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Dosimetric Comparative Analysis of Volumetric Modulated Arc Therapy and Intensity-Modulated Radiation Therapy in Cervical Cancer
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作者 Ruixin He 《Proceedings of Anticancer Research》 2023年第3期13-17,共5页
Objective:To carry out dosimetric comparison between volumetric modulated arc therapy(VMAT)and intensity-modulated radiation therapy(IMRT)in cervical cancer.Methods:50 postoperative cervical cancer patients were inclu... Objective:To carry out dosimetric comparison between volumetric modulated arc therapy(VMAT)and intensity-modulated radiation therapy(IMRT)in cervical cancer.Methods:50 postoperative cervical cancer patients were included in this study.The patients were admitted for treatment from January 2021 to January 2022.VMAT and IMRT plans were designed for each patient to analyze the dose distribution in the target area of the two treatment techniques.Results:Comparing the monitor unit for single treatment(638.21±116.21 MU)and time of single treatment(143.21±23.14 s)in the observation group and the monitor unit for single treatment(932.14±74.11 MU)and time of single treatment(223.14±17.26 s)in the control group,there was significant difference(P<0.05);there was also significant difference(P<0.05)between the normal tissue(bladder and rectum)of the observation group and that(bladder and rectum)of the control group.Conclusion:VMAT is more effective in cervical cancer,and it has a certain protective effect on normal tissues in patients and can reduce the radiation dose. 展开更多
关键词 volumetric modulated arc therapy Intensity-modulated radiation therapy Radiotherapy for cervical cancer DOSE
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Dosimetry Comparison between Volumetric Modulated Arc Therapy with RapidArc and Fixed Field Dynamic IMRT for Local-Regionally Advanced Nasopharyngeal Carcinoma 被引量:7
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作者 Bao-min Zheng Xiao-xia Dong +3 位作者 Hao Wu You-jia Duan Shu-kui Han Yan Sun 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2011年第4期259-264,共6页
Objective: A dosimetric study was performed to evaluate the performance of volumetric modulated arc radiotherapy with RapidArc on locally advanced nasopharyngeal carcinoma (NPC). Methods: The CT scan data sets of 20 p... Objective: A dosimetric study was performed to evaluate the performance of volumetric modulated arc radiotherapy with RapidArc on locally advanced nasopharyngeal carcinoma (NPC). Methods: The CT scan data sets of 20 patients of locally advanced NPC were selected randomly. The plans were managed using volumetric modulated arc with RapidArc and fixed nine-field coplanar dynamic intensity-modulated radiotherapy (IMRT) for these patients. The dosimetry of the planning target volumes (PTV), the organs at risk (OARs) and the healthy tissue were evaluated. The dose prescription was set to 70 Gy to the primary tumor and 60 Gy to the clinical target volumes (CTV) in 33 fractions. Each fraction applied daily, five fractions per week. The monitor unit (MU) values and the delivery time were scored to evaluate the expected treatment efficiency. Results: Both techniques had reached clinical treatment’s requirement. The mean dose (Dmean), maximum dose (Dmax) and minimum dose (Dmin) in RapidArc and fixed field IMRT for PTV were 68.4±0.6 Gy, 74.8±0.9 Gy and 56.8±1.1 Gy; and 67.6±0.6 Gy, 73.8±0.4 Gy and 57.5±0.6 Gy (P<0.05), respectively. Homogeneity index was 78.85±1.29 in RapidArc and 80.34±0.54 (P<0.05) in IMRT. The conformity index (CI: 95%) was 0.78±0.01 for both techniques (P>0.05). Compared to IMRT, RapidArc allowed a reduction of Dmean to the brain stem, mandible and optic nerves of 14.1% (P<0.05), 5.6% (P<0.05) and 12.2% (P<0.05), respectively. For the healthy tissue and the whole absorbed dose, Dmean of RapidArc was reduced by 3.6% (P<0.05), and 3.7% (P<0.05), respectively. The Dmean to the parotids, the spinal cord and the lens had no statistical difference among them. The mean MU values of RapidArc and IMRT were 550 and 1,379. The mean treatment time of RapidArc and IMRT was 165 s and 447 s. Compared to IMRT, the delivery time and the MU values of RapidArc were reduced by 63% and 60%, respectively. Conclusion: For locally advanced NPC, both RapidArc and IMRT reached the clinic requirement. The target volume coverage was similar for the different techniques. The RapidArc technique showed some improvements in OARs and other tissue sparing while using reduced MUs and delivery time. 展开更多
关键词 volumetric modulated arc therapy Intensity-modulated radiotherapy DOSIMETRY Target volume Nasopharyngeal carcinoma
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Helical tomotherapy and volumetric modulated arc therapy:New therapeutic arms in the breast cancer radiotherapy 被引量:7
