Feasibility of normal tissue dose reduction in radiotherapy using low strength magnetic field

Nuri Hyun Jung,Youngseob Shin,In-Hye Jung,Jungwon Kwak 대한방사선종양학회 2015 Radiation Oncology Journal Vol.33 No.3

Purpose: Toxicity of mucosa is one of the major concerns of radiotherapy (RT), when a target tumor is located near a mucosal lined organ. Energy of photon RT is transferred primarily by secondary electrons. If these secondary electrons could be removed in an internal cavity of mucosal lined organ, the mucosa will be spared without compromising the target tumor dose. The purpose of this study was to present a RT dose reduction in near target inner-surface (NTIS) of internal cavity, using Lorentz force of magnetic field. Materials and Methods: Tissue equivalent phantoms, composed with a cylinder shaped internal cavity, and adjacent a target tumor part, were developed. The phantoms were irradiated using 6 MV photon beam, with or without 0.3 T of perpendicular magnetic field. Two experimental models were developed: single beam model (SBM) to analyze central axis dose distributions and multiple beam model (MBM) to simulate a clinical case of prostate cancer with rectum. RT dose of NTIS of internal cavity and target tumor area (TTA) were measured. Results: With magnetic field applied, bending effect of dose distribution was visualized. The depth dose distribution of SBM showed 28.1% dose reduction of NTIS and little difference in dose of TTA with magnetic field. In MBM, cross-sectional dose of NTIS was reduced by 33.1% with magnetic field, while TTA dose were the same, irrespective of magnetic field. Conclusion: RT dose of mucosal lined organ, located near treatment target, could be modulated by perpendicular magnetic field.

Clinical outcome of fiducial-less CyberKnife radiosurgery for stage I non-small cell lung cancer

Jung, In-Hye,Song, Si Yeol,Jung, Jinhong,Cho, Byungchul,Kwak, Jungwon,Je, Hyoung Uk,Choi, Wonsik,Jung, Nuri Hyun,Kim, Su Ssan,Choi, Eun Kyung The Korean Society for Radiation Oncology 2015 Radiation Oncology Journal Vol.33 No.2

Purpose: To evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS). Materials and Methods: From June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21. Results: The median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48-60 Gy in 3-4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression. Conclusion: The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.

Feasibility of normal tissue dose reduction in radiotherapy using low strength magnetic field

Jung, Nuri Hyun,Shin, Youngseob,Jung, In-Hye,Kwak, Jungwon The Korean Society for Radiation Oncology 2015 Radiation Oncology Journal Vol.33 No.3

Purpose: Toxicity of mucosa is one of the major concerns of radiotherapy (RT), when a target tumor is located near a mucosal lined organ. Energy of photon RT is transferred primarily by secondary electrons. If these secondary electrons could be removed in an internal cavity of mucosal lined organ, the mucosa will be spared without compromising the target tumor dose. The purpose of this study was to present a RT dose reduction in near target inner-surface (NTIS) of internal cavity, using Lorentz force of magnetic field. Materials and Methods: Tissue equivalent phantoms, composed with a cylinder shaped internal cavity, and adjacent a target tumor part, were developed. The phantoms were irradiated using 6 MV photon beam, with or without 0.3 T of perpendicular magnetic field. Two experimental models were developed: single beam model (SBM) to analyze central axis dose distributions and multiple beam model (MBM) to simulate a clinical case of prostate cancer with rectum. RT dose of NTIS of internal cavity and target tumor area (TTA) were measured. Results: With magnetic field applied, bending effect of dose distribution was visualized. The depth dose distribution of SBM showed 28.1% dose reduction of NTIS and little difference in dose of TTA with magnetic field. In MBM, cross-sectional dose of NTIS was reduced by 33.1% with magnetic field, while TTA dose were the same, irrespective of magnetic field. Conclusion: RT dose of mucosal lined organ, located near treatment target, could be modulated by perpendicular magnetic field.

Clinical outcome of fiducial-less CyberKnife radiosurgery for stage I non-small cell lung cancer

In-Hye Jung,MD,MB,Si Yeol Song,MD,PhD,Jinhong Jung,MD,PhD,Byungchul Cho,PhD,Jungwon Kwak,PhD,Hyoung Uk Je,MD,PhD,Wonsik Choi,MD,PhD,Nuri Hyun Jung,MD,MS,Su Ssan Kim,MD,PhD,Eun Kyung Choi,MD,PhD 대한방사선종양학회 2015 Radiation Oncology Journal Vol.33 No.2

