• Title/Summary/Keyword: Target Coverage

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Comparison of Intensity-modulated Radiation Therapy (IMRT), Uniform Scanning Proton Therapy (USPT), and Intensity-modulated Proton Therapy (IMPT) for Prostate Cancer: A Treatment Planning Study (전립선 암 환자의 IMRT, USPT, 및 IMPT 기법에 따른 치료효과 비교)

  • Son, Kihong;Cho, Seungryong;Kim, Jin Sung;Han, Youngyih;Ju, Sang Gyu;Ahn, Sung Hwan;Shin, Eunhyuk;Shin, Jung Suk;Park, Won;Pyo, Hongryul;Choi, Doo Ho
    • Progress in Medical Physics
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    • v.24 no.3
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    • pp.154-161
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    • 2013
  • This study assessed compared photon and proton treatment techniques, such as intensity modulated radiation therapy (IMRT), uniform scanning proton therapy (USPT), and intensity modulated proton therapy (IMPT), for a total of 10 prostate cancers. All treatment plans delivered 70 Gy to 95% of the planned target volume in 28 fractions. IMRT plans had 7 fields for the step and shoot technique, while USPT and IMPT plans employed two equally weighted, parallel-opposed lateral fields to deliver the prescribed dose to the planned target. Inverse planning was then incorporated to optimize IMPT. The homogeneity index (HI) and conformity index (CI) for the target and the normal tissue complication probability (NTCP) for organ at risk (OAR) were calculated. Although the mean HI and CI for target were not significantly different for each treatment techniques, the NTCP of the rectum was 2.233, 3.326, and 1.707 for IMRT, USPT, and IMPT, respectively. The NTCP of the bladder was 0.008, 0.003, and 0.002 respectively. The NTCP values at the rectum and bladder were significantly lower using IMPT. Our study shows that using proton therapy, particularly IMPT, to treat prostate cancer could be beneficial compared to 7-field IMRT with similar target coverage. Given these results, radiotherapy using protons, particularly optimized IMPT, is a worthwhile treatment option for prostate cancer.

The dosimetric guide of treatment modalities for Left side breast irradiation after conservative surgery (좌측 유방암 방사선 치료 시 치료 기법에 따른 선량적 고찰)

  • Kim, Tae Min;Moon, Sung Kong;Kim, Li Zzy;Kim, Se Young;Park, Ryeung Hwang;Kim, Joo Ho;Cho, Jung Heui
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.153-160
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    • 2018
  • Purpose : We retrospectively analyzed doses of each radiation therapy technique used in the treatment for left breast cancer patients after partial mastectomy through dose results for normalorgans and tumor volume to use this as a clinical reference for radiation therapy of domestic left breast cancer patients. Materials and Methods : 40 patients who underwent partial mastectomy on left breast cancer were classified in 3 treatment methods. The treatment plan was evaluated by HI(homogeneity index), $D_{95%}$, and CI(conformity index), and the $V_{hot}$ for gross tumor volume and clinical target volume of each treatment method. In Cyberknife treatment, tumor volume was the same as high dose volume in the other techniques, so no consideration was given to clinical target volume. Treatment plan evaluation for normal organs were evaluated by mean dose on ipsilateral lung, heart, left anterior descending artery, opposite breast and lung, and non-target tissue. Result : Treatment with volumetric arc radiotherapy(VMAT) showed $95.84{\pm}0.75%$ of $D_{95%}$ on the clinical target volume, significantly higher than that of 3D-CRT. The $D_{95%}$ value of the total tumor volume was slightly higher than the other treatments. In Cyberknife treatment, the dose to the normal organs was significantly lower than other treatments. Overall, the maximum dose and mean dose to the heart were $26.2{\pm}6.12Gy$ and $1.88{\pm}0.2Gy$ in VMAT treatment and $20.25{\pm}9.35Gy$ and $1.04{\pm}0.19Gy$ in 3D-CRT therapy, respectively. Conclusion : In comparison on 3D-CRT and VMAT, most of the dosimetric parameters for the evaluation of the treatment plan showed similar values, so that there is no significant difference in treatment plan evaluation. It is possible to select the treatment method according to the patient's anatomical structure or possibility of breath control. Cyberknife treatment is very useful treatment for normal organs because of its accurate dose exposure to the tumor volume However, it has restrictions to treat the local area, to have relatively long treatment time and to involve invasive procedure.

