries and increase cerebral blood flow when activated. A noninvasive facial nerve stimulator device based on pulsed magnetic stimulation was tested in a dog middle cerebral artery occlusion model. We used an ischemic stroke dog model involving injection of autologous blood clot into the internal carotid artery that reliably embolizes to the middle cerebral artery. Thirty minutes after middle cerebral artery occlusion, the geniculate ganglion region of the facial nerve was stimulated for 5 minutes. Brain perfusion was measured using gadolinium-enhanced contrast MRI, and ATP and total phosphate levels were measured using 31P spectroscopy. Separately, a dog model of brain hemorrhage involving puncture of the intracranial internal carotid artery served as an initial examination of facial nerve stimulation safety. Facial nerve stimulation caused a significant improvement in perfusion in the hemisphere affected by ischemic stroke and a reduction in ischemic core volume in comparison to sham stimulation control. The ATP/total phosphate ratio showed a large decrease poststroke in the control group versus a normal level in the stimulation group. The same stimulation administered to dogs with brain hemorrhage did not cause hematoma enlargement. These results support the development and evaluation of a noninvasive facial nerve stimulator device as a treatment of ischemic stroke.

Regeneration of long-distance peripheral nerve defects after delayed reconstruction in healthy and diabetic rats is supported by immunomodulatory chitosan nerve guides.

PubMed

Stenberg, Lena; Stößel, Maria; Ronchi, Giulia; Geuna, Stefano; Yin, Yaobin; Mommert, Susanne; Mårtensson, Lisa; Metzen, Jennifer; Grothe, Claudia; Dahlin, Lars B; Haastert-Talini, Kirsten

2017-07-18

Delayed reconstruction of transection or laceration injuries of peripheral nerves is inflicted by a reduced regeneration capacity. Diabetic conditions, more frequently encountered in clinical practice, are known to further impair regeneration in peripheral nerves. Chitosan nerve guides (CNGs) have recently been introduced as a new generation of medical devices for immediate peripheral nerve reconstruction. Here, CNGs were used for 45 days delayed reconstruction of critical length 15 mm rat sciatic nerve defects in either healthy Wistar rats or diabetic Goto-Kakizaki rats; the latter resembling type 2 diabetes. In short and long-term investigations, we comprehensively analyzed the performance of one-chambered hollow CNGs (hCNGs) and two-chambered CNGs (CFeCNGs) in which a chitosan film has been longitudinally introduced. Additionally, we investigated in vitro the immunomodulatory effect provided by the chitosan film. Both types of nerve guides, i.e. hCNGs and CFeCNGs, enabled moderate morphological and functional nerve regeneration after reconstruction that was delayed for 45 days. These positive findings were detectable in generally healthy as well as in diabetic Goto-Kakizaki rats (for the latter only in short-term studies). The regenerative outcome did not reach the degree as recently demonstrated after immediate reconstruction using hCNGs and CFeCNGs. CFeCNG-treatment, however, enabled tissue regrowth in all animals (hCNGs: only in 80% of animals). CFeCNGs did further support with an increased vascularization of the regenerated tissue and an enhanced regrowth of motor axons. One mechanism by which the CFeCNGs potentially support successful regeneration is an immunomodulatory effect induced by the chitosan film itself. Our in vitro results suggest that the pro-regenerative effect of chitosan is related to the differentiation of chitosan-adherent monocytes into pro-healing M2 macrophages. No considerable differences appear for the delayed nerve regeneration

A real-time monitoring system for the facial nerve.

PubMed

Prell, Julian; Rachinger, Jens; Scheller, Christian; Alfieri, Alex; Strauss, Christian; Rampp, Stefan

2010-06-01

Damage to the facial nerve during surgery in the cerebellopontine angle is indicated by A-trains, a specific electromyogram pattern. These A-trains can be quantified by the parameter "traintime," which is reliably correlated with postoperative functional outcome. The system presented was designed to monitor traintime in real-time. A dedicated hardware and software platform for automated continuous analysis of the intraoperative facial nerve electromyogram was specifically designed. The automatic detection of A-trains is performed by a software algorithm for real-time analysis of nonstationary biosignals. The system was evaluated in a series of 30 patients operated on for vestibular schwannoma. A-trains can be detected and measured automatically by the described method for real-time analysis. Traintime is monitored continuously via a graphic display and is shown as an absolute numeric value during the operation. It is an expression of overall, cumulated length of A-trains in a given channel; a high correlation between traintime as measured by real-time analysis and functional outcome immediately after the operation (Spearman correlation coefficient [rho] = 0.664, P < .001) and in long-term outcome (rho = 0.631, P < .001) was observed. Automated real-time analysis of the intraoperative facial nerve electromyogram is the first technique capable of reliable continuous real-time monitoring. It can critically contribute to the estimation of functional outcome during the course of the operative procedure.

Chitin biological absorbable catheters bridging sural nerve grafts transplanted into sciatic nerve defects promote nerve regeneration.

PubMed

Wang, Zhi-Yong; Wang, Jian-Wei; Qin, Li-Hua; Zhang, Wei-Guang; Zhang, Pei-Xun; Jiang, Bao-Guo

2018-06-01

To investigate the efficacy of chitin biological absorbable catheters in a rat model of autologous nerve transplantation. A segment of sciatic nerve was removed to produce a sciatic nerve defect, and the sural nerve was cut from the ipsilateral leg and used as a graft to bridge the defect, with or without use of a chitin biological absorbable catheter surrounding the graft. The number and morphology of regenerating myelinated fibers, nerve conduction velocity, nerve function index, triceps surae muscle morphology, and sensory function were evaluated at 9 and 12 months after surgery. All of the above parameters were improved in rats in which the nerve graft was bridged with chitin biological absorbable catheters compared with rats without catheters. The results of this study indicate that use of chitin biological absorbable catheters to surround sural nerve grafts bridging sciatic nerve defects promotes recovery of structural, motor, and sensory function and improves muscle fiber morphology. © 2018 John Wiley & Sons Ltd.

Assessment of nerve regeneration across nerve allografts treated with tacrolimus.

PubMed

Haisheng, Han; Songjie, Zuo; Xin, Li

2008-01-01

Although regeneration of nerve allotransplant is a major concern in the clinic, there have been few papers quantitatively assessing functional recovery of animals' nerve allografts in the long term. In this study, functional recovery, histopathological study, and immunohistochemistry changes of rat nerve allograft with FK506 were investigated up to 12 weeks without slaughtering. C57 and SD rats were used for transplantation. The donor's nerve was sliced and transplanted into the recipient. The sciatic nerve was epineurally sutured with 10-0 nylon. In total, 30 models of transplantation were performed and divided into 3 groups that were either treated with FK506 or not. Functional recovery of the grafted nerve was serially assessed by the pin click test, walking track analysis and electrophysiological evaluations. A histopathological study and immunohistochemistry study were done in the all of the models. Nerve allografts treated with FK506 have no immune rejection through 12 weeks. Sensibility had similarly improved in both isografts and allografts. There has been no difference in each graft. Walk track analysis demonstrates significant recovery of motor function of the nerve graft. No histological results of difference were found up to 12 weeks in each graft. In the rodent nerve graft model, FK506 prevented nerve allograft rejection across a major histocompatibility barrier. Sensory recovery seems to be superior to motor function. Nerve isograft and allograft treated with FK506 have no significant difference in function recovery, histopathological result, and immunohistochemistry changes.

Optogenetic probing of nerve and muscle function after facial nerve lesion in the mouse whisker system

NASA Astrophysics Data System (ADS)

Bandi, Akhil; Vajtay, Thomas J.; Upadhyay, Aman; Yiantsos, S. Olga; Lee, Christian R.; Margolis, David J.

2018-02-01

Optogenetic modulation of neural circuits has opened new avenues into neuroscience research, allowing the control of cellular activity of genetically specified cell types. Optogenetics is still underdeveloped in the peripheral nervous system, yet there are many applications related to sensorimotor function, pain and nerve injury that would be of great benefit. We recently established a method for non-invasive, transdermal optogenetic stimulation of the facial muscles that control whisker movements in mice (Park et al., 2016, eLife, e14140)1. Here we present results comparing the effects of optogenetic stimulation of whisker movements in mice that express channelrhodopsin-2 (ChR2) selectively in either the facial motor nerve (ChAT-ChR2 mice) or muscle (Emx1-ChR2 or ACTA1-ChR2 mice). We tracked changes in nerve and muscle function before and up to 14 days after nerve transection. Optogenetic 460 nm transdermal stimulation of the distal cut nerve showed that nerve degeneration progresses rapidly over 24 hours. In contrast, the whisker movements evoked by optogenetic muscle stimulation were up-regulated after denervation, including increased maximum protraction amplitude, increased sensitivity to low-intensity stimuli, and more sustained muscle contractions (reduced adaptation). Our results indicate that peripheral optogenetic stimulation is a promising technique for probing the timecourse of functional changes of both nerve and muscle, and holds potential for restoring movement after paralysis induced by nerve damage or motoneuron degeneration.

