Nerve Anastomosis Research Articles

Efficacy of Silicone Conduit in the Rat Sciatic Nerve Repair Model: Journey of a Thousand Miles.

A lot of options have been tried for bridging the two ends of the injured nerves. Researchers have used decellularized nerve grafts, artificial materials and even nerve growth factors to augment functional recovery. These materials are either costly or inaccessible in developing world. The study aimed to evaluate the efficacy of the silicone conduit in a rat sciatic nerve injury model. 24 healthy Sprague-Dawley (SD) rats (250-300 grams; 8-10 weeks) were used and right sciatic nerve was exposed; transected and re-anastomosed by two different methods in 16 rats. In control group, n = 8 (Group I) the sciatic nerve was untouched; Group II (reverse nerve anastomosis, n = 8): 1-centimeter of nerve was cut and re-anastomosed by using 10-0 monofilament suture; Group III (silicone conduit, n = 8) 1-centimeter nerve segment was cut, replaced by silicone conduit and supplemented by fibrin glue]. Evaluation of nerve recovery was done functionally (pain threshold and sciatic functional index) over 3 months and histologically and electron microscopically. Functional results showed a trend of clinical improvement in Group III and II but recovery was poor and never reached up to normal. Histopathological and electron microscopic results showed an incomplete axonal regeneration in Groups II and III. Psychological analyses showed that no outwards signs of stress were present and none of the rats showed paw biting and teeth chattering. The silicone conduit graft may be an economical and effective alternative to presently available interposition grafts, however for short segments only.

Surgical Technique of Xu's CC7 Procedure "Contralateral C7 to C7 Cross Nerve Transfer Through a Trans Longus Colli, Prespinal Route for Treating Spastic Arm".

The contralateral C7 transfer has been used for the treatment of brachial plexus root avulsion since 1986, and several modifications of this surgery have been described. Previous trial has verified the safety and effectiveness of the contralateral C7 to C7 cross nerve transfer for patients with longstanding spastic paralysis due to cerebral injuries, including stroke, traumatic brain injury, or cerebral palsy. However, the procedures for the surgery were not introduced in detail, with only rough descriptions. To introduce and promote the Xu's CC7 procedure (contralateral C7 to C7 cross nerve transfer through a trans longus colli, prespinal route). The renewed procedures were elaborated step by step, and the tips and tricks were clarified by case illustration in detail. Briefly, a modified trans longus colli, prespinal route was created, allowing the displaced C7 nerve to pass through the channel safely at the shortest distance. Tension-free anastomosis of the bilateral C7 nerves was achieved via the Xu's CC7 procedure with less surgical trauma while reducing the surgery time, postoperative recovery time, and nerve regeneration time. The Xu's CC7 procedure is a safer and more efficient technique for contralateral C7 to C7 cross nerve transfer. The detailed description in this article provides meaningful information for surgeons interested in the procedure.

Erratum to: "Masseter-to-Facial Cranial Nerve Anastomosis: A Report of 30 Cases" by Zotov et al. Operative Neurosurgery, opaa140, https://doi.org/10.1093/ons/opaa140.

Erratum to: "Masseter-to-Facial Cranial Nerve Anastomosis: A Report of 30 Cases" by Zotov et al. Operative Neurosurgery, opaa140, https://doi.org/10.1093/ons/opaa140.

Microsurgical Anastomosis of Median and Ulnar Nerve by Sural Nerve Grafting

The young to the middle-aged group is most affected in peripheral nerve injuries (PNI) and male gender shows predominance among the patients. Upper extremities are most likely to get injured which is three-fourth of total patients. This case report is about repairing of median and ulnar nerve by autologous sural nerve grafting. A 28-year-old man had an alleged history of a stab wound at his right arm 3 months ago. He had clinical features of complete injury of his right ulnar and median nerve. Nerve electrophysiology and magnetic resonance imaging also supported the diagnosis. Neuromas were formed in both the upper ends and the gap between the ends was more than 2 centimetres. The nerve was repaired under an operating microscope by sural nerve and musculocutaneous nerve grafting with very thin monofilament suture. His postoperative recovery was uneventful. Sensory recovery was earlier than motor recovery.

