• Journal of Life Science
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• v.13 no.6
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• pp.950-957
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• 2003

The purpose of this study is to classify the contrast group and experiment group of a male white rat, and to identify a result of NFG's change that press the sciatic nerves injured peripheral ones for curing 1day, 3days, 5days and 7days. In contrast group, the nerve cells of immune-reaction were increased on 1 day and they were decreased for 3 days, 5 days, 7 days as a normal one. In experiment group, they were increased on 1 day but, decreased for 3 days, 5 days, 7 days more than contrast group. In conclusion, it is certain that the Needle TENS can make a NFG decrease and effect on the therapy.

• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.611-615
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• 2004

A neural prostheses can be designed to permit stimulation of specific sites in the nervous system to restore their functions, lost due to disease or trauma. This study focuses on the feasibility of optoelecronic stimulation into nervous system. Optoelectronic stimulation supplies, power and signal into the implanted optical detector inside the body by optics. It can be effective strategy especially on the retinal prosthesis, because it enables the non-invasive connection between the external source and internal detector through natural optical window 'eye'. Therefore, we designed an effective neural stimulating setup by optically based stimulation. Stimulating on the sciatic nerve of a rat with proper depth probe through optical stimulation needs higher ratio of current spreading through the neural surface, because of high impedance of neural interface. To increase the insertion current spreading into the neuron, we used a parallel low resistance compared to load resistance organic interface and calculated the optimized outer parallel resistance for maximum insertion current with the assumption of limited current by photodiode. Optimized outer parallel resistance was at a range of 500Ω-700Ω and a current was at a level between 580uA and 650uA. Stimulating current efficiency from initial photodiode induced current was between 47.5 and 59.7%. Various amplitude and frequency of the optical stimulation on the sciatic nerve showed the reliable visual tremble, and the action potential was also recorded near the stimulating area. These result demonstrate that optoelectronic stimulation with no bias can be applied to the retinal prosthesis and other neuroprosthetic area.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.17 no.1
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• pp.96-107
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• 1995

The purpose of this experimental study was to examine and compare the regeneration capacity between crushed nerve & transected nerve. For this study, 20 Sprague-Dawley female albino rats were used as experimental animals and divided into two groups. In group 1, the sciatic nerves were crushed 6mm. in length for 1 min. using maximum force with a needle holder. In group 2, the sciatic nerves were resected 6mm. in length and the gaps were encased by inserting the proximal and distal stumps into each end of silicone tubes. The animals were sacrificed 1 month & 2 months after the experiment. All specimens were fixed in 2.5% glutaraldehyde and 1% Osmium tetroxide solution then embedded in epon 812 and were cross-sectioned at $1{\mu}m.$ After these procedures, specimens were observed under Light microscope. The results obtained were as follows. 1. Group 1 showed greter diameters of regenerating nerves than group 2. 2. Group 1 showed greater number of axons than group 2.

• Archives of Plastic Surgery
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• v.36 no.6
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• pp.799-802
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• 2009

Purpose: Schwannoma is one of common neoplasm in the central and peripheral nervous systems. However, schwannoma of sciatic nerve is rare, especially large schwannoma arising in sciatic nerve is extremely rare. This is a report of our experience with large schwannoma arising in sciatic nerve with minimal neurologic symptoms. Methods: A 65 - year - old man presented with palpable mass in middle portion of posterior thigh. No definitive neurologic deficits were detected on physical examinations. CT and sonography showed well - defined mass with large dimension. The mass was excised and confirmed histologically as a schwannoma. In postoperative period, NCS and EMG were followed. Results: The patient complained of difficulty in dorsiflexion of ipsilateral ankle joint postoperatively. NCS and EMG obtained immediately and showed sciatic neuropathy. After 2 months postoperatively, NCS and EMG were followed and abnormal findings of previous NCS and EMG were not found. Dorsiflexion of ankle joint was improved to normal range of motion. Conclusion: We report a rare case of large schwannoma arising in sciatic nerve with no definitive neurologic symptoms.

• Journal of Trauma and Injury
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• v.26 no.3
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• pp.229-232
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• 2013

Traumatic fracture-dislocations of the hip frequently result from high-energy injury, and hip dislocations are commonly associated with severe concomitant injuries. Sciatic nerve injury often accompanies traumatic fracture-dislocation of the hip, but neurologic examination at the time of injury is difficult in severely traumatized patients with decreased consciousness. We present such a case of multiple traumas with traumatic hip dislocation and sciatic nerve injury after reduction, and we found that magnetic resonance image (MRI) played an important role in developing a management plan.

• The Korean Journal of Pain
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• v.22 no.2
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• pp.186-190
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• 2009

Sciatic nerve block is frequently used for anesthesia or analgesia during lower leg surgery or chronic lower leg pain syndrome. Recently, a lot of ultrasound-guided peripheral nerve block has been reported because there are several benefits compared to blind technique. We performed ultrasound-guided right sciatic nerve block successfully to the patient who has been suffering from right buttock pain after previous radiation therapy.