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作者 Olivier Lauche Youlia M Kirova +8 位作者 Pascal Fenoglietto Emilie Costa Claire Lemanski Celine Bourgier Olivier Riou David Tiberi Francois Campana Alain Fourquet David Azria 《World Journal of Radiology》 CAS 2016年第8期735-742,共8页
AIM To analyse clinical and dosimetric results of helical tomotherapy(HT) and volumetric modulated arc therapy(VMAT) in complex adjuvant breast and nodes irradiation.METHODS Seventy-three patients were included(31 HT ... AIM To analyse clinical and dosimetric results of helical tomotherapy(HT) and volumetric modulated arc therapy(VMAT) in complex adjuvant breast and nodes irradiation.METHODS Seventy-three patients were included(31 HT and 42 VMAT). Dose were 63.8 Gy(HT) and 63.2 Gy(VMAT) in the tumour bed, 52.2 Gy in the breast, 50.4 Gy in supraclavicular nodes(SCN) and internal mammary chain(IMC) with HT and 52.2 Gy and 49.3 Gy in IMC and SCN with VMAT in 29 fractions. Margins to particle tracking velocimetry were greater in the VMAT cohort(7 mm vs 5 mm).RESULTS For the HT cohort, the coverage of clinical target volumes was as follows: Tumour bed: 99.4% ± 2.4%; breast: 98.4% ± 4.3%; SCN: 99.5% ± 1.2%; IMC:96.5% ± 13.9%. For the VMAT cohort, the coverage was as follows: Tumour bed: 99.7% ± 0.5%, breast: 99.3% ± 0.7%; SCN: 99.6% ± 1.4%; IMC: 99.3% ± 3%. For ipsilateral lung, Dmean and V20 were 13.6 ± 1.2 Gy, 21.1% ± 5%(HT) and 13.6 ± 1.4 Gy, 20.1% ± 3.2%(VMAT). Dmean and V30 of the heart were 7.4 ± 1.4 Gy, 1% ± 1%(HT) and 10.3 ± 4.2 Gy, 2.5% ± 3.9%(VMAT). For controlateral breast Dmean was 3.6 ± 0.2 Gy(HT) and 4.6 ± 0.9 Gy(VMAT). Acute skin toxicity grade 3 was 5% in the two cohorts.CONCLUSION HT and VMAT in complex adjuvant breast irradiation allow a good coverage of target volumes with an acceptable acute tolerance. A longer follow-up is needed to assess the impact of low doses to healthy tissues. 展开更多
关键词 Three-dimensional conformal radiotherapy Intensity modulated radiation therapy TOXICITY Helical tomotherapy volumetric modulated arc therapy Breast cancer radiotherapy
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Partial and Full Arc Volumetric Modulated Arc Therapy in Lung Cancer Stereotactic Body Radiotherapy with Different Definitions of Internal Target Volume Based on 4D CT 被引量:2
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作者 Wu Wang Didi Chen +5 位作者 Ce Han Xiaomin Zheng Yongqiang Zhou Changfei Gong Congying Xie Xiance Jin 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第4期491-502,共12页
Purpose: To investigate the feasibility of partial arc volumetric modulated arc therapy (VMAT) in lung cancer stereotactic body radiotherapy (SBRT), as well the volumetric and dosimetric effects of different internal ... Purpose: To investigate the feasibility of partial arc volumetric modulated arc therapy (VMAT) in lung cancer stereotactic body radiotherapy (SBRT), as well the volumetric and dosimetric effects of different internal target volume (ITV) definitions with 4D CT. Methods: Fourteen patients with primary and metastatic lung cancer underwent SBRT were enrolled. Full and partial arc VMAT plans were generated with four different ITVs: ITVall, ITVMIP, ITVAIP and ITV2phases, representing ITVs generated from all 10 respiratory phases, maximum intensity projection (MIP), average intensity projection (AIP), and 2 extreme respiratory phases. Volumetric and dosimetric differences, as well as MU and delivery time were investigated. Results: Partial arc VMAT irradiated more dose at 2 cm away from planning target volume (PTV) (P = 0.002), however, it achieved better protection on mean lung dose , lung V5, spinal cord, heart and esophagus compared with full arc VMAT. The average MU and delivery time of partial arc VMAT were 240 and 1.6 min less than those of full arc VMAT. There were no significant differences on target coverage and organ at risks (OARs) sparing among four ITVs. The average percent volume differences of ITVMIP, ITVAIP and ITV2phases to ITVall were 8.6%, 13.4%, and 25.2%, respectively. Conclusions: Although partial arc VMAT delivered more dose 2 cm out of PTV, it decreases the dose to lung, spinal cord, and esophagus, as well decreased the total MU and delivery time compared with full arc VMAT without sacrificing target coverage. Partial arc VMAT was feasible and more efficient for lung SBRT. 展开更多
关键词 Lung Cancer STEREOTACTIC Body RADIOtherapy Four Dimensional COMPUTED Tomography Internal Target Volume volumetric modulated arc therapy
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A prospective trial of volumetric intensity-modulated arc therapy vs conventional intensity modulated radiation therapy in advanced head and neck cancer 被引量:2
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作者 Simon D Fung-Kee-Fung Rachel Hackett +2 位作者 Lee Hales Graham Warren Anurag K Singh 《World Journal of Clinical Oncology》 CAS 2012年第4期57-62,共6页
