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A Study on the Evaluation of Patient Dose in Interventional Radiology (중재적방사선검사에서 환자 피폭선량에 관한 연구)

  • Park, Hyung-Sin;Lim, Cheong-Hwan;Kang, Byung-Sam;You, In-Gyu;Jung, Hong-Ryang
    • Journal of radiological science and technology
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    • v.35 no.4
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    • pp.299-308
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    • 2012
  • To perform patient dose surveys in major interventional radiography procedures as a mean of inter-institutional comparison and of establishing reference dose levels with the ultimate goal of optimizing patient doses in the field of interventional radiography. We reviewed international patient dose survey data in the literature and measured patient dose in major interventional radiography procedures (TACE, AVF, PTBD, TFCA, GDC embolization). ESD(Entrance Skin Dose) was measured using TLD chips attached to the patient skin and ED(Effective Dose) was calculated using angiography unit-derived DAP. A survey of patient dose in interventional radiography procedures were also performed with a questionnaire for interventional radiologists and we proposed a guideline for optimizing patient doses in the field of interventional radiology. The patient dose survey data in interventional radiography procedures were very rare in literature compared with those in diagnostic radiography procedures. In TACE, the mean ED was 25.43 mSv and the mean ESD was 511.75 mGy. The mean ED of TACE was not high, but the cumulative dose should be checked, due to longer procedure TACE. In TFCA, the mean ED was 22.6 mSv and it was relatively high compared with data of other countries. In GDC embolization, the mean ED was not available, because GDC embolization was performed with old Image-Intensifier-type unit and there has no unit-installed ionization chamber. Also, the mean ESD of GDC embolization was up to 2,264 mGy and further studies are needed to calculate the net ED of GDC embolization. Patient dose occurred during interventional radiography procedures are high related with the difficulty of the procedure, fluoroscopy time, the number of angiographies and the treatment protocol. Therefore, continuous education and efforts should be made to optimize the patient dose in the field of interventional radiology.

Incidence Density of Antibody against Hepatitis C Virus in Seoul and Gyeonggi Area; A Retrospective Cohort Study - Based on Medical Screening Data from a General Hospital - (서울 경기지역 성인의 C형 간염 바이러스 항체 양성자 평균발생률; 후향적 코호트 연구 - 일개 병원의 종합검진 자료를 중심으로 -)

  • Ryu, Seung-Ho;Kim, Dong-Il;Suh, Byung-Seong;Kim, Woon-Sool;Chang, Yoo-Soo;Beck, Sung-Ho;Lee, Soo-Jin;Kim, Yong-Kyu;Song, Jae-Chul
    • Journal of Preventive Medicine and Public Health
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    • v.37 no.4
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    • pp.337-344
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    • 2004
  • Objectives : This study was performed to determine the incidence density and the prevalence of sero-positive hepatitis C from 1999 to 2002 among adults aged 20 and over residing in Seoul and the Gyeonggi province. Method : The data for period was obtained from 114,635 adults, residing in Seoul or the Gyeonggi province, who had undertaken comprehensive health screening tests from Jan 1999 to Dec 2002 in a University hospital in Seoul. Among them, subjects with sero-negative status against hepatitis C were selected (21,408 in 1999, 28,830 in 2000) and then followed up until Dec 2002 to determine the incidence of hepatitis C during this period. The serum was tested with the immunoradiometric assay (IRMA) which uses third generation HCV antibody. Age adjusted rates were estimated by direct standardization using a reference population of 2000 aged from 20 to 80 years. Results : The prevalence of anti-HCV from 1999 to 2002 was 2.1 per 1000 persons(95% CI $1.8{\sim}2.4$). Male showed 1.7 per 1000 persons (95% CI $1.4{\sim}2.1$), while female showed 2.7 per 1000 persons(95% CI $2.2{\sim}3.2$). Age?sex adjusted rate showed 2.8 per 1000 persons (95% CI $2.64{\sim}2.96$), which is lower than the results of some previous study. The prevalence showed a significantly increasing pattern with age both in males and females (p<0.05). The incidence density of anti-HCV among the population aged 20 and over was 1.1 per 104 person-years at risk (95% CI $0.6{\sim}2.4$); 1.2 (95% CI $0.6{\sim}2.7$) for males and 0.8 (95% CI $0.6{\sim}4.2$) for females. Age adjusted incidence density was 2.91 per 104 person-years at risk (95% CI $2.43{\sim}3.38$) for those aged 20 and over. It showed an increasing pattern with age (p<0.05), especially for those age over 50 years. Conclusion : The study subjects for this study were supposedly healthier than the general population so the prevalence and incidence for the general population are thought to be higher than the results of the present study.

