• Archives of Plastic Surgery
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• v.36 no.5
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• pp.605-610
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• 2009

Purpose: Substantial tissue necrosis after snake bites requiring coverage with flap surgery is extremely rare. In this article, we report 7 cases of soft tissue defects in the upper and the lower extremities caused by snake bites, which needed to be covered with flaps. Among the vast mass of publications on snake bites there has been no report that focuses on flap coverage of soft tissue defects due to snake bite sequelae. Methods: Seven cases of soft tissue defects with tendon, ligament, or bone exposure after snake bites were included. All patients were males without comorbidities, the average age was 35 years. All of them required coverage with a flap. In 6 cases, the defect was localized on the upper extremity, in one case the lesion was on the lower extremity. Local flaps were used in 6 cases, one case was covered with a free flap. The surgical procedures included one kite flap, one cross finger flap and digital nerve reconstruction with a sural nerve graft, one reverse proximal phalanx island flap, one groin flap, one adipofascial flap, one neurovascular island flap, and one anterolateral thigh free flap. The average interval from injury to flap surgery was 23.7 days. Results: All flaps survived without complication. All patients regained a good range of motion in the affected extremity. Donor site morbidities were not observed. The case with digital nerve reconstruction recovered a static two point discrimination of 7 mm. The patient with foot reconstruction can wear normal shoes without a debulking procedure. Conclusion: The majority of soft tissue affection after snake bites can be treated conservatively. Some severe cases, however, may require the coverage with flap surgery after radical debridement, especially, if there is exposure of tendon, bone or neurovascular structures. There is no doubt that definite coverage should be performed as soon as possible. But we also want to point out that this principle must not lead to a premature coverage. If the surgeon is not certain that the wound is free of necrotic tissue or remnants of venom, it is better to take enough time to get a proper wound before flap surgery in order to obtain a good functional and cosmetic result.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.536-540
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• 2006

Purpose: The soft tissue injuries of the patellar area are difficult problems because of insufficient arterial blood supply and lack of muscle layer. There have been many methods for reconstructing the soft tissue injuries of the patellar area such as primary closure, skin graft, local flap and free tissue transfer. However, each method has some limitations in their application. After the first introduction, the fasciocutaneous flaps are widely used to reconstruct the soft tissue injuries. The saphenous nerve, one of the superficial sensory nerves in the lower leg, is supplied by the saphenous artery and its vascular network. We used the saphenous fasciocutaneous island flap to reconstruct the soft tissue injuries of the patellar area. Methods: From March 2002 to May 2005, we used the saphenous fasciocutaneous island flap to reconstruct the soft tissue injuries of the patellar area. The flap was elevated with saphenous nerve, saphenous vein and saphenous artery and its vascular network. The flap donor site was reconstructed with primary closure or split-thickness skin graft. Results: Five cases survived completely but 1 case developed partial necrosis of the skin on the upper margin of the flap. However, the necrosis was localized on skin layer, and we reconstructed with debridement and split-thickness skin graft only. After the operation, there was no contracture or gait disturbance in any patient. Conclusion: In conclusion, the saphenous fasciocutaneous island flap is safe, comfortable and effective method to reconstruct the soft tissue injuries of the patellar area.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.181-181
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• 2006

We developed a novel method to fabricate a nerve guide conduit (NGC) with the porosity of submicron pore sizes (to prevent fibrous tissue infiltration) and hydrophilicity (for effective oxygen and nutrient permeation) using poly(lactic-co-glycolic acid) (PLGA) and Pluronic F127 by a modified immersion precipitation method designed by our laboratory. It was recognized that the hydrophilized PLGA/F127 (3 wt%) tube can be a good candidate as a NGC from the analyses of its morphology, mechanical strength, hydrophilicity, model nutrient permeability and in vivo nerve regeneration behavior using a rat model.