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A Cost-effective Control Flow Checking using Loop Detection and Prediction (루프 검출 및 예측 방법을 적용한 비용 효율적인 실시간 분기 흐름 검사 기법)

  • Kim Gunbae;Ahn Jin-Ho;Kang Sungho
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.12
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    • pp.91-102
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    • 2005
  • Recently, concurrent error detection for the processor becomes important. But it imposes too much overhead to adopt concurrent error detection capability on the system. In this paper, a new approach to resolve the problems of concurrent error detection is proposed. A loop detection scheme is introduced to reduce the repetitive loop iteration and memory access. To reduce the memory overheat an offset to calculate the target address of branching node is proposed. Performance evaluation shows that the new architecture has lower memory overhead and frequency of memory access than previous works. In addition, the new architecture provides the same error coverage and requires nearly constant memory size regardless of the size of the application program. Consequently, the proposed architecture can be used as an cost effective method to detect control flow errors in the commercial on the shelf products.

Dosimetric Evaluation of 3-D Conformal and Intensity-modulated Radiotherapy for Breast Cancer after Conservative Surgery

  • Mansouri, Safae;Naim, Asmaa;Glaria, Luis;Marsiglia, Hugo
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.11
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    • pp.4727-4732
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    • 2014
  • Background: Breast cancers are becoming more frequently diagnosed at early stages with improved long term outcomes. Late normal tissue complications induced by radiotherapy must be avoided with new breast radiotherapy techniques being developed. The aim of the study was to compare dosimetric parameters of planning target volume (PTV) and organs at risk between conformal (CRT) and intensity-modulated radiation therapy (IMRT) after breast-conserving surgery. Materials and Methods: A total of 20 patients with early stage left breast cancer received adjuvant radiotherapy after conservative surgery, 10 by 3D-CRT and 10 by IMRT, with a dose of 50 Gy in 25 sessions. Plans were compared according to dose-volume histogram analyses in terms of PTV homogeneity and conformity indices as well as organs at risk dose and volume parameters. Results: The HI and CI of PTV showed no difference between 3D-CRT and IMRT, V95 gave 9.8% coverage for 3D-CRT versus 99% for IMRT, V107 volumes were recorded 11% and 1.3%, respectively. Tangential beam IMRT increased volume of ipsilateral lung V5 average of 90%, ipsilateral V20 lung volume was 13%, 19% with IMRT and 3D-CRT respectively. Patients treated with IMRT, heart volume encompassed by 60% isodose (30 Gy) reduced by average 42% (4% versus 7% with 3D-CRT), mean heart dose by average 35% (495cGy versus 1400 cGy with 3D-CRT). In IMRT minimal heart dose average is 356 cGy versus 90cGy in 3D-CRT. Conclusions: IMRT reduces irradiated volumes of heart and ipsilateral lung in high-dose areas but increases irradiated volumes in low-dose areas in breast cancer patients treated on the left side.

Dosimetric comparison of volumetric modulated arc therapy with robotic stereotactic radiation therapy in hepatocellular carcinoma

