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At least 271 records · Page 15Linked to original sources
PubMed1999

Nerve regeneration through side-to-side neurorrhaphy sites in a rat model: a new concept in peripheral nerve surgery.

Despite great improvement and refinements in nerve repair techniques, there were still problems in repair of peripheral nerve injuries for which proximal stumps were not available. In these circumstances for which classic end-to-end neurorrhaphy was impossible, new treatment modalities, benefiting by an adjacent healthy nerve, have been under investigation to overcome this problem. Therefore, end-to-side nerve repair with its modifications came to view and axonal passages through this site were shown. Moreover, the results were unsatisfactory or necessitating sacrifice of another healthy nerve. Three groups, containing 10 rats each, were included in the study. First was the control group, with end-to-end repair of the peroneal nerve. Second was the end-to-side repair group, in which the distal stump of the peroneal nerve trunk was anastomosed to the lateral side of the tibial nerve. The third was the side-to-side repair group. In this technique, 1-mm diameter epineural windows, both from peroneal and tibial nerve trunks facing each other, were removed and side-to-side neurorrhaphy was performed. After 3 weeks, as the second step, the peroneal nerve was sectioned proximally. At 2, 4, 8, 12, 20, and 28 weeks, functional assessment of nerve regeneration was performed by using walking track analysis. The number of myelinated fibers and fiber diameters were measured and an electron microscopic evaluation was carried out. Statistically, both in morphometric and gait analysis, the differences in values between the groups were significant in favor of the control group, followed by the side-to-side group. The study showed that axonal passage was possible with side-to-side technique and the functional results were satisfactory and superior to the end-to-side technique. Continuous supply of neurotrophic factors from their target cells was the probable cause of superior functional return in side-to-side repair, because both joining nerves were intact and healthy during the anastomosis procedure and after 3 weeks. It was concluded that this technique could be indicated in salvage of nerves in cases for which any intermediate segments would be removed, as in tumor ablation surgery, harvesting of nerve grafts, or both.

Animals↗
PubMed2004

Enhancement of nerve regeneration and orientation across a gap with a nerve graft within a vein conduit graft: a functional, stereological, and electrophysiological study.

In this study, the right sciatic nerves of 40 rats were used to determine whether a nerve graft within a vein graft might accelerate and facilitate axonal regeneration, compared with a nerve graft alone. The animals were separated into four groups, as follows: group 1, sham control; group 2 (control), segmental nerve resection and no repair; group 3, segmental nerve resection and nerve grafting; group 4, segmental nerve resection and reconstruction with a nerve graft within a vein conduit graft. For all groups, sciatic functional indices were calculated before the operation and on postoperative days 7 and 90. On postoperative day 90, the sciatic nerves were reexposed and nerve conduction velocities were recorded. The sciatic nerves were harvested from all groups for counting of the myelinated axons with a stereological method. No statistically significant differences with respect to return of gait function, axon count, or nerve conduction were noted between groups 3 and 4 (p > 0.05). However, functional recovery in group 4 on postoperative day 90 was significant, compared with group 2 (p < 0.05); the recovery difference between groups 2 and 3 was not significant (p > 0.05). This study was not able to demonstrate any functional benefits with the use of a nerve graft within a vein graft, compared with standard nerve grafting.

Animals↗
PubMed2004

The influence of motor axon misdirection on muscle contraction force in early nerve repair in a rat sciatic nerve model.

We examined the influence of misdirection of regenerating motor axons toward the distal sensory Schwann tubes on the muscle contraction force in early nerve repair using a rat sciatic nerve model. At 0, 1, 2, 4 and 8 weeks after severing the tibial, peroneal and sural nerves, the proximal stump of the tibial nerve was anastomosed with the distal stumps of both the peroneal and sural nerves using tubulisation (n=10 in each of five groups). We intentionally used the distal stump of the sural nerve (a sensory nerve) to induce regeneration in motor axons from the proximal tibial nerve stump toward the distal sensory nerve stump. Twenty-four weeks after nerve repair, isometric contraction force and wet weight of the anterior tibial muscle were measured, and the numbers of regenerated myelinated axons (motor and sensory) in the distal sural and peroneal nerves were counted. The rates of sural nerve regeneration were significantly higher at weeks 0 and 1 than at the later repair times. However, muscle contraction force and muscle wet weight did not differ significantly between groups in which nerves were repaired within four weeks of severance. These results indicate that peripheral nerve repair within four weeks of severance does not influence the muscle contraction force of single muscle despite the misdirection of motor axons toward the distal sensory Schwann tubes.

