• International Journal of Automotive Technology
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• 제5권1호
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• pp.33-46
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• 2004

A finite element model development of a 50th percentile male cervical spine is presented in this paper. The model consists of rigid, geometrically accurate vertebrae held together with deformable intervertibral disks, facet joints, and ligaments modeled as a series of nonlinear springs. These deformable structures were rigorously tuned, through failure, to mimic existing experimental data; first as functional unit characterizations at three cervical levels and then as a fully assembled c-spine using the experimental data from Duke University and other data in the NHTSA database. After obtaining satisfactory validation of the performance of the assembled ligamentous cervical spine against available experimental data, 22 cervical muscle pairs, representing the majority of the neck's musculature, were added to the model. Hill's muscle model was utilized to generate muscle forces within the assembled cervical model. The muscle activation level was assumed to be the same for all modeled muscles and the degree of activation was set to correctly predict available human volunteer experimental data from NBDL. The validated model is intended for use as a post processor of dummy measurement within the simulated injury monitor (SIMon) concept being developed by NHTSA where measured kinematics and kinetic data obtained from a dummy during a crash test will serve as the boundary conditions to "drive" the finite element model of the neck. The post-processor will then interrogate the model to determine whether any ligament have exceeded its known failure limit. The model will allow a direct assessment of potential injury, its degree and location thus eliminating the need for global correlates such as Nij.

• 대한두경부종양학회지
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• 제16권1호
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• pp.33-36
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• 2000

Objectives: Angiocentric T-cell lymphoma of the head and neck is an angiocentric and angiodestructive lymphoreticular proliferative disorder. It has been treated with various treatment modalities, but its prognosis is poor and the treatment modality is controversial. We performed this study to suggest a treatment modality with improved results. Materials and Methods: We studied 40 cases of pathologically confirmed angiocentric T-cell lymphoma from July 1984 to December 1996, 35 cases of which showed complete response after initial treatment. All the patients were divided into two groups according to treatment modality. 15 cases received radiotherapy alone (Group I) and 20 cases received radiotherapy after five cycles of CHOP-Bleo chemotherapy(Group II). We analyzed the subsites of tumor, stage, treatment modality and treatment outcome and causes of failure for each group, and compared the three-year no evidence of disease(NED) between the two groups. Results: The three-year NED of a combined chemoradiotherapy was higher than that of a radiotherapy alone (p=0.0478). The three-year NED according to groups and stage were as follows: Group I=6/15(40.0%), stage IE=5/10(50.0%), stage IIE=1/5(20%), Group II=13/20(65.0%), stage IE=9/13(69.2%), stage IIE=4/7(57.1%). Radiotherapy alone is not well effective for the nasal cavity lymphoma extended to paranasal sinus and the palate. Conclusion: We are unable to provide clear guidelines for treatment, but recommend the initial treatment with oral alkylating agents and steroids followed by radiotherapy for Ann Arbor stage II tumors and stage I of the palate lymphoma and the nasal cavity lymphoma extended to paranasal sinus.

• Radiation Oncology Journal
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• 제21권2호
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• pp.112-117
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• 2003

