Development and Application of a Deep Convolutional Neural Network Noise Reduction Algorithm for Diffusion-weighted Magnetic Resonance Imaging

Dong-Kyoon Han,Kyuseok Kim,Youngjin Lee 한국자기학회 2019 Journal of Magnetics Vol.24 No.2

Diffusion-weighted imaging (DWI) is frequently used in the field of diagnostic medicine to detect various human diseases. In DWI, noise suppression is very important for achieving high detection accuracy of diseases. In this study, we develop a deep convolutional neural network (Deep-CNN) noise reduction algorithm and evaluate its effectiveness in DWI by performing both simulations and real experiments with a 1.5- and a 3.0-T MRI system. The results validate the proposed Deep-CNN algorithm for DWI. Compared with previously developed non-local means (NLM) algorithms, the proposed Deep-CNN algorithm achieves superior quantitative results. In conclusion, the quantitative results verify that the proposed Deep-CNN algorithm has higher noise reduction efficiency and image visibility than previously developed algorithms for DWI.

Feasibility study of cone-beam computed tomography (CBCT) reconstruction algorithm for proton image-guided radiation therapy (IGRT)

Han, Dong-Kyoon,Jo, Byungdu,Lee, Min-Hee,Yoo, Myung Seok,Kim, Kyuseok,Lee, Youngjin Elsevier 2016 OPTIK -STUTTGART- Vol.127 No.20

<P><B>Abstract</B></P> <P>The radiation therapy is most important treatment technique in the field of the oncology. With the improved radiation therapy technologies such as proton image-guided radiation therapy (IGRT), the accuracy of the patient alignment system has been emphasized. The purpose of this study was to validate the possibility of cone-beam computed tomography (CBCT) reconstruction algorithm using X-ray and 3-D proton IGRT by acquiring images sequentially with continuous 360° gantry rotation. To confirm the feasibility of CBCT reconstruction algorithm, we acquired the reconstruction images of the proton IGRT for a mouse and ball phantom, respectively. According to the results, we demonstrated the feasibility of reconstruction algorithm for the proton IGRT. In conclusion, this reconstruction algorithm can help the determination of a treatment target and will be used a main patient alignment system for the proton IGRT. In the future work we need to compare the 180 projection view using X-ray imaging system of the proton therapy with other efficient projection views.</P>

MDCT에서 화질과 방사선량에 관한 연구

한동균(Dong-Kyoon Han),고신관(Shin-Gwan Ko),양한준(Han-Joon Yang),김문찬(Moon-Chan Kim) 대한방사선과학회(구 대한방사선기술학회) 2007 방사선기술과학 Vol.30 No.2