Anastomosis, Surgical↗
PubMed1980

An evaluation of nerve repair with nerve allografts in normal and immunologically tolerant rats.

Schwann cells survive longer in allografts of ganglia that contain minor, rather than major and minor, transplantation antigens. The authors have investigated whether a nerve allograft with minor antigens would be superior to one with major and minor incompatibilities in aiding in the repair of injured nerve. A segment of host peroneal nerve was removed from rats and replaced with a peroneal nerve allograft that contained either minor or major and minor antigens. The results showed that in normal rats, host nerve fibers could functionally regenerate through (that is, grow through and reinnervate muscle) nerve allografts 2 cm but not 4 cm in length, irrespective of the antigens the allografts contained. Host nerve fibers could, however, regenerate through 4-cm nerve allografts if the hosts were rendered immunologically tolerant of the transplantation antigens of the nerve donors. Furthermore, when sensitized lymphoid cells were injected into tolerant rats bearing functional nerve allografts, Schwann cell rejection and demyelination occurred in the graft but host nerve fibers remained. It is concluded that minor antigens alone are as potent as major and minor antigens together in evoking an immune response that prevents functional regeneration through long lengths of nerve allografts. Host nerve fibers can, however, regenerate through such nerve allografts if the hosts are immunosuppressed.

Animals↗
PubMed2006

Restoration of shoulder abduction by transfer of the spinal accessory nerve to suprascapular nerve through dorsal approach: a clinical study.

BACKGROUND: In recent years, transfer of the spinal accessory nerve to suprascapular nerve has become a routine procedure for restoration of shoulder abduction. However, the operation via the traditional supraclavicular anterior approach often leads to partial denervation of the trapezius muscle. The purpose of the study was to introduce transfer of the spinal accessory nerve through dorsal approach, using distal branch of the spinal accessory nerve, to repair the suprascapular nerve for restoration of shoulder abduction, and to observe its therapeutic effect. METHODS: From January to October 2003, a total of 11 patients with a brachial plexus injury and an intact or nearly intact spinal accessory nerve were treated by transferring the spinal accessory nerve to the suprascapular nerve through dorsal approach. The patients were followed up for 18 to 26 months [mean (23.5 +/- 5.2) months] to evaluate their shoulder abduction and function of the trapezius muscle. The outcomes were compared with those of 26 patients treated with traditional anterior approach. And the data were analyzed by Student's t test using SPSS 10.5. RESULTS: In the 11 patients, the spinal accessory nerves were transferred to the suprascapular nerve through the dorsal approach successfully. Intact function of the upper trapezius was achieved in all of them. In the patients, the location of the two nerves was relatively stable at the level of superior margin of the scapula, the mean distance between them was (4.2 +/- 1.4) cm, both the nerves could be easily dissected and end-to-end anastomosed without any tension. During the follow-up, the first electrophysiological sign of recovery of the infraspinatus appeared at (6.8 +/- 2.7) months and the first sign of restoration of the shoulder abduction at (7.6 +/- 2.9) months after the operation, which were earlier than that after the traditional operation [(8.7 +/- 2.4) months and (9.9 +/- 2.8) months, respectively; P < 0.05]. The postoperative shoulder abduction was 62.8 degrees +/- 12.6 degrees after transfer of the spinal accessory nerve, better than that after the traditional (51.6 degrees +/- 15.7 degrees). All the 11 patients could extend and externally rotate the shoulder almost normally. CONCLUSIONS: The accessory nerve transfer through dorsal approach is a safe and reliable procedure for the treatment of brachial plexus injury. Its postoperative effect is confirmed, which is better than that of the traditional operation.

Accessory Nerve↗
PubMed1995

Nerve expansion. The optimal answer for the short nerve gap. Behavioral analysis.

Treatment of the short nerve gap remains a challenge for the reconstructive surgeon, but it is a clinical problem that can be addressed by nerve expansion. In the present study, the effects of slow nerve expansion on the walking behavior of the rat were examined. When expansion was applied on a normal sciatic nerve or on a transected nerve at either the proximal or the distal segments, permanent 30% elongation could be achieved. The recovered function from the expanded nerve stumps was compared with such classical methods of nerve reconstruction as nerve graft, coaptation under moderate tension, and tensionless repair. The results compared favorably between the expanded groups and the time-honored methods of nerve repair. Analysis of the behavioral data indicated that any amount of expansion affected the functional capabilities of the involved nerve. However, expansion of a normal nerve and/or proximal segment of a transected nerve was better tolerated than distal segment expansion, which suggests that the presence of an axon may have a beneficial effect in minimizing the deforming mechanical insult. Slow nerve expansion appears to have a definite role in the microsurgical management of the short nerve gap.