Cross-face nerve grafting for reanimation of incomplete facial paralysis: quantitative outcomes using the FACIAL CLIMA system and patient satisfaction.

PubMed

Hontanilla, Bernardo; Marre, Diego; Cabello, Alvaro

2014-01-01

Although in most cases Bell palsy resolves spontaneously, approximately one-third of patients will present sequela including facial synkinesis and paresis. Currently, the techniques available for reanimation of these patients include hypoglossal nerve transposition, free muscle transfer, and cross-face nerve grafting (CFNG). Between December 2008 and March 2012, eight patients with incomplete unilateral facial paralysis were reanimated with two-stage CFNG. Gender, age at surgery, etiology of paralysis denervation time, donor and recipient nerves, presence of facial synkinesis, and follow-up were registered. Commissural excursion and velocity and patient satisfaction were evaluated with the FACIAL CLIMA and a questionnaire, respectively. Mean age at surgery was 33.8 ± 11.5 years; mean time of denervation was 96.6 ± 109.8 months. No complications requiring surgery were registered. Follow-up period ranged from 7 to 33 months with a mean of 19 ± 9.7 months. FACIAL CLIMA showed improvement of both commissural excursion and velocity greater than 75% in 4 patients, greater than 50% in 2 patients, and less than 50% in the remaining two patients. Qualitative evaluation revealed a high grade of satisfaction in six patients (75%). Two-stage CFNG is a reliable technique for reanimation of incomplete facial paralysis with a high grade of patient satisfaction. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Corneal subbasal nerve fiber regeneration in myopic patients after laser in situ keratomileusis★

PubMed Central

Deng, Shijing; Wang, Mengmeng; Zhang, Fengju; Sun, Xuguang; Hou, Wenbo; Guo, Ning

2012-01-01

A total of 26 myopic patients (52 eyes) underwent laser in situ keratomileusis. In vivo confocal microscopy revealed that most of the regenerated corneal subbasal nerve fibers in the corneal flap originated from the stump of corneal subbasal nerve fibers outside the ablation zone and extended towards the center of the cornea in all patients. Meanwhile, new fibers were also found to directly regenerate from deep in the stroma in some cases. Approximately 94% of regenerated corneal subbasal nerve fibers (73/78 eyes) regrew vertically into the peripheral central 6-mm circle area 1 month after surgery, 78% (28/36 eyes) grew into the central 3–6 mm area at 2 months, and 23% into the central 3-mm circle area at 3 months. In addition, there was no significant difference in corneal subbasal nerve fiber regenerative capacity between the basic fibroblast growth factor group and the 20% (v/v) deproteinized extract of calf blood group. The majority of corneal subbasal nerve fiber regeneration occurred from the stump of corneal subbasal nerve fibers outside the corneal flap, and the remaining growth occurred deep within the stroma. PMID:25657693

Nerve Regeneration in Conditions of HSV-Infection and an Antiviral Drug Influence.

PubMed

Gumenyuk, Alla; Rybalko, Svetlana; Ryzha, Alona; Savosko, Sergey; Labudzynskyi, Dmytro; Levchuk, Natalia; Chaikovsky, Yuri

2018-05-05

Herpes simplex virus type I (HSV-I) is a latent neuroinfection which can cause focal brain lesion. The role of HSV-infection in nerve regeneration has not been studied so far. The aim of the work was to study sciatic nerve regeneration in the presence of HSV-infection and the influence of an antiviral drug. BALB/c line mice were divided into five groups. Group 1 animals were infected with HSV-I. After resolution of neuroinfection manifestations the sciatic nerve of these animals was crushed. Group 2 mice were administered acyclovir following the same procedures. Groups 3-5 mice served as controls. Thirty days after the operation distal nerve stumps and m.gastrocnemius were studied morphologically and biochemically. Ultrastructural organization of the sciatic nerve in control animals remained intact. Morphometric parameters of the nerves from the experimental groups have not reach control values. However, in the group 1 diameter of nerve fibers was significantly smaller than in the group 2. Both nerve regeneration and m.gastrocnemius reinnervation were confirmed. The muscle hypotrophy was found in groups 1, 2, and 3 (the muscle fibers diameter decreased). Metabolic changes in the muscles of the infected animals (groups 1 and 2) were more pronounced than in control groups 3 and 4. The levels of TBA-active products, conjugated dienes, carbonyl and SH-groups were reduced in m.gastrocnemius of the experimental groups, however no significant difference associated with acyclovir administration was found. HSV-infection is not limited to the local neurodegenerative changes in the CNS but affects regeneration of the injured sciatic nerve. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Low-intensity pulsed ultrasound treatment improved the rate of autograft peripheral nerve regeneration in rat

PubMed Central

Jiang, Wenli; Wang, Yuexiang; Tang, Jie; Peng, Jiang; Wang, Yu; Guo, Quanyi; Guo, Zhiyuan; Li, Pan; Xiao, Bo; Zhang, Jinxing

2016-01-01

Low intensity pulsed ultrasound (LIPUS) has been widely used in clinic for the treatment of repairing pseudarthrosis, bone fractures and of healing in various soft tissues. Some reports indicated that LIPUS accelerated peripheral nerve regeneration including Schwann cells (SCs) and injured nerves. But little is known about its appropriate intensities on autograft nerves. This study was to investigate which intensity of LIPUS improved the regeneration of gold standard postsurgical nerves in experimental rat model. Sprague-Dawley rats were made into 10 mm right side sciatic nerve reversed autologous nerve transplantation and randomly treated with 250 mW/cm2, 500 mW/cm2 or 750 mW/cm2 LIPUS for 2–12 weeks after operation. Functional and pathological results showed that LIPUS of 250 mW/cm2 significantly induced faster rate of axonal regeneration. This suggested that autograft nerve regeneration was improved. PMID:27102358

Role of nitric oxide in the onset of facial nerve palsy by HSV-1 infection.

PubMed

Hato, Naohito; Kohno, Hisashi; Yamada, Hiroyuki; Takahashi, Hirotaka; Gyo, Kiyofumi

2013-12-01

Although herpes simplex virus type 1 (HSV-1) is a causative agent of Bell palsy, the precise mechanism of the paralysis remains unknown. It is necessary to investigate the pathogenesis and treatment of Bell palsy due to HSV-1 infection. This study elucidated the role of nitric oxide (NO) in the incidence of facial nerve paralysis caused by HSV-1 in mice and to evaluate the possible role of edaravone, a free radical scavenger, in preventing the paralysis. Sixty-two mice served as animal models of Bell palsy in this laboratory study conducted at an academic institution. Levels of NO in the facial nerve were measured using high-performance liquid chromatography and absorption photometry. The incidence of facial palsy was assessed following administration of edaravone immediately after HSV-1 inoculation and daily for 11 days thereafter. The ratio of NO (inoculated side to control side) and incidence of facial palsy. RESULTS Before the onset of facial palsy, no substantial difference in the NO level was noted between the HSV-1-inoculated side and the control side. When facial palsy occurred, usually at 7 days after inoculation, the NO level was significantly higher on the inoculated side than on the control side. Following recovery from the palsy, the high NO level of the inoculated side decreased. No increase in the NO level was observed in animals without transient facial palsy. When edaravone was administered, the incidence of facial palsy decreased significantly. These findings suggest that NO produced by inducible NO synthase in the facial nerve plays an important role in the onset of facial palsy caused by HSV-1 infection, which is considered a causative virus of Bell palsy. Hato and colleagues elucidate the role of nitric oxide in HSV-1–related facial nerve paralysis in mice and evaluate the role of edaravone, a free radical scavenger, in preventing the paralysis.

Nerve Regeneration in the Peripheral Nervous System versus the Central Nervous System and the Relevance to Speech and Hearing after Nerve Injuries

ERIC Educational Resources Information Center

Gordon, Tessa; Gordon, Karen

2010-01-01

Schwann cells normally form myelin sheaths around axons in the peripheral nervous system (PNS) and support nerve regeneration after nerve injury. In contrast, nerve regeneration in the central nervous system (CNS) is not supported by the myelinating cells known as oligodendrocytes. We have found that: 1) low frequency electrical stimulation can be…

Masseteric nerve for reanimation of the smile in short-term facial paralysis.

PubMed

Hontanilla, Bernardo; Marre, Diego; Cabello, Alvaro

2014-02-01

Our aim was to describe our experience with the masseteric nerve in the reanimation of short term facial paralysis. We present our outcomes using a quantitative measurement system and discuss its advantages and disadvantages. Between 2000 and 2012, 23 patients had their facial paralysis reanimated by masseteric-facial coaptation. All patients are presented with complete unilateral paralysis. Their background, the aetiology of the paralysis, and the surgical details were recorded. A retrospective study of movement analysis was made using an automatic optical system (Facial Clima). Commissural excursion and commissural contraction velocity were also recorded. The mean age at reanimation was 43(8) years. The aetiology of the facial paralysis included acoustic neurinoma, fracture of the skull base, schwannoma of the facial nerve, resection of a cholesteatoma, and varicella zoster infection. The mean time duration of facial paralysis was 16(5) months. Follow-up was more than 2 years in all patients except 1 in whom it was 12 months. The mean duration to recovery of tone (as reported by the patient) was 67(11) days. Postoperative commissural excursion was 8(4)mm for the reanimated side and 8(3)mm for the healthy side (p=0.4). Likewise, commissural contraction velocity was 38(10)mm/s for the reanimated side and 43(12)mm/s for the healthy side (p=0.23). Mean percentage of recovery was 92(5)mm for commissural excursion and 79(15)mm/s for commissural contraction velocity. Masseteric nerve transposition is a reliable and reproducible option for the reanimation of short term facial paralysis with reduced donor site morbidity and good symmetry with the opposite healthy side. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

In vivo assessment of peripheral nerve regeneration by diffusion tensor imaging.

