OBJECTIVETo study the repairing method of facial nerve defect using nerve elongation, and the biomechanical properties of peripheral nerves. METHODS A novel device for peripheral nerve elongation was designed and manufactured. With the device, facial nerves of rabbits were expanded acutely and chronically by string-type loading. The facial nerves were studied with histological and electrophysiological examinations before and after elongation. RESULTS There were no considerable necrosis, degeneration, and infection in the facial nerves after elongation. The experimental animals took food normally and their body temperature were stable. Histological examinations showed dispersing Sunderland degree III injury and occasionally broken capillary blood vessels in the acute group, thicker nerve and fibroblasts hyperplasia between nerve bundles in the chronic group. The electromyogram(EMG) of buccal muscle and nerve conductive velocity(NCV) showed the maximal range was (18.7 +/- 2.4)% in the acute group, and (30.8 +/- 2.4)% in the chronic group. CONCLUSION It suggests that the novel nerve elongation method is feasible, and it can be used to study the nerve elongation basically and clinically.
Objective To study the microsurgical anatomy of the facial nerve (FN ) trunk and provide some important morphometric data about facialhypoglossal nerve anastomosis (FHA). Methods Bilateral microsurgical dissection was performed on the heads of 9 cadarers fixed with formalinwith three different methods. In the first method, the posterior belly of the digastric muscle was used as a mark, and the FN trunk was identified on the medial side ofthis muscle. In the second method, dissection was initiated at the parotid gland, the FN trunk was identified at its entrance into the parotid gland. In the third method, the styloid process was identified and traced back to the stylomastoid foramen (SMF). The FN trunk was identified on its emergence from the SMF. In every dissection, the whole FN trunk was exposed; its diameter and depth at the the SMF and its length were measured; its relationship, with other structures was studied. Results The FN invariably emerged from the cranial base through the SMF. Its diameter upon its emergence from the foramen was 2.57±0.60mm. The mean minimal distance of the FN trunk from the skin surface in this area was 22.62±2.88 mm. The length of the FN trunk was 15.71±1.97 mm. The distance between the bifurcation and the mastoidale was 18.20±4.41 mm. The distance between the bifurcation and the mandibular angle was 39.91±8.38 mm. The distance between the mastoidale and the SMF was 17.91±2.68 mm. The branches fromthe FN trunk proximal to its bifurcation were the posterior auricular nerve, the digastric muscle nerve and the stylohyoid muscle nerve.Conclusion The third method to expose the FN trunk on its emergence from the SMFis safe and reliable. It is feasible to use only part of the hypoglossal nerve fibers for anastomosis with the FN trunk.
ObjectiveTo investigate the early effects of acellular xenogeneic nerve combined with adipose-derived stem cells (ADSCs) and platelet rich plasma (PRP) in repairing facial nerve injury in rabbits.MethodsThe bilateral sciatic nerves of 15 3-month-old male Sprague-Dawley rats were harvested and decellularized as xenografts. The allogeneic ADSCs were extracted from the neck and back fat pad of healthy adult New Zealand rabbits with a method of digestion by collagenase type Ⅰ and the autologous PRP was prepared by two step centrifugation. The 3rd generation ADSCs with good growth were labelled with CM-Dil living cell stain, and the labelling and fluorescence attenuation of the cells were observed by fluorescence microscope. Another 32 New Zealand rabbits were randomly divided into 4 groups and established the left facial nerve defect in length of 1 cm (n=8). The nerve defects of groups A, B, C, and D were repaired with CM-Dil-ADSCs composite xenogeneic nerve+autologous PRP, CM-Dil-ADSCs composite xenogeneic nerve, xenogeneic nerve, and autologous nerve, respectively. At 1 and 8 weeks after operation, the angle between the upper lip and the median line of the face (angle θ) was measured. At 4 and 8 weeks after operation, the nerve conduction velocity was recorded by electrophysiological examination. At 8 weeks after operation, the CM-Dil-ADSCs at the distal and proximal ends of regenerative nerve graft segment in groups A and B were observed by fluorescence microscopy; after toluidine blue staining, the number of myelinated nerve fibers in regenerated nerve was calculated; the structure of regenerated nerve fibers was observed by transmission electron microscope.ResultsADSCs labelled by CM-Dil showed that the labelling rate of cells was more than 90% under fluorescence microscope, and the labelled cells proliferated well, and the fluorescence attenuated slightly after