Animals↗
PubMed1996

Light-microscopic and electron-microscopic evaluation of short-term nerve regeneration using a biodegradable poly(DL-lactide-epsilon-caprolacton) nerve guide.

The aim of this study was to evaluate short-term peripheral nerve regeneration across a 10-mm. gap, using a biodegradable poly(DL-lactide-epsilon-caprolacton) nerve guide, with an internal diameter of 1.5 mm and a wall thickness of 0.30 mm. To do so, we evaluated regenerating nerves using light microscopy, transmission electron microscopy and morphometric analysis after implantation of 12-mm nerve guides in the sciatic nerve of the rat. Evaluation times ranged from 3-10 weeks. Three weeks after reconstruction, myelinated nerve fibers could be observed in the distal nerve stump. Ten weeks after reconstruction, the regenerating nerves already resembled normal nerves. In conclusion, we show that poly(DL-lactide-epsilon-caprolacton) nerve guides can be successfully applied in the reconstruction of severed nerves in the rat model. Furthermore, we have observed the fastest nerve regeneration described thus far, after reconstruction using a biodegradable nerve guide.

Animals↗
PubMed1992

Neurinoma of the third, fourth, and sixth cranial nerves: a survey and report of a new fourth nerve case.

A rare case of trochlear nerve neurinoma is described. Including this case, the number of reported intracranial tumors arising from the sheaths of the third, fourth, and sixth cranial nerves is 38. By site and relationship to the nerve segment, they fall into three groups: cisternal, cisternocavernous, and cavernous. In cisternal tumors of the third and sixth nerves, paresis of the nerve hosting the tumor is the unique nerve deficit; by contrast, in those of the fourth nerve, paresis of the trochlear nerve can be absent and that of the third nerve present. In the latter tumors, a peculiar ataxic hemiparesis syndrome is produced by midbrain compression. Cisternocavernous neurinomas often cause symptoms of intracranial hypertension, while cavernous neurinomas bring about two clinical features: paresis of one or more nerves of the cavernous sinus and a clinicoradiological orbital apex syndrome. At surgery, generally cisternal neurinomas are totally removed and the nerve source of the tumor identified; in cisternocavernous and cavernous neurinomas, total removal of tumor and identification of the parent nerve have been reported in only half of the cases. In the majority of parasellar neurinomas, clinical differences can be found between those arising from the nerves governing eye movement and those arising from the gasserian ganglion.

Abducens Nerve↗
PubMed2006

Feasibility of forearm ultrasonography-guided nerve blocks of the radial, ulnar, and median nerves for hand procedures in the emergency department.

STUDY OBJECTIVE: We determine the feasibility of forearm ultrasonography-guided nerve blocks of the radial, ulnar, and median nerves, performed by emergency physicians, to provide procedural anesthesia of the hand in the emergency department (ED). METHODS: This was a prospective study involving a convenience sample of 11 patients presenting to an adult ED with hand pathology requiring a procedural intervention. Adults 18 years and older who presented to the ED during the 3-month study period were eligible. Physicians performing the nerve blocks were attending physicians, ultrasonography fellows, or residents who had participated in a 1-hour training session. The participants underwent ultrasonography-guided nerve blocks in the forearm to provide anesthesia. Any additional anesthesia or analgesia required to perform the procedure in the anesthetized region was recorded. Subjects rated their pain on a 100mm visual analog scale before the nerve block and 15 minutes after the nerve block. The primary outcomes for feasibility were the percentage of cases completed without rescue anesthesia or analgesia and the median reduction in pain on the visual analog scale after the nerve block. Secondary outcomes for feasibility included the median time to completion of the entire nerve block procedure for each subject (from initiation of ultrasonography to completion of the last injection) and the percentage of participants wishing to have the same procedure for similar injuries in the future. Other secondary outcomes included the percentage of participants with complications during the procedure and at 3 months. RESULTS: All procedures (100%) were completed without additional anesthesia or analgesia. The median reduction in visual analog scale score was 5.0 cm (interquartile range 3.0, 8.0; P=.003). The median time to completion of nerve blocks was 9 minutes per patient (interquartile range 6 minutes 30 seconds, 10 minutes 0 seconds), with a median of 2 blocks per patient. Ten of 11 patients (92%) stated they would wish to have the ultrasonography-guided nerve block in the future for similar injuries. There were no immediate complications and no complications reported at 3 months. CONCLUSION: Attending physicians, fellows, and residents can perform forearm ultrasonography-guided nerve blocks of the radial, ulnar, and median nerves quickly, without additional anesthesia and with high patient satisfaction, after minimal training. Although pilot data are suggestive, randomized controlled trials are needed to determine efficacy and safety. Ultrasonography-guided nerve blocks to provide anesthesia for hand procedures appear to be feasible in the ED.