AIM: To prospectively compare volumetric intensitymodulated arc therapy(VMAT) and conventional intensity-modulated radiation therapy(IMRT) in coverage of planning target volumes and avoidance of multiple organs at ris... AIM: To prospectively compare volumetric intensitymodulated arc therapy(VMAT) and conventional intensity-modulated radiation therapy(IMRT) in coverage of planning target volumes and avoidance of multiple organs at risk(OARs) in patients undergoing definitive chemoradiotherapy for advanced(stage Ⅲ or Ⅳ)squamous cell cancer of the head and neck. METHODS: Computed tomography scans of 20 patients with advanced tumors of the larynx, naso-, oroand hypopharynx were prospectively planned using IMRT(7 field) and VMAT using two arcs. Calculated doses to planning target volume(PTV) and OAR were compared between IMRT and VMAT plans. Dose-volume histograms(DVH) were utilized to obtain calculated doses to PTV and OAR, including parotids, cochlea,spinal cord, brainstem, anterior tongue, pituitary and brachial plexus. DVH's for all structures were compared between IMRT and VMAT plans. In addition the planswere compared for dose conformity and homogeneity. The final treatment plan was chosen by the treating radiation oncologist. RESULTS: VMAT was chosen as the ultimate plan in 18 of 20 patients(90%) because the plans were thought to be otherwise clinically equivalent. The IMRT plan was chosen in 2 of 20 patients because the VMAT plan produced concentric irradiation of the cord which was not overcome even with an avoidance structure. For all patients, VMAT plans had a lower number of average monitor units on average(MU = 542.85) than IMRT plans(MU = 1612.58)(P < 0.001). Using the conformity index(CI), defined as the 95% isodose volume divided by the PTV, the IMRT plan was more conformal with a lower conformity index(CI = 1.61) than the VMAT plan(CI = 2.00)(P = 0.003). Dose homogeneity, as measured by average standard deviation of dose distribution over the PTV, was not different with VMAT(1.45 Gy) or IMRT(1.73 Gy)(P = 0.069). There were no differences in sparing organs at risk.CONCLUSION: In this prospective study, VMAT plans were chosen over IMRT 90% of the time. Compared to IMRT, VMAT plans used only one third of the MUs, had shorter treatment times, and similar sparing of OAR. Overall, VMAT provided similar dose homogeneity but less conformity in PTV irradiation compared to IMRT. This difference in conformity was not clinically significant. 展开更多
关键词 volumetric INTENSITY-modulated arc therapy INTENSITY-modulated radiation therapy Target COVERAGE ORGANS at risk
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A dosimetric evaluation of flattening filter-free volumetric modulated arc therapy for postoperative treatment of cervical cancer 被引量:1
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作者 Fuli Zhang Huayong Jiang +10 位作者 Weidong Xu Yadi Wang Junmao Gao Qingzhi Liu Ping Wang Na Lu Diandian Chen Bo Yao Jun Hou Heliang He Jianping Chen 《Oncology and Translational Medicine》 2016年第4期179-184,共6页
Objective The aim of the study was to compare flattening filter-free(FFF) beams and conventional flattening filter(FF) beams in volumetric modulated arc therapy(VMAT) for cervical cancer after surgery, through a retro... Objective The aim of the study was to compare flattening filter-free(FFF) beams and conventional flattening filter(FF) beams in volumetric modulated arc therapy(VMAT) for cervical cancer after surgery, through a retrospective planning study.Methods VMAT plans of FFF beams and normal FF beams were designed for a cohort of 15 patients. The prescribed dose was 45 Gy to 1.8 Gy per fraction, and at least 95% of the planning target volume received this dose. Doses were computed with a commercially available treatment planning system using a Monte Carlo(MC) algorithm. Plans were compared according to dose-volume histogram analysis in terms of planning target volume homogeneity and conformity indices(HI and CI), as well as organs at risk(OAR) dose and volume parameters. Results FFF-VMAT was similar to FF-VMAT in terms of CI, but inferior to FF-VMAT considering HI. No statistically differences were observed between FFF-VMAT and FF-VMAT in following organ at risks including pelvic bone marrow, small bowel, bladder, rectum, and normal tissue(NT)..Conclusion For patients with cervical cancer after hysterectomy, the FFF beam achieved target and OAR dose distribution similar to that of the FF beam. Reduction of beam-on time in cervical cancer is beneficial. 展开更多
关键词 flattening filter-free(FFF) cervical cancer dosimetry volumetric modulated arc therapy(VMAT)
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DICOM-RT Plan Complexity Verification for Volumetric Modulated Arc Therapy
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作者 Hideharu Miura Masao Tanooka +7 位作者 Hiroyuki Inoue Masayuki Fujiwara Kengo Kosaka Hiroshi Doi Yasuhiro Takada Soichi Odawara Norihiko Kamikonya Shozo Hirota 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2014年第3期117-124,共8页