En bloc resection of locally perforated colonic malignancy with removal of iliopsoas and femoral nerve and primary anastomosis

En bloc resection of locally perforated colonic malignancy with removal of iliopsoas and femoral nerve and primary anastomosis

Green Tea Polyphenols Promote Functional Recovery from Peripheral Nerve Injury in Rats.

BackgroundPeripheral nerve injury (PNI) is a common and progressive disorder with sensory and motor deficits in the peripheral nervous system (PNS). Treatment is difficult, with unfavorable prognosis. Green tea polyphenols (GTPs) exert neuroprotective effects on regeneration of the central nervous system (CNS). However, the effects of GTPs on functional recovery of the PNS have not been fully characterized. Consequently, the present study investigated the effects of GTPs on nerve regeneration of rats with PNI.Material/MethodsThe model of PNI was established in rats by sciatic nerve injury (SNI). Adult male Wistar rats with SNI were randomly divided into a vehicle group and a GTPs group. The compound muscle action potential (CMAP) of rat sciatic nerves (SN) was measured using the CM6240 physiological signal acquisition and processing system. The wet weight of the triceps muscle was determined using an analytical balance. The number of myelinated nerve fibers was counted under an optical microscope. Ultrastructure of the regenerated nerves in SN was observed by transmission electron microscopy. The mRNA and protein expression of nerve growth factor (NGF), growth-associated protein-43 (GAP-43), neurofilament 200 (NF200), and myelin-associated glycoprotein (MAG) in SN stumps were measured by real-time quantification PCR (RT-qPCR) and Western blot, respectively.ResultsIn rats with SNI, GTPs relieved the adhesion between nerve anastomosis and surrounding tissues, and significantly increased nerve conduction velocity, wet weight of the triceps muscle, and development and axonal regeneration of myelinated nerve fibers. Moreover, GTPs promoted the mRNA and protein expressions of NGF, GAP-43, NF200, and MAG in SN stumps.ConclusionsGTPs promotes nerve regeneration in rats with SNI.

Clinical outcomes of lingual nerve repair

Lingual nerve injury, a well-described complication of third molar removal, may result in permanent lingual sensory deficit leading to symptoms including lost or altered sensation, inadvertent tongue biting, and the development of unpleasant neuropathic pain, with consequent impaired quality of life. We analysed outcomes of a prospective case series to determine whether direct anastomosis of the lingual nerve results in improved sensory recovery and reduced neuropathic pain, and whether delayed surgery is worthwhile. In 114 patients who underwent nerve repair at our nerve injury clinic following damage sustained during mandibular third molar removal, sensory deficit was assessed before and after surgery using a questionnaire and visual analogue scales (VAS) to assess pain, tingling, and discomfort. Neurosensory tests were utilised to evaluate light touch, pin-prick, and two-point discrimination thresholds. Subjectively, 94% patients felt their sensation had improved following nerve repair, with significant reductions in the incidence of tongue biting (p<0.0001), impaired speech (p<0.0001), and neuropathic pain (p=0.0017). Quantitative neurosensory data showed highly significant improvements in light touch, pin-prick, and two-point discrimination (all p<0.0001), and VAS scores for pain (p=0.0145), tingling (p<0.0025), and discomfort (p<0.0001) were significantly reduced. Patients with high levels of pain preoperatively (VAS>40) showed highly significant reductions in pain (p<0.0001). No correlation was found between surgical outcome and patient’s age or delay until surgery. Lingual nerve repair results in good sensory outcomes and significant improvements in the incidence and degree of neuropathic pain, even when delayed.

Cranial and spinal nerve anastomoses in man

Nerve anastomoses normally exist in human body between cranial nerves spinal nerves and between cranial and spinal nerves They are also frequently performed in surgeries for recovery of functions of denervated areas These anastomoses are of utmost importance in the process of reinnervation and nerve repair following individual nerve injury Examples of cranial nerve anastomoses are demonstrated between the branches of the facial nerve and other nerves the nerves of the tongue the laryngeal nerves of the vagus nerve and the optic nerves Examples of spinal nerve anastomoses are also displayed between the spinal nerve roots and between the individual nerves of the different somatic nerve plexuses cervical brachial lumbar and sacral

Grading system and surgical approaches for endolymphatic sac tumors.

