• Title/Summary/Keyword: 영상질

Search Result 1,304, Processing Time 0.031 seconds

The Effect of Partially Used High Energy Photon on Intensity-modulated Radiation Therapy Plan for Head and Neck Cancer (두경부암 세기변조방사선치료 계획 시 부분적 고에너지 광자선 사용에 따른 치료계획 평가)

  • Chang, Nam Joon;Seok, Jin Yong;Won, Hui Su;Hong, Joo Wan;Choi, Ji Hun;Park, Jin Hong
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.25 no.1
    • /
    • pp.1-8
    • /
    • 2013
  • Purpose: A selection of proper energy in treatment planning is very important because of having different dose distribution in body as photon energy. In generally, the low energy photon has been used in intensity-modulated radiation therapy (IMRT) for head and neck (H&N) cancer. The aim of this study was to evaluate the effect of partially used high energy photon at posterior oblique fields on IMRT plan for H&N cancer. Materials and Methods: The study was carried out on 10 patients (nasopharyngeal cancer 5, tonsilar cancer 5) treated with IMRT in Seoul National University Bundang Hospital. CT images were acquired 3 mm of thickness in the same condition and the treatment plan was performed by Eclipse (Ver.7.1, Varian, Palo Alto, USA). Two plans were generated under same planing objectives, dose volume constraints, and eight fields setting: (1) The low energy plan (LEP) created using 6 MV beam alone, (2) the partially used high energy plan (PHEP) created partially using 15 MV beam at two posterior oblique fields with deeper penetration depths, while 6 MV beam was used at the rest of fields. The plans for LEP and PHEP were compared in terms of coverage, conformity index (CI) and homogeneity index (HI) for planning target volume (PTV). For organs at risk (OARs), $D_{mean}$ and $D_{50%}$ were analyzed on both parotid glands and $D_{max}$, $D_{1%}$ for spinal cord were analyzed. Integral dose (ID) and total monitor unit (MU) were compared as addition parameters. For the comparing dose to normal tissue of posterior neck, the posterior-normal tissue volume (P-NTV) was set on the patients respectively. The $D_{mean}$, $V_{20Gy}$ and $V_{25Gy}$ for P-NTV were evaluated by using dose volume histogram (DVH). Results: The dose distributions were similar with regard to coverage, CI and HI for PTV between the LEP and PHEP. No evident difference was observed in the spinal cord. However, the $D_{mean}$, $D_{50%}$ for both parotid gland were slightly reduced by 0.6%, 0.7% in PHEP. The ID was reduced by 1.1% in PHEP, and total MU for PHEP was 1.8% lower than that for LEP. In the P-NTV, the $D_{mean}$, $V_{20Gy}$ and $V_{25Gy}$ of the PHEP were 1.6%, 1.8% and 2.9% lower than those of LEP. Conclusion: Dose to some OARs and a normal tissue, total monitor unit were reduced in IMRT plan with partially used high energy photon. Although these reduction are unclear how have a clinical benefit to patient, application of the partially used high energy photon could improve the overall plan quality of IMRT for head and neck cancer.

  • PDF

A Study on the Curriculum for Record Management Science Education - with focus on the Faculty of Cultural Information Resources, Surugadai University; Evolving Program, New Connections (기록관리학의 발전을 위한 교육과정연구 -준하태(駿河台)(스루가다이)대학(大學)의 경우를 중심(中心)으로-)