The purpose of this study was to investigate the relationship between plan parameters verified with DICOM-RT and dosimetric results for volumetric modulated arc therapy (VMAT). We investigated three treatment location... The purpose of this study was to investigate the relationship between plan parameters verified with DICOM-RT and dosimetric results for volumetric modulated arc therapy (VMAT). We investigated three treatment locations: prostate cancer (ten cases), maxillary sinus cancer (four cases), and malignant pleura mesothelioma (four cases) with treatment plans generated by a MonacoTM treatment planning system (TPS), and delivered with an Elekta SynergyTM linear accelerator. We calculated plan parameters, including gantry and multileaf collimator (MLC) positions, Monitor Units (MU), and millimeters of MLC motion per degree of gantry rotation (mm/degree), and performed quality assurance (QA) with a DICOM-RT plan verification system. We measured the VMAT dose with a two-dimensional diode array detector. The average gamma passing rate with percent dose acceptance criteria and distance to agreement criteria of 2 mm and 2% (2 mm/2%) were 97.4%, 97.8% and 92.0% for prostate cancer, maxillary sinus cancer, and malignant pleural mesothelioma, respectively. The mean 95th percentile value for DICOM-calculated mm/degree was 4.0, 5.2, and 11.1 for prostate cancer, maxillary sinus cancer, and malignant pleural mesothelioma, respectively. The gamma passing rate showed a correlation with calculated mm/degree, with a coefficient of determination (R2) of 0.60. Higher calculated mm/degree values led to increased dosimetric errors. We conclude that dose distribution calculated by a TPS is more reliable at smaller mm/degree. 展开更多
关键词 volumetric modulated arc therapy Quality ASSURANCE RADIATION Treatment Planning RADIATION DOSIMETRY
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Dosimetric comparison of different multileaf collimators in volumetric modulated arc therapy for malignant pleural mesothelioma
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作者 Fuli Zhang Huayong Jiang +8 位作者 Weidong Xu Yadi Wang Junmao Gao Qingzhi Liu Na Lu Diandian Chen Bo Yao Jun Hou Jianping Chen 《Oncology and Translational Medicine》 CAS 2015年第4期186-189,共4页
Objective The aiom of the study was to compare the impacts of two types of multileaf collimators (MLC) [standard MLC with a width of 10 mm (sMLC) and micro-MLC with a width of 5 mm (mMLC)] on volumetric modulate... Objective The aiom of the study was to compare the impacts of two types of multileaf collimators (MLC) [standard MLC with a width of 10 mm (sMLC) and micro-MLC with a width of 5 mm (mMLC)] on volumetric modulated arc therapy (VMAT) planning for malignant pleural mesothelioma. Methods VMAT for ten patients with inoperable malignant pleural mesotheliomas was retrospectively planned with the sMLC and mMLC. Histogram-based dose-volume parameters of the planning target vol- ume (PTV) [conformity index (CI) and homogeneous index (HI)] and organs-at-risk were compared for VMAT plans with sMLC (sMLC-VMAT) and mMLC (mMLC-VMAT). Results The mMLC-VMAT plans were more efficient (average delivery time: 2.67±1.49 min) than the sMLC-VMAT plans (average delivery time: 4.21 ± 2.03 min; P 〈 0.05). Moreover, compared to the sMLC plans, the mMLC plans demonstrated advantages in the dose coverage of the PTV (CI 0.75 ± 0.08 vs 0.73± 0.09; HI 1.09 ±0.02 vs 1.10± 0.02), although the difference was not statistically significant (P 〉 0.05). In addition, significant dose sparing in the fraction of the ipsilateral lung volume receiving 〉 20 Gy (V20; 54.72± 27.08 vs 58.52 ± 29.30) and 〉 30 Gy (V30; 42.74 ± 27.86 vs 46.86± 31.49) radiation, respectively, was observed for the mMLC plans (P 〈 0.05). Conclusion Comparing sMLC-VMAT and mMLC-VMAT not only demonstrated the higher efficiency and better optimal target coverage of mMLC-VMAT, but also considerably improved the dose sparing of the ipsilateral lung in the VMAT plans for mali qnant pleural mesothelioma. 展开更多
关键词 multileaf collimator (MLC) MESOTHELIOMA volumetric modulated arc therapy (VMAT)
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Benefits and Limitations of Volumetric Modulated Arc Therapy in Treating Bilateral Breast Cancer with Regional Lymph Nodes
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作者 R. P. Srivastava K. Vandeputte C. De Wagter 《Advances in Breast Cancer Research》 2020年第4期119-126,共8页