• The Journal of the Korean bone and joint tumor society
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• v.3 no.2
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• pp.80-88
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• 1997

Malignant tumors of extremeties involving major neurovascular structures have been treated by amputation. However recent development of diagnostic tools(CT, MRI etc.), surgical techniques, anticancer chemotherapeutic agents, and radiation techniques allow surgeons to treat malignant tumors in the limb without amputation. It has been reported that a local application of low-heat to the tissue with tumor can kill tumor cells. It is, however, not known if the attendant neural and vascular injuries may be recovered. The present study was, therefore, undertakn to address this question in rabbit sciatic nerves. A low-heat injury to the sciatic nerve was induced by perfusing the nerve with $60^{\circ}C$ saline for 30 minutes and the courses of functional and morphological recovery of the nerve were evaluated for 16 weeks. The results are summerized as follows : 1. In the electromyographic nerve conduction test the average amplitude was markedly attenuated at 4 and 8 weeks after the low-heat treatment, but it progressively increased to the level 89.5% of the control at 16 week post-treatment. The average latency in the control group was 0.62 msec. The latency in the experimental group was much longer than this at 4 and 8 week post-treatment, but it progressively reverted to the control level, showing 0.622 msec at 16 weeks. 2. In the needle EMG, many fibrillation potentials and positive sharp waves were appeared until 8 weeks post-treatment. After 16 weeks, however, no fibrillation potential was observed. 3. In the early phase of post-treatment period, the myelinated nerve fibers contained many vacuoles and the number of myelinated nerve fibers appeared to be considerably reduced. However, as time goes myelinated nerve fibers were regenerated, such that after 16 weeks the histologic appearance of the nerve was similar to that of the control group.

• The Korean Journal of Pain
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• v.5 no.1
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• pp.44-51
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• 1992

This study examined the microscopic changes following irradiation of infrared low dose laser on injured sciatic nerves of rats. In these days, many clinicians use the low dose laser therapy in pain clinicians use the low dose laser therapy in pain clinic on various fields and dieases. But the basic mechanism and indications were not known completely. Low-dose IR(infrared) laser irradiation applied to a crushed injured sciatic nerve of rats in the right leg in bilaterally inflicted crush injury. The results were as follows 1) There are a little histological differences between laser treated group and nontreated group. 2) Low power IR-laser irradiation, when applied to the injured sciatic nerve, increased vascularization and relatively well conserved tissue organization. 3) There are little histological difference in distal muscle biopsy, but atrophic muscle fibers were seen partially. 4) We found out that more hypertrophic epineurium was present in laser-treated group.

• Archives of Reconstructive Microsurgery
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• v.12 no.1
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• pp.1-12
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• 2003

The bridging of nerve gaps is still one of the major problems in peripheral nerve surgery. To evaluate the role of silicon tube in nerve regeneration, gaps were made by resection of tibial components of sciatic nerves of twenty-five New Zealand rabbits. The gaps were divided into five groups. In group I, the tibial components of sciatic nerves were isolated and the incision immediately closed. In group II, 1-cm segments of the nerve were removed and the silicon tubes filled with autogenous skeletal muscle were sutured in place. In group III, 1-cm segments of the nerve were removed and the silicon tubes filled without muscle were sutured in place. In group IV, 2-cm segments of the nerve were removed and the silicon tubes filled with autogenous skeletal muscle were sutured in place. In group V, 2-cm segments of the nerve were removed and the silicon tubes filled without muscle were sutured in place. At 16th week, the eletromyography, the light and transmission electron microscopy were performed. Nerve conduction study stimulating sciatic nerve proximal to the lesion and recording at gastrocnemius muscle showed that the compound muscle action potentials of the group II with 1 cm nerve defect filled with muscle were higher amplitudes than the group III without muscle. Compound muscle action potentials of the group IV with 2 cm defect filled with muscle showed similar results in comparison with the group V. The light and transmission electron microscpy showed that a good morphological pattern of nerve regeneration in 1 cm gap than 2 cm and in gap with muscle than gap without muscle.

• Polymer(Korea)
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• v.32 no.1
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• pp.49-55
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• 2008

It is recognized that Schwann cells (SC) are essential for peripheral nerve development and regeneration. SIS (small intestinal submucosa) consists of some growth factors which can stimulate cell activity without immune rejection responges. SCs were harvested from the femurs and tibias of female Fischer rat and then suspended with $2{\times}10^6$ cell/sponge in SIS sponge. Fischer rat received an implant consisting of the SCs and the SIS sponge at the place of a 5 mm gap created by the sciatic nerve resection. Thin sections were stained with H &E staining and immunostaining of S-100, GFAP and NF after 1, 2, and 4 weeks. It was observed that the effects of the SIS sponge with SCs on neuroinduction(Group II, with scaffold & cell) are strong as much as uninjured model(Control I), and significantly stronger than SIS sponge model (Group 1, with scaffold only) and blank model (Control II). In conclusion, these results suggest that SIS sponge filled with SCs may have an important role for peripheral nerve regeneration of tissue engineering.