  본 연구는 MDCT장치에 있어 화질평가와 선량평가 방법을 통하여 장치의 항상성을 유지하며 양질의 의료영상을 제공하는 기초자료로 사용함과 더불어, MDCT의 각 장비에 따른 선량을 평가하고 제시하고자 서울소재 14대의 MDCT장치를 대상으로 시행하여 그 기준을 정량화 하였다.<BR>  MDCT를 이용한 화질측정 즉, CT number와 노이즈, 균일도, 공간분해능, 대조도 분해능과 선량 측정 즉, CTDI와 CTDI<SUB>W</SUB>, CTDI<SUB>W</SUB>/100㎃s의 결과는 다음과 같았다.<BR>  CT number는 평균 0.56±0.70HU, 노이즈는 평균 0.39±0.09HU, 균일도는 평균 1.08±0.52HU이었다. 그리고 공간분해능은 평균 0.48±0.05㎜, 대조도 분해능은 평균 3.65±1.16㎜이었다. CTDI는 head phantom을 이용한 경우 중앙부는 평균 43.2±15.4m㏉, 주변부는 45.6±17.5m㏉이었다, 그리고 body phantom에 있어 중앙부 평균은 13.5±4.5m㏉, 주변부는 29.2±10.2m㏉이었다. 주변부가 중앙부에 비해 2.16배 증가되어 나타났다. head phantom을 이용한 경우 CTDI<SUB>W</SUB><SUB></SUB>는 평균 44.8±16.8m㏉, CTDI<SUB>W</SUB>/100㎃s는 평균 18.8±5.3m㏉, body phantom을 이용한 경우 CTDI<SUB>W</SUB>는 평균 24.0±8.3m㏉이고, CTDI<SUB>W</SUB>/100㎃s는 평균 10.1±2.5m㏉이었다.<BR>  위에서 알 수 있듯 MDCT의 CT number와 노이즈, 균일도, 공간분해능, 대조도 분해능과 CTDI와 CTDI<SUB>W</SUB>, CTDI<SUB>W</SUB>/100㎃s는 전체 장치에서 모두 우수하게 나타났다.   The Purpose of this study is to suggest the basic data for making good quality image and maintaining equipment homeostasis by accepting image quality evaluation and radiation dose evaluation in Multi- detector CT. In this study we surveyed 14 CT equipments in Seoul. The results obtained were as follows; CT number was 0.56±0.70HU. Noise was 0.39±0.09HU.<BR>  Uniformity was 1.08±0.52HU. High contrast resolution was 0.48±0.05㎜ and low contrast resolution was 3.65±1.16㎜. For CTDI, the central part and the peripheral part of head phantom were 43.2±15.4m㏉ and 45.6±17.5m㏉, respectively. For body phantom, the central part and the peripheral part of head phantom were 13.5±4.5 and 29.2±10.2m㏉, respectively.<BR>  CTDI<SUB>W</SUB> was 44.8±16.8m㏉ and CTDI<SUB>W</SUB>/100㎃s was 18.8±5.3m㏉ using head phantom. CTDI<SUB>W</SUB> was 24.0±8.3m㏉ and CTDI<SUB>W</SUB>/100㎃s was 10.1±2.5m㏉ using body phantom.<BR>  The refore, CT number, noise, high contrast resolution, low contrast resolution, CTDI, CTDI<SUB>W</SUB> and CTDI<SUB>W</SUB>/100㎃s of MDCT were showed excellently in all equipments.

고정밀도의 단상전파정류형 X선 장치의 제작 및 평가

한동균(Han, Dong-Kyoon),정재은(Jung, Jae-Eun),최준구(Choi, Jun-Gu),성렬훈(Seoun, Youl-Hun),고신관(Ko, Shin-Gwan) 한국산학기술학회 2011 한국산학기술학회논문지 Vol.12 No.1

1950년대 진단용 X선 장치의 국산화가 이루어졌으며, 1960년 초부터 진단용 X선 장치의 수요가 급격히 증 가함에 따라 생산업체의 증가로 의료기기 시장의 많은 발전을 가져왔다. 진단용 X선 장치는 방사선에 대한 인체의 위험 요소인 피폭문제가 있기 때문에 보건복지가족부가 제조, 설치기준을 제정하고 있으며, 이를 기본으로 하여 KS A 4019, KS A 4021, KS A 4022 등에 의해 정밀한 제작이 이루어지고 있다. 진단용 X선 발생장치는 단상 전파 정 류형과 삼상 전파 정류형이 대부분이나, 1980년대 이후 인버터식 X선 발생장치로 대부분 전환되기 시작하였다. 인버 터식 X선 발생장치는 단상 전파정류형 X선 발생장치에 비해 1.5~1.8배의 높은 출력과 단시간 제어가 정확하지만, 가 격이 비싸기 때문에 개인병원에서는 단상전파정류형 X선 장치를 선호하고 있어 단상 전파정류형 X선 장치의 성능개 선이 요구된다. 이에 본 연구자들은 단상 전파정류형 X선 발생장치의 제어장치, 고전압 변압기, 필라멘트 가열변압 기, 정류회로, 고압케이블 등 기기의 구성요소를 제작하고 진단용 X선 발생장치의 성능평가를 시험하였으며, 그 결과 국내 규정인 진단용 방사선 발생장치의 안전관리 규칙에 적합한 기준을 얻을 수 있었다. Diagnosis X-ray equipment localized at 1950's but it is developed suddenly at 1960's with demand together. Manufacture of Diagnostic X-ray equipment is controled by the KS regulation and the Ministry of Health and Welfare because of hazardous element etc. exposure by radiation. Most of diagnostic X-ray equipment ware single phase and three phase full-wave rectification but from 1980's it transforms it was exchanged in inverter type X-ray equipment. Inverter type X-ray equipment produces approximately 50~80% more average photon intensity then single phase full-wave rectification and the accuracy is high. But from a clinic it dose not use because expensive therefor the efficiency improvement of single phase full-wave rectification is necessary. We produced single phase full-wave rectification X-ray equipment control unit, high tension transformer, filament heating transformer, rectification circuit, high tension cable and others and evaluated efficiency, in result which is excellent compare with Rule of Safety Management and KS regulation