  • Paik, Eun Kyung;Kim, Mi-Sook;Choi, Chul Won;Jang, Won Il;Lee, Sung Hyun;Choi, Sang Hyoun;Kim, Kum Bae;Lee, Dong Han
    • Radiation Oncology Journal
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    • v.33 no.3
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    • pp.233-241
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    • 2015
  • Purpose: To compare volumetric modulated arc therapy of RapidArc with robotic stereotactic body radiation therapy (SBRT) of CyberKnife in the planning and delivery of SBRT for hepatocellular carcinoma (HCC) treatment by analyzing dosimetric parameters. Materials and Methods: Two radiation treatment plans were generated for 29 HCC patients, one using Eclipse for the RapidArc plan and the other using Multiplan for the CyberKnife plan. The prescription dose was 60 Gy in 3 fractions. The dosimetric parameters of planning target volume (PTV) coverage and normal tissue sparing in the RapidArc and the CyberKnife plans were analyzed. Results: The conformity index was $1.05{\pm}0.02$ for the CyberKnife plan, and $1.13{\pm}0.10$ for the RapidArc plan. The homogeneity index was $1.23{\pm}0.01$ for the CyberKnife plan, and $1.10{\pm}0.03$ for the RapidArc plan. For the normal liver, there were significant differences between the two plans in the low-dose regions of $V_1$ and $V_3$. The normalized volumes of $V_{60}$ for the normal liver in the RapidArc plan were drastically increased when the mean dose of the PTVs in RapidArc plan is equivalent to the mean dose of the PTVs in the CyberKnife plan. Conclusion: CyberKnife plans show greater dose conformity, especially in small-sized tumors, while RapidArc plans show good dosimetric distribution of low dose sparing in the normal liver and body.

Application of Intensity Modulated Radiation Therapy (IMRT) in Prostate Cancer (전립선암에서 강도변조방사선치료 (Intensity Modulated Radiation Therapy)의 적용)

  • Park Suk Won;Oh Do Hoon;Bae Hoon Sik;Cho Byung Chul;Park Jae Hong;Han Seung Hee
    • Radiation Oncology Journal
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    • v.20 no.1
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    • pp.68-72
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    • 2002
  • This study was done to implement intensity-modulated radiation therapy (IMRT) for the treatment of primary prostate cancer and to compare this technique with conventional treatment methods. A 72-year-old male patient with prostate cancer stage T2a was treated with IMRT delivered with dynamic multi-leaf collimation. Treatment was designed using an inverse planning algorithm, which accepts dose and dose-volume constraints for targets and normal structures. The IMRT plan was compared with a three-dimensional (3D) plan using the same 6 fields technique. Lower normal tissue doses and improved target coverage were achieved using IMRT at current dose levels, and facilitate dose escalation to further enhance locoregional control and organ movement during radiotherapy is an important issue of IMRT in prostate cancer.

Dosimetric comparison between modulated arc therapy and static intensity modulated radiotherapy in thoracic esophageal cancer: a single institutional experience

  • Choi, Kyu Hye;Kim, Jina;Lee, Sea-Won;Kang, Young-nam;Jang, HongSeok
    • Radiation Oncology Journal
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    • v.36 no.1
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    • pp.63-70
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    • 2018
  • Purpose: The objective of this study was to compare dosimetric characteristics of three-dimensional conformal radiotherapy (3D-CRT) and two types of intensity-modulated radiotherapy (IMRT) which are step-and-shoot intensity modulated radiotherapy (s-IMRT) and modulated arc therapy (mARC) for thoracic esophageal cancer and analyze whether IMRT could reduce organ-at-risk (OAR) dose. Materials and Methods: We performed 3D-CRT, s-IMRT, and mARC planning for ten patients with thoracic esophageal cancer. The dose-volume histogram for each plan was extracted and the mean dose and clinically significant parameters were analyzed. Results: Analysis of target coverage showed that the conformity index (CI) and conformation number (CN) in mARC were superior to the other two plans (CI, p = 0.050; CN, p = 0.042). For the comparison of OAR, lung V5 was lowest in s-IMRT, followed by 3D-CRT, and mARC (p = 0.033). s-IMRT and mARC had lower values than 3D-CRT for heart $V_{30}$ (p = 0.039), $V_{40}$ (p = 0.040), and $V_{50}$ (p = 0.032). Conclusion: Effective conservation of the lung and heart in thoracic esophageal cancer could be expected when using s-IMRT. The mARC was lower in lung $V_{10}$, $V_{20}$, and $V_{30}$ than in 3D-CRT, but could not be proven superior in lung $V_5$. In conclusion, low-dose exposure to the lung and heart were expected to be lower in s-IMRT, reducing complications such as radiation pneumonitis or heart-related toxicities.