목적: 진행된 두경부암을 대상으로 다분할 방사선치료를 시행한 후 실패양상 및 생존율을 분석하고 다분할 방사선치료의 효과를 알아보고자 한다. 대상 및 방법: 1990년 9월부터 1995년 10월 사이에 계명대학교 동산의료원 방사선종양학과에서 진행된 두경부암으로 다분할 방사선치료를 시행한 환자 24명을 대상으로 하였다. 환자의 연령분포는 38세에서 71세로 중앙값 55세이었다. 병기별로 3기 11명, 4기 13명이었으며 남자가 21명이었고 비인두암 6명, 하인두암 6명, 후두암 5명, 구강인두암 3명, 부비동암 3명, 구강암 1명이었다. 방사선치료는 6 MV x-선으로 1일 2회, 최소 6시간 간격으로 분할조사량 1.2 Gy 시행하여 총치료선량은 64.4 Gy에서 76.8 Gy로 평균총방사선량은 72 Gy이었다. 추적관찰기간은 3개월에서 136개월이었고 중간 추적관찰기간은 52개월이었다. 결과: 전체환자의 3년 생존율과 5년 생존율은 각각 66.7$\%$, 52.4$\%$이었고 전체 환자의 3년 무병생존율은 66.7$\%$, 5년 무병생존율은 47.6$\%$이었다. 병기별로 3년, 5년 무병생존율은 3기는 81.8$\%$, 63.6$\%$, 4기는 53.8$\%$, 32.3$\%$이었다. 국소재발이나 원격전이의 소견 없이 생존해 있는 환자가 10명이며 원격전이는 25$\%$, 국소재발은 12.5$\%$로 원격전이가 주된 실패원인이었다. 원격전이인지 국소 재발인지 분명하지 않은 경우가 2명, 다른 원인으로 사망한 경우가 3명이었다. 원격전이 장소는 폐 3명, 뼈 1명, 간 2명이었으며 1명에서 식도에 2차암이 발생하여 사망하였다. 추적관찰 기간 중 1명에서 방사선치료 후 58개월에 하악골괴사로 수술한 경우를 제외하고 중등도 이상의 심각한 만성부작용이 발생한 환자는 없었다. 결론: 대상 환자의 수는 적으나 진행된 병기의 두경부암에서 다분할 방사선치료법이 급성 부작용은 다소 증가하나 만기부작용의 증가 없이 국소 재발의 감소와 무병생존율을 증가시킬 수 있을 것이라고 생각한다.

• 대한두경부종양학회지
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• 제13권2호
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• pp.228-234
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• 1997

Squamous cell carcinoma originating in the parotid gland has rare occurrence. The primary squamous cell carcinoma of the parotid gland comprise about 0.3% and 9.8% of all parotid malignant tumor. We investigated the clinical behavior and treatment outcome of patients with primary squamous cell carcinoma of the parotid gland. We reviewed all cases of possible primary squamous cell carcinoma of the parotid gland treated at Yonsei Cancer Center, Seoul, Korea, from 1981 through 1995. A total of 128 had primary parotid malignancy. Metastatic squamous cell carcinoma and mucoepidermoid carcinoma were excluded in this study. Ten cases of primary squamous cell carcinoma of the parotid gland were identified. 6 cases of them are men & 4 cases are women. The age of patients ranged from 31 to 68 years with median age of 55 years. On physical examination, 5 cases had palpated cervical neck node and 6 cases had facial nerve palsy. Staging was done according to the current guidelines established by the American Joint Committee on Cancer (1992). Two cases were stage I, 1 in stage III, and 7 in stage IV. Six cases were performed operation and postoperative radiation therapy. Four cases were treated by curative radiation therapy, dose of more than 65 Gy on parotid gland region. The 5 year actual survival rate and the 5 year disease free survival rate were 30.8%, and 40.0%. Initial complete response rate was 70% for all patients. Local failure were occurred 3 of 7 patients with local controlled cases, failure sites were primary site, ipsilateral cervical neck node, contralateral supraclavicular node. Most recurrences developed within 1 year of initial treatment. Distant metastasis was appeared 2 of 3 patients who did not achieved local control. Primary squamous cell carcinoma of the parotid gland occured infrequently. A retrospective study at the Yonsei Cancer Center indicates incidence of 7.8%. At diagnosis, advanced stage, neck node presentation, facial nerve paralysis were associated with a poor prognosis. These results may suggested that radical surgical excision may be treatment of choice and that planned postoperative radiotherapy may be bendicial for reducing locoregional recurrence rates.