Purpose: To evaluate the treatment results in early stage non-small cell lung cancer patients who have undergone fiducial-less CyberKnife radiosurgery (CKRS). Materials and Methods: From June 2011 to November 2013, 58 patients underwent CKRS at Asan Medical Center for stage I lung cancer. After excluding 14 patients, we retrospectively reviewed the records of the remaining 44 patients. All analyses were performed using SPSS ver. 21. Results: The median age at diagnosis was 75 years. Most patients had inoperable primary lung cancer with a poor pulmonary function test with comorbidity or old age. The clinical stage was IA in 30 patients (68.2%), IB in 14 (31.8%). The mean tumor size was 2.6 cm (range, 1.2 to 4.8 cm), and the tumor was smaller than 2 cm in 12 patients (27.3%). The radiation dose given was 48−60 Gy in 3−4 fractions. In a median follow-up of 23.1 months, local recurrence occurred in three patients (2-year local recurrence-free survival rate, 90.4%) and distant metastasis occurred in 13 patients. All patients tolerated the radiosurgery well, only two patients developing grade 3 dyspnea. The most common complications were radiation-induced fibrosis and pneumonitis. Eight patients died due to cancer progression. Conclusion: The results showed that fiducial-less CKRS shows comparable local tumor control and survival rates to those of LINAC-based SABR or CKRS with a fiducial marker. Thus, fiducial-less CKRS using Xsight lung tracking system can be effectively and safely performed for patients with medically inoperable stage I non-small cell lung cancer without any risk of procedure-related complication.

Ventilator support in the pretransplant period predisposes early graft failure after deceased donor liver transplantation

Nuri Lee,Sora Cha,Jongman Kim,Yunmi Lee,Enjin Kang,Hyun Jung Kim,Seung Hui Hong,Jinsoo Rhu,Gyu-Seong Choi,Jae-Won Joh 대한외과학회 2023 Annals of Surgical Treatment and Research(ASRT) Vol.105 No.3

Increased Detection of Colorectal Polyps in Screening Colonoscopy Using High Definition i-SCAN Compared with Standard White Light

Woo Jung Kim,Sang Young Park,Iksoo Park,Wook Jin Lee,Jaechan Park,Nuri Chon,Tak Geun Oh,Kwang Hyun Kim 대한소화기내시경학회 2016 Clinical Endoscopy Vol.49 No.1

Background/Aims: The aim of this study was to evaluate the efficacy of high definition (HD) i-SCAN for colorectal polyp detection in screening colonoscopy. Methods: We retrospectively analyzed the records of 501 patients who had undergone screening colonoscopy performed by three endoscopists with either HD i-SCAN (n=149) or standard white light (n=352) from January 2, 2014 through June 30, 2014. Patient information and inter-endoscopist variation as well as polyp number, endoscopic findings, and pathologic characteristics were reviewed. Results: The detection rates of colorectal and neoplastic polyps were significantly higher using HD i-SCAN than standard white light colonoscopy (52% vs. 38.1%, p=0.004 for colorectal polyps; and 37.2% vs. 27.9%, p=0.041 for neoplastic polyps). Analysis of endoscopic findings revealed no difference in detected polyp size between HD i-SCAN and standard white light colonoscopy (4.59±2.35 mm vs. 4.82±2.81 mm, p=0.739), but non-protruding polyps were more commonly detected by i-SCAN than by standard white light colonoscopy (24.6% vs. 13.5%, p=0.007). Conclusions: Colonoscopy using HD i-SCAN had a significantly higher detection rate of colorectal polyps, including neoplastic polyps, because of improved sensitivity for detecting non-protruding lesions.

시비와 온도 조건에 따른 논 토양 효소 활성도와 미생물 생체 탄소량 변화

백누리(Nuri Baek),박현진(Hyun-Jin Park),곽진협(Jin-Hyeob Kwak),김한용(Han-Yong Kim),최우정(Woo-Jung Choi) 한국토양비료학회 2023 한국토양비료학회 학술발표회 초록집 Vol.2023 No.10

논 양분과 물 관리에 따른 메탄 배출량 변화

백누리(Nuri Baek),박현진(Hyun-Jin Park),Pia Husna Israt,최우정(Woo-Jung Choi) 한국토양비료학회 2022 한국토양비료학회 학술발표회 초록집 Vol.2022 No.10

우리나라 논에서 유기물 투입, 규산질 비료 시용, 논물관리에 따른 메탄 배출량 변화

백누리 ( Nuri Baek ),박현진 ( Hyun-jin Park ),( Pia Husna Israt ),최우정 ( Woo-jung Choi ) 한국농공학회 2022 한국농공학회 학술대회초록집 Vol.2022 No.-