• Journal of Oral Medicine and Pain
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• v.41 no.4
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• pp.145-154
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• 2016

Transcutaneous electrical nerve stimulation (TENS) is one of the representative physiotherapical modalities used for the treatment of various musculoskeletal disorders by the application of electrical stimuli. In dental practice, it has long been used in the treatment of acute and chronic orofacial pain conditions including temporomandibular disorders. TENS is the delivery of therapeutic electrical stimuli with a variety of electrical intensity, frequency and duration to stimulate peripheral nerve through surface electrodes with various form and placement. While controversy still remains over the clinical effectiveness and application of TENS, basic understanding of its electrical properties and the expected biological reactions is important to increase the therapeutic effect and decrease the risk of possible side effects. This review, therefore, focuses on basic understanding of TENS including its underlying mechanisms and stimulation parameters.

• The Korean Journal of Pain
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• v.26 no.2
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• pp.111-124
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• 2013

Ultrasound has emerged to become a commonly used modality in the performance of chronic pain interventions. It allows direct visualization of tissue structure while allowing real time guidance of needle placement and medication administration. Ultrasound is a relatively affordable imaging tool and does not subject the practitioner or patient to radiation exposure. This review focuses on the anatomy and sonoanatomy of peripheral non-axial structures commonly involved in chronic pain conditions including the stellate ganglion, suprascapular, ilioinguinal, iliohypogastric, genitofemoral and lateral femoral cutaneous nerves. Additionally, the review discusses ultrasound guided intervention techniques applicable to these structures.

• Journal of Biomedical Engineering Research
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• v.45 no.4
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• pp.173-178
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• 2024

We present an improved biphasic electrical nerve stimulator designed to overcome limitations. Traditional electrical nerve stimulators lacking a microcontroller unit (MCU) have restrictions in terms of frequency, pulse duration, and amplitude control, making them insufficient for medical applications requiring a broader range of pulse specifications. To address this, we developed a stimulator with enhanced capabilities. By not using an MCU, the design reduces power consumption and the required area, simplifying the overall design and increasing efficiency. In addition, our approach optimizes oscillator parameters to achieve wide frequency and pulse duration ranges. Specifically, we expanded the frequency range of the stimulator up to from 1 mHz to 100 kHz and the pulse duration up to from 5 ㎲ to 500 s. Improved amplitude control mechanisms were implemented for adjustable and high biphasic amplitudes. Furthermore, we added a balancing circuit to ensure proper discharging for tissue safety when biphasic pulses do not occur. The improved stimulator demonstrated an increase in operational range compared to traditional MCU-less designs, producing consistent biphasic pulses with adjustable amplitude and duration. The balancing circuit effectively managed discharging, reducing the risk of tissue damage and ensuring safety and efficacy.

• The Korean Journal of Physiology
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• v.15 no.2
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• pp.73-81
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• 1981

Experiments were conducted in ischemic decerebrate cats to study the effects of electroacupuncture and electrical stimulation of peripheral nerve on pain reaction. Flexion reflex was used as an index of pain. The reflex was elicited by stimulating the sural nerve(20 V, 0.5 msec duration) and recorded as a compound action potential from the nerve innervated to the semitendinosus muscle. Electroacupuncture was performed, using a 23-gauge hyperdermic needle, on the tsusanli point in the lateral upper tibia of the ipsilateral hindlimb. The common peroneal nerve was selected as a peripheral nerve which may be associated with electroacupuncture action, as it runs through the tissue portion under the tsusanli point. Both for electroacupuncture and the stimulation of common peroneal nerve a stimulus of 20 V-intensity, 2 msec-duration and 2 Hz-frequency was applied for 60 min. The results are summerized as follows: 1) The electroacupuncture markedly depressed the flexion reflex; this effect was eliminated by systemic application of naloxone $(0.02{\sim}0.12\;mg/kg)$, a specific narcotic antagonist. 2) Similarly, the electrical stimulation of the common peroneal nerve significantly depressed the flexion reflex, the effect being reversed by naloxone. 3) When most of the afferent nerves excluding sural nerve in the ipsilateral hindlimb were cut, the effect of electroacupuncture on the flexion reflex was not observed. Whereas direct stimulation of the common peroneal nerve at the proximal end from the cut resulted in a significant reduction of the flexion reflex, again the effect was reversible by naloxone application. 4) Transection of the spinal cord at the thoracic 12 did not eliminate the effect of peripheral nerve stimulation on the flexion reflex and its reversal by naloxone, although the effect was significantly less than that in the animal with spinal cord intact. These results suggest that: 1) the analgesic effect of an electroacupuncture is directly mediated by the nervous system and involves morphine-like substances in CNS, 2) the site of analgesic action of electroacupuncture resides mainly in the brainstem and in part in the spinal cord.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.1
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• pp.44-52
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• 1999