Adult↗
PubMed2003

Poly lactic acid--caprolactone copolymer tube with a denatured skeletal muscle segment inside as a guide for peripheral nerve regeneration: a morphological and electrophysiological evaluation of the regenerated nerves.

A biodegradable copolymer of poly L-lactic acid and epsilon-caprolactone (PLAC) was manufactured into a tube, in which a denatured skeletal muscle segment was placed longitudinally. This model tube was implanted as a guide to promote nerve regeneration across a 5 cm gap in the rabbit sciatic nerve. Five months after implantation, good nerve regeneration was found throughout the graft and in the distal host nerve. The population (29.6/16 x 10(2) microm(2)) of regenerated nerves in the graft was higher than that of the contralateral normal sciatic nerve (18.0/16 x 10(2) microm(2)). Regenerated nerve fibers extended to the distal host nerve. The number of myelinated fibers was 13.7/16 x 10(2) microm(2) at a level 1.5 cm from the distal suture. The diameters (below 2 microm) of most regenerated myelinated (nerves in the graft and in the distal host nerve were much smaller than those (6-8 microm) of normal nerves. Electrophysiological evaluation showed that the hindlimb muscle (gastrocnemius) was innervated by motor nerves in all animals 5 months after implantation. These results indicate that the PLAC tube with a denatured muscle segment inside provided good conditions for nerve fiber regrowth. The PLAC tube is thought to protect the denatured muscle segment from rapid dissociation in the host tissue.

Absorbable Implants↗
PubMed1988

An alternative to the classical nerve graft for the management of the short nerve gap.

Reconstruction of a short nerve gap by a nerve graft produces donor-site scarring, loss of donor nerve function, and neuroma formation. This study compared the regeneration achieved after 1 year in 16 monkeys across a 3-cm upper arm ulnar nerve gap with a bioabsorbable polyglycolic acid nerve conduit with the regeneration achieved with a classical interfascicular interpositional sural nerve graft. The results demonstrated electrophysiologic and histologic evidence of neural regeneration across the gaps in all experimental groups. The bioabsorbable nerve conduit groups and the sural nerve graft group had mean fiber diameters, amplitudes, and conduction velocities each significantly less than those of normal control ulnar nerves. There was, however, no significant difference between any of the experimental groups. Electromyography demonstrated recovery of 19 of the 28 (68 percent) intrinsic muscles studied. These results demonstrate that the primate peripheral nerve can regenerate across short nerve gaps when guided by an appropriate nerve conduit, suggesting that a single-stage biodegradable polyglycolic acid conduit may be used as an alternative to a short interfascicular nerve graft.

Anastomosis, Surgical↗
PubMed1996

Peripheral nerve elongation by laser Doppler flowmetry-monitored expansion: an experimental basis for future application in the management of peripheral nerve defects.

Nerve grafting often fails to achieve optimal functional results and is always associated with donor-site morbidity. Peripheral nerve elongation by the use of a tissue expander may provide a useful adjunct in the management of segmental nerve loss. In the present study, rabbit sciatic nerve (n = 40) was elongated by expansion while nerve blood flow was monitored by laser Doppler flowmetry. Elongation was possible up to 40 percent with preservation of clinical nerve function. Nerve conduction velocity of the expanded nerves decreased in a linear relation to elongation. The reduction in nerve conduction velocity may be secondary to the observed widening of the nodes of Ranvier and altered membrane properties after remyelination. Demyelination and remyelination of whole internodes and axonal degeneration occurred only sporadically. Thus laser Doppler flowmetry-monitored expansion provides a safe method for elongation of intact rabbit sciatic nerve while nerve function and axonal continuity are preserved. Further studies are needed before clinical use is considered. This technique may represent a favorable alternative to nerve grafting for the treatment of peripheral nerve defects.