메탄(CH₄)은 2019년 기준 우리나라 농축산업분야 온실가스 배출량의 50% 이상을 차지하고 있으며, 그 중 50% 정도가 담수 조건인 논 생태계에서 배출된다. 담수 상태인 논에서 CH₄은 유기물 분해에 따라 산화환원전위(Eh)가 감소하여 생성되기 때문에 토양이 호기적 상태를 유지하거나, 담수 조건에서도 유기물 분해에서 발생하는 전자(e-) 수용체가 있으면 CH₄ 발생이 감소한다. 따라서, 우리나라에서도 유기물 투입량, 논물관리, 그리고 전자수용체 유효도에 따른 CH₄ 발생량 평가 연구가 활발하게 진행되어오고 있다. 본 연구에서는 문헌조사를 통해 이와 같은 영농관리(유기물 투입, 물관리, 규산질 비료 시용)에 따른 CH₄ 배출량 변화를 종합적으로 평가하였다. 유기물 투입에 의해 CH₄ 발생량은 평균 250% 증가하였으며, 유기물 투입량과 CH₄ 발생량 사이에 정의 상관관계가 있었다. 관행 담수조건과 비교하여 간단관개나 논물얕게 대기 등 물관리에 의해 CH₄ 발생량이 평균 76% 감소하였다. 규산질 비료 투입에 의해 CH₄ 발생량이 감소하였지만, 그 정도는 13%로 물관리보다는 효과가 낮았으며, 규산질 비료 투입량 5톤 ha^-1까지는 CH₄ 발생량이 직선적으로 감소하였지만, 그 이후에는 완만하게 감소하였다. 유기물이 투입된 조건에서 논 물관리에 의해 CH₄ 발생량 저감 효과는 43%로 낮아졌다. 하지만, 유기물이 투입된 조건에서 규산질 비료 시용에 의해 CH₄ 발생량이 93% 증가하였다. 본 연구 결과는 논물관리와 규산질 비료의 CH₄ 발생량 저감 효과는 유기물 투입 여부에 따라 달라짐을 보여준다. 따라서, 향후 토양 유기물 수준이 다양한 조건에서 논물관리와 규산질 비료의 CH₄ 발생량 저감효과에 대한 연구가 필요하다.

우리나라 논에서 유기물 투입, 규산질 비료 시용, 논물관리에 따른 메탄 배출량 변화

백누리 ( Nuri Baek ),박현진 ( Hyun-jin Park ),( Pia Husna Israt ),최우정 ( Woo-jung Choi ) 한국농공학회 2022 한국농공학회 학술대회초록집 Vol.2022 No.-

메탄(CH₄)은 2019년 기준 우리나라 농축산업분야 온실가스 배출량의 50% 이상을 차지하고 있으며, 그 중 50% 정도가 담수 조건인 논 생태계에서 배출된다. 담수 상태인 논에서 CH₄은 유기물 분해에 따라 산화환원전위(Eh)가 감소하여 생성되기 때문에 토양이 호기적 상태를 유지하거나, 담수 조건에서도 유기물 분해에서 발생하는 전자(e-) 수용체가 있으면 CH₄ 발생이 감소한다. 따라서, 우리나라에서도 유기물 투입량, 논물관리, 그리고 전자수용체 유효도에 따른 CH₄ 발생량 평가 연구가 활발하게 진행되어오고 있다. 본 연구에서는 문헌조사를 통해 이와 같은 영농관리(유기물 투입, 물관리, 규산질 비료 시용)에 따른 CH₄ 배출량 변화를 종합적으로 평가하였다. 유기물 투입에 의해 CH₄ 발생량은 평균 250% 증가하였으며, 유기물 투입량과 CH₄ 발생량 사이에 정의 상관관계가 있었다. 관행 담수조건과 비교하여 간단관개나 논물얕게 대기 등 물관리에 의해 CH₄ 발생량이 평균 76% 감소하였다. 규산질 비료 투입에 의해 CH₄ 발생량이 감소하였지만, 그 정도는 13%로 물관리보다는 효과가 낮았으며, 규산질 비료 투입량 5톤 ha^-1까지는 CH₄ 발생량이 직선적으로 감소하였지만, 그 이후에는 완만하게 감소하였다. 유기물이 투입된 조건에서 논 물관리에 의해 CH₄ 발생량 저감 효과는 43%로 낮아졌다. 하지만, 유기물이 투입된 조건에서 규산질 비료 시용에 의해 CH₄ 발생량이 93% 증가하였다. 본 연구 결과는 논물관리와 규산질 비료의 CH₄ 발생량 저감 효과는 유기물 투입 여부에 따라 달라짐을 보여준다. 따라서, 향후 토양 유기물 수준이 다양한 조건에서 논물관리와 규산질 비료의 CH₄ 발생량 저감효과에 대한 연구가 필요하다.