The purpose of this study was to investigate the distribution of CGRP immunoreactive nerve fibers in rat squamosomandibular joint with postnatal development. Squamosomandibular joint with adjacent tissue of 8 groups of rats(1, 5, 10, 15, 20, 25, 35-postnatal day and adult groups) were removed on bloc and processed for immunohistochemistry and were subjected to light microscopic examination. The results obtained were as follows; 1. The anterior portion of the articular disk was most densely innervated, followed by the posterior, lateral, and medial portions in each group. 2. Increase of CGRP immunoreactive nerve fibers was evident in 10, 15, 20 postnatal day groups. 3. Almost no CGRP immunoreactive nerve fibers were observed in articular surface of disk proper, mandibular fossa and condyle head of each group. These result suggest that CGRP immunoreactive nerve fibers increased in synovial membrane and peripheral portion of articular disk during 10-20 postnatal day may play a important role in squamosomandibular joint function after weaning period.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.6
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• pp.492-495
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• 2005

The role of cultured bone marrow stromal cells (BMSCs) in peripheral nerve regeneration was examined using an established rabbit peroneal nerve regeneration model. A 15-mm peroneal nerve defect was bridged with a vein filled with BMSCs $(1{\times}10^6)$, which had been embedded in collagen gel. On the contralateral side, the defect was bridged with a vein filled with collagen gel alone. When the regenerated tissue was examined 4, 8 and 12 weeks after grafting, the number and diameter of the myelinated fibers in the side with the BMSCs were significantly higher than in the control side without the BMSCs. This demonstrates the potential of using cultured BMSCs in peripheral nerve regeneration.

• Anatomy and Cell Biology
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• v.57 no.3
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• pp.392-399
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• 2024

The recurrent laryngeal nerve is a bilateral branch of the vagus nerve that is mainly associated with the motor innervation of the intrinsic muscles of the larynx. Despite its bilateral distribution, the right and left recurrent laryngeal nerves display unequal length due to embryological processes related to the development of the aortic arches. This length asymmetry leads to theories about morphological compensations to provide symmetrical functions to the intrinsic muscles of the larynx. In this study we investigated the developmental and cross-sectional morphometrics of the recurrent laryngeal nerves in human fetuses. Fifteen stillbirth fetuses donated to anatomical and medical research were used for investigation. Fetuses had intrauterine age ranging from 30 to 40 weeks estimated by biometry methods. Specialized anatomical dissection of the visceral block of the neck was performed to prepare histological samples of the recurrent laryngeal nerves in its point of contact with the larynx, and morpho-quantitative techniques were applied to evaluate the epineurium and perineural space of the recurrent laryngeal nerves. No statistical difference in the cross-sectional morphology of the epineurium and perineural space between right and left recurrent laryngeal nerves intra-individually was confirmed, however, we found evidence that these structures are under greater development in the left recurrent laryngeal nerve during 30 to 40 weeks of intrauterine life. Our data suggest that the nerves are under morphological development that possibly set the stage for accommodation of larger diameter and myelinization of the left recurrent laryngeal nerve during post-natal life.