PubMed

Morisaki, Shinsuke; Kawai, Yuko; Umeda, Masahiro; Nishi, Mayumi; Oda, Ryo; Fujiwara, Hiroyoshi; Yamada, Kei; Higuchi, Toshihiro; Tanaka, Chuzo; Kawata, Mitsuhiro; Kubo, Toshikazu

2011-03-01

To evaluate the sensitivity of diffusion tensor imaging (DTI) in assessing peripheral nerve regeneration in vivo. We assessed the changes in the DTI parameters and histological analyses after nerve injury to examine degeneration and regeneration in the rat sciatic nerves. For magnetic resonance imaging (MRI), 16 rats were randomly divided into two groups: group P (permanently crushed; n = 7) and group T (temporally crushed; n = 9). Serial MRI of the right leg was performed before the operation, and then performed at the timepoints of 1, 2, 3, and 4 weeks after the crush injury. The changes in fractional anisotropy (FA), axial diffusivity (λ(∥)), and radial diffusivity (λ(⟂)) were quantified. For histological analyses, the number of axons and the myelinated axon areas were quantified. Decreased FA and increased λ(⟂) were observed in the degenerative phase, and increased FA and decreased λ(⟂) were observed in the regenerative phase. The changes in FA and λ(⟂) were strongly correlated with histological changes, including axonal and myelin regeneration. DTI parameters, especially λ(⟂) , can be good indicators for peripheral nerve regeneration and can be applied as noninvasive diagnostic tools for a variety of neurological diseases. Copyright © 2011 Wiley-Liss, Inc.

Sciatic nerve regeneration in rats subjected to ketogenic diet.

PubMed

Liśkiewicz, Arkadiusz; Właszczuk, Adam; Gendosz, Daria; Larysz-Brysz, Magdalena; Kapustka, Bartosz; Łączyński, Mariusz; Lewin-Kowalik, Joanna; Jędrzejowska-Szypułka, Halina

2016-01-01

Ketogenic diet (KD) is a high-fat-content diet with insufficiency of carbohydrates that induces ketogenesis. Besides its anticonvulsant properties, many studies have shown its neuroprotective effect in central nervous system, but its influence on peripheral nervous system has not been studied yet. We examined the influence of KD on regeneration of peripheral nerves in adult rats. Fifty one rats were divided into three experimental (n = 15) and one control (n = 6) groups. Right sciatic nerve was crushed and animals were kept on standard (ST group) or ketogenic diet, the latter was introduced 3 weeks before (KDB group) or on the day of surgery (KDA group). Functional (CatWalk) tests were performed once a week, and morphometric (fiber density, axon diameter, and myelin thickness) analysis of the nerves was made after 6 weeks. Body weight and blood ketone bodies level were estimated at the beginning and the end of experiment. Functional analysis showed no differences between groups. Morphometric evaluation showed most similarities to the healthy (uncrushed) nerves in KDB group. Nerves in ST group differed mostly from all other groups. Ketone bodies were elevated in both KD groups, while post-surgery animals' body weight was lower as compared to ST group. Regeneration of sciatic nerves was improved in KD - preconditioned rats. These results suggest a neuroprotective effect of KD on peripheral nerves.

Anatomical study of the facial nerve canal in comparison to the site of the lesion in Bell's palsy.

PubMed

Dawidowsky, Krsto; Branica, Srećko; Batelja, Lovorka; Dawidowsky, Barbara; Kovać-Bilić, Lana; Simunić-Veselić, Anamarija

2011-03-01

The term Bell's palsy is used for the peripheral paresis of the facial nerve and is of unknown origin. Many studies have been performed to find the cause of the disease, but none has given certain evidence of the etiology. However, the majority of investigators agree that the pathophysiology of the palsy starts with the edema of the facial nerve and consequent entrapment of the nerve in the narrow facial canal in the temporal bone. In this study the authors wanted to find why the majority of the paresis are suprastapedial, i.e. why the entrapment of the nerve mainly occurs in the proximal part of the canal. For this reason they carried out anatomical measurements of the facial canal diameter in 12 temporal bones. By use of a computer program which measures the cross-sectional area from the diameter, they proved that the width of the canal is smaller at its proximal part. Since the nerve is thicker at that point because it contains more nerve fibers, the authors conclude that the discrepancy between the nerve diameter and the surrounding bony walls in the suprastapedial part of the of the canal would, in cases of a swollen nerve after inflammation, cause the facial palsy.

A forgotten facial nerve tumour: granular cell tumour of the parotid and its implications for treatment.

PubMed

Lerut, B; Vosbeck, J; Linder, T E

2011-04-01

We present a rare case of a facial nerve granular cell tumour in the right parotid gland, in a 10-year-old boy. A parotid or neurogenic tumour was suspected, based on magnetic resonance imaging. Intra-operatively, strong adhesions to surrounding structures were found, and a midfacial nerve branch had to be sacrificed for complete tumour removal. Recent reports verify that granular cell tumours arise from Schwann cells of peripheral nerve branches. The rarity of this tumour within the parotid gland, its origin from peripheral nerves, its sometimes misleading imaging characteristics, and its rare presentation with facial weakness and pain all have considerable implications on the surgical strategy and pre-operative counselling. Fine needle aspiration cytology may confirm the neurogenic origin of this lesion. When resecting the tumour, the surgeon must anticipate strong adherence to the facial nerve and be prepared to graft, or sacrifice, certain branches of this nerve.

The beneficial effect of genetically engineered Schwann cells with enhanced motility in peripheral nerve regeneration: review.

PubMed

Gravvanis, A I; Lavdas, A A; Papalois, A; Tsoutsos, D A; Matsas, R

2007-01-01

The importance of Schwann cells in promoting nerve regeneration across a conduit has been extensively reported in the literature, and Schwann cell motility has been acknowledged as a prerequisite for myelination of the peripheral nervous system during regeneration after injury. Review of recent literature and retrospective analysis of our studies with genetically modified Schwann Cells with increased motility in order to identify the underlying mechanism of action and outline the future trends in peripheral nerve repair. Schwann cell transduction with the pREV-retrovirus, for expression of Sialyl-Transferase-X, resulting in conferring Polysialyl-residues (PSA) on NCAM, increases their motility in-vitro and ensures nerve regeneration through silicone tubes after end-to-side neurorraphy in the rat sciatic nerve model, thus significantly promoting fiber maturation and functional outcome. An artificial nerve graft consisting of a type I collagen tube lined with the genetically modified Schwann cells with increased motility, used to bridge a defect in end-to-end fashion in the rat sciatic nerve model, was shown to promote nerve regeneration to a level equal to that of a nerve autograft. The use of genetically engineered Schwann cells with enhanced motility for grafting endoneural tubes promotes axonal regeneration, by virtue of the interaction of the transplanted cells with regenerating axonal growth cones as well as via the recruitment of endogenous Schwann cells. It is envisaged that mixed populations of Schwann cells, expressing PSA and one or more trophic factors, might further enhance the regenerating and remyelinating potential of the lesioned nerves.

Role of Schwann cells in the regeneration of penile and peripheral nerves

PubMed Central

Wang, Lin; Sanford, Melissa T; Xin, Zhongcheng; Lin, Guiting; Lue, Tom F

2015-01-01

Schwann cells (SCs) are the principal glia of the peripheral nervous system. The end point of SC development is the formation of myelinating and nonmyelinating cells which ensheath large and small diameter axons, respectively. They play an important role in axon regeneration after injury, including cavernous nerve injury that leads to erectile dysfunction (ED). Despite improvement in radical prostatectomy surgical techniques, many patients still suffer from ED postoperatively as surgical trauma causes traction injuries and local inflammatory changes in the neuronal microenvironment of the autonomic fibers innervating the penis resulting in pathophysiological alterations in the end organ. The aim of this review is to summarize contemporary evidence regarding: (1) the origin and development of SCs in the peripheral and penile nerve system; (2) Wallerian degeneration and SC plastic change following peripheral and penile nerve injury; (3) how SCs promote peripheral and penile nerve regeneration by secreting neurotrophic factors; (4) and strategies targeting SCs to accelerate peripheral nerve regeneration. We searched PubMed for articles related to these topics in both animal models and human research and found numerous studies suggesting that SCs could be a novel target for treatment of nerve injury-induced ED. PMID:25999359

Management of the Facial Nerve in Lateral Skull Base Surgery Analytic Retrospective Study

PubMed Central

El Shazly, Mohamed A.; Mokbel, Mahmoud A.M.; Elbadry, Amr A.; Badran, Hatem S.

