• Journal of The Korean Radiological Technologist Association
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• v.29 no.1
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• pp.221-221
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• 2003

• Journal of Gastric Cancer
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• v.9 no.1
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• pp.10-13
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• 2009

The prognosis of gastric cancer with hepatic metastasis is very poor, even though several treatment modalities exist, such as surgical resection. Indeed, a standard therapy has not been established in such patients. Recently, attempts were made to treat hepatic metastasis of gastric cancer with radiofrequency (RF), which was originally used in primary or metastatic liver cancer. RF has been reported to show similar survival compared to surgical resection and is emerging as a new treatment modality even though it is still not conclusive with respect to efficacy and safety due to the paucity of reports. A prospective study is warranted to evaluate the efficacy of RF in the treatment of gastric cancer with hepatic metastasis compared with conventional modalities.

• Journal of radiological science and technology
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• v.38 no.2
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• pp.155-161
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• 2015

This study confirmed the correlation between the change of the cooling water in internal cooling system and the size of the ablation site of bovine liver in RF heat treatment equipment. The bovine liver was resection with $4{\times}4{\times}4cm^3$ in 2cm cool-tip and with $6{\times}6{\times}6cm^3$ in 3cm cool-tip for the experiments. Area and perimeter of the ablation site for bovine liver were measured by Freehand techniques of MRI. It showed area and perimeter decreased during cool-tip temperature rises 6 and 12 minutes ablation using a 2cm and 3cm cool-tip. The correlation of cool-tip temperature and area and perimeter was statistically significant the result are shown(p=.000). The measurements of area and perimeter were more accurate with MRI in actual measurements and MRI for ablation range. The statistical results using Paired sample T-test was also significant(p=.038). The ablation range of bovine liver decreased according as cooling water temperature increases in RF heat treatment equipment for reason of carbonization occurred due to does not accurately pass the RF energy. Therefore, it is considered the effect of RF heat treatment would be increased if the temperature of the cooling water consistently maintain the low temperature in order to reduce the generation of carbide at RF heat treatment and RF energy is delivered accurately.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.289-289
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• 2010

정상 세포로부터 암과 같은 종양세포를 제거하는 방법으로 암세포가 사멸되는 임계온도 보다 높게 악성조직에 열을 가하는 방법이 연구되어지고 있다 [1]. 전류가 흐를 수 있는 4개의 전기탐침을 종양조직에 삽입하여 국부적으로 열을 발생시키는 발열요법으로 암을 치료하는 연구가 고려되고 있다. 발열요법은 1960년대에 시작하여 우리나라에서는 1985년 연세 암센터에서 capacitive type의 RF heating 또는 전자파에 의한 국소가온법과 방사선치료와 병용으로 이용되고 있다. 주로 이용되는 방법은 Radio frequency heating, Microwave heating, ultrasound heating을 들수 있다. 라디오주파수는 보통 300 MHz 이하의 주파수를 가리킨다. 본 연구에서는 교류파 대신에 직류전원에 의해 열을 발생하는 경우에 관한 연구이다. 전극에 의해 형성되는 전기장에 대한 방정식은 전도매질에서의 DC 응용모드이고, 조직 내에서의 직류 전류에 의해 발생되는 온도 분포를 모델링하는 bioheat 방정식과 연계된 문제이다. 전기장에 의해 발생되는 열의 근원은 resistive heat 또는 Joule 열이다. 본 연구에서는 교류 전류에 의한 RF heating 대신 단순한 모델의 경우로 직류 전류에 의한 열 발생에 관한 이론적 연구를 수행하였다. 종양 조직 내에 삽입된 전극에 22V를 인가하면 60초 이내에 $80^{\circ}C$까지 급속히 증가 된 후, 서서히 $90^{\circ}C$에 까지 도달한다. 4 개의 전극에 대칭적인 전위가 인가 된 경우 $50^{\circ}C$ 이상의 온도 분포를 암 조직의 모양과 유사하게 분포하게 하여 효과적인 치료를 수행 할 수 있는 조건을 제시한다.