Morphometric Study on the Arterial Palmar Arch of the Hand (손바닥 동맥활에 관한 형태계측 연구)

  • Park, Bong Kwon;Jang, Soo Won;Choi, Seung Suk;Ahn, Hee Chang
    • Archives of Plastic Surgery
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    • v.36 no.6
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    • pp.691-701
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    • 2009
  • Purpose: Deviations of arterial palmar arches in the hand can be explained on the embryological basis. The purpose of this study was to provide new information about palmar arches through cadaver's dissection. The values of the location and diameter in these vessels were analyzed in order to support anatomical research and clinical correlation in the hand. Methods: The present report is based on an analysis of dissections of fifty - three hands carried out in the laboratory of gross anatomy. A reference line was established on the distal wrist crease to serve as the X coordinate and a perpendicular line drawn through the midpoint between middle and ring fingers, which served as the Y coordinate. The coordinates of the x and y values were measured by a digimatic caliper, and statistically analyzed with Student's t - test. Results: Complete superficial palmar archs were seen in 96.2 % of specimens. In the most common type of males, the superficial arch was formed only by the ulnar artery. In the most common type of females, the superficial arch was formed anastomosis between the radial artery and the ulnar artery. The average length of the superficial and deep palmar arch is $110.3{\pm}33.0mm$ and $67.9{\pm}14.0mm$ respectively. Regarding the superficial palmar arch, ulnar artery starts $-16.1{\pm}5.1mm$ on X - line, and $2.5{\pm}24.5mm$ on Y - line. Radial artery appears on palmar side $7.7{\pm}3.2mm$ on X - line, and $20.9{\pm}10.9mm$ on Y - line. But radial artery starts on $6.3{\pm}3.6mm$ on X - line, and $3.4{\pm}5.1mm$ on Y - line. Digital arteries of superficial palmar arch starts on $6.1{\pm}3.7mm$, $33.9{\pm}8.8mm$ on index finger, $1.8{\pm}3.4mm$, $40.1{\pm}7.3mm$ on middle finger, $-3.2{\pm}4.9mm$, $42.6{\pm}7.0mm$ on ring finger, and $-8.9{\pm}5.1mm$, $42.5{\pm}80mm$ on little finger in respective X and Y coordinates. Radial artery of deep palmar arches measured at the palmar side perforating from the dorsum of hand. It's coordinates were $9.7{\pm}4.8mm$ on X - line, $21.7{\pm}10.2mm$ on Y - line. Ulnar artery was measured at hypothenar area, and it's coordinates were $-20.4{\pm}6.3mm$ on X - line, and $30.6{\pm}7.4mm$ on Y - line. Conclusions: Anatomically superficial palmar arch can be divided into a complete and an incomplete type. Each of them can be subdivided into 4 types. The deep palmar arch is less variable than the superficial palmar arch. We believe these values of the study will be used for the vascular surgery of the hand using the endoscope and robot in the future.

Clinical Usefulness of Arterial Spin Labeling Perfusion MR Imaging in Acute Ischemic Stroke (급성 허혈성 뇌경색 환자에서 동맥스핀표지 관류자기공명영상의 유용성)

