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  • Title/Summary/Keyword: 선량적인 영향

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Evaluation on Usefulness of Applying Body-fix to Liver Cancer Patient in Tomotherapy (간암환자의 토모치료시 Body-fix 사용유무에 따른 유용성 평가)

  • Oh, Byeong-Cheon;Choi, Tae-Gu;Kim, Gi-Chul
    • The Journal of Korean Society for Radiation Therapy
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    • v.22 no.1
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    • pp.11-18
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    • 2010
  • Purpose: In every time radiation therapy set up errors occur because internal anatomical organs move due to breathing and change of patient's position. These errors may affect the change of dose distribution between target area and normal structure. This study investigates the usefulness of body-fix in clinical treatment. Materials and Methods: Among 55~60 aged male patients who has hepatocellular carcinoma in area of liver's couinaud classification, we chose 10 patients and divided two groups by using body-fix or not. When applying body-fix, we maintained a vacuum of 80 mbar pressure by using vacuum pump (Medical intelligence, Germany). Patients had free breathing with supine position. After working to fuse and consist MV-CT (megavoltage computed tomography) with KV-CT (kilovoltage computed tomography) obtained by 5 times treatments, we compared and analyzed set up errors occurred to (Right to Left, RL) of X axis, (Anterioposterio, AP) of Z axis, (Cranicoudal, CC) of Y axis. Results: Average Set up errors through image fusion showed that group A moved 0.3±1.1mm (Cranicoudal, CC), 1.1±0.7mm (Right to Left, RL), 0.2±0.7mm (Anterioposterio, AP) and group B moved 0.62±1.94mm (Cranicoudal, CC), 3.62±1.5mm (Right to Left, RL), 0.22±1.2mm (Anterioposterio, AP). Deviations of X, Y and Z axis directions by applying body-fix indicated that maximum X axis was 5.5 mm, Y axis was 19.8 mm and Z axis was 3.2 mm. In relation to analysis of error directions, consistency doesn't exist for every patient but by using body-fix showed that the result of stable aspect in spite of changes of everyday's patient position and breathing. Conclusion: Using body-fix for liver cancer patient is considered effectively for tomotherapy. Because deviations between group A and B exist but they were stable and regular.

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The Results of Radiation Therapv for Adenocarcinoma of the Uterine Cervix (자궁경부 선암 환자에 대한 생존율과 실패양상 분석)

  • Lee, Ho-Jun;Kim, Jin-Hee;Kim, Ok-Bae
    • Radiation Oncology Journal
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    • v.17 no.1
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    • pp.16-22
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    • 1999
  • Purpose : This study was done to analyze prognostic factors and patterns of failure of patients with histologically confirmed adenocarcinoma of the uterine cervix. Materials and Methods : From June 1988 to December 1990, a retrospective analysis was undertaken for 45 patients who were treated with curative radiation therapy for adenocarcinoma of the uterine cervix at the department of Therapeutic Radiology of Keimyung University Hospital. According to FIGO staging classification, f2 patients were stage Ib, 9 patients were lla, 19 patients were IIB, and 5 patients were lIIb. Median age of the patients was 54 years. The radiation therapy consisted of a combination of external and intracavitary irradiation. Only the pelvis was treated for external irradiation, but 6 patients were treated with extended field irradiation including paraaortic nodes. Intracavitary irradiation was performed with high dose rate sources (Co-60). Neoadiuvant chemotherapy was undertaken for 10 patients. Median and maximum follow-up duration was 64 and 116 months, respectively. Results : The overall 5-year survival rate was 55.2%, and the 5-year survival rates for stage Ib, IIa, IIb, and IIIb were 100%, 50.8%, 46.8%, and 40% (3-year survival rate), respectively. Of the many clinicopathologic variables evaluated for prognosis, only the stage and the tumor size were significant prognostic factors. Statistically, pelvic failure rates for stage Ib, IIa, IIb, and IIIb were 0%, 33.3%, 57.9%, and 60%, respectively. Distant metastasis rates were 0%, 33.3%, 21.1%, and 40% for stage Ib, IIa, IIb, and IIIb, respectively. Especially the 6 patients who were irradiated with extended field to treat the paraaortic nodes were free of distant metastasis all. But, 9 patients (23.1%) of the 39 patients who were not irradiated the paraaortic nodes were suffered and expired from uncontrolled distant metastasis. Conclusions : As compared with other studies, the survival rates were similar, but distant metastasis rates including paraaortic nodes metastasis were likely somewhat higher than expected, especially for patients with stage II. So, we think that the effect of prophylactic paraaortic nodes irradiation should be studied prospectively, especially for patients with pelvic nodes involvement or advanced stage of disease.

