• Title/Summary/Keyword: 조형적 분석

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The Evaluation of Composite Dose using Deformable Image Registration in Adaptive Radiotherapy for Head and Neck Cancer (두경부 종양의 적응방사선치료시 변형영상정합을 이용한 합성선량 평가)

  • Hwang, Chul-Hwan;Ko, Seong-Jin;Kim, Chang-Soo;Kim, Jung-Hoon;Kim, Dong-Hyun;Choi, Seok-Yoon;Ye, Soo-Young;Kang, Se-Sik
    • Journal of radiological science and technology
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    • v.36 no.3
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    • pp.227-235
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    • 2013
  • In adaptive radiotherapy(ART), generated composite dose of surrounding normal tissue on overall treatment course which is using deformable image registration from multistage images. Also, compared with doses summed by each treatment plan and clinical significance is considered. From the first of May, 2011 to the last of July, 2012. Patients who were given treatment and had the head and neck cancer with 3-dimension conformal radiotherapy or intensity modulated radiotherapy, those who were carried out adaptive radiotherapy cause of tumor shrinkage and weight loss. Generated composite dose of surrounding normal tissue using deformable image registration was been possible, statistically significant difference was showed to mandible($48.95{\pm}3.89$ vs $49.10{\pm}3.55$ Gy), oral cavity($36.93{\pm}4.03$ vs $38.97{\pm}5.08$ Gy), parotid gland($35.71{\pm}6.22$ vs $36.12{\pm}6.70$ Gy) and temporomandibular joint($18.41{\pm}9.60$ vs $20.13{\pm}10.42$ Gy) compared with doses summed by each treatment plan. The results of this study show significant difference between composite dose by deformable image registration and doses summed by each treatment plan, composite dose by deformable image registration may generate more exact evaluation to surrounding normal tissue in adaptive radiotherapy.

Robust Planning of Intensity-modulated Proton Therapy for Prostate Cancer (전립선암 치료를 위한 세기조절 양성자 로버스트 치료계획)

  • Park, Su Yeon;Kim, Jong Sik;Park, Ju Young;Park, Won;Ju, Sang Gyu
    • The Journal of Korean Society for Radiation Therapy
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    • v.25 no.1
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    • pp.25-31
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    • 2013
  • Purpose: The aim of this study is to evaluate the dosimetric properties of robust planning strategy for plain intensity-modulated proton therapy (IMPT) taking into account of the uncertainties of effective proton range and set up error as compared to photon intensity-modulated radiation therapy (photon-IMRT) in prostate cancer treatment. Materials and Methods: The photon-IMRT (7 beams, step & shoot), plain-IMPT (2, 4, and 7 portals), and robust- IMPT plans, which was recalculated the plain-IMPT based on the uncertainties of range error (${\pm}5%$) and set up error (0.5 cm), were evaluated for five prostate cancer patients prescribed by 70 Gy/35 fractions. To quantitatively evaluate the dose distributions, several parameters such as maximum dose, minimum dose, mean dose, conformity index (CI), and homogeneity index (HI) for PTV as well as dose-volume index of VxGy for OARs were calculated from dose-volume histograms. Results: Robust-IMPT showed superior dose distributios in the PTV and OARs as compared to plain-IMPT and photon-IMRT. Like plain-IMPT, robust-IMPT were resulted in dose fluctuation around OARs, while better homogeneity and conformity in PTVs and lower mean dose in OARs as compared to photon-IMRT. Conclusion: In consideration with the effective range correction and set up movement using robustness in IMPT plan, the dosimetric uncertainties from plain-IMPT could substantially reduce and suggest more effective solutions than photon-IMRT in prostate cancer treatment.

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PTV Margins for Prostate Treatments with an Endorectal Balloon (전립선 암의 방사선치료 시 직장 내 풍선삽입에 따른 계획표적부피마진)

  • Kim, Hee-Jung;Chung, Jin-Beom;Ha, Sung-Whan;Kim, Jae-Sun;Ye, Sung-Joon
    • Radiation Oncology Journal
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    • v.28 no.3
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    • pp.166-176
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    • 2010
  • Purpose: To determine the appropriate prostate planning target volume (PTV) margins for 3-dimensitional (3D) conformal radiotherapy (CRT) and intensity-modulated radiation therapy (IMRT) patients treated with an endorectal balloon (ERB) under our institutional treatment condition. Materials and Methods: Patients were treated in the supine position. An ERB was inserted into the rectum with 70 cc air prior to planning a CT scan and then each treatment fraction. Electronic portal images (EPIs) and digital reconstructed radiographs (DRR) of planning CT images were used to evaluate inter-fractional patient's setup and ERB errors. To register both image sets, we developed an in-house program written in visual $C^{++}$. A new method to determine prostate PTV margins with an ERB was developed by using the common method. Results: The mean value of patient setup errors was within 1 mm in all directions. The ERB inter-fractional errors in the superior-inferior (SI) and anterior-posterior (AP) directions were larger than in the left-right (LR) direction. The calculated 1D symmetric PTV margins were 3.0 mm, 8.2 mm, and 8.5 mm for 3D CRT and 4.1 mm, 7.9 mm, and 10.3 mm for IMRT in LR, SI, and AP, respectively according to the new method including ERB random errors. Conclusion: The ERB random error contributes to the deformation of the prostate, which affects the original treatment planning. Thus, a new PTV margin method includes dose blurring effects of ERB. The correction of ERB systematic error is a prerequisite since the new method only accounts for ERB random error.