2011-01-01

Background: Surgical approaches to the jugular foramen are often complex and lengthy procedures associated with significant morbidity based on the anatomic and tumor characteristics. In addition to the risk of intra-operative hemorrhage from vascular tumors, lower cranial nerves deficits are frequently increased after intra-operative manipulation. Accordingly, modifications in the surgical techniques have been developed to minimize these risks. Preoperative embolization and intra-operative ligation of the external carotid artery have decreased the intraoperative blood loss. Accurate identification and exposure of the cranial nerves extracranially allows for their preservation during tumor resection. The modification of facial nerve mobilization provides widened infratemporal exposure with less postoperative facial weakness. The ideal approach should enable complete, one stage tumor resection with excellent infratemporal and posterior fossa exposure and would not aggravate or cause neurologic deficit. The aim of this study is to present our experience in handling jugular foramen lesions (mainly glomus jugulare) without the need for anterior facial nerve transposition. Methods: In this series we present our experience in Kasr ElEini University hospital (Cairo—Egypt) in handling 36 patients with jugular foramen lesions over a period of 20 years where the previously mentioned preoperative and operative rules were followed. The clinical status, operative technique and postoperative care and outcome are detailed and analyzed in relation to the outcome. Results: Complete cure without complications was achieved in four cases of congenital cholesteatoma and four cases with class B glomus. In advanced cases of glomus jugulare (28 patients) (C and D stages) complete cure was achieved in 21 of them (75%). The operative complications were also related to this group of 28 patients, in the form of facial paralysis in 20 of them (55.6%) and symptomatic vagal paralysis in 18 of

Management of the facial nerve in lateral skull base surgery analytic retrospective study.

PubMed

El Shazly, Mohamed A; Mokbel, Mahmoud A M; Elbadry, Amr A; Badran, Hatem S

2011-01-01

Surgical approaches to the jugular foramen are often complex and lengthy procedures associated with significant morbidity based on the anatomic and tumor characteristics. In addition to the risk of intra-operative hemorrhage from vascular tumors, lower cranial nerves deficits are frequently increased after intra-operative manipulation. Accordingly, modifications in the surgical techniques have been developed to minimize these risks. Preoperative embolization and intra-operative ligation of the external carotid artery have decreased the intraoperative blood loss. Accurate identification and exposure of the cranial nerves extracranially allows for their preservation during tumor resection. The modification of facial nerve mobilization provides widened infratemporal exposure with less postoperative facial weakness. The ideal approach should enable complete, one stage tumor resection with excellent infratemporal and posterior fossa exposure and would not aggravate or cause neurologic deficit. The aim of this study is to present our experience in handling jugular foramen lesions (mainly glomus jugulare) without the need for anterior facial nerve transposition. In this series we present our experience in Kasr ElEini University hospital (Cairo-Egypt) in handling 36 patients with jugular foramen lesions over a period of 20 years where the previously mentioned preoperative and operative rules were followed. The clinical status, operative technique and postoperative care and outcome are detailed and analyzed in relation to the outcome. Complete cure without complications was achieved in four cases of congenital cholesteatoma and four cases with class B glomus. In advanced cases of glomus jugulare (28 patients) (C and D stages) complete cure was achieved in 21 of them (75%). The operative complications were also related to this group of 28 patients, in the form of facial paralysis in 20 of them (55.6%) and symptomatic vagal paralysis in 18 of them (50%). Total anterior

Nerve regeneration using tubular scaffolds from biodegradable polyurethane.

PubMed

Hausner, T; Schmidhammer, R; Zandieh, S; Hopf, R; Schultz, A; Gogolewski, S; Hertz, H; Redl, H

2007-01-01

In severe nerve lesion, nerve defects and in brachial plexus reconstruction, autologous nerve grafting is the golden standard. Although, nerve grafting technique is the best available approach a major disadvantages exists: there is a limited source of autologous nerve grafts. This study presents data on the use of tubular scaffolds with uniaxial pore orientation from experimental biodegradable polyurethanes coated with fibrin sealant to regenerate a 8 mm resected segment of rat sciatic nerve. Tubular scaffolds: prepared by extrusion of the polymer solution in DMF into water coagulation bath. The polymer used for the preparation of tubular scaffolds was a biodegradable polyurethane based on hexamethylene diisocyanate, poly(epsilon-caprolactone) and dianhydro-D-sorbitol. EXPERIMENTAL MODEL: Eighteen Sprague Dawley rats underwent mid-thigh sciatic nerve transection and were randomly assigned to two experimental groups with immediate repair: (1) tubular scaffold, (2) 180 degrees rotated sciatic nerve segment (control). Serial functional measurements (toe spread test, placing tests) were performed weekly from 3rd to 12th week after nerve repair. On week 12, electrophysiological assessment was performed. Sciatic nerve and scaffold/nerve grafts were harvested for histomorphometric analysis. Collagenic connective tissue, Schwann cells and axons were evaluated in the proximal nerve stump, the scaffold/nerve graft and the distal nerve stump. The implants have uniaxially-oriented pore structure with a pore size in the range of 2 micorm (the pore wall) and 75 x 700 microm (elongated pores in the implant lumen). The skin of the tubular implants was nonporous. Animals which underwent repair with tubular scaffolds of biodegradable polyurethanes coated with diluted fibrin sealant had no significant functional differences compared with the nerve graft group. Control group resulted in a trend-wise better electrophysiological recovery but did not show statistically significant

Functional evaluation of peripheral nerve regeneration and target reinnervation in animal models: a critical overview.

PubMed

Navarro, Xavier

2016-02-01

Peripheral nerve injuries usually lead to severe loss of motor, sensory and autonomic functions in the patients. Due to the complex requirements for adequate axonal regeneration, functional recovery is often poorly achieved. Experimental models are useful to investigate the mechanisms related to axonal regeneration and tissue reinnervation, and to test new therapeutic strategies to improve functional recovery. Therefore, objective and reliable evaluation methods should be applied for the assessment of regeneration and function restitution after nerve injury in animal models. This review gives an overview of the most useful methods to assess nerve regeneration, target reinnervation and recovery of complex sensory and motor functions, their values and limitations. The selection of methods has to be adequate to the main objective of the research study, either enhancement of axonal regeneration, improving regeneration and reinnervation of target organs by different types of nerve fibres, or increasing recovery of complex sensory and motor functions. It is generally recommended to use more than one functional method for each purpose, and also to perform morphological studies of the injured nerve and the reinnervated targets. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

The effect of methylprednisolone on facial nerve paralysis with different etiologies.

PubMed

Yildirim, Mehmet Akif; Karlidag, Turgut; Akpolat, Nusret; Kaygusuz, Irfan; Keles, Erol; Yalcin, Sinasi; Akyigit, Abdulvahap

2015-05-01

The objective of this study was to evaluate the effectiveness of methylprednisolone (MP) in models of facial nerve paralysis obtained by nerve section, compression, or inoculation with herpes simplex virus (HSV). Experimental controlled animal study. Tertiary referral center. A total of 30 female New Zealand rabbits weighing 1200-3000 g were used for the study. They were randomly assigned to one of 6 groups of 5 animals each. A nerve section injury was realized in Groups 1a (section and MP) and 1b (section, control) rabbits. A compression-type injury was inflicted to rabbits in Groups 2a (compression and MP) and 2b (compression, control). As for animals in Groups 3a (Type 1 HSV and MP) and 3b (Type 1 HSV, controls), facial nerve paralysis resulting from viral infection was obtained. Animals in the 3 treatment groups, designated with the letter "a", were administered MP, 1 mg/kg/d, whereas those in control groups "b" received 1 mL normal saline, both during 3 weeks. All subjects were followed up for 2 months. At the end of this period, all animals had the buccal branch of the facial nerve excised on the operated side. Semi-thin sections of these specimens were evaluated under light microscopy for the following: perineural fibrosis, increase in collagen fibers, myelin degeneration, axonal degeneration, Schwann cell proliferation, and edema. No significant difference was observed (P > 0.05) between the MP treatment group and the control group with regard to perineural fibrosis, increase in collagen fibers, myelin degeneration, axonal degeneration, edema, or Schwann cell proliferation. In the group with a compressive lesion (Group 2), controls were no different from MP-treated animals as to perineural fibrosis, increase in collagen fibers, or Schwann cell proliferation, whereas axonal degeneration, myelin degeneration, and edema were significantly higher (P < 0.05) in the control group. When comparing the treatment and control groups among the animals inoculated with

Microsurgical dissection of facial nerve in parotidectomy: a discussion of techniques and long-term results

PubMed Central

Nicoli, Fabio; D’Ambrosia, Christopher; Lazzeri, Davide; Orfaniotis, Georgios; Ciudad, Pedro; Maruccia, Michele; Shiun, Li Tzong; Sacak, Bulent; Chen, Shih-Heng

2017-01-01

Background Parotidectomy has well-documented post-operative complications. Dissection of the facial nerve branches can be challenging even under loupe magnification, and partial, or complete injury of the nerve branches can occur during surgery. To reduce this risk and the associated complications, we propose a number of microsurgical best practices, which can be performed during parotidectomy. Methods A retrospective survey was conducted on 109 patients (45 males and 64 females, average age 46.2 years, range of 6 to 74 years) who underwent parotidectomy in two different institutions. Results Our data showed no permanent injury to the facial nerve, and 17% of neuroapraxia that had resolved with time. Post-operative complications have occurred in 33 cases (30% rate). In the superficial parotidectomy cohort (78 patients), the number of complications was 17 (21%). In the total parotidectomy cohort (31 patients), the number of complications was 16 (51%). Conclusions Based on our results, we believe that the use of microsurgical techniques during parotidectomy may represent a useful tool in improving accuracy and minimising local tissue trauma that can affect nerve recovery. This is particularly true in situations such as tumor recurrence, tissue fibrosis or in case of sizeable tumors around the facial nerve branches. We believe that the decreased risk of facial nerve post-operative symptoms outweigh the disadvantage of increased operative time of this procedure. PMID:28861369

[Relationship between Work Ⅱ type of congenital first branchial cleft anomaly and facial nerve and surgical strategies].