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Results of Concurrent Chemoradiotherapy and Intraluminal Brachytherapy in Esophageal Carcinoma - Retrospective Analysis with Respect to Survival - (식도암에서 동시 항암화학방사선요법과 관내근접치료의 결과 -생존율을 중심으로 한 후향적 분석-)

  • Nam Taek-Keun;Nah Byung-Sik;Chung Woong-Ki;Ahn Sung-Ja;Song Ju-Young
    • Radiation Oncology Journal
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    • v.22 no.1
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    • pp.25-32
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    • 2004
  • Purpose : Evaluate the efficacies and toxicities of concurrent chemoradiotherapy (CCRT), with or without intraluminal brachytherapy (ILB), using a retrospective analysis in esophageal carcinomas with respect to survival. Materials and Methods : From April 1995 to July 2001, a total of 65 patients, diagnosed with an esophageal carcinoma, were treated by CCRT, with 21 also treated by ILB after CCRT. External radiotherapy was peformed using 6 or 10 MV X-rays, with a dose range of 46.8 \69.6 Gy (median; 59.4). The ILB was peformed using high-dose-rate brachytherapy with Ir-192. The fractionation of ILB was 3 Gy by 4, or 5 Gy by 2 fractions. Cisplatin (75mg/m2) was given on each first day of weeks 1, 5, 9 and 13, and 5-FU (1,000mg/m2) as a continuous infusion for the first 4 days of each course. Results : The median survival time of all patients was 15 months, and the 1, 2 and 3-year survival rates were 55.4, 29.2 and 20.7%, respectively. The 2-year survival rates of the patients with and without ILB were 33.3 and 27.3%, respectively (p=0.80). The 2-year survival rates of the patients with a complete, partial and no response were 44.1, 13.8 and 0%, respectively (p=0.02). The response to treatment was the only significant factor affecting the overall survival from a multivariate analysis. Conclusion : This study has shown that the survival outcomes of CCRT were much better than previous results with radiotherapy alone. However, the addition of ILB after CCRT showed no advantage over that of CCRT alone.

The Significance of VEGF Expression in Stage II Carcinoma of Uterine Cervix Treated with Definitive Radiotherapy (자궁경부암 환자의 근치적 방사선치료 시 VEGF 발현의 임상적 의의)

  • Park Won;Choi Yoon-La;Huh Seung-Jae;Yoon Sang-Min;Park Young-Je;Nam Hee-Rim;Ahn Yong-Chan;Lim Do-Hoon;Park Hee-Chul
    • Radiation Oncology Journal
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    • v.24 no.1
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    • pp.37-43
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    • 2006
  • Purpose: We wanted to determine the clinical characteristics and prognosis according to the VEGF expression in stage II cervical carcinoma patients treated with definitive radiotherapy. Materials and Methods: We enrolled 31 patients who were diagnosed with cervical cancer from 1995 to 2003 at Samsung Medical Center and their paraffin block tissue samples were available for study. The median age of the patients was 65 years. The mean tumor size was 4.1 cm (range:1.28.2cm). Seven patients (22.6%) were suspected of having pelvic lymph node metastasis. An external beam irradiation dose of 45-56.4 Gy was administered to the whole pelvis with a 15 MV linear accelerator, and an additional 24 Gy was given to point A by HDR intracavitary brachytherapy. VEGF staining was defined as positive when more than 10% of the tumor cells were stained. The median follow-up duration was 58 months. Results: A positive VEGF expression was observed in 21 patients (67.7%), There was no significant correlation between the VEGF expression and pelvic lymph node metastasis, tumor size and the response of radiotherapy. During follow-up, 7 patients had recurrence. The complete response rate was not significant between the VEGF(-) and VEGF(+) tumors. However, the VEGF(+) tumors showed a significantly higher recurrence rate in comparison with the VEGF(-) tumors (p=0.040), The three year disease-free survival rates were 100% and 66.7%, respectively, for patients with VEGF(-) or VEGF(+) tumor (p=0.047), Conclusion: The VEGF expression was a significant factor for recurrence and disease-free survival. However, the significance of the VEGF expression is still controversial because of the various definitions of VEGF expression and the mismatches of the clinical data in the previous studies.