소아 방사선 검사 시 안전 안내문이 보호자의 불안감 해소에 미치는 영향

홍기장(Ki-Jang Hong):한동균(Dong-Kyoon Han),김종진(Jong–,Jin Kim),이현국(Hyeon-Kook Lee) 대한영상의학기술학회 2017 대한영상의학기술학회 논문지 Vol.2017 No.1

Purpose:As the national income level increases, frequent diagnostic tests are conducted at the advanced medical level, and radiation exposure during diagnosis may gradually increase. The number of caregivers who are interested in raising children is increasing, and the number of pediatric upper extremity X-ray examinations is increasing every year. However, unfamiliar hospital environments and unclear radiation fears have a psychological negative impact on caregivers. As a health care provider, we should not be overlooked. This is also a stressful event for parents who care for children as well as children. Materials and Methods:From March 2016 to August 2016, 300 guardians of children who had upper- extremity X-ray test(left hand growth plate test) in the department of radiology of Eulji University hospital were included in this study. We directly explained to guardians by suing the pediatric radiation safety manual, made based on the author s previous article Measure and Reduce the exposure dose during examination of child s growth plate using left hand x - ray“ We evaluated efficacy of radiation exposure guidelines for children with upper-extremity X-ray examination (left hand growth plate test) Hospital in the Department of Radiology of Pediatric Radiology. Subject s gender, age, education level, number of children, and annual number of radiological examinations of children were included by general characteristics. The understanding, interest of radiation, and degree of anxiety was measured in the range of 1 to 10. Result:The mean level of understanding of radiation was 4.94 on the 10 point scale, The average degree of concern for radiation is 8.09. Compared to comprehension, interest was high. Of the four groups, the second group had the lowest level of understanding of radiation and the group with the highest level of interest. The pre - stress intensity was the highest at 6.91 and the post - stress intensity was the lowest at 1.22. The mean score of the psychological anxiety score in the pre - evaluation was 7.07 and the psychological anxiety score in the post - evaluation was 1.41. The psychological anxiety was largely resolved. Conclusion:When discussing using the Pediatric Radiation Safety Guidelines, anxiety scores were statistically significantly lower in health care services. This is the result of environmental improvements that are effective in reducing parental anxiety. The higher the satisfaction, the higher the loyalty and the more likely you will return to the hospital. Patient loyalty is therefore important to attract more patients to the hospital and this study is considered effective in increasing patient satisfaction. 목 적:본 연구는 대전의 일개 병원 영상의학과에서 선량의 측정치와 방사선에 대한 안내를 기재한 방사선 안내문을 자체 제작하여 소아방사선 촬영 시 보호자가 갖게 되는 불안감을 해소하고자 하였다. 의료 서비스로서 검사 전 소아 방사선 안전에 대해 면접 설명하고 이 활동의 유무에 따른 소아의 보호자의 방사선에 대한 막연한 두려움의 심리변화와 유용성을 설문 조사하여 보호자의 심리적 변화에 소아 방사선 안전 안내문 면접설명이 어떠한 영향을 주는가에 관한 서비스만족 지향의 효과를 검증하고자 한다. 대상 및 방법: 1) 평가대상 : 본 연구의 대상자는 대전광역시 서구에 위치한 E대학교 병원(이하 병원)의 영상의학과에 소아 성장 판검사(소아 상지 왼손 X-ray검사)를 위해 내원한 소아(만 5세∼13세)의 보호자 300명으로 의사소통이 가능하고 국문 해독이 가능한 보호자. 2) 평가기간 : 2016년 3월 1일부터 2016년 8월31일 까지 6개월. 3) 평가도구 : 방사선 안전 안내문과 설문지를 통한 만족도 조사. 4) 자료수집방법 : 설문지를 통한 스트레스 강도측정 및 안전 안내문의 면접설명을 통한 사전, 사후 만족도 조사. 5) 분석방법 : 설문 내용을 갖고 SPSS Vs18.0 (SPSS, Chicago, USA)을 사용하여 모집단 (소아의 보호자)의 일반적 특성과 소아 방사선에 대한 이해도와 관심도의 빈도분석과 면접설명 유무에 따른 스트레스 강도가 어느 정도 차이를 보이는지 교차 분석하여 비교하였다. 결 과:소아의 보호자인 모집단의 인구학적인 특성을 분석하였고 소아 방사선에 대한 이해도와 관심도를 빈도 분석하였다. 면접설명 유무에 따른 스트레스 강도가 어느 정도 차이를 보이는지 알 수 있었으며 그 효과에 대해 검증할 수 있었다. 결 론:보호자의 방사선에 대한 두려움과 보호자의 문의 및 민원을 해소할 수 있었고 영상의학과의 긍정적 이미지 고취 시킬 수 있었다. 차 후 안전 안내문의 형태적 측면으로 미디어 매체와 같이 시청각 자료를 통한 접근 또는 보호자의 인구학적 특성을 고려한 개발된 도구의 활용은 그 효과를 더욱 증폭시킬 수 있으리라 사료된다.

