• Progress in Medical Physics
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• v.14 no.3
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• pp.184-188
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• 2003

It is strongly recommended that periodic quality assurance should be carried out in the Gamma Knife that is used in radiosurgery since high radiation is delivered in one session. Since the protocols for Gamma Knife recommended by associations or agencies on quality assurance are absent in Korea, hospitals possessing the Gamma Knife have developed their own protocols. In order to develop a quality assurance protocol suitable for Korea, we reviewed the protocols of the Gamma Knife manufacturer, USA and Japan. we categorized the periodic items into three parts,: radiation dose, mechanical and safety part. The USA recommended and regulated more strict than the manufacturer. Japan recommended the items and frequency based on the USA. In conclusion, we tried to suggest a basic Gamma Knife quality assurance protocol suitable for Korea.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.199-206
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• 2014

Purpose : According to the rapid increase recently in image-guided radiation therapy, It is necessary to control of the image guidance system completely. In particular for the main subject to the accuracy of image guided radiation therapy device to be done essentially the quality assurance. We made efficient phantom in AMC for the management of the accurate and efficient. Materials and Methods : By setting up of five very important as a quality assurance inventory of the Image guidance system, we made (AMC G-Box) phantom for quality assurance efficient and accurate. Quality assurance list were the Iso-center align, the real measurement, the center align of four direction, the accuracy of table movement and the reproducibility of Hounsfield Unit. The rectangular phantom; acrylic with a thickness of 1 cm to $10cm{\time}10cm{\time}10cm$ was inserted the three materials with different densities respectively for measure the CBCT HU. The phantom was to perform a check of consistency centered by creating a marker that indicates the position of the center fixed. By performing the quality assurance using the phantom of existing, comparing the resulting value to the different resulting value using the AMC G-Box, experiment was analyzed time and problems. Therapy equipment was used Varian device. It was measured twice at 1-week intervals. Results : When implemented quality assurance of an image guidance system using AMC G-Box and a phantom existing has been completed, the quality assurance result is similar in $0.2mm{\pm}0.1$. In the case of the conventional method, it was 45 minutes at 30 minutes. When using AMC G-Box, it takes 20 minutes 15 minutes, and declined to 50% of the time. Conclusion : The consistency and accurate of image guidance system tend to decline using device. Therefore, We need to perform thoroughly on the quality assurance related. It needs to be checked daily to consistency check especially. When using the AMC G-Box, It is possible to enhance the accuracy of the patient care and equipment efficiently performing accurate quality assurance.

• The Journal of the Korea Contents Association
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• v.7 no.7
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• pp.114-123
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• 2007

The increasing use of computed tomography (CT) as a diagnostic tool creates the need from and efficient means of evaluating the performance of the CT scanner now in use. Accordingly, acceptance testing and quality assurance of CT is of great importance. The aim of this study is to analyze of AAPM CT performance phantom in the CT accreditation program. The modular phantom offers the CT system with which to measure eight performance parameters. The parameters are listed of CT attenuation coefficient of water, noise, uniformity, spatial resolution, contrast resolution, slice thickness (5 and 10 mm), artifacts and alignment. The phantom evaluation was done by two radiologists. The acceptance testing protocol described here in demonstrates the successful of the guidelines for the quality assurance using AAPM CT performance phantom. We need to be upgraded for the CT image quality and make the standard reference of the quality assurance in the CT.

• Journal of radiological science and technology
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• v.41 no.1
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• pp.39-45
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• 2018

The purpose of this study is to evaluate the usefulness of a software-based quality assurance system based on Volumetric Modulated Arc Therapy treatment plan. Evaluate treatment plan through the D VH analysis, PTV mean dose ($D_{mean}$) and PTV 95% dose($D_{95}$) compare the MFX based on original treatment plan, Average error rate was $0.9{\pm}0.6%$, $1.0{\pm}0.8%$, respectively. Measuring point dose using phantom and ion chamber, the average error rate between the ionization chamber and MFX was $0.9{\pm}0.7%$, $1.1{\pm}0.7%$ (high dose region), $1.1{\pm}0.9%$, $1.2{\pm}0.7%$ (low dose region). The average gamma though of MFX and $Delta^{4PT}$ is $98.7{\pm}1.2%$, $98.4{\pm}.3%$, respectively. Through this study, A software based QA system that simplifies hardware based QA procedures that involve a lot of time and effort. It can be used as a simple and useful tool in clinical practice.