PubMed

Zhang, B; Chen, L S; Huang, S L; Liang, L; Gong, X X; Wu, P N; Zhang, S Y; Luo, X N; Zhan, J D; Sheng, X L; Lu, Z M

2017-10-07

Objective: To investigate the relationship between Work Ⅱ type of congenital first branchial cleft anomaly (CFBCA) and facial nerve and discuss surgical strategies. Methods: Retrospective analysis of 37 patients with CFBCA who were treated from May 2005 to September 2016. Among 37 cases with CFBCA, 12 males and 25 females; 24 in the left and 13 in the right; the age at diagnosis was from 1 to 76 ( years, with a median age of 20, 24 cases with age of 18 years or less and 13 with age more than 18 years; duration of disease ranged from 1 to 10 years (median of 6 years); 4 cases were recurren after fistula resection. According to the classification of Olsen, all 37 cases were non-cyst (sinus or fistula). External fistula located over the mandibular angle in 28 (75.7%) cases and below the angle in 9 (24.3%) cases. Results: Surgeries were performed successfully in all the 37 cases. It was found that lesions located at anterior of the facial nerve in 13 (35.1%) cases, coursed between the branches in 3 cases (8.1%), and lied in the deep of the facial nerve in 21 (56.8%) cases. CFBCA in female with external fistula below mandibular angle and membranous band was more likely to lie deep of the facial nerve than in male with external fistula over the mandibular angle but without myringeal web. Conclusions: CFBCA in female patients with a external fistula located below the mandibular angle, non-cyst of Olsen or a myringeal web is more likely to lie deep of the facial nerve. Surgeons should particularly take care of the protection of facial nerve in these patients, if necessary, facial nerve monitoring technology can be used during surgery to complete resection of lesions.

Emerging nanotechnology approaches in tissue engineering for peripheral nerve regeneration.

PubMed

Cunha, Carla; Panseri, Silvia; Antonini, Stefania

2011-02-01

Effective nerve regeneration and functional recovery subsequent to peripheral nerve injury is still a clinical challenge. Autologous nerve graft transplantation is a feasible treatment in several clinical cases, but it is limited by donor site morbidity and insufficient donor tissue, impairing complete functional recovery. Tissue engineering has introduced innovative approaches to promote and guide peripheral nerve regeneration by using biomimetic conduits creating favorable microenvironments for nervous ingrowth, but despite the development of a plethora of nerve prostheses, few approaches have as yet entered the clinic. Promising strategies using nanotechnology have recently been proposed, such as the use of scaffolds with functionalized cell-binding domains, the use of guidance channels with cell-scale internally oriented fibers, and the possibility of sustained release of neurotrophic factors. This review addresses the fabrication, advantages, drawbacks, and results achieved by the most recent nanotechnology approaches in view of future solutions for peripheral nerve repair. Peripheral nerve repair strategies are very limited despite numerous advances on the field of neurosciences and regenerative medicine. This review discusses nanotechnology based strategies including scaffolds with functionalized cell binding domains, the use of guidance channels, and the potential use of sustained release neurotropic factors. Copyright © 2011 Elsevier Inc. All rights reserved.

Ursolic acid induces neural regeneration after sciatic nerve injury

PubMed Central

Liu, Biao; Liu, Yan; Yang, Guang; Xu, Zemin; Chen, Jiajun

2013-01-01

In this study, we aimed to explore the role of ursolic acid in the neural regeneration of the injured sciatic nerve. BALB/c mice were used to establish models of sciatic nerve injury through unilateral sciatic nerve complete transection and microscopic anastomosis at 0.5 cm below the ischial tube-rosity. The successfully generated model mice were treated with 10, 5, or 2.5 mg/kg ursolic acid via intraperitoneal injection. Enzyme-linked immunosorbent assay results showed that serum S100 protein expression level gradually increased at 1–4 weeks after sciatic nerve injury, and significantly decreased at 8 weeks. As such, ursolic acid has the capacity to significantly increase S100 protein expression levels. Real-time quantitative PCR showed that S100 mRNA expression in the L4–6 segments on the injury side was increased after ursolic acid treatment. In addition, the muscular mass index in the soleus muscle was also increased in mice treated with ursolic acid. Toluidine blue staining revealed that the quantity and average diameter of myelinated nerve fibers in the injured sciatic nerve were significantly increased after treatment with ursolic acid. 10 and 5 mg/kg of ursolic acid produced stronger effects than 2.5 mg/kg of ursolic acid. Our findings indicate that ursolic acid can dose-dependently increase S100 expression and promote neural regeneration in BALB/c mice following sciatic nerve injury. PMID:25206561

[Myxoma of the mastoid with destruction of the facial nerve (author's transl)].

PubMed

Neiger, M

1978-10-01

A case of Myxoma of the mastoid with initial facial spasme followed by palsy of the nerve is reported. After removing the tumor the nerve has been reconstructed from the secound knee until the stylomastoid foramen. The probable origine of the tumor is discussed.

Patterns of anomalies of structures of the middle ear and the facial nerve as revealed in newborn temporal bones.

PubMed

Tóth, Miklós; Sirirattanapan, Jarinratn; Mann, Wolf

2013-08-01

The purpose of this study is to offer new data about facial nerve malformations in the tympanic cavity. Prospective anatomic study of newborns to demonstrate the submacroscopic anatomy of the intratympanic facial nerve and its surrounding structures by malformations. Step-by-step microdissection of 12 newborn temporal bones and histologic evaluation of 4 middle ears showing multiple malformations. Four of 12 temporal bones presented malformation in the middle ear. All 4 temporal bones showed developmental failures of the stapes, and 3 of them had malposition of the tympanic portion of the facial nerve. In 3 cases, there was an oval window atresia, and in 1 case, the rim of the oval window was not ossified and was positioned medial to the stapes. Malformation or displacement of the stapes can be an indirect sign for facial nerve malformation. The most common site for facial nerve malformation is the tympanic portion. The tympanic segment of the nerve is devoid of bony covering in association with these anomalies of the stapes.

Peripheral facial nerve lesions induce changes in the firing properties of primary motor cortex layer 5 pyramidal cells.

PubMed

Múnera, A; Cuestas, D M; Troncoso, J

2012-10-25

Facial nerve lesions elicit long-lasting changes in vibrissal primary motor cortex (M1) muscular representation in rodents. Reorganization of cortical representation has been attributed to potentiation of preexisting horizontal connections coming from neighboring muscle representation. However, changes in layer 5 pyramidal neuron activity induced by facial nerve lesion have not yet been explored. To do so, the effect of irreversible facial nerve injury on electrophysiological properties of layer 5 pyramidal neurons was characterized. Twenty-four adult male Wistar rats were randomly subjected to two experimental treatments: either surgical transection of mandibular and buccal branches of the facial nerve (n=18) or sham surgery (n=6). Unitary and population activity of vibrissal M1 layer 5 pyramidal neurons recorded in vivo under general anesthesia was compared between sham-operated and facial nerve-injured animals. Injured animals were allowed either one (n=6), three (n=6), or five (n=6) weeks recovery before recording in order to characterize the evolution of changes in electrophysiological activity. As compared to control, facial nerve-injured animals displayed the following sustained and significant changes in spontaneous activity: increased basal firing frequency, decreased spike-associated local field oscillation amplitude, and decreased spontaneous theta burst firing frequency. Significant changes in evoked-activity with whisker pad stimulation included: increased short latency population spike amplitude, decreased long latency population oscillations amplitude and frequency, and decreased peak frequency during evoked single-unit burst firing. Taken together, such changes demonstrate that peripheral facial nerve lesions induce robust and sustained changes of layer 5 pyramidal neurons in vibrissal motor cortex. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Facial nerve palsy after reactivation of herpes simplex virus type 1 in diabetic mice.