<strong>Purpose:</strong><span style="font-family:""><span style="font-family:Verdana;"> The study was performed comparing dosimetric characteristics of volumetric modu... <strong>Purpose:</strong><span style="font-family:""><span style="font-family:Verdana;"> The study was performed comparing dosimetric characteristics of volumetric modulated arc therapy (VMAT) and field-in-field (FiF) techniques on a patient with synchronous bilateral breast carcinoma. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> The patients with bilateral breast cancer treatment were included in this study. A total dose of 40.05 Gy in 15 fractions was prescribed to the Planning Target Volume (PTV) of the whole bilateral breast cancer with the supraclavicular and infraclavicular nodes, with a complementary boost of 10 Gy in 4 fractions to the surgical bed (PTV</span><sub><span style="font-family:Verdana;">boost</span></sub><span style="font-family:Verdana;">). For both radiotherapy techniques, several V</span><sub><span style="font-family:Verdana;">xGy</span></sub><span style="font-family:Verdana;"> parameters were analyzed for the PTVs, together with the Conformity index (CI), the Homogeneity index (HI) and the critical organs at risk (OARs), lungs and heart. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> The patient was treated by the VMAT technique and the daily treatment time was less than 20 minutes with daily CBCT imaging. In the VMAT plan, the PTV 95% dose covered 38.89 ± 0.81 Gy, compared to 37.26 ± 1.02 Gy in the FiF technique. The VMAT plan improved the dose homogeneity index and lower dose in lung towards high dose region. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The study demonstrates the viability of the VMAT technique in the treatment of bilateral breast cancer. The introduced single isocentric VMAT technique is fast to deliver and it increases the dose homogeneity of the target volume with some limitations. The treatment was well tolerated, without interruption of the treatment courses caused by treatment</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">related toxicities.</span> 展开更多
关键词 Bilateral Breast Cancer (BCC) volumetric modulated arc therapy (VMAT) Field in Field (FiF) Planning Target Volume (PTV) Organ’s Volume That Receives x Gy of Dose (VxGy)
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Predicting Delivery Error Using a DICOM-RT Plan for Volumetric Modulated Arc Therapy
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作者 Hideharu Miura Masao Tanooka +6 位作者 Masayuki Fujiwara Yasuhiro Takada Hiroshi Doi Soichi Odawara Kengo Kosaka Norihiko Kamikonya Shozo Hirota 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2014年第2期82-87,共6页
The purpose of this study was to investigate the prediction of mechanical error using DICOM-RT plan parameters for volumetric modulated arc therapy (VMAT). We created plans for gantry rotation arcs of 360° and 18... The purpose of this study was to investigate the prediction of mechanical error using DICOM-RT plan parameters for volumetric modulated arc therapy (VMAT). We created plans for gantry rotation arcs of 360° and 180° (full-arc and half-arc VMAT) for six maxillary sinus cancer cases using a Monaco treatment planning system, and delivered the doses with a linear accelerator. We calculated DICOM-RT plan parameters, including gantry, multileaf collimator (MLC) positions and Monitor Units (MU). We compared plans with regard to gantry angle per MU (degrees/MU) and MLC travel per MU (mm/MU) for each segment. Calculated gantry angle/MLC position speeds and errors were evaluated by comparison with the log file. On average, the half-arc VMAT plan resulted in 47% and 35% fewer degrees/MU and mm/MU than the full-arc VMAT plan, respectively. The root mean square (r.m.s.) gantry and MLC speeds showed a linear relationship with calculated degrees/MU and mm/MU, with coefficients of determination (R2) of 0.86 and 0.72, respectively. The r.m.s. gantry angle and MLC position errors showed a linear relationship with calculated degrees/MU and mm/MU with R2 of 0.63 and 0.76, respectively. Deviations from plan parameters were related to mechanical error for VMAT, and provided quantitative information without the need for VMAT delivery. These parameters can be used in the selection of treatment planning. 展开更多
关键词 volumetric-modulated arc therapy DICOM-RT PLAN PATIENT-SPECIFIC QA RADIOtherapy Planning COMPUTER-ASSISTED
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Volumetric modulation arc radiotherapy with flattening filter-free beams compared with conventional beams for nasopharyngeal carcinoma:a feasibility study 被引量:3
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作者 Mingzan Zhuang Tuodan Zhang +5 位作者 Zhijian Chen Zhixiong Lin Derui Li Xun Peng Qingchun Qiu Renhua Wu 《Chinese Journal of Cancer》 SCIE CAS CSCD 2013年第7期397-402,共6页