passage. All the animals survived after operation, the incision healed well and no infection occurred. At 1 week after operation, all the animals in each group had different degrees of dysfunction. The angle θ of the left side in groups A, B, C, and D were (53.4±2.5), (54.0±2.6), (53.7±2.4), and (53.0±2.1)°, respectively; showing significant differences when compared with the healthy sides (P<0.05). At 8 weeks after operation, the angle θ of the left side in groups A, B, C, and D were (61.9±4.7), (56.8±4.2), (54.6±3.8), and (63.8±5.8)°, respectively; showing significant differences when compared with the healthy sides and with the values at 1 week (P<0.05). Gross observation showed that the integrity and continuity of regenerated nerve in 4 groups were good, and no neuroma and obvious enlargement was found. At 4 and 8 weeks after operation, the electrophysiological examination results showed that the nerve conduction velocity was significantly faster in groups A and D than in groups B and C (P<0.05), and in group B than in group C (P<0.05); no significant difference was found between groups A and D (P>0.05). At 8 weeks after operation, the fluorescence microscopy observation showed a large number of CM-Dil-ADSCs passing through the distal and proximal transplants in group A, and relatively few cells passing in group B. Toluidine blue staining showed that the density of myelinated nerve fibers in groups A and D were significantly higher than those in groups B and C (P<0.05), and in group B than in group C (P<0.05); no significant difference was found between groups A and D (P>0.05). Transmission electron microscope observation showed that the myelinated nerve sheath in group D was large in diameter and thickness in wall. The morphology of myelin sheath in group A was irregular and smaller than that in group D, and there was no significant difference between groups B and C.ConclusionADSCs can survive as a seed cell in vivo, and can be differentiated into Schwann-like cells under PRP induction. It can achieve better results when combined with acellular xenogeneic nerve to repair peripheral nerve injury in rabbits.
Using transplantation of free muscle with microneurovascular anastomosis for 46 cases of late facial paralysis, we selected M. latissimus dorsi as neurovascularized muscle bundle graft in 28 of them. This was not only an operation for facial dynamic reconstruction but also a new method for reinnervation of oral and ocular sphincter. After operation all of them revealed symmetry with voluntary motions. The results were satisfactory. The indications for surgical treatment, the procedure, and the management after the treatment were discussed in details. The importance of reeducation of the regenerating nerve and the necessity of twostaged operation were also discussed.
ObjectivesTo assess the efficacy and safety of corticosteroid and antiviral agents for idiopathic facial nerve paralysis (IFNP) by network meta-analysis.MethodsPubMed, EMbase, The Cochrane Library, CBM, CNKI, WangFang Data and VIP databases were electronically searched to collect randomized controlled trials (RCTs) of corticosteroid and antiviral agents for IFNP from inception to January 31th, 2018. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. The meta-analysis was performed by R 3.3.3 and Stata 13.0 software.ResultsA total of 16 RCTs involving 3 061 patients were included. The results of network meta-analysis showed that: for the facial function recovery rates, corticosteroid plus antiviral agents was superior to placebo and antiviral agents alone at 3-month follow-up. Corticosteroid plus antiviral agents was superior to placebo, antiviral agents or corticosteroid alone at 6-month follow-up (if the satisfactory recovery was defined as a House-Brackmann grade class Ⅱ or below). When the follow-up exceeded 6 months, corticosteroid alone was superior to placebo and antiviral agents alone, corticosteroid plus antiviral agents was superior to placebo and antiviral agents alone. All of the differences above were statistically significant. For the sequelae, corticosteroid plus antiviral agents and corticosteroid alone were superior to placebo and antiviral agents alone. Corticosteroid plus antiviral agents was superior to corticosteroid alone. The differences were statistically significant. For the adverse events, there were no significant differences between any other pairwise comparisons of these different interventions.ConclusionConsidering the efficacy and safety, patients with IFNP treated corticosteroid plus antiviral agents are more likely to have a better recovery of facial function and less likely to develop sequelae, followed by corticosteroid alone. More high-quality, large scaled and multicenter RCTs are required to verify the conclusions above, and focus on the treatment of children and patients with severe facial paralysis.