Action Potentials↗
PubMed1998

[Allograft of frozen nerve in repairing sensory nerve defect].

To observe the effect of allogenic transplantation of deep frozen nerve in repairing sensory nerve defect, 22 patients who had received this type of treatment were followed up for 0.5-5 years. There were 18 males and 4 females in this group, and the average age was 28 years old. Thirty-six nerve defects including the common volar digital nerve, proper volar digital nerve were repaired by allograft of nerves stored at deep frozen (-80 degrees C). The storation period was ranged from 9 days to 1 years. The length of the nerves were 2 cm-12 cm. After follow-up for 3 years (ranged from 7 months-5 years), 23 cases of nerve allograft obtained excellent and good results (63.9%), 10 cases were fair (27.7%) and 3 cases were poor (8.3%). It was concluded that (1) frozen nerve is one of nice materials for repairing the nerve defect (< 5 cm); (2) the immunity of allogenenic nerve is weak; (3) the deep frozen storation can reduce the immunity of nerve; (4) the dimethyl sulfoxide can prevent the nerve tissue from injury by deep frozen; (5) the best temperature and period for deep frozen storation should be studied further.

Adolescent↗
PubMed2000

[The attractive effects of nerve regeneration chamber fluid and degenerated nerve segments on the growth and the migration of the cocultured dorsal root ganglion neuron].

OBJECTIVES: We intended in this study to investigate the neurotropic effects of regeneration chamber fluid (RCF) and the degenerated nerve segments from distal of the regeneration chamber on the dorsal root ganglion (DRG). METHODS: The capillary model was first tested for its reliability to form concentration gradient with a dye being contained in the capillaries. The tissue culture in RCF test was divided into two groups each with 8 DRGs implanted in 8 dishes. RCF was contained in capillaries inserted down to the bottom of the dishes with their lower ends at a distance of about 1 mm to the DRGs in the experimental group, and DMEM media was contained in the control group. Segments of degenerated sciatic nerve from distal of the regeneration chamber were implanted with DRGs at a distance of about 0.5 - 1 mm in the coculturing experiment. DRGs were observed for the direction of the growth of the cells and the fibres. RESULTS: While the capillary containing the dye was put down to the bottom of the culture dish coated with a piece of nylon pad, the red color slowly disseminated with heavier staining in the center and lighter staining in the peripheral portion. We believe this pattern of shade could simulate the concentration gradient of tropic factors in this model. There were significantly more nerve fibres growing from the DRGs towards the capillaries in 6 of the 8 dishes in the experimental group after 72 hours of culture. The tissue and nerve fibers grew evenly in the control group. 76.5% of all the nerve fibres were growing in the direction facing the degenerated nerve segments after 12 hours of coculturing, and only 33.3% of the nerve fibres growing in that direction in the control group. Cells from the DRGs migrated towards the degenerated nerve segments, yet they tended to avoid the normal nerve segments. The migration index of the cells was 0.98 in average in the coculturing experiment with the degenerated nerve segments, but only 0.43 in average with the normal nerve coculturing. CONCLUSION: The capillary model was effective in studying the chemotactic growth of nerve tissue. RCF and the degenerated nerve segments had definite neurotropic effects on DRGs tissue.

Animals↗
PubMed1989

Degeneration and regeneration of peripheral nerve in the rat trigeminal system: III. Abnormal sensory reinnervation of rat guard hairs following nerve transection and crush.

The present study was undertaken in an attempt to better understand the abnormalities of cutaneous sensibility that are present in patients following nerve injury with concomitant cutaneous denervation and subsequent reinnervation. Reinnervated intervibrissal pelage of the rat mystacial pad was studied in silver-impregnated sections 3 and 5 months after transecting and 2 and 5 months after crushing the infraorbital nerve. The sensory terminals on guard and vellus hairs were analyzed in serial paraffin sections and in thick frozen sections. In normal rat mystacial skin, approximately nine/ten of innervated guard hairs have a typical piloneural complex consisting of a palisade of highly regular lanceolate terminals surrounded by circularly arranged Ruffini terminals and free nerve endings (FNEs). The remaining one of ten innervated guard hairs has only circularly arranged presumptive FNEs and Ruffini terminals. Vellus hairs, either singly or in clusters, typically have only circularly arranged terminals that in many cases are simple FNEs. We first recognized abnormalities in innervation of hairs following nerve transection and fully expected nerve terminals to be completely normal following nerve crush. Almost all reinnervated sensory nerve terminals associated with guard hairs were markedly abnormal following nerve transection and quantitatively abnormal following nerve crush. Following nerve transection, lanceolate terminals were almost completely absent, and they were remarkably reduced in number following nerve crush. Vellus hairs when reinnervated typically lacked the complex circular presumptive Ruffini terminals. These findings may be in part the basis for the abnormal cutaneous sensory perceptions (dysasthesias and paresthesias) noted in human subjects following damage to nerves with subsequent sensory reinnervation of the skin.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2000

Gamma knife radiosurgery as a primary treatment for prolactinomas.