Enhanced anticancer effects of a methylation inhibitor by inhibiting a novel DNMT1 target, CEP 131, in cervical cancer

( Dong Hyun Kim ),( Hye-min Kim ),( Pham Thi Thu Huong ),( Ho-jin Han ),( Joonsung Hwang ),( Hyunjoo Cha-molstad ),( Kyung Ho Lee ),( In-ja Ryoo ),( Kyoon Eon Kim ),( Yang Hoon Huh ),( Jong Seog Ahn ) 생화학분자생물학회(구 한국생화학분자생물학회) 2019 BMB Reports Vol.52 No.5

Methylation is a primary epigenetic mechanism regulating gene expression. 5-aza-2’-deoxycytidine is an FDA-approved drug prescribed for treatment of cancer by inhibiting DNA-Methyl-Transferase 1 (DNMT1). Results of this study suggest that prolonged treatment with 5-aza-2’-deoxycytidine could induce centrosome abnormalities in cancer cells and that CEP131, a centrosome protein, is regulated by DNMT1. Interestingly, cancer cell growth was attenuated in vitro and in vivo by inhibiting the expression of Cep131. Finally, Cep131-deficient cells were more sensitive to treatment with DNMT1 inhibitors. These findings suggest that Cep131 is a potential novel anti-cancer target. Agents that can inhibit this protein may be useful alone or in combination with DNMT1 inhibitors to treat cancer. [BMB Reports 2019; 52(5): 342-347]