There is increasing interest in the clinical use of flattening filter-free(FFF) beams.In this study,we aimed to investigate the dosimetric characteristics of volumetric modulated arc radiotherapy(VMAT) with FFF beams ... There is increasing interest in the clinical use of flattening filter-free(FFF) beams.In this study,we aimed to investigate the dosimetric characteristics of volumetric modulated arc radiotherapy(VMAT) with FFF beams for nasopharyngeal carcinoma(NPC).Ten NPC patients were randomly selected to undergo a RapidArc plan with either FFF beams(RA-FFF) or conventional beams(RA-C).The doses to the planning target volumes(PTVs),organs at risk(OARs),and normal tissues were compared.The technical delivery parameters for RapidArc plans were also assessed to compare the characteristics of FFF and conventional beams.Both techniques delivered adequate doses to PTVs.For PTVs,RA-C delivered lower maximum and mean doses and improved conformity and homogeneity compared with RA-FFF.Both techniques provided similar maximum doses to the optic nerves and lenses.For the brain stem,spinal cord,larynx,parotid glands,oral cavity,and skin,RA-FFF showed significant dose increases compared to RA-C.The dose to normal tissue was lower in RA-FFF.The monitor units(MUs) were(536 ± 46) MU for RA-FFF and(501± 25) MU for RA-C.The treatment duration did not significantly differbetween plans.Although both treatment plans could meet clinical needs,RA-C is dosimetrically superior to RA-FFF for NPC radiotherapy. 展开更多
关键词 无滤波器 鼻咽癌 无梁 放疗 剂量学特性 传统 平坦 调制
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ArcCHECK Machine QA工具在医用直线加速器质量保证中的应用效果
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作者 张上超 曾华驱 王思阳 《医疗装备》 2024年第7期19-24,共6页
目的探讨ArcCHECK Machine QA工具在医用直线加速器质量保证中的应用效果。方法利用ArcCHECK Machine QA工具和ArcCHECK体模对医用直线加速器进行性能测试,项目包括机架角度、机架旋转速度、机架旋转中心、多叶准直器和铅门位置的一致... 目的探讨ArcCHECK Machine QA工具在医用直线加速器质量保证中的应用效果。方法利用ArcCHECK Machine QA工具和ArcCHECK体模对医用直线加速器进行性能测试,项目包括机架角度、机架旋转速度、机架旋转中心、多叶准直器和铅门位置的一致性、机架旋转出束时的平坦度和对称性,评估该工具在医用直线加速器质量保证中的应用效果。结果旋转模式下机架平均旋转速度为3.6 deg/s,最大偏差约0.5 deg/s;机架旋转等中心形成的平均半径为0.4 mm,多叶准直器与铅门的最大距离正、负差异平均值分别为0.7 mm、-0.7 mm;旋转出束模式下Y方向的平坦度为1.8%,Y方向的对称性为1.1%,X方向的对称性为4.3%。结论ArcCHECK Machine QA工具可用于医用直线加速器常规及容积调强出束性能质量保证。 展开更多
关键词 arcCHECK Machine QA工具 质量保证 容积调强 等中心
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基于ArcCheck和电子射野影像装置脑瘤患者特异性容积调强放射治疗剂量验证过程容差限值与干预限值研究 被引量:2
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作者 史传磊 高峰 +1 位作者 宫瑾 邱晓光 《中国医学装备》 2023年第8期19-24,共6页
目的:基于ArcCheck和电子射野影像装置(EPID)开展脑瘤患者特异性容积调强放射治疗(VMAT)剂量验证,明确两种不同类别验证工具对脑瘤VMAT剂量验证的适用性,探索剂量验证中γ通过率容差限值(TL)和干预限值(AL),为放射治疗质量控制提供参考... 目的:基于ArcCheck和电子射野影像装置(EPID)开展脑瘤患者特异性容积调强放射治疗(VMAT)剂量验证,明确两种不同类别验证工具对脑瘤VMAT剂量验证的适用性,探索剂量验证中γ通过率容差限值(TL)和干预限值(AL),为放射治疗质量控制提供参考。方法:采用随机数表法选取在医院实施VMAT计划的180例脑瘤患者。根据病种及部位的不同将其分为30例较大靶区胶质瘤计划(X方向≥14 cm)、30例中等靶区胶质瘤计划(X方向<14 cm)、30例较小靶区室管膜瘤计划、30例生殖细胞瘤全脑计划、30例生殖细胞瘤全脑室计划、60例生殖细胞瘤小野加量计划和30例脑膜瘤计划,分别基于ArcCheck和EPID开展剂量验证,并将其分为ArcCheck组和EPID组;γ分析均设置为3%/2 mm标准、10%剂量阈值下γ通过率≥95%;对比两组验证计划γ通过率,评价剂量验证的TL和AL。结果:(1)靶区较大胶质瘤和全脑计划中ArcCheck组γ通过率分别为98.40%和98.90%,均高于EPID组,其差异有统计学意义(Z=-4.423,Z=-4.685;P<0.05),ArcCheck组TL、AL明显高于通用限值,EPID组TL、AL较通用限值差近5%;(2)靶区中等胶质瘤和全脑室计划中ArcCheck组和EPID组γ通过率分别为96.98%、97.36%和97.11%、97.60%,两组γ通过率差异无统计学意义,两组TL和AL均≥94%和>90%;(3)小靶区的室管膜瘤计划和生殖细胞瘤小野加量计划,ArcCheck组γ通过率分别为93.45%和94.06%,均低于EPID组,其差异有统计学意义(t=-9.40%,t=-9.41;P<0.05),ArcCheck组TL较通用限值差分别为6.88%和8.47%,AL较通用限值差分别为10.40%和8.76%,EPID组TL>90%、AL接近90%;(4)靶区大小不一、形状复杂的脑膜瘤中ArcCheck组和EPID组γ通过率分别为96.75%和97.05%,差异均无统计学意义,ArcCheck组TL、AL分别为89.33%和86.86%;EPID组TL、AL分别为93.17%和89.69%,更接近通用限值。结论:在靶区较大胶质瘤和全脑VMAT计划中,推荐使用ArcCheck进行剂量验证。在靶区较小室管膜瘤、生殖细胞瘤小野和脑膜瘤VMAT计划中,推荐使用EPID进行剂量验证。 展开更多
关键词 脑瘤 剂量验证 容积调强放射治疗(VMAT) 容差限值(TL) 干预限值(AL)
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A Systematic Approach to Patient-Specific Quality Assurance for Volumetric Modulated Arc Therapy
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作者 SONG Yu-lin Ceferino Obcemea +1 位作者 Boris Mueller Borys Mychalczak 《Chinese Journal of Biomedical Engineering(English Edition)》 CSCD 2015年第2期58-65,共8页
We developed the first non-commercial treatment planning system for volumetric modulated arc therapy(VMAT) in the United States. Because VMAT involves multi-parameter modulations, it is imperative to develop a compreh... We developed the first non-commercial treatment planning system for volumetric modulated arc therapy(VMAT) in the United States. Because VMAT involves multi-parameter modulations, it is imperative to develop a comprehensive, rigorous and yet, practical procedure for routine patient-specific quality assurance(QA). In this paper, we presented our own approach as being currently implemented in our institution.Our patient-specific QA procedure involves multi-levels: pre-treatment QA,on-treatment QA, and posttreatment QA. The pre-treatment QA focuses on dosimetry verification, which is done with the commercial Map CHECK in Map PHAN mounted on an isocentric mounting fixture(IMF). This method is also referred to the fixed-gantry technique,i.e., the beams always remain perpendicular to the detector plane. The on-treatment QA involves in vivo optically stimulated luminescent dosimetry(OSLD).Prior to the treatment, two nano Dot TM OSLD dosimeters are placed on the patient abdomen under 1 cm bolus at the isocenter location. The irradiated dosimeters are then read by a nano Dot TM reader and the average reading of the two is calculated. The post-treatment QA involves the analysis of the Dyna Log and DLog files. The Dyna Log is a treatment log file that contains the planned and actual leaf positions at a given gantry angle. The DLog is a treatment log file that contains the planned segmented treatment table(STT) and the corresponding segment boundary samples, i.e., the actual delivered MU and gantry angle increment at each control point. 展开更多