• 대한두경부종양학회지
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• 제17권2호
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• pp.169-173
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• 2001

Objectives: The p53 tumor suppressor gene encodes a nuclear transcription factor that is critical regulator of cell growth and proliferation through its action in cell-cycle checkpoint control. The wide variety of stressful stmuli which include DNA damage, hypoxia, heat shock, metabolic changes activate the p53 protein, which in turn drives a series of events that culminate either in cell cycle arrest or apoptosis. Mutations of the p53 gene is the most common genetic alteration in human cancer. This gene is altered in approximately 40-60% of head and neck cancers. Whereas the wild-type form of the p53 protein plays a central role in cell-cycle control in response to DNA damage, most of the mutant forms are unable to do so. The high levels of p53 protein expression in tissues are related to the increased cellular proliferative activity and may be associated with the poor clinical outcome. To determine whether the expression of the p53 protein has prognostic significance and is associated with patterns of treatment failure in head and neck squamous cell carcinoma (HNSCC), We analyzed p53 overexpression in 40 cases of HNSCC. Materials and Methods: Immunohistochemical analysis with a monoclonal antibody (DO7) specific for p53 protein was used to detect expression of the protein in formalin-fixed, paraffin-embedded tumor samples from 40 HNSCC. We evaluated p53 protein expression and analyzed the relationship between the p53 overexpression and age, sex, primary tumor site, stage, survival rate, recurrence. All reported P values resulted from two-sided statistical tests. Results: Overexpression of p53 was detected in 20 cases(50%) among 40 cases of HNSCC. The p53 overexpression was not associated with age, sex, primary tumor site, stage, recurrence and survival rate. Conclusions: In our results, p53 was not significant prognostic factor in HNSCC. Based on many previous studies, It is evident that p53 has a certain role in tumorigenesis of HNSCC. So, the further study is needed to evaluate the prognostic significance of p53 in HNSCC.

• Archives of Reconstructive Microsurgery
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• 제5권1호
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• pp.46-55
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• 1996

The purpose of this study is to investigate if there is a higher rate of free flap failure in cases of vein grafts compared to non-vein graft, and to analyze the clinical usefulness and necessity in elective free flap surgery. We have used 24 vein grafts in 208 free flaps from May, 1986 until August, 1995. Vein grafts were from 2cm to 50cm in length between the recipient and donor vessels. Reconstructed sites were 10 lower extremities, 8 head and neck, 4 hand, and 2 trunk. Vein grafts were used 14 for arterial, 6 venous, 4 in both arterial and venous anastomoses. We intentionally used long vein grafts longer than 5cm for improved blood flow in cases of peripheral vascular disease, radionecrotic wounds, lower leg trauma. Short vein grafts of about 3cm in length were used to overcome the shortage of vascular length in cases of unexpected vessel anomaly, short donor vessel, and difficult access to recipient vessels after radical neck dissection. All veins were carefully handled with ligation of very small branches and were transferred to the recipient site without irrigation. 8 flaps were failed out of a total of 208 free flaps, however there was no failure among the 24 cases that needed vein grafts between the donor and recipient vessels. Success rates between non-vein grafts free flaps and vein graft free flaps were 95.6%(8/184) and 100%(0/24). Even though the vein grafts increase the operation time and the number of anastomoses, they do not result in any increased failure rate of free flap surgery(4.4% versus 0%). In addition to the reducing tension between recipient and donor vessels, the surgeon can select better recipient vessels with excellent blood flow so that vein grfats in microsurgery can provide a high success rate of free flaps.

• 대한두경부종양학회지
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• 제19권1호
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• pp.16-20
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• 2003

Objectives: Radiotherapy is an effective treatment in the initial management of T1 glottic carcinoma, but local recurrent or residual tumor growth is found in approximately 10% of the patients. Even in recurrence or residual tumor, in highly selected cases, conservation surgery with preservation of a portion of the larynx is feasible. So we investigated the efficacy of salvage vertical partial laryngectomy for recurrent glottic carcinoma after irradiation. Material and Methods: Retrospectively we reviewed a consecutive series of 10 patients treated by conservative vertical partial laryngectomy of the larynx for radiation-failure, recurrent T1 glottic squamous cell carcinoma treated at Severance Hospital from 1994 to 2002. Results: Local recurrence developed in 4 patients (40%). Two patient was salvaged by further totallaryngectomy. Successful salvage was achieved finally in 8 (80%) of the 10 patients. There was no operative mortality. Postoperative perichondritis was developed in two patients. One was resolved by conservative treatment, but the other has underwent the total laryngectomy. Conclusion: A vertical partial laryngectomy in case of recurrent glottic carcinoma after a course of irridation should be the therapy of choice when stringent criteria are observed.