Endolymphatic sac tumors (ELSTs) are rare, low-grade adenocarcinomas arising from the endolymphatic sac. This study aims to present a novel grading system for ELSTs to determine the optimal management strategy. We performed a retrospective analysis of 16 patients with 17 ELSTs. The tumor location and involved adjacent neurovascular structures on CT and MRI were selected to establish the grading system. Based on the novel grading system, grade III a tumors were most common (7/17), followed by grade I (4/17), grade II (3/17), and grade III b (3/17) tumors. Eight advanced ELSTs (grade III a and III b) received an infra-temporal fossa approach, while the other 6 early stage ELSTs (grade I and II) underwent either a retrolabyrinthine approach with posterior petrosectomy or a translabyrinthine approach combined with subtotal temporal bone resection. Hearing preservation was achieved in 2 grade I patients. Postoperative facial nerve function was HB II in 1 grade III a patient who underwent anterior facial nerve transposition and was HB III in 4 advanced patients who received facial nerve grafts with the great auricular nerve or facial-hypoglossal nerve anastomosis. The mean follow-up time was 35.1months. Two grade III patients and 1 grade II patient had tumor recurrence during follow-up, among whom 1 grade III b patient had two cases of recurrence. A correct initial diagnosis was established in all patients after meticulous imaging studies. Surgical resection is still the first choice to manage patients with ELSTs. The novel grading system enables surgeons to select tailored surgical approaches. Long-term follow-up is necessary following surgical intervention.

Electromyography as an intraoperative test to assess the quality of nerve anastomosis – experimental study on rats

BackgroundMany factors contribute to successful nerve reconstruction. The correct technique of anastomosis is one of the key elements that determine the final result of a surgery. The aim of this study is to examine how useful an electromyography (EMG) can be as an objective intraoperative anastomosis assessment method.MethodsThe study material included 12 rats. Before the surgery, the function of the sciatic nerve was tested using hind paw prints. Then, both nerves were cut. The left nerve was sutured side-to-side, and the right nerve was sutured end-to-end. Intraoperative electromyography was performed. After 4 weeks, the rats were reassessed using the hind paw print analysis and electromyography.ResultsAn analysis of left and right hind paw prints did not reveal any significant differences between the length of the steps, the spread of the digits in the paws, or the deviation of a paw. The width of the steps also did not change.Electromyography revealed that immediately after a nerve anastomosis (as well as 4 weeks after the surgery), better nerve conduction was observed through an end-to-end anastomosis. Four weeks after the surgery, better nerve conduction was seen distally to the end-to-end anastomosis.ConclusionsThe results indicate that in acute nerve injuries intraoperative electromyography may be useful to obtain unbiased information on whether the nerve anastomosis has been performed correctly – for example, in limb replantation.When assessing a nerve during a procedure, EMG should be first performed distally to the anastomosis (the part of the nerve leading to muscle fibers) and then proximally to the anastomosis (the proximal part of the nerve). Similar EMG results can be interpreted as a correct nerve anastomosis.The function of the distal part of the nerve and the muscle remains intact if the neuromuscular transmission is sustained.

Ansa-to-Recurrent Laryngeal Nerve Anastomosis Aided by Vagal Nerve Evoked Electromyography: Surgical Technique

Introduction: Ansa-to-recurrent laryngeal nerve (ANSA-RLN) anastomosis procedures in children with unilateral vocal fold immobility (UVFI) are considered a first-line treatment strategy for long-st...

Assessment of axonal sprouting and motor performance after hypoglossal-facial end-to-side nerve repair: experimental study in rats.

Hypoglossal-facial nerve anastomosis (HFA) aims to reanimate denervated mimic muscles with hypoglossal axons when the transected facial nerve is not accessible. The aim of this study was to evaluate the recovery of HFA using a "Y" tube in two variants: (1) the proximal stump of the hypoglossal nerve was entubulated to the "Y" tube (classic "Y" tube HFA) and (2) the "Y" tube was sutured to an epineurial window of a slightly damaged hypoglossal nerve (end-to-side "Y" tube HFA). A total of 48 adult female rats were divided into four groups: intact controls (group 1), sham operated (group 2), classic "Y" tube HFA (group 3) and end-to-side "Y" tube HFA (group 4). The abdominal aorta with both common iliac arteries of isogeneic male rats served as the Y-tube conduit. Animals from group 4 recovered better than those from group 3: the degree of collateral axonal branching (3 ± 1%) was significantly lower than that determined in group 3 (13 ± 1%). The mean deviation of the tongue from the midline was significantly smaller in group 4 (6 ± 4°) than that measured in animals from group 3 (41 ± 6°). In the determination of vibrissal motor function in group 3 and group 4, a decrease in amplitude was found to be - 66% and - 92%, respectively. No differences in the reinnervation pattern of the target muscles were detected. As a result, these surgical models were not determined to be able to improve vibrissal movements. It was concluded that performance of end-to-side "Y" tube HFA diminishes collateral axonal branching at the lesion site, which in turn, promotes better recovery of tongue- and vibrissal-motor performance.