PubMed

Esaki, Shinichi; Yamano, Koji; Katsumi, Sachiyo; Minakata, Toshiya; Murakami, Shingo

2015-04-01

Bell's palsy is highly associated with diabetes mellitus (DM). Either the reactivation of herpes simplex virus type 1 (HSV-1) or diabetic mononeuropathy has been proposed to cause the facial paralysis observed in DM patients. However, distinguishing whether the facial palsy is caused by herpetic neuritis or diabetic mononeuropathy is difficult. We previously reported that facial paralysis was aggravated in DM mice after HSV-1 inoculation of the murine auricle. In the current study, we induced HSV-1 reactivation by an auricular scratch following DM induction with streptozotocin (STZ). Controlled animal study. Diabetes mellitus was induced with streptozotocin injection in only mice that developed transient facial nerve paralysis with HSV-1. Recurrent facial palsy was induced after HSV-1 reactivation by auricular scratch. After DM induction, the number of cluster of differentiation 3 (CD3)(+) T cells decreased by 70% in the DM mice, and facial nerve palsy recurred in 13% of the DM mice. Herpes simplex virus type 1 deoxyribonucleic acid (DNA) was detected in the facial nerve of all of the DM mice with palsy, and HSV-1 capsids were found in the geniculate ganglion using electron microscopy. Herpes simplex virus type 1 DNA was also found in some of the DM mice without palsy, which suggested the subclinical reactivation of HSV-1. These results suggested that HSV-1 reactivation in the geniculate ganglion may be the main causative factor of the increased incidence of facial paralysis in DM patients. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Assessment of the cochlear nerve to facial nerve size ratio using MR multiplanar reconstruction of the internal auditory canal in patients presenting with acquired long-standing hearing loss

PubMed Central

Hey, Constanze; Shaaban, Mohamed S; Elabd, Amr M; Hassan, Hebatallah H M; Gruber-Rouh, Tatjana; Kaltenbach, Benjamin; Harth, Marc; Ackermann, Hanns; Stöver, Timo; Vogl, Thomas J; Nour-Eldin, Nour-Eldin A

2017-01-01

Objective: To test using the facial nerve as a reference for assessment of the cochlear nerve size in patients with acquired long-standing sensorineural hearing loss (SNHL) using MRI multiplanar reconstruction. Methods: The study was retrospectively performed on 86 patients. Group 1 (study group, n = 53) with bilateral long-standing SNHL. Group 2 (control group, n = 33) without hearing loss. The nerve size was measured by drawing a region of interest around the cross-sectional circumference of the nerve in multiplanar reconstruction images. Results: No significant correlation was noted between the cochlear nerve and facial nerve size, and the patient's age, gender and weight (p > 0.05). In Group 1, the mean ratio of the cochlear to facial nerve size was 0.99 ± 0.30 (range: 0.52–1.86) and 1.12 ± 0.35 (range: 0.34–2.3) for the right and left sides, respectively. In Group 2, it was 1.18 ± 0.23 (range: 0.78–1.71) and 1.25 ± 0.25 (range: 0.85–1.94) for the right and left sides, respectively. The cochlear nerve size was statistically (p = 0.0004) smaller in Group 1 than in Group 2. Conclusion: The cochlear nerve size and the cochlear to facial nerve size ratio are significantly smaller in patients with acquired long-standing SNHL. Advances in knowledge: The facial nerve can be used as a reference for assessment of the cochlear nerve in patients with acquired long-standing SNHL. PMID:28368665

Regulation of dorso‐ventral polarity by the nerve cord during annelid regeneration: A review of experimental evidence

PubMed Central

Boilly‐Marer, Yolande; Bely, Alexandra E.

2017-01-01

Abstract An important goal for understanding regeneration is determining how polarity is conferred to the regenerate. Here we review findings in two groups of polychaete annelids that implicate the ventral nerve cord in assigning dorso‐ventral polarity, and specifically ventral identity, to the regenerate. In nereids, surgical manipulations indicate that parapodia develop where dorsal and ventral body wall territories contact. Without a nerve cord at the wound site, the regenerate differentiates no evident polarity (with no parapodia) and only dorsal identity, while with two nerve cords the regenerate develops a twinned dorso‐ventral axis (with four parapodia per segment instead of the normal two). In sabellids, a striking natural dorso‐ventral inversion in parapodial morphology occurs along the body axis and this inversion is morphologically correlated with the position of the nerve cord. Parapodial inversion also occurs in segments in which the nerve cord has been removed, even without any segment amputation. Together, these data strongly support a role for the nerve cord in annelid dorso‐ventral pattern regulation, with the nerve cord conferring ventral identity. PMID:28616245

Development of biomaterial scaffold for nerve tissue engineering: Biomaterial mediated neural regeneration

PubMed Central

2009-01-01

Neural tissue repair and regeneration strategies have received a great deal of attention because it directly affects the quality of the patient's life. There are many scientific challenges to regenerate nerve while using conventional autologous nerve grafts and from the newly developed therapeutic strategies for the reconstruction of damaged nerves. Recent advancements in nerve regeneration have involved the application of tissue engineering principles and this has evolved a new perspective to neural therapy. The success of neural tissue engineering is mainly based on the regulation of cell behavior and tissue progression through the development of a synthetic scaffold that is analogous to the natural extracellular matrix and can support three-dimensional cell cultures. As the natural extracellular matrix provides an ideal environment for topographical, electrical and chemical cues to the adhesion and proliferation of neural cells, there exists a need to develop a synthetic scaffold that would be biocompatible, immunologically inert, conducting, biodegradable, and infection-resistant biomaterial to support neurite outgrowth. This review outlines the rationale for effective neural tissue engineering through the use of suitable biomaterials and scaffolding techniques for fabrication of a construct that would allow the neurons to adhere, proliferate and eventually form nerves. PMID:19939265

Surgical and conservative methods for restoring impaired motor function - facial nerve, spinal accessory nerve, hypoglossal nerve (not including vagal nerve or swallowing)

PubMed Central

Laskawi, R.; Rohrbach, S.

2005-01-01

The present review gives a survey of rehabilitative measures for disorders of the motor function of the mimetic muscles (facial nerve), and muscles innervated by the spinal accessory and hypoglossal nerves. The dysfunction can present either as paralysis or hyperkinesis (hyperkinesia). Conservative and surgical treatment options aimed at restoring normal motor function and correcting the movement disorders are described. Static reanimation techniques are not dealt with. The final section describes the use of botulinum toxin in the therapy of dysphagia. PMID:22073058

Evidence Suggesting that the Buccal and Zygomatic Branches of the Facial Nerve May Contain Parasympathetic Secretomotor Fibers to the Parotid Gland by Means of Communications from the Auriculotemporal Nerve.

PubMed

Tansatit, Tanvaa; Apinuntrum, Prawit; Phetudom, Thavorn

2015-12-01

The auriculotemporal nerve is one of the peripheral nerves that communicates with the facial nerve. However, the function of these communications is poorly understood. Details of how these communications form and connect with each other are still unclear. In addition, a reliable anatomical landmark for locating these communications during surgery has not been sufficiently described. Microdissection was performed on 20 lateral hemifaces of 10 soft-embalmed cadavers to investigate facial-auriculotemporal nerve communications with emphasis on determining their function. The auriculotemporal nerve was identified in the retromandibular space and traced towards its terminations. The communicating branches were followed and the anatomical relationships to surrounding structures observed. The auriculotemporal nerve is suspended above the maxillary artery in the dense retromandibular fascia behind the mandibular ramus. It forms a knot and fans out, providing multiple branches in all directions in the sagittal plane. Inferiorly, it connects the maxillary periarterial plexus, while minute branches supply the temporomandibular joint anteriorly. The larger branches mainly communicate with the branches of the temporofacial division of the facial nerve, and the auricular branches enter the fascia of the auricular cartilage posteriorly. The temporal branches and occasionally the zygomatic branches arise superiorly to distribute within the temporoparietal fascia. The auriculotemporal nerve forms the parotid retromandibular plexus through two types of communication. It sends one to three branches to join the zygomatic and buccal branches of the facial nerve at the branching area of the temporofacial division. It also communicates with the periarterial plexus of the superficial temporal and maxillary arteries. This plexus continues anteriorly along the branches of the facial nerve and the periarterial plexus of the transverse facial artery as the parotid periductal autonomic plexus

Stimulating effect of thyroid hormones in peripheral nerve regeneration: research history and future direction toward clinical therapy

PubMed Central

Barakat-Walter, I.; Kraftsik, R.