• 대한방사선치료학회:학술대회논문집
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• 2000.04a
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• pp.6-6
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• 2000

• 대한방사선치료학회:학술대회논문집
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• 1998.06a
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• pp.14-15
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• 1998

• Journal of Chest Surgery
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• v.43 no.6
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• pp.635-641
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• 2010

Background: Radiofrequency endovenous ablation of incompetent saphenous vein has gaining popularity over the conventional ligation and stripping as a minimally invasive technique. The latest version of radiofrequency endovenous catheter, $VNUS^{\circledR}Colosure$ fast VNUS medical Technologies, San Jose, CA, adopted a segmental ablation system, instead of continous pullback, is designed to reduce treatment time in comparison with the previous model $VNUS^{\circledR}Colosure$ plus VNUS medical Technologies, San Jose, CA. The purpose of this study is to compare the difference between two endovenous radiofrequency ablation systems in terms of treatment efficacy and complication rates. We analyze the initial efficacy and complication rates of $VNUS^{\circledR}Colosure$ fast with $VNUS^{\circledR}Colosure$ plus. Material and Method: Between June 2006 and August 2009, $VNUS^{\circledR}Colosure$ plus was performed to treat varicose vein on 59 limbs in 41. patients and $VNUS^{\circledR}Colosure$ fast was performed on 76 limbs in 67 patients. We retrospectively compared in both group with sex, mean treatment time, mean treatment diameter, conjugated treatment, and complications after the procedure. Result: All patient were symptomatic and diagnosed as varicose vein and underwent level 2 clinical classification with color duplex scan. The mean treatment time for the great saphenous vein was significantly less with $VNUS^{\circledR}Colosure$ fast ($17.0{\pm}6.5min$) than $VNUS^{\circledR}Colosure$ plus ($62.7{\pm}9.8min$). There was no significant difference in 1 yr closure rate between groups (p=0.32). Minor complications such as skin burn, thrombophlebitis, ecchymosis, hematoma, cellulitis, tenderness, and there were not different between the groups. Conclusion: Both $VNUS^{\circledR}Colosure$ fast and $VNUS^{\circledR}Colosure$ plus are effective methods of endovenous saphenous ablation. $VNUS^{\circledR}Colosure$ fast is superior to the previous model with less treatment time preserving compatible efficacy and complications. The efficacy of $VNUS^{\circledR}Colosure$ fast for long term closure rate remains to be established.

• The Journal of Korean Society for Radiation Therapy
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• v.12 no.1
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• pp.1-7
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• 2000

• The Journal of the Korean bone and joint tumor society
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• v.9 no.1
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• pp.84-92
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• 2003

Purpose: To report two cases of bone tumors other than osteoid osteoma in the proximal femur and treated with percutaneous high frequency radioablation method. Cases: We reviewed two cases with intracortical chondroma and enchondroma in the femoral head retrospectively. The patient with intracortical chondroma was a thirty one year old woman and had suffered right hip pain of 1 year duration. The lesion was located in the head of right femur and treated with CT guided percutaneous high frequency radioablation after needle biopsy under general anesthesia. The symptom was gone immediately after the procedure and was discharged postop. 1 day. 15 months has passed without symptom recurrence. Second case having enchondroma, was 56 year old woman complaining of gluteal area pain for 3 months. Radiologic evaluation showed osteolytic lesion with sclerotic rim on the inferior portion of the left femoral head. She received a same therapy with CT guided radiofrequency ablation following needle biopsy. She reported dramatic pain relief after the procedure and was discharged postop. 1 day. No symptom has occurred for 3 months until now. Conclusion: We present 2 cases of bone tumor occurred in the hip joint area other than osteoid osteoma which were treated with CT guided radiofrequency ablation.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.5
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• pp.35-42
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• 2014

Thermal analysis properties and adhesive properties of self-healing agents were evaluated through differential scanning calorimetry, reaction heat measurement, and adhesive shear test. D1E0, D3E1, D1E1, D1E3, and D0E1, depending on the mixing ratio of DCPD and ENB, were considered as self-healing agents. The amount of Grubbs' catalyst, depending on the type of self-healing agents, was varied from 0.1 wt% to 1.5 wt%. In the case of DCPD, the polymerization reaction occurred faster and the stabilized adhesive strength increased as the amount of catalyst increased; however, a large amount of catalyst was required. ENB had excellent reactivity with a small amount of the catalyst; however, high reaction heat was observed at the early stage of polymerization. Thermal analysis properties and adhesive properties of self-healing agents can be controlled by varying a mixing ratio of DCPD and ENB. Among the self-healing agents used for this study, the D3E1 would be one of the most preferable candidates with regard to maximum adhesive strength, reaching time to maximum adhesive strength, stabilized adhesive strength, and reaction heat.