Objective Analysis of the Set-up Error and Tumor Movement in Lung Cancer Patients using Electronic Portal Imaging Device (폐암 환자에서 Electronic Portal Imaging Device를 이용한 자세 오차 및 종양 이동 거리의 객관적 측정)

  • Kim, Woo-Cheol;Chung, Eun-Ji;Lee, Chang-Geol;Chu, Sung-Sil;Kim, Gwi-Eon
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.69-76
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    • 1996
  • Purpose : The aim of this study is to investigate the random and systematic errors and tumor movement using electronic portal imaging device in lung cancer patients for the adequate margin in the treatment planning of 3-dimensional conformal therapy. Material and Methods : The electronic portal imaging device is matrix ion chamber type(Portal Vision, Varian). Ten patients of lung cancer treated with chest irradiation were selected for this study. Patients were treated in the supine position without immobilization device. All treatments were delivered by an 10 MV linear accelerator that had the portal imaging system mounted to its ganrty. AP or PA field Portal images were only analyzed. Radiation therapy field included the tumor, mediastinum and supraclavicular lymph nodes. A total of 103 portal images were analyzed for set-up deviation and 10 multiple images were analyzed for tumor movement because of respiration and cardiac motion. Result : The average values of setup displacements in the x, y direction was 1.41 mm, 1 78 mm, respectively. The standard deviation of systematic component was 4.63 mm, 4.11 mm along the x, y axis, respectively while the random component was 4.17 mm in the x direction and 3.31 mm in the y direction. The average displacement from respiratory movement was 12.2 mm with a standard deviation of 4.03 mm. Conclusion : The overall set-up displacement includes both random and systematic component and respiratory movement. About 10 mm, 25 mm margins along x, y axis which considered the set-up displacement and tumor movement were required for initial 3-dimensional conformal treatment planning in the lung cancer patients and portal images should be made and analyzed during first week of treatment, individually.

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Bladder Volume Variations in Patients Receiving Conformal Radiotherapy to Prostate (전립선암 환자의 방사선 치료 시 방광 체적 변화)

  • Lee, Re-Na;Lee, Ji-Hye;Lee, Kyung-Ja;Ji, Young-Hoon
    • Journal of Radiation Protection and Research
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    • v.33 no.2
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    • pp.61-65
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    • 2008
  • Objective: To reduce urinary side effects in prostate cancer patients receiving radiation, patients were asked to drink certain amount of water to maintain bladder volume constant and the bladder volumes were measured weekly using ultrasound scanner. Materials and Methods: Twenty-six patients with prostate cancer who received radiation between December 2002 and August 2007 were enrolled in this study. Thirteen patients were enrolled in experimental group. These patients were asked to drink 450 cc of water, one hour prior to simulation, CT scan, and treatment. The other thirteen patients were given no information about bladder filing. Bladder, prostate, and rectum were contoured on CT and volumes were calculated. 3D conformal treatment planning was performed and effective volumes of bladder were calculated when a prescription dose of 70.2 Gy was delivered. For the patients in experimental group, bladder volumes were measured weekly using ultrasound scanner for 6-8 weeks and the bladder volume variations were analyzed. Results: Average bladder volumes and standard deviations obtained at CT scanning were $283.5{\pm}114.0\;cc$ (40%) and $181.2{\pm}120.1\;cc$ (66%) in experimental and control groups, respectively. Although it was not statistically significant, there was correlation between the bladder volumes measured from CT and ultrasound. The volumes measured using ultrasound scanner were 62% lower than the volumes using CT images on average. There was significant variations in volumes measured weekly for 6-8 weeks. It ranged between 33 - 75 %. Conclusion: Our results showed that it is possible to obtain larger bladder volume if they are asked to drink certain amount of water prior to CT scan. However, patients were unable to maintain constant bladder volumes over the 6-8 weeks of treatment period although they were asked to drink constant amount of water.

