1
|
Guo J, Zhou L, Zeng H. Research on the correction method for radiotherapy verification plans based on displaced electronic portal imaging device. J Appl Clin Med Phys 2024; 25:e14401. [PMID: 38778555 PMCID: PMC11302800 DOI: 10.1002/acm2.14401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/21/2024] [Accepted: 04/25/2024] [Indexed: 05/25/2024] Open
Abstract
BACKGROUND It has been observed that under the single isocenter conditions, the potential shifts of the electronic portal imaging devices (EPID) may be introduced when executing portal dosimetry (PD) plans for bilateral breast cancer, pleural mesothelioma, and lymphoma. These shifts are relative to the calibration positions of EPID and result in significant discrepancies in the plan verification results. PURPOSE To explore methods including correction model and specific correction matrices to revise the data obtained from displaced EPID. METHODS Two methods, the correction model and the specific correction matrices, were applied to correct the data. Five experiments were designed and conducted to build correction model and to validate the effectiveness of these two methods. Gamma passing rates were calculated and data profiles along X-axis and Y-axis were captured. RESULTS The gamma passing rates for the EPID-displaced IMRT validation plans after applying correction model, along with the application of specific correction matrices to VMAT and IMRT validation plans, exhibit results that are comparable to the cases with non-displaced EPID. Except for the VMAT plans applied correction model which showed larger discrepancies (0.041 ± 0.028, 0.049 ± 0.030), the other three exhibit minimal differences in discrepancy values. In all profiles, the corrected data from displaced EPID exhibit a high level of agreement with data obtained from non-displaced EPID. Good consistency is observed in actual application of the correction model and the specific correction matrices between gamma passing rates of data corrected and those of non-displaced data. CONCLUSIONS The proposed methods involving correction model and specific correction matrices can correct the data collected from the displaced EPID, and the gamma passing rates of the corrected data show results that are comparable to some extent with those of non-displaced data. Particularly, the results corrected by specific correction matrices closely resemble the data from non-displaced EPID.
Collapse
Affiliation(s)
- Jian Guo
- Department of Radiation OncologyThe First Affiliated Hospital of Soochow UniversitySuzhouChina
| | - Leyuan Zhou
- Department of Radiation OncologyThe Fourth Affiliated Hospital of Soochow UniversitySuzhouChina
| | - Haibin Zeng
- Department of Radiation OncologyThe Fourth Affiliated Hospital of Soochow UniversitySuzhouChina
| |
Collapse
|
2
|
Lai J, Liu S, Liu J, Li X, Chen J, Jia Y, Lei K, Zhou L. Clinical Feasibility of Using Single-isocentre Non-coplanar Volumetric Modulated Arc Therapy Combined with Non-coplanar Cone Beam Computed Tomography in Hypofractionated Stereotactic Radiotherapy for Five or Fewer Multiple Intracranial Metastases. Clin Oncol (R Coll Radiol) 2023; 35:408-416. [PMID: 37002009 DOI: 10.1016/j.clon.2023.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 01/08/2023] [Accepted: 03/16/2023] [Indexed: 03/30/2023]
Abstract
AIMS To evaluate the clinical feasibility of single-isocentre non-coplanar volumetric modulated arc therapy (NC-VMAT) with non-coplanar cone beam computed tomography (NC-CBCT) in hypofractionated stereotactic radiotherapy (HSRT) for five or fewer multiple brain metastases. MATERIALS AND METHODS Ten patients with multiple brain metastases who underwent single-isocentre NC-VMAT HSRT with limited couch rotations (within ±45°) and NC-CBCT with a limited scanning range (150-200°) were included in the current analysis. Conventional single-isocentre coplanar VMAT (C-VMAT) plans were generated and compared with NC-VMAT plans. The intracranial response and toxicities of single-isocentre NC-VMAT HSRT were also evaluated. RESULTS Compared with C-VMAT, NC-VMAT generated better target conformity (P < 0.05), a lower gradient index (P < 0.05) and better normal brain tissue sparing, especially for volume ≥12 Gy, with a median reduction of 12.65 cm3. For 45° couch rotation, NC-CBCT produced sufficient image quality to differentiate bony anatomy, even with a 150° scanning range, which could be successfully used for patient set-up correction. After NC-CBCT, 57.1% of the measured non-coplanar set-up errors exceeded the threshold value. The median gamma passing rate of NC-VMAT was higher than that of C-VMAT plans (P < 0.05). The non-coplanar beam of NC-VMAT with NC-CBCT corrections exhibited superior gamma passing rate to that without NC-CBCT corrections. The intracranial objective response rate and disease control rate for all patients were 80% (8/10) and 100% (10/10), respectively, and the most common toxicities were headache (20%) and dizziness (20%). CONCLUSION NC-VMAT with limited couch rotation (within ±45°) combined with NC-CBCT with a limited scanning range (150-200°) markedly improves the plan quality and set-up accuracy in single-isocentre multiple-target HSRT.