Selective vagus-recurrent laryngeal nerve anastomosis in thyroidectomy with cancer invasion or iatrogenic transection.

Immediate recurrent laryngeal nerve (RLN) reconstruction at the time of thyroid cancer extirpation can provide excellent postoperative phonatory function. This study is to present our experience with the methods of RLN reconstruction, and to evaluate the role of selective vagus to RLN anastomosis (SVR) in thyroidectomy. Respective review of RLN reconstruction in thyroid surgery from January 2004 to October 2018 was conducted in two tertiary referral academic medical centers. Immediate RLN reconstruction was performed for primary thyroidectomy patients with intraoperative nerve tumor invasion or iatrogenic transection. Laryngofiberoscopic examination, voice evaluation of maximum phonation time, and GRBAS scale were performed preoperatively, on the second day after surgery, and monthly postoperatively for the first year. A total of 37 patients were enrolled. Twenty-nine RLNs were resected caused by tumor-associated trauma; the other nerves were inadvertently transected. Direct anastomosis (DA) was performed in eight patients, free nerve graft (FNG) was performed in four patients, ansa cervicalis to RLN anastomosis (ARA) was performed in eight patients, and SVR was performed in 17 patients. The mean periods from the reinnervation surgery of DA, SVR, ARA, and FNG to the phonation recovery were 46 ± 19 (days), 41 ± 29 (days), 83 ± 21 (days), and 137 ± 32 (days), respectively. There were improvements in the GRBAS scale of perceptual voice quality at 1 month for DA and SVR, 2months for ARA. Intraoperative SVR reinnervation demonstrated voice improvement postoperatively and might be an effective treatment for thyroidectomy-related permanent unilateral vocal cord paralysis.

Results of End-To-Side Hypoglossal-Facial Nerve Anastomosis in Facial Paralysis after Skull Base Surgery.

Introduction:The primary aim of facial reanimation surgery is to restore tone, symmetry, and movement to the paralyzed face. Hypoglossal-facial end-to-side anastomosis provides satisfactory facial reanimation in the irreversible proximal injury of the facial nerve. This study discussed the facial function results of end-to-side anastomosing of hypoglossal nerve to facial nerve when the injury occurred during skull base surgery.Materials and Methods:The present study enrolled a total of 10 patients who underwent end-to-side hypoglossal-facial nerve anastomosis after facial nerve paralysis due to skull base surgery. The data of the patients were gathered from hospital records, pictures, and movies during the 18 months of follow-up. Results:At the 18 months of follow-up, seven (70%) and three (30%) patients were reported with grades III and IV of the House-Brackmann scoring system, respectively. In total, out of the seven grade III patients, six subjects underwent early anastomosis (within the first year of the paralysis). On the other hand, among patients with grade IV, two subjects had late anastomosis.Conclusion:It seems that early end-to-side hypoglossal-facial anastomosis can be a favorable surgical option with good facial function results for reanimating the facial function of patients with facial paralysis following skull base surgery.

Long-term electrophysiological assessment after hypoglossal-facial anastomosis.