A Study on the Production of Royal Seals during the Reign of King (Emperor) Gojong (r. 1863-1907) (고종 연간(1863~1907) 제작 어보(御寶) 연구)

  • JE, Jihyeon
    • Korean Journal of Heritage: History & Science
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    • v.54 no.3
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    • pp.126-149
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    • 2021
  • The reign of King (later Emperor) Gojong of the Joseon dynasty (later the Korean Empire), which lasted from 1863 to 1907, was a period of turmoil caused by political and social instability at home and military incursions by foreign powers. It was also a period in which Joseon was proclaimed as the Korean Empire and, accordingly, the royal seals of the dynasty underwent a major change. Records show that some 135 seals were produced during the reign of Gojong. The present study of the makers and styles of the royal seals aims to reveal a wealth of information on the seals, which typically had handles in the shape of either a turtle or dragon. Among the seal makers of this era, Jeon Heung-gil was particularly highly regarded as a Golden Royal Seal Artisan (Geumbojang) because he was highly skilled at making both turtle and dragon handles. Kim Eun-seok, a master Jade Royal Seal Artisan (Okbojang), also excelled in the production of turtle and dragon handles for his jade seals. Another master Jade Royal Seal Artisan, Yi Jung-ryeo, is noteworthy because he developed a new style of jade royal seals, which eventually became the dominant style after 1890, when Kim Eun-seok was not active. Furthermore, after the 1890s, his style was also applied to the production of the gold royal seals and developed as the dominant style. Regarding the dragon handles adopted after the proclamation of the Korean Empire, both the golden and the jade royal seals were made in the same style by the same artisans in the service of the Joseon dynasty. They adopted the style of Chinese imperial seals when they began making seals with dragon handles for the Korean Empire, although the basic shapes of both handle and dragon were copied from those made during the Joseon period. As a ceremonial object symbolizing the authority and legitimacy of the royal or imperial family, the style of the royal seals was influenced mainly by changes in the political situation at home and abroad. As Gojong's reign was a period in which more royal seals were made than in the reign of any other ruler, the seals originating from his reign constitute a richer source of information about the efforts of the dynasty to preserve the tradition while effectively dealing with the changes of the new era.

Assessment of the Usefulness of an IMRT Plan Using a Shell-Type Pseudo Target with Patients in Stage III or IV of NSCLC (비소세포폐암 III, IV기 환자에 있어서 Shell-Type Pseudo Target을 이용한 세기 조절 방사선치료계획기법의 유용성 평가)

  • Lee, Sang-Bong;Park, Ki-Ju;Park, Du-Chan;Kim, Man-Wo;Kim, Jun-Gon;Noh, Sung-Hwan
    • The Journal of Korean Society for Radiation Therapy
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    • v.24 no.2
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    • pp.95-106
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    • 2012
  • Purpose: The objective of this study was to investigate the usefulness of an IMRT treatment plan according to whether there was a shell-type pseudo target during radiation therapy for patients in Stage III or IV of non-small cell lung cancer (NSCLC). Materials and Methods: After setting an IMRT (Intensity-Modulated Radiation Therapy, IMRT) plan for when there was a shell-type pseudo target (SPT) and when there was none (WSPT) with 22 patients in Stage III or IV of NSCLC, the investigator analyzed dose-volume histograms (DVHs) and made assessment with dosimetric comparisons such as homogeneity index (HI) inside the tumor target, conformity index (CI) of the tumor target, spinal cord maximum dose, Esophagus $V_{50%}$, mean lung dose (MLD), and $V_{40%}$, $V_{30%}$, $V_{20%}$, $V_{10%}$, $V_{5%}$. Results: The mean CI of WSPT and SPT was $1.22{\pm}0.04$ and $1.16{\pm}0.032$ ($.000^*$), respectively, and the mean HI of WSPT and SPT was $1.06{\pm}0.015$ and $1.07{\pm}0.014$ ($.000^*$), respectively. In SPT, the mean of each CI difference decreased by $-5.16{\pm}2.54%$, while HI increased by average $0.81{\pm}0.47%$. Esophagus $V_{50%}$ recorded $14.54{\pm}12.01%$ (WSPT) and $12.14{\pm}11.09%$ ($.000^*$, SPT) with the mean of SPT differences dropping by $-26.37{\pm}25.05%$. Mean spinal cord maximum dose was $3,898.44{\pm}1,075.0$ cGy (WSPT) and $3,810.8{\pm}1,134.9$ cGy ($.004^*$, SPT) with SPT dropping by average $-3.36{\pm}5.81%$. As for lung $V_{X%}$, the mean of $V_{5%}$ and $V_{10%}$ differences was $-1.62{\pm}2.29%$ ($.006^*$) and $-1.98{\pm}5.02%$ ($.005^*$), respectively with SPT making a decrease. The mean of V20%, V30%, and V40% differences was $-3.51{\pm}3.07%$ ($.000^*$), $-4.84{\pm}6.01%$ ($.000^*$), and $-6.16{\pm}8.46%$ ($.001^*$), respectively, with SPT making a decrease with statistical significance. In MLD assessment, SPT also dropped by average $-2.83{\pm}2.41%$ ($.000^*$). Those results show that SPT allows for mean 169 cGy (Max: 547 cGy, Min: 6.4 cGy) prescription dose. Conclusion: An IMRT treatment plan with SPT during radiation therapy for patients in Stage III or IV of NSCLC will help to reduce the risk of lung toxicity and radiation-induced pneumonia by cutting down radiation doses entering the normal lung, reduce the local control failure rate during radiation therapy due to increasing prescription doses to a certain degree, and increase treatment effects.

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