  • Oh, Keun-Taek;Jung, Hong-Ryang;Lim, Cheong-Hwan;Cho, Young-Ki;Ha, Bon-Chul;Hong, Doung-Hee
    • Journal of radiological science and technology
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    • v.34 no.4
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    • pp.323-331
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    • 2011
  • We evaluated clinical usefulness of Arterial spin labeling perfusion MR imaging on the acute ischemic cerebral infarction patients through this study. We compared 22 patients who were done with DSC imaging and ASL imaging in admitted emergency room with acute ischemic cerebral infarction, with 36 normal comparison persons (DSC image on 21persons, ASL images on 15persons). Siemens Magnetom Verio 3.0T with 12 channel head coil was used for this study. DSC image obtained 4 maps(rCBV, rCBF, rMTT, TTP) through post-processing. For qualitative analysis we compared the area of lesion macro-diagonal with the size of diffusion weighted MR image for rMTT, TTP, rCBF, rCBV, ASL maps. For Quantitative analysis we analyzed significant correlations between less than 3 cm infarction group and normal comparison group using mean relative value of flowing image with Mann-Whitney U test. TTP(95.5%) and rCBF(95.5%) maps showed high recognition rate in qualitative analysis for >3cm infarction group. The rCBF and rCBV map tests were highly related with final stage stroke areas. Mean relative value of infarction group showed a significant correlations in quantitative analysis(p<0.05). As a conclusion, arterial spin labeling image showed high lesion recognition rate in the >3cm infarction group. Mean relative values in quantitative evaluation were used for reference data. If we do more sustainable researches, ASL image will be useful for an early diagnosis of cerebral infarction, determination of the range of ischemic pneumbra and effective treatments.

The Comparison of DVH between Multiple arc FSRT and Conformal FSRT (Multiple arc FSRT와 Conformal FSRT의 DVH 비교)

  • Kim Ki-Hwan;Kim Jun-Sang;Jang JiYoung;Kim Jae-Sung;Kim Seong-Ho;Song Chang-Joon;Park Min-Kyu;Cho Moon-June
    • Radiation Oncology Journal
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    • v.17 no.3
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    • pp.261-267
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    • 1999
  • Purpose : In FSRT (Fractionated stereotactic radiotherapy) planning, we studied the usefulness between multiple arc FSRT and conformal FSRT by comparing tumor shape and DVH (dose volume histogram). Materials and Methods In Chungnam Univ. hospital, we had treated the sixteen patients with FSRT from Aug. 1997 to Dec. 1998. In choosing multiple arc FSRT or conformal FSRT, we had considered If (irregular factor) after calculating tumor volume and surface area. We had considered multiple arc FSRT if tumor shape was similar to sphere or the value of If was less than 1.25, conformal FSRT if tumor shape was very irregular or If was more than 1.3. For evaluation of treatment planning, we had considered the appropriate DVH for tumor volume and for critical organs. Results : The errors between reference point and the coordinates point on AP, Lat radiography were less than 1 mm before treatment. We had planned $3\~$5 arcs for multiple arc FSRT, $5\~6$ports for conformal FSRT. The mean dose distribution of tumor volume of cumulative DVH between multiple arc FSRT and conformal FSRT was 90.6, 85%, respectively. The dose of critical organs irradiated was less than $5\%$ maximum dose of cumulative DVH. Conclusion : We had obtained the similar value between multiple arc FSRT and conformal FSRT, so that we had appropriate treatment planning of FSRT for multiple arc FSRT and conformal FSRT according to tumor shape and size.

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Functional Assessment of Gangcheon Replacement Wetland Using Modified HGM (수정 수문지형학적 방법을 적용한 강천 대체습지의 기능평가)