ObjectiveTo study the anatomicopathological relation between facial nerve (FN) and acoustic neuronoma (AN) and summarize the techniques of how to protect facial nerves in microsurgery. MethodsA retrospective analysis of 585 patients with acoustic neuronmas treated by microsurgery for the first time between January 2007 and March 2012 was carried out. Anatomicopathological relation between FN and AN and protection of the facial nerve were described. ResultsThe tumors were totally removed microsurgically in 552 patients, and the total removal rate was 94.4%. Subtotal removal was performed in 33 patients. Facial nerve was anatomically preserved in 558 cases, and the rate of facial nerve preservation was 95.4%. After one-year follow-up, 549 patients had House-Brackmann Ⅰ-Ⅳ function. The location and shape of the FN along the tumor was identified as the follows: FN displaced along the ventral and superior surface of the tumor in 279 patients (47.7%), the ventral and central in 243 (41.5%), the ventral and inferior in 33 (5.6%), the dorsal in 10, the superior pole in 6, the inferior pole in 3, and FN surrounded in 11. ConclusionGood understanding of the meaning of anatomicopathological relation between FN and AN, intraoperative monitoring and perfect microneurosurgical skills are important in achieving the goal of total resection of acoustic neuromas and anatomic reservation of the facial nerve.
ObjectiveTo analyse the microsurgical treatment and facial nerve preservation of giant acoustic neuromas. MethodsUnder the conditions of facial nerve monitoring, 400 patients with giant acoustic neuromas underwent microsurgical removal via suboccipital retrosigmoid approach between January 2005 and January 2013. There were 186 males and 214 females, with the age ranged from 15 to 74 years (mean, 41.6 years). The disease duration was 2-13 years (mean, 2.4 years). The lesions were located at the left cerebellopontine angle region (CPA) in 191 cases, right CPA in 200 cases, bilateral CPA in 9 cases. The clinical manifestations included unilateral hearing loss and tinnitus as first symptoms in 389 cases, facial numbness in 373 cases, unilateral facial paralysis in 370 cases, headache in 269 cases, lower cranial nerve symptoms with drinking cough and dysphagia in 317 cases, and unstable gait in 342 cases. Preoperative skull base thin layer CT showed varying degrees of horn-like expansion in ipsilateral internal auditory canal opening. MRI showed cysts in 78 cases and solid masses in 322 cases; with hydrocephalus in 269 cases. Postoperative cranial MRI or CT was taken to observe the extent of tumor resection. The preservation of facial nerves in anatomy was assessed by intraoperative microscope video and electrophysiological monitoring; the facial nerves function was assessed according to House-Brackmann (HB) classification on the first day after operation; and the rehabilitation of facial nerve function was also assessed at discharge and at 1 year postoperatively by using HB grade. ResultsTotal tumor removal was achieved in 372 cases (93.00%), and subtotal removal in 28 cases (7.00%). One case died of delayed brainstem ischemia at 14 days after operation, and 1 case died of lung infection at 20 days after operation; 398 cases were followed up 6 months to 8 years (mean, 3.5 years). Recurrence occurred in 1 case because of neurofibromatosis at 5 years after operation. The rate of anatomical preservation of the facial nerve during operation was 91.75% (367/400), and the functional preservation rate at the first day after operation was 62.75% (251/400). The HB grade of facial nerve function showed significant difference aomng 3 time points (at the first day, at discharge and at 1 year after operation) (χ2=23.432, P=0.000). Complications included postoperative intracranial infection in 11 cases (2.75%), cerebrospinal fluid leakage in 29 cases (7.25%), aggravated lower cranial nerve symptoms in 18 cases (4.50%), subcutaneous effusion in 13 cases (3.25%), second operation to remove hematoma in 9 cases (2.25%), postoperative circumoral herpes simplex virus infection in 25 cases (6.25%), and all complications were cured after symptomatic treatment. Postoperative hydrocephalus disappeared in 261 cases. ConclusionSurgical operation is the first choice in the treatment of giant acoustic neuromas. Under the auxiliary of neural electrophysiological monitoring, the microsurgery operation via suboccipital retrosigmoid approach for giant acoustic neuromas has extremely low mortality and high preservation rate of facial nerve function.