NIgA 신병증을 동반한 자가면역성 간염과 원발성 담관성 간경변증의 Overlap Syndrome 1 예

한동수,이명호,장세진,조균석,기춘석,전용철,박문향,김호중,노우균,손주현 대한소화기학회 1999 대한소화기학회지 Vol.32 No.6

The case in which patients present clinical, biological, and histological features of both primary biliary cirrhosis (PBC) and autoimmune hepatitis (AIH) is rare. Such overlap syndrome is believed to be associated with a poor prognosis. We report a case of PBC-AIH overlap syndrome associated with IgA nephropathy. The patient showed hepatitic and nephritic features including easy fatigability, pruritus, icteric sclera and gross hematuria. The liver biopsy showed chronic hepatitis with piecemea necrosis and bridging necrosis. The clinical data of high titers of antinuclear antibodies and antimi tochondrial antibodies, elevated serum IgM and recurrent pruritus, suggest mixed features of AIH and PBC. IgA nephropathy was confirmed by renal biopsy. High dose of corticosteroids was effective initially, but clinical symptoms were relapsed after tapering the administration of corticosteroids. Thus, azathioprine was administered at a dose of 2 mg/kg/day. A dramatic improvement was noted in clinical conditions and liver tests.

Pharmacokinetics of a sustained-release bovine somatotropin in lactating cows

Han, Seong-kyu,Park, Jin-bong,Kim, Doo,Park, Sang-kyoon,Lee, Ho-sung,Kim, Seong-nam,Chang, Byoung-sun,Ryu, Pan-dong The Korean Society of Veterinary Science 1999 大韓獸醫學會誌 Vol.39 No.2

Bovine somatotropin is known to improve the growth rate and lactation in cattle. In this study, we examined the concentration-time profiles of a sustained-release formulation of bovine somatotropin (BST) and insulin-like growth factor-1 (IGF-1) in plasma and milk in cows. In addition, the possible effect of co-administrated vitamin ADE complex on the pharmacokinetic parameters of BST and IGF-1 was evaluated. 1. Plasma BST and IGF-1 levels reached the peak at 12~24 and 48 hours after the administration of BST, and plasma half-lives ranged 100 to 137 and 201 to 310 hours, respectively. To 8th day after administration, BST and IGF-1 levels in milk were not significantly different from the control levels. 2. Plasma BST levels showed cyclic pattern with high concentrations in early stage after each injection and following gradual declining during repeated administrations at 2 week intervals, while plasma IGF-1 levels in treated animals did not show such a cyclic pattern, but remained higher than the control levels. 3. Milk BST and IGF-1 levels during repeated treatments were not significantly different from the control levels. 4. Co-administration of vitamin ADE complex yielded slightly increased AUC of plasma BST for high dose group, but such effect was not evident in the IGF-1 levels. Co-administration of ADE complex tended to increase plasma BST levels and decrease the elimination half-life of IGF-1. 5. These results suggest that the BST formulation tested is one of the ideal sustained-release formulation for long term use in dairy industry. As for the co-administration of vitamin ADE complex, the benefit of co-administration with BST is needed to be further evaluated.

혈액투석환자에서 합병된 혈색소증 2 예

한대석,함영환,최수임,전재윤,박찬일,김형길,이호영,정동균,정석호 대한내과학회 1989 대한내과학회지 Vol.36 No.3

Iron overload from repeated blood transfusions and administration of iron agents in long term hemodialysis patients is a problem of increasing clinical significance, because eventually it can lead to secondary hemosiderosis and hemochromatosis. So it is important to diagnose iron overload early and restrict blood transfusions and administration of iron agents in these patients. Recently, we experienced two cases of hemochromatosis in long term hemodialysis, confirmed by serum ferritin level, bone marrow study and liver biopsy. One patient had received 110 pints of RBCs for 4 years, and the other patient received 120 pints of RBCs for 5 years. HLA typing was also studied and compared with hemochromatosis alleles (HA), HLA A3, B7, and B14. Treatment with desferrioxamine was started just after discharge, and we observed a reduction in the frequency of blood transfusions. We report these two cases with a brief review of the literature.

Survival Benefit of Neoadjuvant Trastuzumab in HER-2 Positive Breast Cancer

Min Kyoon Kim(김민규),Wonshik Han,Hyeong-Gon Moon,Jisun Kim,Jun Woo Lee,Dong-Young Noh 대한종양외과학회 2013 대한임상종양학회 학술대회지 Vol.2013 No.3