  • Kim, Yong-Won
    • Journal of Korean Society of Archives and Records Management
    • /
    • v.1 no.1
    • /
    • pp.69-94
    • /
    • 2001
  • The purpose of this paper is to provide an overview of the current status of the records management science education in Japan, and to examine the implications of the rapid growth of this filed while noting some of its significant issues and problems. The goal of records management science education is to improve the quality of information services and to assure an adequate supply of information professionals. Because records management science programs prepare students for a professional career, their curricula must encompass elements of both education and practical training. This is often expressed as a contrast between theory and practice. The confluence of the social, economic and technological realities of the environment where the learning takes place affects both. This paper reviews the historical background and current trends of records management science education in Japan. It also analyzes the various types of curriculum and the teaching staff of these institutions, with focus on the status of the undergraduate program at Surugadai University, the first comprehensive, university level program in Japan. The Faculty of Cultural Information Resources, Surugadai University, a new school toward an integrated information disciplines, was opened in 1994, to explore the theory and practice of the management diverse cultural information resources. Its purpose was to stimulate and promote research in additional fields of information science by offering professional training in archival science, records management, and museum curatorship, as well as librarianship. In 1999, the school introduced a master program, the first in Japan. The Faculty has two departments and each of them has two courses; Department of Sensory Information Resources Management; -Sound and Audiovisual Information Management, -Landscape and Tourism Information Management, Department of Knowledge Information Resources Management; -Library and Information Management, -Records and Archives Management The structure of the entire curriculum is also organized in stages from the time of entrance through basic instruction and onwards. Orientation subjects which a student takes immediately upon entering university is an introduction to specialized education, in which he learns the basic methods of university education and study, During his first and second years, he arranges Basic and Core courses as essential steps towards specialization at university. For this purpose, the courses offer a wide variety of study topics. The number of courses offered, including these, amounts to approximately 150. While from his third year onwards, he begins specific courses that apply to his major field, and in a gradual accumulation of seminar classes and practical training, puts his knowledge grained to practical use. Courses pertaining to these departments are offered to students beginning their second year. However, there is no impenetrable wall between the two departments, and there are only minor differences with regard requirements for graduation. Students may select third or fourth year seminars regardless of the department to which they belong. To be awarded a B.A. in Cultural Information Resources, the student is required to earn 34 credits in Basic Courses(such as, Social History of Cultural Information, Cultural Anthropology, History of Science, Behavioral Sciences, Communication, etc.), 16 credits in Foreign Languages(including 10 in English), 14 credits on Information Processing(including both theory and practice), and 60 credits in the courses for his or her major. Finally, several of the issues and problems currently facing records management science education in Japan are briefly summarized below; -Integration and Incorporation of related areas and similar programs, -Curriculum Improvement, -Insufficient of Textbooks, -Lack of qualified Teachers, -Problems of the employment of Graduates. As we moved toward more sophisticated, integrated, multimedia information services, information professionals will need to work more closely with colleagues in other specialties. It will become essential to the survival of the information professions for librarians to work with archivists, record managers and museum curators. Managing the changes in our increasingly information-intensive society demands strong coalitions among everyone in cultural Institutions. To provide our future colleagues with these competencies will require building and strengthening partnerships within and across the information professions and across national borders.

The Actual State and the Utilization for Dental Radiography in Korea (국내 치과방사선의 현황 및 이용 실태)

  • Shin, Gwi-Soon;Kim, You-Hyun;Lee, Bo-Ram;Kim, Se-Young;Lee, Gui-Won;Park, Chang-Seo;Park, Hyok;Chang, Kye-Yong
    • Journal of radiological science and technology
    • /
    • v.33 no.2
    • /
    • pp.109-120
    • /
    • 2010
  • The purpose of this study was first to analyze the utilization of dental examination through questionnaire to develop a diagnostic reference level of patient doses for dental radiography in korea. 77 dental institutions were classified into three groups: A group for the dental hospitals of the college of dentistry (11 institutions), B group for dental hospitals (30 institutions) and C group for dental clinics (36 institutions). The results were as follows : The mean numbers of unit chairs and medical staffs were 140.2, 15.3 and 5.8 sets, 112.6, 7.3 and 1.7 dentists, 3.1, 0.5 and no one radiologic technologists, and 19.7, 12.5 and 3.3 dental hygienists in A, B and C groups, respectively. The mean numbers of dental X-ray equipments were 14.64, 3.21 and 2.19 in A, B and C groups, respectively. Intraoral dental X-ray unit was used the most, the following equipments were panoramic, cephalometric, and cone-beam CT units. The most used X-ray imaging system was also digital system (above 50%) in all three groups. Insight dental film (Kodak, USA) having high sensitivity was routinely used for periapical radiography. The automatic processor was not used in many dental institutions, but the film-holding device was used in many dental institutions. The utilization rates of PACS in A, B and C groups were 90.9%, 83.3% and 16.7% respectively, and the PACS software program was used the most PiView STAR (Infinitt, Korea). The annual mean number of radiographic cases in one dental institution in 2008 for A group was 6.8 times and 21.2 times more than those for B and C groups, and periapical and panoramic radiographs were taken mostly. Tube voltage (kVp) and tube current (mA) for periapical radiography were similar in all three groups, but exposure time in C group was 12.0 times and 3.5 times longer than those in B and C groups. The amount of radiation exposure in C group, in which dental hygienists take dental radiographs, was more than those in other groups. The exposure parameters for panoramic radiography were similar in all three groups. In conclusion, the exposure parameters in dental radiography should be determined with reference level, not past experiences. Use of automatic processor and film-holding devices reduces the radiation exposure in film system. The quality assurance of dental equipments are necessary for the reduction of the patient dose and the improvement of X-ray image quality.