2018-01-01

Injury to peripheral nerves is often observed in the clinic and severe injuries may cause loss of motor and sensory functions. Despite extensive investigation, testing various surgical repair techniques and neurotrophic molecules, at present, a satisfactory method to ensuring successful recovery does not exist. For successful molecular therapy in nerve regeneration, it is essential to improve the intrinsic ability of neurons to survive and to increase the speed of axonal outgrowth. Also to induce Schwann cell phenotypical changes to prepare the local environment favorable for axonal regeneration and myelination. Therefore, any molecule that regulates gene expression of both neurons and Schwann cells could play a crucial role in peripheral nerve regeneration. Clinical and experimental studies have reported that thyroid hormones are essential for the normal development and function of the nervous system, so they could be candidates for nervous system regeneration. This review provides an overview of studies devoted to testing the effect of thyroid hormones on peripheral nerve regeneration. Also it emphasizes the importance of combining biodegradable tubes with local administration of triiodothyronine for future clinical therapy of human severe injured nerves. We highlight that the local and single administration of triiodothyronine within biodegradable nerve guide improves significantly the regeneration of severed peripheral nerves, and accelerates functional recovering. This technique provides a serious step towards future clinical application of triiodothyronine in human severe injured nerves. The possible regulatory mechanism by which triiodothyronine stimulates peripheral nerve regeneration is a rapid action on both axotomized neurons and Schwann cells. PMID:29722302

Necrotizing sialometaplasia of the parotid gland associated with facial nerve paralysis.

PubMed

Haen, P; Ben Slama, L; Goudot, P; Schouman, T

2017-02-01

Necrotizing sialometaplasia is a benign inflammatory lesion involving most frequently the minor salivary gland of the hard palate. Involvement of the parotid gland is rare, involvement of the parotid gland associated with facial palsy is exceptional. A 56-year-old male patient with Marfan syndrome presented with swelling and inflammation of the left parotid gland associated with progressively complete facial nerve paralysis. CT scan and MRI showed a parotid collection with hyper signal of the nearest tissues associated with erosion of the styloid process. A malignant tumor was suspected. The histological examination of a biopsy showed a lobulocentric process with necrosis, squamous metaplasia, and inflammation. The immunohistochemical examination supported a final diagnosis of necrotizing sialometaplasia. Necrotizing sialometaplasia of the parotid gland associated with facial nerve paralysis presents like a malignant neoplasm, both clinically and histologically. Only advanced immunohistochemical examination can really confirm the diagnosis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

[Electrical stimulation of the facial nerve with a prognostic function in parotid surgery].

PubMed

García-Losarcos, N; González-Hidalgo, M; Franco-Carcedo, C; Poch-Broto, J

Continuous electromyography during parotidectomies and direct stimulation of the facial nerve as an intraoperative identification technique significantly lower the rate of post-operative morbidity. To determine the usefulness of intra-operative neurophysiological parameters registered by means of electrical stimulation of the facial nerve as values capable of predicting the type of lesion and the functional prognosis. Our sample consisted of a correlative series of 20 cases of monitored parotidectomies. Post-operative facial functioning, type of lesion and its prognosis were compared with the variations in latency/amplitude of the muscle response between two stimulations of the facial nerve before and after resection, as well as in the absence or presence of muscle response to stimulation after resection. All the patients except one presented motor evoked potentials (MEP) to stimulation after resection. There was no facial damage following the operation in 55% of patients and 45% presented some kind of paresis. The 21% drop in the amplitude of the intra-operative MEP and the mean increase in latency of 13.5% correspond to axonal and demyelinating insult, respectively, with a mean recovery time of three and six months. The only case of absence of response to the post-resection stimulation presented permanent paresis. The presence of MEP following resection does not ensure that functioning of the nerve remains undamaged. Nevertheless, it can be considered a piece of data that suggests a lower degree of compromise, if it is present, and a better prognosis. The variations in latency and amplitude of the MEP tend to be intra-operative parameters that indicate the degree of compromise and functional prognosis.

Circadian Rhythm Influences the Promoting Role of Pulsed Electromagnetic Fields on Sciatic Nerve Regeneration in Rats

PubMed Central

Zhu, Shu; Ge, Jun; Liu, Zhongyang; Liu, Liang; Jing, Da; Ran, Mingzi; Wang, Meng; Huang, Liangliang; Yang, Yafeng; Huang, Jinghui; Luo, Zhuojing

2017-01-01

Circadian rhythm (CR) plays a critical role in the treatment of several diseases. However, the role of CR in the treatment of peripheral nerve defects has not been studied. It is also known that the pulsed electromagnetic fields (PEMF) can provide a beneficial microenvironment to quicken the process of nerve regeneration and to enhance the quality of reconstruction. In this study, we evaluate the impact of CR on the promoting effect of PEMF on peripheral nerve regeneration in rats. We used the self-made “collagen-chitosan” nerve conduits to bridge the 15-mm nerve gaps in Sprague-Dawley rats. Our results show that PEMF stimulation at daytime (DPEMF) has most effective outcome on nerve regeneration and rats with DPEMF treatment achieve quickly functional recovery after 12 weeks. These findings indicate that CR is an important factor that determines the promoting effect of PEMF on peripheral nerve regeneration. PEMF exposure in the daytime enhances the functional recovery of rats. Our study provides a helpful guideline for the effective use of PEMF mediations experimentally and clinically. PMID:28360885

[Using infrared thermal asymmetry analysis for objective assessment of the lesion of facial nerve function].

PubMed

Liu, Xu-long; Hong, Wen-xue; Song, Jia-lin; Wu, Zhen-ying

2012-03-01

The skin temperature distribution of a healthy human body exhibits a contralateral symmetry. Some lesions of facial nerve function are associated with an alteration of the thermal distribution of the human body. Since the dissipation of heat through the skin occurs for the most part in the form of infrared radiation, infrared thermography is the method of choice to capture the alteration of the infrared thermal distribution. This paper presents a new method of analysis of the thermal asymmetry named effective thermal area ratio, which is a product of two variables. The first variable is mean temperature difference between the specific facial region and its contralateral region. The second variable is a ratio, which is equal to the area of the abnormal region divided by the total area. Using this new method, we performed a controlled trial to assess the facial nerve function of the healthy subjects and the patients with Bell's palsy respectively. The results show: that the mean specificity and sensitivity of this method are 0.90 and 0.87 respectively, improved by 7% and 26% compared with conventional methods. Spearman correlation coefficient between effective thermal area ratio and the degree of facial nerve function is an average of 0.664. Hence, concerning the diagnosis and assessment of facial nerve function, infrared thermography is a powerful tool; while the effective ther mal area ratio is an efficient clinical indicator.

Reconstruction of Multiple Facial Nerve Branches Using Skeletal Muscle-Derived Multipotent Stem Cell Sheet-Pellet Transplantation.

PubMed

Saito, Kosuke; Tamaki, Tetsuro; Hirata, Maki; Hashimoto, Hiroyuki; Nakazato, Kenei; Nakajima, Nobuyuki; Kazuno, Akihito; Sakai, Akihiro; Iida, Masahiro; Okami, Kenji

2015-01-01

Head and neck cancer is often diagnosed at advanced stages, and surgical resection with wide margins is generally indicated, despite this treatment being associated with poor postoperative quality of life (QOL). We have previously reported on the therapeutic effects of skeletal muscle-derived multipotent stem cells (Sk-MSCs), which exert reconstitution capacity for muscle-nerve-blood vessel units. Recently, we further developed a 3D patch-transplantation system using Sk-MSC sheet-pellets. The aim of this study is the application of the 3D Sk-MSC transplantation system to the reconstitution of facial complex nerve-vascular networks after severe damage. Mouse experiments were performed for histological analysis and rats were used for functional examinations. The Sk-MSC sheet-pellets were prepared from GFP-Tg mice and SD rats, and were transplanted into the facial resection model (ST). Culture medium was transplanted as a control (NT). In the mouse experiment, facial-nerve-palsy (FNP) scoring was performed weekly during the recovery period, and immunohistochemistry was used for the evaluation of histological recovery after 8 weeks. In rats, contractility of facial muscles was measured via electrical stimulation of facial nerves root, as the marker of total functional recovery at 8 weeks after transplantation. The ST-group showed significantly higher FNP (about three fold) scores when compared to the NT-group after 2-8 weeks. Similarly, significant functional recovery of whisker movement muscles was confirmed in the ST-group at 8 weeks after transplantation. In addition, engrafted GFP+ cells formed complex branches of nerve-vascular networks, with differentiation into Schwann cells and perineurial/endoneurial cells, as well as vascular endothelial and smooth muscle cells. Thus, Sk-MSC sheet-pellet transplantation is potentially useful for functional reconstitution therapy of large defects in facial nerve-vascular networks.