OBJECT: The purpose of this study was to estimate the efficacy of gamma knife radiosurgery (GKS) in controlling tumor growth and endocrinopathy associated with prolactinomas. METHODS: Between 1993 and 1997, 164 of 469 patients with pituitary adenomas treated by GKS harbored prolactinomas. The dose to the tumor margin ranged from 9 to 35 Gy (mean 31.2 Gy), and the visual pathways were exposed to a dose of less than 10 Gy. The mean tumor diameter was 13.4 mm. The mean follow-up time for 128 cases was 33.2 months (range 6-72 months). Tumor control was observed in all but two patients who underwent surgery 18 and 36 months, respectively, after GKS. Clinical cure was achieved in 67 cases. Clinical improvement was noted with a decrease in the hyperprolactinemia after GKS. Nonetheless, in 31 (29%) of 108 patients who were followed for more than 2 years no improvement in serum prolactin levels was demonstrated, although this could be normalized by bromocriptine administration after treatment. Nine infertile women became pregnant 2 to 13 months after GKS and all gave birth to normal children. There was no visual deterioration related to GKS. Five women experienced premature menopause. In these patients there was subtotal disappearance of the tumor and an empty sella developed. CONCLUSIONS: Gamma knife radiosurgery as a primary treatment for prolactinomas can be safe and effective both for controlling tumor growth and for normalization of prolactin hypersecretion. A higher margin dose (> or = 30 Gy) seemed to be associated with a better clinical outcome. Gamma knife radiosurgery may make prolactinomas more sensitive to the bromocriptine.

Humans↗
PubMed2002

Reconstruction of peripheral nerves using acellular nerve grafts with implanted cultured Schwann cells.

The bridging of nerve gaps is still one of the major problems in peripheral nerve surgery. The present experiment describes our attempt to engineer different biologic nerve grafts in a rat sciatic nerve model: cultured isogenic Schwann cells were implanted into 2-cm autologous acellular nerve grafts or autologous predegenerated nerve grafts. Autologous nerve grafts and predegenerated or acellular nerve grafts without implanted Schwann cells served as controls. The regenerated nerves were assessed histologically and morphometrically after 6 weeks. Predegenerated grafts showed results superior in regard to axon count and histologic appearance in comparison to standard grafts and acellular grafts. The acellular nerve grafts showed the worst histologic picture, but axon counts were in the range of standard grafts. The implantation of Schwann cells did not yield significant improvements in any group. In conclusion, the status of activation of Schwann cells and the stadium of Wallerian degeneration in a nerve graft might be key factors for regeneration, rather than total number of Schwann cells. Predegenerated nerve grafts are therefore superior to standard grafts in the rat model. Acellular grafts are able to bridge nerve gaps of up to 2 cm in the rat model, but even the addition of cultivated Schwann cells did not lead to results as good as in the group with autologous nerve grafts.

Animals↗
PubMed1997

Medial antebrachial cutaneous nerve: a new donor graft for repair of facial nerve defects at the skull base.

When grafting a facial nerve defect after resection of a skull base cancer, the use of the greater auricular nerve is generally contraindicated because of concern of malignant involvement. In the past, the sural nerve was used as a donor graft for reconstruction of the facial nerve. We have found a sensory branch of the median nerve of the upper arm, the medial antebrachial cutaneous (MAC) nerve, to be a suitable option for facial nerve grafting. The MAC nerve provides a good diameter match for the facial nerve and has branching to allow reconstruction of the distal facial nerve in the parotid bed. The length is adequate to graft from the brainstem to the distal facial branches. Loss of sensation is limited and well tolerated by the patient. The MAC nerve has been used in grafting in 15 patients with skull base disease and facial nerve defects. No complications have been encountered, and the functional return appears to be similar to other grafts. In our practice the MAC nerve is a valuable option for facial nerve repair at the skull base.

Adult↗