A study of the plan dosimetic evaluation on the rectal cancer treatment (직장암 치료 시 치료계획에 따른 선량평가 연구)

  • Jeong, Hyun Hak;An, Beom Seok;Kim, Dae Il;Lee, Yang Hoon;Lee, Je hee
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.28 no.2
    • /
    • pp.171-178
    • /
    • 2016
  • Purpose : In order to minimize the dose of femoral head as an appropriate treatment plan for rectal cancer radiation therapy, we compare and evaluate the usefulness of 3-field 3D conformal radiation therapy(below 3fCRT), which is a universal treatment method, and 5-field 3D conformal radiation therapy(below 5fCRT), and Volumetric Modulated Arc Therapy (VMAT). Materials and Methods : The 10 cases of rectal cancer that treated with 21EX were enrolled. Those cases were planned by Eclipse(Ver. 10.0.42, Varian, USA), PRO3(Progressive Resolution Optimizer 10.0.28) and AAA(Anisotropic Analytic Algorithm Ver. 10.0.28). 3fCRT and 5fCRT plan has $0^{\circ}$, $270^{\circ}$, $90^{\circ}$ and $0^{\circ}$, $95^{\circ}$, $45^{\circ}$, $315^{\circ}$, $265^{\circ}$ gantry angle, respectively. VMAT plan parameters consisted of 15MV coplanar $360^{\circ}$ 1 arac. Treatment prescription was employed delivering 54Gy to recum in 30 fractions. To minimize the dose difference that shows up randomly on optimizing, VMAT plans were optimized and calculated twice, and normalized to the target V100%=95%. The indexes of evaluation are D of Both femoral head and aceta fossa, total MU, H.I.(Homogeneity index) and C.I.(Conformity index) of the PTV. All VMAT plans were verified by gamma test with portal dosimetry using EPID. Results : D of Rt. femoral head was 53.08 Gy, 50.27 Gy, and 30.92 Gy, respectively, in the order of 3fCRT, 5fCRT, and VMAT treatment plan. Likewise, Lt. Femoral head showed average 53.68 Gy, 51.01 Gy and 29.23 Gy in the same order. D of Rt. aceta fossa was 54.86 Gy, 52.40 Gy, 30.37 Gy, respectively, in the order of 3fCRT, 5fCRT, and VMAT treatment plan. Likewise, Lt. Femoral head showed average 53.68 Gy, 51.01 Gy and 29.23 Gy in the same order. The maximum dose of both femoral head and aceta fossa was higher in the order of 3fCRT, 5fCRT, and VMAT treatment plan. C.I. showed the lowest VMAT treatment plan with an average of 1.64, 1.48, and 0.99 in the order of 3fCRT, 5fCRT, and VMAT treatment plan. There was no significant difference on H.I. of the PTV among three plans. Total MU showed that the VMAT treatment plan used 124.4MU and 299MU more than the 3fCRT and 5fCRT treatment plan, respectively. IMRT verification gamma test results for the VMAT plan passed over 90.0% at 2mm/2%. Conclusion : In rectal cancer treatment, the VMAT plan was shown to be advantageous in most of the evaluation indexes compared to the 3D plan, and the dose of the femoral head was greatly reduced. However, because of practical limitations there may be a case where it is difficult to select a VMAT treatment plan. 5fCRT has the advantage of reducing the dose of the femoral head as compared to the existing 3fCRT, without regard to additional problems. Therefore, not only would it extend survival time but the quality of life in general, if hospitals improved radiation therapy efficiency by selecting the treatment plan in accordance with the hospital's situation.

  • PDF