Liver dose reduction by deep inspiration breath hold technique in right-sided breast irradiation

  • Haji, Gunel;Nabizade, Ulviye;Kazimov, Kamal;Guliyeva, Naile;Isayev, Isa
    • Radiation Oncology Journal
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    • v.37 no.4
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    • pp.254-258
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    • 2019
  • Purpose: Deep inspiration breath hold (DIBH) is a well-established technique that enables efficient cardiac sparing in patients with left-sided breast cancer. The aim of the current study was to determine if DIBH is effective for reducing radiation exposure of of liver and other organs at risk in right breast radiotherapy (RT). Materials and Methods: Twenty patients with right-sided breast cancer were enrolled in this study. Three-dimensional conformal RT plans were generated for each patient, with two different computed tomography scans of free breathing (FB) and DIBH. Nodes were contoured according to the Radiation Therapy Oncology Group contouring guidelines. Dose-volume histograms for the target volume coverage and organs at risk were evaluated and analyzed. Results: DIBH plans showed significant reduction in mean liver dose (5.59 ± 2.07 Gy vs. 2.54 ± 1.40 Gy; p = 0.0003), V20Gy (148.38 ± 73.05 vs. 64.19 ± 51.07 mL; p = 0.0003) and V10Gy (195.34 ± 93.57 vs. 89.81 ± 57.28 mL; p = 0.0003) volumes compared with FB plans. Right lung doses were also significantly reduced in DIBH plans. Heart and left lung doses showed small but statistically significant improvement with application of the DIBH technique. Conclusion: We report that the use of DIBH for right-sided breast cancer significantly reduces the radiation doses to the liver, lungs, and heart.

Research on Gender Specification and Their Visual Preferences at Department Store Display Space - Target Department Store Space - (백화점 매장공간의 성별 탐색 특성과 주시경향에 관한 연구 - 백화점 매장 공간을 대상으로 -)

  • Choi, Gae-Young
    • Korean Institute of Interior Design Journal
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    • v.25 no.6
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    • pp.52-60
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    • 2016
  • Observation about space is looked steady in an instant, but in continuous movement, one's observation unconsciously stays at different points. In department store, customer actually observes around the store for buying, not focusing on certain point. By studying customer's movement and observation feature, buying desire and interest can be found. For analysis of the different searching-features according to the continuous-observation depending on sex, the study is set up to record movements of customers at women in Department store. The following are the findings. First, Men observed 0.2-0.4 units more in I-II section which are assumed as predominant. The result shows that men can focus on more section (around +0.4%) and longer (around +5.7%) than women do. Second, the same feature of observation depending on sex is that both men and women observe left and right section while keep focusing on middle section. Third, according to the fact that right-focused observation magnificently occurred in the image curved to right, the Space-composition has influenced on the observation of both men and women on the space. Forth, excessive number of display can cause avoidance of observation. Moreover, observation does not stay on the coverage due to wall or post, but is attracted to the brand name. As brand name causes right-focused observation in the image [(8)], brand name can be one of the reasons to attract observation in women apparel store. To sum up, this study is noticeable as it researches about continuous-observation. Furthermore, verifying the result that the composition of space and the placement of products can cause big differences in the observation feature is meaningful outcome.

An Exploratory Study of Industrial Security Studies for Science and Technologies Protection (제조산업 기술보호를 위한 산업보안학 메타적 분석 연구)

  • Chang, Hang-Bae
    • Journal of Advanced Navigation Technology
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    • v.17 no.1
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    • pp.123-131
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    • 2013
  • If Industrial state-of-the-art technology that made through IT convergence should be to build safely environment that can protect then IT technology and manufacturing industry become convergence and a growth engine become stable positioning. In each industry, there has been a steady effort for the industrial security. However, they introduced only managerial/technical/physical countermeasures. Therefore, it is difficult to find a reference point as industrial security necessity, protecting coverage and things and so on. It is to lack that academic research in industrial security for protecting industrial technology. In detail, a clear definition lack for industrial security. And target range classification lack for industrial security studies. In this study, we redefined the concept of industry security through previous studies. Academic classification designed industrial security studies through delphi method. we analyzed industry security trends based industrial security studies classification and presented domestic industry research orientations.