  • Kim, Jungwook;Lee, Bo Eun;Kim, Jae Geun;Oh, Seunghyun;Jung, Jaewon;Lee, Myungjin;Kim, Hung Soo
    • Journal of Wetlands Research
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    • v.19 no.3
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    • pp.318-326
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    • 2017
  • Riverine wetlands were reduced and damaged by dredging of rivers and constructing parks in wetlands by Four Rivers Project from 2008 to 2013. Therefore, replacement wetlands were constructed for the compensation of wetland loss by the government. However, It is not enough to manage replacement wetlands. In order to manage the wetlands efficiently, it is necessaty to assess the functions of the wetlands and to manage them according to their functions. Here we performed functional assessments for a replacement wetland called Gangcheon wetland using the modified HGM approach. Hydrological, biogeochemical, animal habitat, and plant habitat functions for the wetland were assessed. To assess the functions, we collected informations for modified HGM approach from the monitored hydrologic data, field survey, published reports and documents for before and after the project, and hydraulic & hydrologic modeling. As the results of the assessment, the hydrological function for the replacement wetland showed 65.5% of the reference wetland, biogeochemical function showed 66.6%, plant habitat function showed 75%, and animal habitat function showed 108.3%. Overall, Gangcheon wetland function after the project was reduced to 78.9% of the function before the project. The decrease in hydrological function is due to the decrease of subsurface storage of water. And the decrease in biogeochemical & pland habitat functions is due to the removal of sandbank around the Gangcheon wetland. To compensate for the reduced function, it is necessary to expand the wetland area and to plant the various vegetation. The modified HGM used in this study can take into account the degree of improvement for replacement wetlands, so it can be used to efficiently manage the replacement wetlands. Also when the wetland is newly constructed, it will be very useful to assess the change of function of the wetland over time.

Soil Salinity and Vegetation Distribution at Four Tidal Reclamation Project Areas (4개 간척 지구에 분포하는 식생과 토양 염류농도)

  • Lee, Seung-Heon;Ji, Kwang-Jae;An, Yeoul;Ro, Hee-Myong
    • Korean Journal of Environmental Agriculture
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    • v.22 no.2
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    • pp.79-86
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    • 2003
  • This research was conducted to present reference data to be used as newly reclaimed tidal land management. We investigated vegetation succession at 4 reclaimed/reclaiming project areas and discussed relationship with soil and vegetation trhrough investigation and analysis soil chemical characteristics at 2 areas. 14 families 58 kinds were investigated. Vegetation were variou at Dea-Ho conservation polt and Seok-Mun National Industrial Area which are maintaining naturally. Vegetation were simple at Hong-Bo and Dongjin and MinKyong river areas which effected sea water. Common species that were investigated at 9 sites were Suaeda asparagoides, Aster tripolium, Phragmites australis, Suaeda maritima, Suaeda japonica, Carex scabrifolis. As soil desalinization progressing, soil classified at first saline-soidc soil, the nest saline soil and then normal soil. Chenopodiaceae revealed at about 30 dS/m of soil ECe and existed to 10 dS/m of soil ECe. At about 20 dS/m of soil ECe. Aster tripolium, Calamagrostis epigeios, and Sonchus brachyotus revealed and then non-halophytes and common plants at inland revealed at low soil ECe of about 10 dS/m. However it was not to progress vegetation sucdession and soil desalinization at the same time, owing to input of seeds or plants ect from out-ecosystem. So for promotion of vegetation at newly reclaimed tidal land, we proposed that it was very effective to plant artificially halophytes or suitable species through soil test.

Carbon Budget Evaluated in Two Urban Parks of Seoul (서울의 두 도시 근린공원에서 평가된 탄소수지)

  • Kim, Gyung Soon;Pi, Jung Hun;An, Ji Hong;Lim, Chi Hong;Jung, Song Hie;Joo, Seung Jin;Lee, Chang Seok
    • Korean Journal of Ecology and Environment
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    • v.49 no.1
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    • pp.51-61
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    • 2016
  • This study was carried out to assess the carbon budget of two urban parks and one natural park and to prepare the plan for improving the ecological functions of the park including carbon sink. Net Ecosystem Production (NEP) of those study sites was calculated from the relationship between Net Primary Production (NPP) and soil respiration of each study site. To understand carbon budget of the whole area designated as the park, carbon budget of the urban park was analyzed by classifying the vegetated and the non-vegetated zones. NEP of the Nohae and the Sanggye parks calculated by reflecting areal size that the non-vegetated zones occupy were shown in -1.0 and $0.6\;ton\;C\;ha^{-1}yr^{-1}$, respectively. On the other hand, NEP of Mt. Bulam natural park as a reference site was in $2.3\;ton\;C\;ha^{-1}yr^{-1}$. Based on the result, the Nohae park was assessed as carbon source rather than carbon sink. On the other hand, the Sanggye park was classified as carbon sink but the role was poor compared with natural park. The result is, first of all, due to lower NPP of the vegetation introduced for the parks compared with natural vegetation. The other reason is due to wide arrangement of non-vegetated zone. To solve those problems and thereby to create the urban park with high ecological quality, selection of plant species suitable for the ecological characteristic of the park, their arrangement imitated natural vegetation, and ecological zoning were recommended.