Changes of Pork Antigenicity by Heat, Pressure, Sonication, Microwave, and Gamma Irradiation (물리적 처리에 의한 돼지고기의 항원성 변화)

  • Kim, Seo-Jin;Kim, Koth-Bong-Woo-Ri;Song, Eu-Jin;Lee, So-Young;Yoon, So-Young;Lee, So-Jeong;Lee, Chung-Jo;Park, Jin-Gyu;Lee, Ju-Woon;Byun, Myung-Woo;Ahn, Dong-Hyun
    • Food Science of Animal Resources
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    • v.29 no.6
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    • pp.709-718
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    • 2009
  • The purpose of this study was to search for physical treatments to reduce allergenicity of pork. Physical treatments such as heating, autoclave, microwave, sonication, and irradiation have been used for food processing or reduction of allergenicity. The porcine serum albumin (PSA), known as a major allergen in pork, was extracted after physical treatments. The antigenicity of pork extracts by heating (80 and 100C for 20 min), autoclave (121C for 5, 10, and 30 min), and microwave (for 5 and 10 min) was significantly decreased. Especially, the binding ability of p-IgG to pork extracts by autoclave for 30 min showed the greatest decrease (about 3%) in physical treatments. However, the antigenicity of pork was unaffected by sonication and irradiation treatment. These results indicated that the autoclave treatment was the most effective method to reduce the antigenicity of pork.

Comparison Evaluation of Image Quality with Different Thickness of Aluminum added Filter using GATE Simulation in Digital Radiography (GATE 시뮬레이션을 사용한 알루미늄 부가필터 두께에 따른 Digital Radiography의 영상 화질 비교 평가)

  • Oh, Minju;Hong, Joo-Wan;Lee, Youngjin
    • Journal of the Korean Society of Radiology
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    • v.13 no.1
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    • pp.81-86
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    • 2019
  • In X-ray image, the role of filtration through the filter is to reduce the exposure of the patient by using photon which is useful in formation of the image, and at the same time, enhance the contrast of the image. During interaction between photon and object, low energy X-rays are absorbed from the site of a few cm of the first patient's tissue, and high energy X-rays are the one which form the image. Therefore, the radiation filter absorbs low energy X-ray in order to lower the exposure of the patient and improve the quality of the image. The purpose of this study is to compare the effect on the image quality by differences of added filter through simulation image and actual radiation image. For that purpose, we used Geant4 Application for Tomographic Emission (GATE) as a tool for Monte Carlo simulation. We set actual size, shape and material of Polymethylmethacrylate (PMMA) Phantom on GATE and differentiated the parameter of added filter. Also, we took image of PMMA phantom with same parameter of added filter by digital radiography (DR). Than we performed contrast-to-noise ratio (CNR) evaluation on both simulation image and actual DR image by Image J. Finally, we observed the effect on image quality due to different thickness of added filter, and compared two images' CNR evaluation's transitions of change. The result of this experiment showed decreasing in the progress of CNR on both DR and simulation image. It is ultimately caused by decreasing in contrast on image. In theory, contrast decrease with kVp increased. Given that condition, this study found out that filter makes not only decreasing total dose by absorbing low energy of X-ray, but also increasing average energy of X-ray.

