• Journal of the Korean Geosynthetics Society
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• v.21 no.2
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• pp.39-48
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• 2022

Unlike the horizontal strut, the corner strut causes bending behavior by the installation angle when soil pressure occurs, so there is a limit to its application as a elasto plastic method that requires only the axial stiffness of struts. Therefore, this study attempted to approach a method of modifying axial stiffness data to present an analysis method for corner struts in elasto plastic method, and linear elasticity analysis was used for this. And, through Linear elasticity analysis, axial stiffness data for corner struts installed at the actual site were calculated. The behavior of the retainingwall was confirmed by applying the calculated axial stiffness data of corner struts to elasto plastic method, and its applicability was evaluated by comparing it with the measurement results and the finite element analysis results. As a result of the study, when the axial stiffness data of the corner struts was applied using Linear elasticity analysis(Case 1, Case 3), the axial stiffness data decreased to 9% to 17% compared to the general method of applying the axial stiffness of the struts(Case 2, Case 4), and the displacement of the retainingwall increased to 25.33% to 64.42%. Comparing this result with the measurement results, when Linear elasticity analysis was used(Case 1, Case 3), the behavior of the retainingwall during the elasto plastic method was better shown.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.2
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• pp.154-163
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• 2013

Adhesive bonding and plastic welding have been widely used to join two plastic materials together. The goal of this paper is to determine a proper joining technology of a pair of flat panel (FP) photobioreactor (PBR) case. The material of the FP PBR case is polycarbonate (PC) plate. Two types of adhesion, including acryl adhesive and two-part epoxy adhesive, as well as two types of plastic welding technology, including ultrasonic welding and thermal welding, are employed for joining of PC plates. In order to influence of the adhesion and welding conditions on the joining characteristics of the PC plates in operational conditions of the FP PBR case, the morphology in the vicinity of the joined region as well as the water and pressure resistance characteristic are investigated. In addition, the variation of the bonding strength of the joined region and deformation behaviors in the vicinity of the joined region according to the adhesion and welding conditions is examined via the lap-shear test. From the results of basic experiments, proper joining technologies are chosen. Using the chosen joining technologies, the FP PBR case are fabricated to perform full-scale durability experiment. The results of the full-scale durability experiment have been shown that the chosen joining technologies can be applicable to fabricate the FP PBR case.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.438-444
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• 2011

Purpose: Adipose-derived stromal cells (ASCs) are readily harvested from lipoaspirated tissue or subcutaneous adipose tissue fragments. The stromal vascular fraction (SVF) is a heterogeneous set of cell populations that surround and support adipose tissue, which includes the stromal cells, ASCs, that have the ability to differentiate into cells of several lineages and contains cells from the microvasculature. The mechanisms that drive the ASCs into the osteoblast lineage are still not clear, but the process has been more extensively studied in bone marrow stromal cells. The purpose of this study was to investigate the osteogenic capacity of adipose derived SVF cells and evaluate bone formation following implantation of SVF cells into the bone defect of human phalanx. Methods: Case 1 a 43-year-old male was wounded while using a press machine. After first operation, segmental bone defects of the left 3rd and 4th middle phalanx occurred. At first we injected the SVF cells combined with demineralized bone matrix (DBM) to defected 4th middle phalangeal bone lesion. We used P (L/DL)LA [Poly (70L-lactide-co-30DL-lactide) Co Polymer P (L/DL)LA] as a scaffold. Next, we implanted the SVF cells combined with DBM to repair left 3rd middle phalangeal bone defect in sequence. Case 2 was a 25-year-old man with crushing hand injury. Three months after the previous surgery, we implanted the SVF cells combined with DBM to restore right 3rd middle phalangeal bone defect by syringe injection. Radiographic images were taken at follow-up hospital visits and evaluated radiographically by means of computerized analysis of digital images. Results: The phalangeal bone defect was treated with autologous SVF cells isolated and applied in a single operative procedure in combination with DBM. The SVF cells were supported in place with mechanical fixation with a resorbable macroporous sheets acting as a soft tissue barrier. The radiographic appearance of the defect revealed a restoration to average bone density and stable position of pharyngeal bone. Densitometric evaluations for digital X-ray revealed improved bone densities in two cases with pharyngeal bone defects, that is, 65.2% for 4th finger of the case 1, 60.5% for 3rd finger of the case 1 and 60.1% for the case 2. Conclusion: This study demonstrated that adipose derived stromal vascular fraction cells have osteogenic potential in two clinical case studies. Thus, these reports show that cells from the SVF cells have potential in many areas of clinical cell therapy and regenerative medicine, albeit a lot of work is yet to be done.