关键词 volumetric modulated arc therapy(VMAT) quality assurance intensity modulated radiation therapy(IMRT) rapid arc
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Long-term follow-up of volumetric modulated arc therapy in definitive radiotherapy for cervical cancer: A single-center retrospective experience
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作者 Yidi Yuan Jing You +1 位作者 Weihu Wang Xiaofan Li 《Radiation Medicine and Protection》 2020年第2期81-87,共7页
Objective:To evaluate the treatment outcomes and toxicity of volumetric modulated arc therapy(VMAT)in definitive radiotherapy for patients with cervical cancer.Methods:Medical records of 440 patients with cervical can... Objective:To evaluate the treatment outcomes and toxicity of volumetric modulated arc therapy(VMAT)in definitive radiotherapy for patients with cervical cancer.Methods:Medical records of 440 patients with cervical cancer treated with VMAT in definitive radiotherapy with or without concurrent chemotherapy between January 2010 and June 2015 in our institution were retrospectively reviewed.A dose of 45 Gy was prescribed to the planning target volume with VMAT in 25 fractions,followed by high-dose rate intracavitary brachytherapy with 28–36 Gy in 4–6 fractions.Survival time was estimated using Kaplan-Meier method.Risk factors for treatment failure were identified using Cox proportional hazards regression model.Results:The median follow-up periods were 58.3 months(range:2.7–112.9 months).The 3-and 5-year survival rates were overall survival(OS)79.4%and 74.4%,cancer-specific survival(CSS)81.4%and 77.1%,progressionfree survival(PFS)73.3%and 71.1%,locoregional control(LC)83.3%and 82%and distant metastasis-free survival(DMFS)80.8%and 77.7%,respectively.The 5-year OS for patients with different stages was IB191.6%,IB2100%,IIA 82.5%,IIB 74.4%,IIIA 57.1%,IIIB 61.7%and IVB 17.6%,respectively.Of the 124 patients with recurrence,93 patients(75.0%)experienced distant failure.Multivariate analysis showed that non-squamous cell carcinoma of the cervix(P<0.001),more advanced stage(P=0.004),pelvic lymph node metastasis(P<0.001)and para-aortic lymph node metastasis(P=0.019)were all independent risk factors of PFS.The incidence of grades 3–4 late bowel toxicities was 2.7%.No grades 3–4 bladder toxicity was observed.Conclusion:This study demonstrated that the use of VMAT in definitive radiotherapy resulted in satisfactory outcomes with acceptable toxicities for patients with cervical cancer.Distant metastasis predominated as the pattern of disease relapse.Further studies are needed to investigate the intensified systemic therapies. 展开更多
关键词 volumetric modulated arc therapy Cervical cancer Definitive radiotherapy
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Evaluation of 3D-CRT and VMAT Radiotherapy Plans for Left Breast Cancer with Regional Lymph Nodes Irradiation
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作者 Houda Benmessaoud Hasnae Bouhia +4 位作者 Halima Ahmut Sanaa El Majjaoui Hanane El Kacemi Khalid Hassouni Tayeb Kebdani 《Journal of Cancer Therapy》 2023年第8期345-352,共15页
Introduction: Radiation therapy after breast surgery is an integral part of the treatment of early breast cancer. The goal of radiation therapy is to achieve the best possible coverage of the planning target volume (P... Introduction: Radiation therapy after breast surgery is an integral part of the treatment of early breast cancer. The goal of radiation therapy is to achieve the best possible coverage of the planning target volume (PTV), while reducing the dose to organs at risk (OARs) which are normal tissues whose sensitivity to irradiation could cause damage that can lead to modification of the treatment plan. In the last decade, radiation oncologist started to use the Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) for irradiating the breast, in order to achieve better dose distribution and target dose to the PTV and OAR. The aim of this study is to compare 2 external radiotherapy techniques (VMAT vs 3D) for patients with node-positive left breast cancer. Patients and Methods: We randomly selected 10 cases of postoperative radiotherapy for breast cancer in our hospital. The patients are all female, the average age was 45.4 years old, and the primary lesions are left breast. The ANOVA test was used to compare the mean difference between subgroups, and the p value Results: Dose volume histogram (DVH) was used to analyze each evaluation dose of clinical target volume (CTV) and organs at risk (OARs). Compared to 3DCRT plans, VMAT provided more uniform