Image quality and usefulness evaluaton of 3D-CBCT and Gated-CBCT according to baseline changes for SBRT of Lung Cancer (폐암 환자의 정위체부방사선치료 시 기준선 변화에 따른 3D-CBCT(Cone Beam Computed-Tomography)와 Gated-CBCT의 영상 품질 및 유용성 평가)

  • Han Kuk Hee;Shin Chung Hun;Lee Chung Hwan;Yoo Soon Mi;Park Ja Ram;Kim Jin Su;Yun In Ha
    • The Journal of Korean Society for Radiation Therapy
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    • v.35
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    • pp.41-51
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    • 2023
  • Purpose: This study compares and analyzes the image quality of 3D-CBCT(Cone Beam Computed-Tomography) and Gated CBCT according to baseline changes during SBRT(Stereotactic Body RadioTherapy) in lung cancer patients to find a useful CBCT method for correcting movement due to breathing Materials and methods : Insert a solid tumor material with a diameter of 3 cm into the QUASARTM phantom. 4-Dimentional Computed-Tomography(4DCT) images were taken with a speed of the phantom at period 3 sec and a maximum amplitude of 20 mm. Using the contouring menu of the computerized treatment planning system EclipseTM Gross Tumor Volume was outlined on solid tumor material. Set-up the same as when acquiring a 4DCT image using Truebeam STxTM, breathing patterns with baseline changes of 1 mm, 3 mm, and 5 mm were input into the phantom to obtain 3D-CBCT (Spotlight, Full) and Gated-CBCT (Spotlight, Full) images five times repeatedly. The acquired images were compared with the Signal-to-Noise Ratio(SNR), Contrast-to-Noise Ratio(CNR), Tumor Volume Length, and Motion Blurring Ratio(MBR) based on the 4DCT image. Results: The average Signal-to-Noise Ratio, Contrast-to-Noise Ratio, Tumor Volume Length and Motion Blurring Ratio of Spotlight Gated CBCT images were 13.30±0.10%, 7.78±0.16%, 3.55±0.17%, 1.18±0.06%. As a result, Spotlight Gated-CBCT images according to baseline change showed better values than Spotligtht 3D-CBCT images. Also, the average Signal-to-Noise Ratio, Contrast-to-Noise Ratio, Tumor Volume Length and Motion Blurring Ratio of Full Gated CBCT images were 12.80±0.11%, 7.60±0.11%, 3.54±0.16%, 1.18±0.05%. As a result Full GatedCBCT images according to baseline change showed better values than Full 3D-CBCT images. Conclusion : Compared to 3D-CBCT images, Gated-CBCT images had better image quality according to the baseline change, and the effect of Motion Blurring Artifacts caused by breathing was small. Therefore, it is considered useful to image guided using Gated-CBCT when a baseline change occurs due to difficulty in regular breathing during SBRT that exposes high doses in a short period of time

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The Result of Radiotherapy in Esophageal Carcinoma (식도암의 방사선치료 성적)

  • Gil Hack Joon;Kay Chul Seung;Jang Jee Young;Yoon Sei Chul;Shinn Kyung Sub;Bahk Yong Whee
    • Radiation Oncology Journal
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    • v.10 no.2
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    • pp.193-204
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    • 1992
  • During the period between March 1983 and December 1990, 74 patients with esophageal carcinoma (EG) were treated with radiation therapy (RT) at the Department of Therapeutic Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College. Of these, 6 patients were lost to follow-up, and 13 patients were interrupted. So the remaining 55 patients were analyzed, retrospectively. 32 patients were irradiated with curative aim, 12 patients with palliative intent, 10 patients postoperatively, and 1 patient pre- and post-operatively. Among these 55 patients, 28 patients were treated with chemoradiation modality, and 27 patients with RT alone. All patients were followed for a minimum of 20 months or until death. Of 32 patients irradiated by curative aim, 22 patients (69%) showed partial remission (PR), 6 patients (19%) complete remission (CR). Overall mean survival and two-year survival rate were 15.6 months and 22%. With respect to sex, age, pathologic differentiation, tumor location, tumor size, stage, RT aim, RT response, RT dose, use of chemotherapy and functional categories (FC) of dysphagia at initiation of RT and at finishing RT: Tumor size, stage, RT response had great influences on prognosis and FC at finishing RT had a slight influence on prognosis. Especially, the mean survival and 2-year survival rate in patients with postoperative RT were 24.7 months and 63%, which could be compared with 29.1 months and 43% in radically treated patients with CR. And the mean survival duration and 2-year survival rate in patients irradiated with doses more than 60 Gy were 22.4 months and 29%, and 50~60 Gy were 12.2 months and 12%, respectively. However, no significant difference was shown statistically. Among 12 patients treated with palliative intent, 9 patients (75%) had good improvement in dysphagia and the mean duration of palliative response was 10.6 months.