To investigate and provide objective documentation of the possible differences in the axonal reinnervation process of facial muscles after hypoglossal-facial nerve anastomosis. Then, to search for the presence of the trigemino-hypoglossal reflex and determine whether it indicates better peripheral recovery. Electrophysiological examination performed on 20 patients who had undergone VII-XII anastomosis, with follow-up periods of more than 2years. The mean follow-up time after surgery was 4.1 ± 1.3years (range 2-8years). The degrees of axonal reinnervation for the orbicularis oculi (OOc) and orbicularis oris (OOr) were 46.91 ± 19.77 and 32.65 ± 14.85, respectively. And the difference between these muscles was statistically significant (p = 0.018) in favor of the OOc. In addition, R1 blink reflexes that were not followed by R2 components were observed in 30% of the patients. However, these 6 patients with short-latency potential did not differ from the others in terms of latency, the amplitude of compound muscle action potential (CMAP), and degree of axonal reinnervation (p > 0.05) at both muscles (OOc and OOr). The recoveries of the lower face and upper face are different after VII-XII anastomosis, and in our patients the OOc healed better. In addition, R1 blink reflexes that were not followed by R2 components were observed in 30% of the patients. However, the patients with these blink reflexes did not have better peripheral healing in their neuromuscular units, which suggests that the blink reflex is not an indicator for peripheral recovery.

Supermicrosurgery for oncologic reconstructions.

With advancement of microsurgical techniques, supermicrosurgery has been developed. Supermicrosurgery allows manipulation (dissection and anastomosis) of vessels and nerves with an external diameter of 0.5 mm or smaller. Because quality of life of cancer survivors is becoming a major issue, less invasive and functionally-better oncological reconstruction using supermicrosurgical techniques attracts attention. Conventional free flap reconstruction usually sacrifices major vessels and muscle functions, whereas supermicrosurgical free flaps can be transferred from anywhere using innominate vessels without sacrifice of major vessel/muscle. Since a 0.1-0.5 mm vessel can be anastomosed, patient-oriented least invasive reconstruction can be accomplished with supermicrosurgery. Another important technique is lymphatic anastomosis. Only with supermicrosurgery, lymph vessels can be securely anastomosed, because lymph vessel diameter is usually smaller than 0.5 mm. With clinical application of lymphatic supermicrosurgery, various least invasive lymphatic reconstruction has become possible. Lymphatic reconstruction plays an important role in prevention and treatment of lymphatic diseases following oncologic surgery such as lymphedema, lymphorrhea, and lymphocyst. With supermicrosurgery, various tissues such as skin/fat, fascia, bone, tendon, ligament, muscle, and nerves can be used in combination to reconstruct complicated defects; including 3-dimensional inset with multi-component tissue transfer.

Repair of medial plantar wound with posterior tibial artery perforator combined with saphenous nerve nutrient vessel fascial flap

Objective To investigate the surgical technique and its clinical efficacy of the flaps with double blood supply through posterior tibial artery perforators and saphenous nerve nutrient vessels for the secondary stage repair of medial plantar defects. Methods Thirteen patients with medial plantar tissue defects, who were repaired by posterior tibial artery perforator flaps combined with saphenous nerve nutrient vascular fascia flaps from January, 2016 to December, 2018, were studied. The patients were 9 males and 4 females, aged 23-69 (mean age 36.9) years. All defects were near the tarsometatarsal joints in the medial planta, and the soft tissue defects were 4.5 cm× 5.0 cm-8.0 cm×14.0 cm in size. The donor sites were directly sutured or repaired with free graft of ipsilateral thigh full-thickness skin. All patients in this study were followed-up for 6-12 months to observe the function of affected limbs and the recovery of flap donor and recipient sites through outpatient visits and telephone reviews. Results All the 13 flaps survived successfully. One flap developed a small area of necrosis at the distal end, which was healed after partial stitch removal, decompression and dressing change. Another flap had shown purple bruises and tension blisters, surgical exploration was then performed to remove local hematoma and the flap survived after pedicle stitch removal and decompression. One flap received flap thinning and shaping at 8 months after surgery. All flaps showed normal in color, temperature, capillary reaction, soft in texture and without swollen appearance. The affected feet were not apparently restricted when walking, and the functions had satisfactory recovery. Conclusion Posterior tibial artery perforator flap carrying saphenous nerve and great saphenous vein is able to achieve higher and reliable flap survival and better blood supply. Anastomosis of the saphenous nerve carried by flap with cutaneous nerve of the recipient site helps to reconstruct the protective sensation of the flap, which is an effective approach in clinically repairing of the medial plantar defects. Key words: Posterior tibial artery perforator flap; Saphenous nerve nutrient vascular fascial flap; Medial plantar; Soft tissue defect; Repair