• 대한후두음성언어의학회지
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• 제20권1호
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• pp.11-16
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• 2009

OPD based laryngeal procedures offers a new avenue to the modern laryngologist, incorporating new technology in the office setting. With the development of flexible fiberoptic endoscopes, compact video system, and short acting anesthetics and sedatives allow these procedures. The success or failure of procedures are depend on excellent topical anesthesia. An inadequately anesthetized patient is apt to be uncomfortable, anxious and hyperresponsive and therefore unlikely to tolerate the procedure. On the other hand, a patient who is well informed, reassured, and thoroughly anesthetized can complete procedures. Therefore, optimal anesthesia is obligatory for excellent surgical results. The phonosurgeon should choose the anesthetic and sedative agents based on duration of action, time of onset of action, and any medical contraindications that the patient may have. And should be familiar with the properties and interaction of the agents used, as well as the signs of toxicity.

• 대한두경부종양학회지
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• 제11권1호
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• pp.30-35
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• 1995

Localized non-Hodgkin's lymphomas of head and neck are generally treated with radiation therapy with or without chemotherapy and the results of treatments are favorable, but the recurrences in the primary site or distant sites are a major contributor to failure, We experiened 19 cases of localized non-Hodgkin's lymphomas for 4-year period and retrogradely analized them. We treated patients with Ann Arbor stage I and low grade histology in Working formulation with radiation therapy and patients with Ann Arbor stage II, moderate to high grade histology or extensive tumor size with combination chemotherapy, The complete responses were occurred in 15 of 19 patients (radiation therapy, 5/6 (83.3%); chemotherapy 10/13(76.9%)). 3 relapses were occurred; 2 were in local relapses and 1 was in distant leptomeningeal relapse and the counter-therapeutic modalities were successful in 2 cases. Our results suggest that Ann Arbor stage is significant prognostic factor and appropriate staging with extensive methods is important to improve the results of treatment.

• 대한두경부종양학회지
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• 제17권2호
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• pp.190-193
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• 2001

Background and Objectives: Reliable and versatile free flap has become a mainstay in reconstruction of the head and neck. But until now pectoralis major myocutaneous flap (PMMCF) as workhorse is useful and has some advantages such as good viability, one-stage reconstruction and carotid protection. The objective of this study was to review the role and indication of PMMCF in this era of potent free flaps for head and neck reconstruction. Patients and Methods: Sixty one PMMCF and one hundred forty six free flaps used for head and neck reconstruction between 1991 and 2001 were reviewed retrospectively. We compared the applied sites of flap, the flap failure rate and complications. Results: Contrary to the free flap, use of PMMCF has gradually decreased after the middle of 1990s. PMMCF were mainly used for mucosal defect(33cases, 54.1%) and cervical skin defect(22cases, 36.1%) and free flap were mainly used for mucosal defect(129cases, 88.4%). In point of use of PMMCF according to years, from 1991 to 1997, 30cases(70%) are used to reconstruct mucosal defect and 12cases(29%) are used to reconstruct skin defect. But from 1998 to 2001, only 2cases(10.5%) are used to reconstruct mucosal defect and 13cases(68.4%) are used to reconstruct neck skin defect. In case of free flap, from 1991 to 1997, 41cases (87%) are used to reconstruct mucosal defect and from 1998 to 2001 88cases(89%) are used as same purpose. Three major necrosis (more than 50%) deveolped in 61 PMMCF (4.9%) and three major necrosis developed in 146 free flaps(2.1%). Conclusion: PMMCF is no longer flap of choice for primary reconstruction but it is a still one of a good tool in some head and neck reconstruction such as covering single wide defect of face or neck skin, back-up procedure of free flap, postoperative status, treatment of pharyngocutaneous fistula and covering vital structure.