• Journal of Korea Association of Health Promotion
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• v.4 no.1
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• pp.60-67
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• 2006

Purpose : Asian Quality Assurance Survey program(AQuAS) is and activity of Asian Network for Clinical Laboratory Standardization and Harmonization(ANCLS) which had begun her first colloquium in 1999 in Jakarta, Indonesia by laboratory physicians led by Professors Noriyuki Tatsumi and Yoshinori Funahara with themes of standardization and harmonization of clinical laboratories in Asia. Methods : AQuAS had begun its first survey in July. 2001 and done November and March, three times per year in the fields of Chemistry, Hematology. Coagulation and Urinalysis. As of June 2006 the 15th survey have been completed. Korean Association of Health Promotion(KAHP) had participated in it since July, 2004 in the fields of chemistry, hematology and urinalysis.ゝ⨀

• Journal of Radiation Protection and Research
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• v.35 no.1
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• pp.34-42
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• 2010

With the expanded use of radiation in modern medical practices, the most important issue in regards to efforts to reduce individual exposure dose is quality assurance. Therefore in order to study the present condition of quality assurance, the Gwangju Metropolitan City area was divided into five districts each containing ten hospitals. Four experiments were conducted: a reproducibility experiment for kVp, mA, and examination time (sec) intensity of illumination; half-value layer (HVL) measurement; and beam perpendicularity test matching experiment. The tube voltage reproducibility experiment for all fifty hospitals resulted in a 95.33% passing rate and mA and examination time both resulted in a 77.0% passing rate. The passing rate for intensity of illumination was 86.0% and 52.0% for HVL, which was the lowest passing rate of all four factors. For the beam perpendicularity test matching experiment, generally the central flux is matched to within $1.5^{\circ}$. Of all fifty hospitals 30.0% were beyond $3^{\circ}$. The results of the survey showed that 58% responded that they knew about quality assurance cycle. All fifty respondents stated that they have not received any training in regards to quality assurance at their current place of employment. Although quality assurance is making relative progress, the most urgent issue is awareness of the importance of quality assurance. Therefore, the implementation of professional training focusing on safety management and accurate quality assurance of radiation will reduce the exposure to radiation for radiologists and patients and higher quality imaging using less dosage will also be possible.

• Journal of Yeungnam Medical Science
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• v.25 no.2
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• pp.85-91
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• 2008

Intensity-modulated radiation therapy (IMRT) is believed to be one of the best radiation treatment techniques. IMRT is able to deliver fatal doses of radiation to the tumor region with minimal exposure of critical organs. It is essential to have a comprehensive quality assurance program to assure precision and accuracy in treatment, due to the character of IMRT. We applied quality assurance technique to the Eclipse treatment planning system and sought to determine its effectiveness in patient treatment planning. An acrylic phantom, film, and an ionization chamber were used in this study.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.59-64
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• 2010

We examined the accuracy and efficiency of phantom by applying the designed phantom in order to check daily quality assurance easily by objective criteria and to confirm daily quality assurance of linear accelerator, simulator, and CT-simulator. The results of 10 weeks of linear accelerator output dose using American Association of Physicists in Medicine(AAPM) daily quality assurance guide were measured within ${\pm}1%$ of error. Mechanical check of laser alignment, optical distance indicator(ODI), CT scanner laser and alignment of gantry lasers with the center of imaging plane were measured within ${\pm}1mm$. Daily average working time for daily quality assurance of radiation therapy equipments was 38 minutes. The designed phantom was easy to install and daily quality assurance was possible with only one installation. The aspects reproducibility and efficiency as well as accuracy of quality assurance were excellent.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.2
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• pp.137-144
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• 2008

Positron emission tomography-computed tomography (PET/CT) provides both functional and anatomical images of high quality non-invasively with better precision in localization than PET alone. Increase in the use of PET/CT, coupled with increasing concerns about the quality of medical services accrued the demands for accurate evaluation of system performance and quality assurance. Thus, well designed programs for performance evaluation and quality assurance are needed. Widely used protocols for performance evaluation of PET are the methods proposed by National Electrical Manufacturers Association (NEMA) in 1994 and 2001. In addition, in order to maintain high quality of PET/CT images, quality assurance programs including periodic (daily, monthly, and yearly). Therefore, in this article, the methods and present state of performance evaluation and quality assurance of PET/CT are reviewed.

• Progress in Medical Physics
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• v.15 no.4
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• pp.186-191
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• 2004

The periodic Quality Assurance (QA) of each radiation treatment related equipments is important one, but quality assurance of the radiation treatment planning system (RTPS) is still not sufficient rather than other related equipments in clinics. Therefore, this study will present and test the periodic QA program to compare, evaluation the efficiency of the treatment planning systems. This QA program is divided to terms for the input, output devices and dosimetric data and categorized to the weekly, monthly, yearly and non-periodically with respect to the job time, frequency of error, priority of importance. CT images of the water equivalent solid phantom with a heterogeneity condition are input into the RTPS to proceed the test. The actual measurement data are obtained by using the ion chamber for the 6 MV, 10 MV photon beam, then compared a calculation data with a measurement data to evaluate the accuracy of the RTPS. Most of results for the accuracy of geometry and beam data are agreed within the error criteria which is recommended from the various advanced country and related societies. This result can be applied to the periodic QA program to improve the treatment outcome as a proper model in Korea and used to evaluate the accuracy of the RTPS.