Immediate Ansa Cervicalis-to-Recurrent Laryngeal Nerve Anastomosis for the Management of Recurrent Laryngeal Nerve Infiltration by a Differentiated Thyroid Carcinoma

Objectives: The optimal surgical approach to treat recurrent laryngeal nerve (RLN) infiltration by differentiated thyroid cancer (DTC) remains a subject of debate. This study explored the feasibility and efficiency of immediate ansa cervicalis nerve (ACN)-to-RLN anastomosis for the management of RLN infiltration by DTC. Material and Methods: Fifty-three patients who underwent immediate ACN-to-RLN anastomosis during DTC extirpation were enrolled in the present study. Thirty-seven cases presented with unilateral vocal cord paralysis before the operation (Group A), and another 16 patients presented with normal vocal cord mobility preoperatively (Group B). Multidimensional assessments, videostroboscopy, voice assessment, and laryngeal electromyography (LEMG) were performed preoperatively and postoperatively. Results: All videostroboscopy, voice assessment and LEMG parameters in Group A deteriorated 1 month after the operation and improved 1 year after the operation compared with preoperative data. In Group B, all parameters 1 year after the operation improved significantly compared with the corresponding parameters 1 month after the operation. LEMG in Group A and B provided substantial evidence for the maturation of neural regeneration from ACN and demonstrated that the laryngeal muscles were reinnervated successfully by this procedure. Conclusions: If the RLN is infiltrated by DTC, immediate ACN-to-RLN anastomosis during complete excision of DTC could restore satisfactory phonatory function and does not compromise oncological radicality.

Evaluation of VIIth-XIIth cranial nerve anastomosis results by age.

To evaluate VIIth-XIIth cranial nerve (hypoglossal-facial nerve) anastomosis results by age. A total of 34 patients who attended a follow-up visit in 2016, aged 20-63 years, were enrolled. The House-Brackmann facial nerve function grading system and the Facial Clinimetric Evaluation scale were applied. Regarding post-anastomosis facial nerve function, in the group aged 40 years or less, 14 patients (78 per cent) had House-Brackmann grade III and 4 patients (22 per cent) had House-Brackmann grade IV facial nerve function post-anastomosis. In the group aged over 40 years, nine patients (56 per cent) had House-Brackmann grade III and seven patients (44 per cent) had House-Brackmann grade IV facial nerve function post-anastomosis. There was a statistically significant difference between the two groups in mean facial movement domain scores (p = 0.02). Analysis between age and facial movement score in all 34 patients demonstrated a moderate negative correlation (Pearson correlation coefficient: -0.38) and statistical significance (p = 0.02). Facial reanimation yielded better results in younger than in older patients.

Functional Evaluation of Sciatic Nerve Anastomosis Wraped by Freeze Dried Human Amniotic Membrane in Sprague Dawley Rat

Background. Peripheral nerve injury (PNI) is a common medical condition. The defected nerve, if not repaired as early as possible, can cause long-term denervation and neurotrophy failure for the target organ. This leads to a series of denervation manifestations, such as muscle atrophy, loss of sensory function, etc. and ultimately, these manifestations seriously affect the patient’s sensorimotor function.1,2 Amniotic membranes have been widely used in ophthalmology and skin injury repair because of their anti-inflammatory properties. In this study, we measured therapeutic efficacy and determined if amniotic membranes could be used for sciatic nerve repair.Material and methods. A post test only control group design has been done in 10 healthy Sprague Dawley rats. In all rats, a unilateral right side sciatic nerve transection was performed and reanastomosed by different methods: Group I (control group): included 5 rats, the anastomosis was done by epineural microsutures using 8/0 nylon. Group II: included 5 rats, the anastomosis was done by epineural microsutures using 8/0 nylon and then wraped by freeze dried human amniotic membrane. Functional evaluation of nerve recovery was done over 3 weeks postoperatively using walking tract analysis and calculate using Sciatic Functional Index.Result. Functional results showed that there was no significant difference of the sciatic functional index (SFI) between group I and group II.Conclusion. We can conclude that during 3 weeks functional evaluation, there is no significant difference between control group and experimental group that achieved freeze dried human amniotic membrane.Keywords: sciatic nerve injury, freeze dried human amniotic membrane, walking tract analysis, sciatic functional index.