• Archives of Plastic Surgery
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• v.37 no.4
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• pp.396-399
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• 2010

Purpose: In hand injury, pedicle is usually damaged by avulsion injury or crushing injury. Because of postoperative pedicle obliteration, it is often hard to save the injured hand and fingers, even after successful replantation. The author introduces three cases of extensive hand injury, and successful results after applicatoin of multiple venous grafts to these patients. Methods: In all cases there was no circulation in any finger. In the first case, some vessels were extracted, so venous graft was applied to two sites of severely damaged venous sites. In the second case, venous grafts were applied to all four digital arteries of all fingers except thumb which got severely crushed, and two sites of dorsal veins. In the third case, venous graft was applied to all four digital arteries of all five fingers, and two sites of dorsal veins and palmar veins each. Results: In all cases, survival of hands and fingers was successful. In the second case, however, amputation in thumb and little finger at DIP joint level was inevitable, because of its severe damage, and the large dorsal defect on index finger was filled with DIEP free flap. Thumb was reconstructed with toe-to-thumb free flap, and additional debulking procedures and contracture release is furtherly needed. In the first case, additional surgery was done, as FDP tendon got re-ruptured, but in long term follow-up, satisfactory range of motion was attained. In the third case, FTSG on dorsal skin region was planned. as flap on dorsal area got partial necrosis. Conclusion: In hand injury, there are many structures to be repaired, but sometimes venous graft is avoided for its long operating time. Even though the length of damaged vessel is enough for anastomosis, the endothelium is often damaged (zone of injury). In extensive hand injury, successful reconstruction would be possible with active venous graft to all vessels suspicious for damage.

• Korean Journal of Head & Neck Oncology
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• v.36 no.2
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• pp.33-36
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• 2020

Cutaneous horn is the clinical entity, which is circumscribed, conical, markedly hyperkeratotic lesion in which the height of the keratotic mass amounts to at least half of its largest diameter. It may be associated with many different pathological lesions. It is a relatively rare and a kind of epidermal tumor that generally appears as a conical projection. Here, we report rare case of congenital cutaneous horn. A 39-month-old female Korean patient presented at our clinic with a mass at the tip of her nose present since birth. Under general anesthesia, cutaneous horn of nasal tip was completely excised without any complications. The operation site was small enough to perform a primary closure, without any nasal deformity. Histopathologically, it was reported as a fibroepithelial polyps. After operation, there is no evidence of recurrence at 16 months of follow-up.

• Archives of Craniofacial Surgery
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• v.11 no.2
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• pp.120-123
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• 2010

Purpose: Epinephrine itself exhibits some cardiotoxicity. However, it rarely induces cardiomyopathy when used in standard doses during surgery for local hemostasis. This paper reports a rare case of stress-induced cardiomyopathy in a young woman after the local infiltration of epinephrine. Methods: Corrective rhinoplasty was planned in a 20-year-old woman. Lidocaine mixed with epinephrine 1:100,000 was injected around the skin of the nose and nasal septum after inducing anesthesia, which resulted in sinus tachycardia and hypotension. Postoperative ECG showed a T wave inversion in the lead V2 and echocardiography revealed transient hypokinesia in the cardiac apex. Cardiac enzyme was mildly elevated. Results: Symptoms and laboratory findings improved considerably, and the patient was discharged from hospital without complications on the sixth day after surgery. Conclusion: The prognosis of catecholamine-induced cardiomyopathy is generally favorable. However, it is important to be aware of the possible adverse effects of local epinephrine infiltration. This case highlights the need for caution when using epinephrine.