Reconstruction of Multiple Facial Nerve Branches Using Skeletal Muscle-Derived Multipotent Stem Cell Sheet-Pellet Transplantation

PubMed Central

Saito, Kosuke; Tamaki, Tetsuro; Hirata, Maki; Hashimoto, Hiroyuki; Nakazato, Kenei; Nakajima, Nobuyuki; Kazuno, Akihito; Sakai, Akihiro; Iida, Masahiro; Okami, Kenji

2015-01-01

Head and neck cancer is often diagnosed at advanced stages, and surgical resection with wide margins is generally indicated, despite this treatment being associated with poor postoperative quality of life (QOL). We have previously reported on the therapeutic effects of skeletal muscle-derived multipotent stem cells (Sk-MSCs), which exert reconstitution capacity for muscle-nerve-blood vessel units. Recently, we further developed a 3D patch-transplantation system using Sk-MSC sheet-pellets. The aim of this study is the application of the 3D Sk-MSC transplantation system to the reconstitution of facial complex nerve-vascular networks after severe damage. Mouse experiments were performed for histological analysis and rats were used for functional examinations. The Sk-MSC sheet-pellets were prepared from GFP-Tg mice and SD rats, and were transplanted into the facial resection model (ST). Culture medium was transplanted as a control (NT). In the mouse experiment, facial-nerve-palsy (FNP) scoring was performed weekly during the recovery period, and immunohistochemistry was used for the evaluation of histological recovery after 8 weeks. In rats, contractility of facial muscles was measured via electrical stimulation of facial nerves root, as the marker of total functional recovery at 8 weeks after transplantation. The ST-group showed significantly higher FNP (about three fold) scores when compared to the NT-group after 2–8 weeks. Similarly, significant functional recovery of whisker movement muscles was confirmed in the ST-group at 8 weeks after transplantation. In addition, engrafted GFP+ cells formed complex branches of nerve-vascular networks, with differentiation into Schwann cells and perineurial/endoneurial cells, as well as vascular endothelial and smooth muscle cells. Thus, Sk-MSC sheet-pellet transplantation is potentially useful for functional reconstitution therapy of large defects in facial nerve-vascular networks. PMID:26372044

Inhibition of KLF7-Targeting MicroRNA 146b Promotes Sciatic Nerve Regeneration.

PubMed

Li, Wen-Yuan; Zhang, Wei-Ting; Cheng, Yong-Xia; Liu, Yan-Cui; Zhai, Feng-Guo; Sun, Ping; Li, Hui-Ting; Deng, Ling-Xiao; Zhu, Xiao-Feng; Wang, Ying

2018-06-01

A previous study has indicated that Krüppel-like factor 7 (KLF7), a transcription factor that stimulates Schwann cell (SC) proliferation and axonal regeneration after peripheral nerve injury, is a promising therapeutic transcription factor in nerve injury. We aimed to identify whether inhibition of microRNA-146b (miR-146b) affected SC proliferation, migration, and myelinated axon regeneration following sciatic nerve injury by regulating its direct target KLF7. SCs were transfected with miRNA lentivirus, miRNA inhibitor lentivirus, or KLF7 siRNA lentivirus in vitro. The expression of miR146b and KLF7, as well as SC proliferation and migration, were subsequently evaluated. In vivo, an acellular nerve allograft (ANA) followed by injection of GFP control vector or a lentiviral vector encoding an miR-146b inhibitor was used to assess the repair potential in a model of sciatic nerve gap. miR-146b directly targeted KLF7 by binding to the 3'-UTR, suppressing KLF7. Up-regulation of miR-146b and KLF7 knockdown significantly reduced the proliferation and migration of SCs, whereas silencing miR-146b resulted in increased proliferation and migration. KLF7 protein was localized in SCs in which miR-146b was expressed in vivo. Similarly, 4 weeks after the ANA, anti-miR-146b increased KLF7 and its target gene nerve growth factor cascade, promoting axonal outgrowth. Closer analysis revealed improved nerve conduction and sciatic function index score, and enhanced expression of neurofilaments, P0 (anti-peripheral myelin), and myelinated axon regeneration. Our findings provide new insight into the regulation of KLF7 by miR-146b during peripheral nerve regeneration and suggest a potential therapeutic strategy for peripheral nerve injury.

Facial-zygomatic triangle: a relationship between the extracranial portion of facial nerve and the zygomatic arch.

PubMed

Campero, A; Socolovsky, M; Martins, C; Yasuda, A; Torino, R; Rhoton, A L

2008-03-01

This study was conducted to clarify the relationships between the extracranial portion of the facial nerve (EFN) and the zygomatic arch (ZA). Four cadaveric heads (8 parotid regions), examined under 3-40x magnification, were dissected from lateral to medial to expose the EFN. In a vertical plane just anterior to the tragus, the distance from the superior edge of the ZA to the facial nerve (FN) is, on average, 26.88 mm. The FN then courses superiorly and anteriorly, crossing the ZA 18.65 mm anterior to the tragus on average. Thus, three points can be used to depict a triangle: A, at the level of the anterior border of the tragus, just above the superior edge of the ZA; B, 26 mm below A; and C, 18 mm anterior to A. This so called facial-zygomatic triangle represents the area where surgical dissection can be performed with no risk of damaging the FN. Thus, the closer one stays to the tragus, the lesser the risk of damaging the FN below the ZA. If the incision is carried out on a vertical plane closer to the tragus, the skin can be safely cut up to 2 cm below the ZA. The facial-zygomatic triangle is a very useful superficial landmark to avoid FN damage when working below the ZA.

Functional regeneration of recurrent laryngeal nerve injury during thyroid surgery using an asymmetrically porous nerve guide conduit in an animal model.

PubMed

Choi, Jeong-Seok; Oh, Se Heang; An, Hye-Young; Kim, Young-Mo; Lee, Jin Ho; Lim, Jae-Yol

2014-01-01

Vocal cord paralysis (VCP) caused by recurrent laryngeal nerve (RLN) damage during thyroidectomy commonly results in serious medico-legal problems. The purpose of this study was to evaluate the usefulness of an asymmetrically porous polycaprolactone (PCL)/Pluronic F127 nerve guide conduit (NGC) for functional regeneration in a RLN injury animal model. A biodegradable, asymmetrically porous PCL/F127 NGC with selective permeability was fabricated for use in this study. A 10-mm segment of left RLN was resected in 28 New Zealand white rabbits, and then an asymmetrically porous NGC or a nonporous silicone tube was interposed between both stumps and securely fixed. Vocal cord mobility was endoscopically evaluated at one, four, and eight weeks postoperatively. Nerve growth through NGCs was assessed by toluidine blue staining, and thyroarytenoid (TA) muscle atrophy was evaluated by hematoxylin and eosin staining. Immunohistochemical stainings for acetylcholinesterase (AchE), anti-neurofilament (NF), and anti-S100 protein were also conducted, and transmission electron microscopy (TEM) was used to evaluate functional nerve regeneration. At eight weeks postoperatively, endoscopic evaluations showed significantly better recovery from VCP in the asymmetrically porous PCL/F127 NGC group (6 of 10 rabbits) than in the silicone tube group (1 of 10 rabbits). Continued nerve growth on the damaged nerve endings was observed with time in the asymmetrically porous PCL/F127 NGC-interposed RLNs. TA muscle dimensions and AchE expressions in TA muscle were significantly greater in the asymmetrically porous PCL/F127 NGC group than in the silicone tube group. Furthermore, immunohistochemical staining revealed the expression of NF and S100 protein in the regenerated nerves in the asymmetrically porous PCL/F127 NGC group at eight weeks postoperatively, and at this time, TEM imaging showed myelinated axons in the regenerated RLNs. The study shows that asymmetrically porous PCL/F127 NGC provides

Functional Regeneration of Recurrent Laryngeal Nerve Injury During Thyroid Surgery Using an Asymmetrically Porous Nerve Guide Conduit in an Animal Model

PubMed Central

Choi, Jeong-Seok; Oh, Se Heang; An, Hye-Young; Kim, Young-Mo; Lee, Jin Ho

2014-01-01

Background: Vocal cord paralysis (VCP) caused by recurrent laryngeal nerve (RLN) damage during thyroidectomy commonly results in serious medico-legal problems. The purpose of this study was to evaluate the usefulness of an asymmetrically porous polycaprolactone (PCL)/Pluronic F127 nerve guide conduit (NGC) for functional regeneration in a RLN injury animal model. Methods: A biodegradable, asymmetrically porous PCL/F127 NGC with selective permeability was fabricated for use in this study. A 10-mm segment of left RLN was resected in 28 New Zealand white rabbits, and then an asymmetrically porous NGC or a nonporous silicone tube was interposed between both stumps and securely fixed. Vocal cord mobility was endoscopically evaluated at one, four, and eight weeks postoperatively. Nerve growth through NGCs was assessed by toluidine blue staining, and thyroarytenoid (TA) muscle atrophy was evaluated by hematoxylin and eosin staining. Immunohistochemical stainings for acetylcholinesterase (AchE), anti-neurofilament (NF), and anti-S100 protein were also conducted, and transmission electron microscopy (TEM) was used to evaluate functional nerve regeneration. Results: At eight weeks postoperatively, endoscopic evaluations showed significantly better recovery from VCP in the asymmetrically porous PCL/F127 NGC group (6 of 10 rabbits) than in the silicone tube group (1 of 10 rabbits). Continued nerve growth on the damaged nerve endings was observed with time in the asymmetrically porous PCL/F127 NGC-interposed RLNs. TA muscle dimensions and AchE expressions in TA muscle were significantly greater in the asymmetrically porous PCL/F127 NGC group than in the silicone tube group. Furthermore, immunohistochemical staining revealed the expression of NF and S100 protein in the regenerated nerves in the asymmetrically porous PCL/F127 NGC group at eight weeks postoperatively, and at this time, TEM imaging showed myelinated axons in the regenerated RLNs. Conclusion: The study shows that