Legal Aspects on ICAO SARPs Regarding Alternative Fire Extinguishing Agent to Halon Fire Extinguishers

  • Lee, Gun-young;Kang, Woo-Jung
    • The Korean Journal of Air & Space Law and Policy
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    • v.33 no.1
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    • pp.205-226
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    • 2018
  • For sustainable development of air transport, the establishment and application of international standards of environmental protection area is significant. The development and use of alternative fire extinguishing agent to Halon, which is used for the fire extinguishing systems of engine nacelles/APU and cargo compartments, has been requested in order to protect the ozone layer. The ICAO has been active in preparing international standards and recommended practices (SARPs); however, certification of alternative fire extinguishing agents has been postponed due to technical readiness problem.. Consequently, the implementation of SARPs has also been postponed by two years from the end of 2016. to the end of 2018. As such consequences have caused confusion among Member States regarding its implementation, it is necessary to discuss and pay more attention to this issue. ICAO Council and Air Navigation Commission should consider between setting the implementation time frame earlier or giving enough time for mature readiness and preparedness. Also in order to minimize the unnecessary discharge of Halon owned by Member States, it is necessary to consider efficient management methodologies; for example, requesting fire extinguisher manufacturers to recharge in professional ways. For the successful implementation of the SARPs, ICAO developed an implementation task list as including notification of differences, establishment of a national implementation plan, drafting of the modification to the national regulations and means of compliance, adoption of the national regulations and means of compliance. Member States can develop their own rule making process in reference with the ICAO implementation task list. This issue was presented and discussed during the 54th Conference of Directors General of civil aviation, Asia and Pacific Regions which was held in Ulaanbaatar, Mongolia in 2017 with significant attention among participated Contacting States. In this regards, ICAO Council and Air Navigation Commission should consult with Legal Bureau lawyers regarding SARPs preparing process to eliminate difficulties and confusions for proper implementation within effective date.

Pelvic MRI Application to the Dosimetric Analysis in Brachytherapy of Uterine Cervix Carcinoma (자궁경부암의 강내조사치료에 있어서 흠수선량평가시 골반강 자기공명사진의 응용)

  • Chung, Woong-Ki;Nah, Byung-Sik;Ahn, Sung-Ja
    • Radiation Oncology Journal
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    • v.15 no.1
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    • pp.57-64
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    • 1997
  • Purpose : Before we report the results of curative radiotherapy in cervix cancer patients, we review the significance and safety of our dose specification methods in the brachytherapy system to have the insight of the potential Predictive value of doses at specified points. Matersials and Methods : We analyze the 리5 cases of cervix cancer patients treated with intracavitary brachytherapy in the lateral simulation film we draw the isodose curve and observe the absorbed dose rate of point A, the reference point of bladder(SBD) and rectum(SRD). In the sagittal view of Pelvic MRI film we demarcate the tumor volume(TV) and determine whether the prescription dose curve of point A covers the tumor volume adequately by drawing the isodose curve as correctly as possible. Also we estimate the maximum Point dose of bladder(MBD) and rectum(MRD) and calculate the inclusion area where the absorbed dose rate is higher than that of point A in the bladder(HBV) and rectum(HRV), respectively. Results : Of forty-five cases, the isodose curve of point A seems to cover tumor volume optimally in only 24(53%). The optimal tumor coverage seems to be associated not with the stage of the disease but with the tumor volume. There is no statistically significant association between SBD/SRD and MBD/MRD, respectively. SRD has statistically marginally significant association with HRV, while TV has statistically significant association with HBV and HRV. Conclusion : Our current treatment calculation methods seem to have the defect in the aspects of the nonoptimal coverage of the bulky tumor and the inappropriate estimation of bladder dose. We therefore need to modify the applicator geometry to optimize the dose distribution at the position of lower tandem source. Also it appears that the position of the bladder in relation to the applicators needs to be defined individually to define 'hot spots'.

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