• Archives of Plastic Surgery
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• v.33 no.6
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• pp.761-763
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• 2006

Purpose: Malignant peripheral nerve sheath tumors most often arise from the anatomically discernible peripheral nerve or neurofibroma. Methods: A 55-year-old man had a rapidly growing pedunculated large mass on the sacrolumbar junction for 2 years. He has congenital neurofibromatosis type I. He had multiple caf-au-lait spots and multiple neurofibromas on the entire body. The mass developed from a subcutaneous nodule on the sacrolumbar junction and grew rapidly. The preoperative punch biopsy revealed a malignant peripheral nerve tumor. The mass was completely excised with 1 cm free margin above the deep fascial plane. Results: There was no evidence of recurrence of tumor for 19 months of follow-up examination. Conclusion: Malignant peripheral nerve sheath tumor is very rare and has unique feature. We report a successful case of malignant peripheral nerve sheath tumor with the review of the literatures.

• Archives of Plastic Surgery
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• v.32 no.3
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• pp.389-392
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• 2005

A case of visual loss following cranio-maxillofacial trauma is reported. The patient had acute optic nerve injury associated with a fracture of the right zygomaticomaxillary and fronto-naso-ethmoido-orbital bone and epidural hematoma on the right temporal lobe of brain. Bony fragments compressing the optic nerve on lateral side was identified on computed tomography. Decompression of the optic nerve combined with evacuation of epidural hematoma has been performed via transfrontal craniotomy. The patient had complete recovery of visual acuity without any complications. The role of optic nerve decompression in the management of patients with traumatic optic neuropathy is discussed. Surgical indication is controversial and the procedure should be considered only within the context of the specific indication of the individual patient.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.241-244
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• 2006

Idiopathic scrotal calcinosis is rare entity, characterized by the presence of multiple, firm nodules within the dermis of scrotal skin. The lesions are evident as asymptomatic, round, firm, yellowish papules, from several millimeters up to 1 cm in diameter, with a tendency to occur symmetrically. Because polypoid formation of the calcified cysts is unusual in scrotal calcinosis, we report our experience of a case of scrotal calcinosis with cysts having polypoid appearence. A 34-year-old man was admitted to our department with painless, firm, widespread nodules within the scrotum. Patient started to have these lesions at puberty and progressed to a polypoid form over time. There was neither surgical nor medical treatment had been attempted before our treatment. Physical examination revealed localized polypoid cysts in addition to multiple small, firm nodules within the scrotal skin. No underlying anomalies were detected in the physical examination and laboratory analysis. We experienced the treatment of polypoid idiopathic scrotal calcinosis and a case is presented with the review of literatures.

• Archives of Plastic Surgery
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• v.34 no.3
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• pp.406-408
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• 2007

Purpose: Despite a high frequency of acquired nail disease, congenital absence of the nail, also called as anonychia, is a rare anomaly. It may be seen as an isolated of phalangeal bone(ectrodactyly), nail-patella syndrome, birth trauma, impaired peripheral circulation, alopecia areata, and pemphigus, idiopathic atrophy of the nail, bullous drug eruptions, periodic shedding, lichen planus, Stenvens-Johnson syndrome and so forth. Methods: We have experienced a rare case of 40-day-old neonate, suffering from intrauterine growth retardation, but without familial history, chromosomal anomalies or any other diseases. Results: There was no nail on left 5th finger and distal phalangeal bone of same finger. So, We diagnosed as Congenital Anonychia with ectrodactyly of 5th Finger. Conclusion: We report this case as congenital anonychia of 5th finger which have developed from underlying distal phalangeal ectrodactyly. We also review other reported cased in the literatures.