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Examinations on Applications of Manual Calculation Programs on Lung Cancer Radiation Therapy Using Analytical Anisotropic Algorithm (Analytical Anisotropic Algorithm을 사용한 폐암 치료 시 MU 검증 프로그램 적용에 관한 고찰)

  • Kim, Jong-Min;Kim, Dae-Sup;Hong, Dong-Ki;Back, Geum-Mun;Kwak, Jung-Won
    • The Journal of Korean Society for Radiation Therapy
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    • v.24 no.1
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    • pp.23-30
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    • 2012
  • Purpose: There was a problem with using MU verification programs for the reasons that there were errors of MU when using MU verification programs based on Pencil Beam Convolution (PBC) Algorithm with radiation treatment plans around lung using Analytical Anisotropic Algorithm (AAA). On this study, we studied the methods that can verify the calculated treatment plans using AAA. Materials and Methods: Using Eclipse treatment planning system (Version 8.9, Varian, USA), for each 57 fields of 7 cases of Lung Stereotactic Body Radiation Therapy (SBRT), we have calculated using PBC and AAA with dose calculation algorithm. By developing MU of established plans, we compared and analyzed with MU of manual calculation programs. We have analyzed relationship between errors and 4 variables such as field size, lung path distance of radiation, Tumor path distance of radiation, effective depth that can affect on errors created from PBC algorithm and AAA using commonly used programs. Results: Errors of PBC algorithm have showned 0.2±1.0 and errors of AAA have showned 3.5±2.8. Moreover, as a result of analyzing 4 variables that can affect on errors, relationship in errors between lung path distance and MU, connection coefficient 0.648 (P=0.000) has been increased and we could calculate MU correction factor that is A.E=L.P 0.00903+0.02048 and as a result of replying for manual calculation program, errors of 3.5±2.8 before the application has been decreased within 0.4±2.0. Conclusion: On this study, we have learned that errors from manual calculation program have been increased as lung path distance of radiation increases and we could verified MU of AAA with a simple method that is called MU correction factor.

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Effects of Contrast Improvement on High Voltage Rectification Type of X-ray Diagnostic Apparatus (X선 진단장치의 고압정류방식이 대조도 향상에 미치는 영향)

  • Lee, Hoo-Min;Yoon, Joon;Kim, Hyun-Ju
    • Journal of radiological science and technology
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    • v.37 no.3
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    • pp.187-193
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    • 2014
  • The purpose of this study was to analyze the effect on the selectivity on of high-voltage rectification device that measured the performance of the grid, and the contrast improvement ability (K factor) by measuring the scattered radiation content of the transmitted X-rays. The scattered radiation generated when the X-ray flux comes from the diagnostic X-ray generator that passes through an object. Targeting four different rectifications of X-ray generators, the mean value of the tube voltage and the tube current was measured in order to maximize the accuracy of the generating power dose within the same exposure condition. Using fluorescence meter, the content of the scattered rays that are transmitted through the acrylic was measured depending on the grid usage. When grid is not used, the content of the scattered rays was the lowest (34.158%) with the single-phase rectifier, was increased with the inverter rectifier (37.043%) and the three-phase 24-peak rectification method (37.447%). The difference of the scattered radiation content of each device was significant from the lowest 0.404% to the highest 3.289% while using 8:1 grid, the content of the scattered ray was the lowest with the single content of the scattered ray was the lowest with the single-phase rectifier (18.258%), was increased with the rectifier (25.502%) and the 24-peaks rectification (24.217%). Furthermore, there was difference up to content 7.244% to the lowest content 1.285% within three-phase 24-peaks rectification, inverter rectifications, and single-phase rectifier depending on the selectivity of the grid. Drawn from the statistical analysis, there was a similar relationship between the contrast improvement factor and the K factor. As a result, the grid selectivity and the contrast were increased within the single-phase rectifier rather than the constant voltage rectifier.