coverage to the breast and regional lymph nodes. The max point dose for tVMAT was lower on average (106.4% for VMAT versus 109% for 3DCRT). OAR sparing was improved with tVMAT, with a lower average V17Gy for the left lung (27.91% for VMAT versus 30.04% for 3DCRT, p and lower for V28Gy (13.75% for VMAT versus 22.34% for 3DCRT, p = 0.01). We also found a lower V35Gy for the heart on VMAT plan (p = 0.02). On the contrary, dose of contralateral breast was lower in 3DCRT than VMAT (0.59 Gy vs 3.65 Gy, p = 0.00). Conclusion: The both types of plans can meet the clinical dosimetry demands of postoperative radiotherapy for left breast cancer. The VMAT plan has a better conformity, but 3CDRT can provide a lower dose to the contralateral organs (breast and lung) to avoid the risk of secondary cancers. 展开更多
关键词 volumetric-modulated arc therapy 3D-Conformal Radiation therapy Left Breast Cancer Target Volumes Treatment Plan
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基于美国医学物理学家协会TG119报告的TaiChi加速器质量控制体系建立研究
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作者 庞廷田 王涛 +7 位作者 雷琪琪 杨波 汪之群 张杰 陈胤竹 李世豪 昝鹏 邱杰 《中国医学装备》 2024年第6期1-5,11,共6页
目的:依据美国医学物理学家协会(AAPM)TG119号报告测试方法和项目对TaiChi加速器在RayStation治疗计划系统(简称RayStation系统)中的建模数据模型进行测试评估。方法:在治疗计划系统中按AAPM TG119号报告要求设计模拟多靶区、前列腺靶... 目的:依据美国医学物理学家协会(AAPM)TG119号报告测试方法和项目对TaiChi加速器在RayStation治疗计划系统(简称RayStation系统)中的建模数据模型进行测试评估。方法:在治疗计划系统中按AAPM TG119号报告要求设计模拟多靶区、前列腺靶区、头颈靶区、容易型C形靶区计划和困难型C形靶区计划等不同临床情况测试病例的调强放射治疗(IMRT)和容积旋转调强放射治疗(VMAT)计划,测量两种计划中点剂量和面积量偏差,并将测试结果与AAPM TG119报告中推荐的标准进行对比分析。使用IBA CC13电离室和ArcCHECK矩阵电离室分别对点剂量和面剂量进行验证,评估标准为3%/3mm的γ通过率。采用置信度评判测量剂量与计算剂量的一致性。结果:测试病例计划剂量目标、点剂量偏差及面剂量分布准确性均满足报告要求:测试病例IMRT和VMAT计划的靶区高剂量点平均剂量偏差分别为(0.39±1.02)%和(1.27±0.64)%,置信度分别为2.39%和2.52%。IMRT和VMAT计划的危及器官(OAR)低剂量点平均剂量偏差分别为(0.53±1.73)%和(0.88±1.11)%,置信度分别为3.92%和3.06%。IMRT和VMAT计划3%/3mm标准下的平均γ通过率分别为(99.52±0.366)%和(99.86±0.136)%,置信度分别为1.196%和0.406%。结论:TaiChi加速器性能和Raystation系统6MV FFF模型拟合精度满足AAPM TG119号报告标准,依据此测试结果建立后续设备和患者质控的标准,并为后续加速器性能的改进提供了参考。 展开更多
关键词 美国医学物理家协会(AAPM)TG119报告 加速器 调强放射治疗(IMRT) 容积旋转调强放射治疗(VMAT)
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D-CBCT在肺癌容积旋转调强计划精准治疗中的临床应用
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作者 成俊 徐雪峰 李伟 《中国CT和MRI杂志》 2024年第4期35-37,共3页
目的探讨椎形束CT(D-CBCT)在肺癌容积旋转调强(VMAT)计划精准治疗中的临床应用。方法选取2019年10月~2022年10月在南通市第三人民医院放射治疗科就诊的100例肺癌患者。根据CBCT扫描模式不同,分为4D组(n=57)和3D组(n=43)。比较两组患者... 目的探讨椎形束CT(D-CBCT)在肺癌容积旋转调强(VMAT)计划精准治疗中的临床应用。方法选取2019年10月~2022年10月在南通市第三人民医院放射治疗科就诊的100例肺癌患者。根据CBCT扫描模式不同,分为4D组(n=57)和3D组(n=43)。比较两组患者放疗摆位误差、内靶区(ITV)体积、靶区剂量、心脏受照剂量和肿瘤控制效果。结果在校正前后和治疗后,两组各摆位误差绝对值无统计学差异(P>0.05);4D组患者中下叶肿瘤ITV体积低于3D组(P<0.05);4D组的最大剂量(D_(max))、最小剂量(D_(min))和平均剂量(D_(mean))靶区剂量均高于3D组(P<0.05);4D组的V10、V20、V30及平均受量(D_(mean))等心脏受照剂量均低于3D组(P<0.05);4D组和3D组患者的客观有效率无明显差异(P>0.05)。结论可将D-CBCT应用于肺癌容积旋转调强计划精准治疗中,尤其采用4D-CBCT可更好提供靶区剂量,减少肺癌患者的中下叶肿瘤ITV体积和心脏受照剂量。 展开更多
关键词 椎形束CT 肺癌 容积旋转调强
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容积弧形调强放疗与静态调强放疗在宫颈癌根治性放疗中的剂量学分析
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作者 丁文秀 李树要 周绍兵 《系统医学》 2024年第16期155-158,共4页
目的 研究观察容积弧形调强放疗与静态调强放疗在宫颈癌根治性放疗中的剂量学。方法 目的选取泰兴市人民医院2018年1月—2023年12月收治的60例宫颈癌患者,根据治疗方法不同分组,每组30例,观察组进行容积弧形调强放疗,对照组进行静态调... 目的 研究观察容积弧形调强放疗与静态调强放疗在宫颈癌根治性放疗中的剂量学。方法 目的选取泰兴市人民医院2018年1月—2023年12月收治的60例宫颈癌患者,根据治疗方法不同分组,每组30例,观察组进行容积弧形调强放疗,对照组进行静态调强放疗。比较二者靶区和危及器官的剂量分布、总机器跳数和有效治疗时间。结果 观察组患者临床靶体积-计划靶体积及临床靶体积-计划靶体积的D2%、D95%、CI的受照剂量均高于对照组,而HI、D98%指标低于对照组患者;其危及器官(小肠、脊髓、直肠、股骨头)Dmean、V40及D2%的受照剂量均少于对照组患者,差异有统计学意义(P均<0.05)。观察组患者的有效治疗时间(82.35±6.34)d及总机器跳数518.34±22.33均少于对照组患者的(342.72±10.62)d及635.52±42.52,差异有统计学意义(t=115.301、13.363,P均<0.05)。结论 两种放疗方式均可达到剂量学要求,但相较于静态调强放疗,容积弧形调强放疗法计划靶区均匀性、适形度更佳,危及器官的剂量更少。 展开更多
关键词 容积弧形调强放疗 静态调强放疗 宫颈癌 剂量分布
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AAA和AXB算法在儿童髓母细胞瘤全脑全脊髓VMAT中的剂量学差异
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作者 周莉 刘悦 《医疗卫生装备》 CAS 2024年第3期56-60,共5页
目的:从剂量学角度分析各向异性算法(anisotropic analytical algorithm,AAA)和光子剂量(acuros external beam,AXB)算法在儿童髓母细胞瘤全脑全脊髓容积调强放射治疗(volumetric modulated arc therapy,VMAT)中的差异。方法:回顾性选取... 目的:从剂量学角度分析各向异性算法(anisotropic analytical algorithm,AAA)和光子剂量(acuros external beam,AXB)算法在儿童髓母细胞瘤全脑全脊髓容积调强放射治疗(volumetric modulated arc therapy,VMAT)中的差异。方法:回顾性选取2015年2月至2022年8月于某院接受全脑全脊髓放射治疗(craniospinal irradiation,CSI)的35例髓母细胞瘤患儿,采用Varian Eclipse 15.6计划系统对35例患儿分别制订AAA计划和AXB计划,分为AAA计划组和AXB计划组。比较AXB计划组与AAA计划组对计划靶区(planning target volume,PTV)D_(mean)、D2、适形性指数(conformity index,CI)、均匀性指数(homogeneity index,HI)以及危及器官(organ at risk,OAR)双侧眼球、心脏、双侧肾脏、肝脏D_(mean),双侧肺V_(5)、V_(10)、V_(20)和D_(mean),双侧晶体、双侧视神经和小肠Dmax的剂量学影响。结果:AAA计划组的CI低于AXB计划组,差异有统计学意义(P<0.05);AAA计划组的HI、D2和D_(mean)均高于AXB计划组,差异有统计学意义(P<0.05)。AAA计划组的左、右眼D_(mean)均高于AXB计划组,差异有统计学意义(P<0.05);AAA计划组的左肺V_(5)、V_(10)、D_(mean)及右肺V_(5)、V_(10)、D_(mean)均高于AXB计划组,差异有统计学意义(P<0.05)。其他OAR剂量学参数在2个计划组间的差异无统计学意义(P>0.05)。结论:相较于AAA,在CSI计划中使用AXB算法能改善靶区剂量的均匀性,有效降低因放射治疗导致的副反应发生概率,推荐在儿童髓母细胞瘤全脑全脊髓VMAT中使用AXB算法代替AAA。 展开更多
关键词 各向异性算法 光子剂量算法 儿童髓母细胞瘤 全脑全脊髓 容积调强放射治疗
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