Collapse
|
3
|
Dosimetrical assessment of jaw tracking technique in volumetric modulated arc therapy for a sample of patients with lateralised targets. JOURNAL OF RADIOTHERAPY IN PRACTICE 2023. [DOI: 10.1017/s1460396923000031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Abstract
Introduction:
In modulated radiotherapy treatments with the jaw tracking technique (JTT), the collimator jaws can dynamically follow the multileaf collimator apertures and reduce radiation leakage. This reduction protects normal tissue from unwanted doses. Previous research has highlighted the importance of defining which patients will benefit most from JTT. Besides, some authors have expressed their concerns about possible increases in monitor units (MUs). Treatments of patients with peripheral targets and isocentre located in the patient’s midline are of particular interest. The current work assessed the effect of JTT on these cases.
Methods:
JTT plans for thirty-two patients were compared to plans with the static jaws technique. The volumes of normal tissue receiving 5 Gy (V5), 10 Gy (V10) and 20 Gy (V20), mean dose (Dmean), target coverage parameters D95, D2% and Paddick’s conformity index (PCI) were compared. MUs were also registered for comparisons. The decrease in the jaws opening with JTT was correlated to the decrease in dose values in normal tissue.
Results:
Small decreases were observed in D95 and in D2% values, without statistical significance. A 5% average decrease in PCI values was noticed as well as significant decreases in V5, V10 and Dmean values, 9% on average. A 3% decrease in V20 was also observed. The number of MUs decreased by 2%. A significant correlation was found between the reduction of the secondary collimation opening areas and the dose delivered to normal tissue.
Conclusions:
JTT technique improved normal tissue protection in volumetric modulated arc therapy treatments for the patients included in the present study.
Collapse
|
4
|
Yang H, Zhao X, He Y, Tan X, Peng H, Zhong M, Li Q, Liu X, He Y, Luo H, Jin F. Dosimetric impacts of cone-beam computed tomography (CBCT)-based anatomic changes in intensity-modulated radiotherapy for cervical cancer. ANNALS OF TRANSLATIONAL MEDICINE 2022; 10:1381. [PMID: 36660724 PMCID: PMC9843308 DOI: 10.21037/atm-22-6157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 12/19/2022] [Indexed: 01/01/2023]
Abstract
Background To evaluate the effects of dose to tumors and organs at risk (OARs) on inter-fractional anatomic changes. Methods We evaluated nine patients with cervical cancer treated with intensity-modulated radiotherapy (IMRT) (45 Gy in 25 fractions) using kV cone-beam computed tomography (CBCT) image guidance once or twice a week before treatment. For each patient, the original plan on the computed tomography (CT) image was copied to merged images, and then the fractional doses were calculated. Subsequently, deformable accumulated doses were obtained by summing the fractional absolute doses into a single dose in MIM Maestro software. The volume changes in the target and OARs were compared between the original CT and merged CBCT images, and the differences in the fractional and accumulated doses were also evaluated. Results Sixty-nine merged CBCT images were obtained and analyzed in this study. For the target areas, the volume changes in the clinical target volume (CTV) and planning target volume (PTV) reached -18.05% and -24.11% at most, respectively. The fractional D2% of the CTV and PTV was generally higher than the original plans, and the accumulated deviations were 2.27%±0.82% (P<0.01) and 2.42%±1.28% (P<0.01), respectively. The fractional D98% of the PTV was underdosed up to 18.28% for 78% of patients, and the accumulated deviations were -2.06% to -17.29% (P<0.05). For the OARs, the bladder volume changes were the most dramatic, reducing up to 93.60%. The fractional Dmean and D2cc of the bladder were generally higher than the original plans, and there were significant differences in their accumulated values (P<0.05). There was no obvious trend of rectal volume change with -69.65% to 74.20%. The rectum Dmean and D2cc of the accumulated were not significantly different from the planned dose (P>0.05). Conclusions For patients with cervical cancer, the changes in bladder and rectal volume were greater than in the target volume. Although the volume changes in the bladder and rectum had no significant effect on D98% of the CTV and PTV, they had a significant effect on their own D2cc and the D2% of the CTV and PTV. More attention should be paid to the volume changes in the bladder and rectum in clinical work.
Collapse
Affiliation(s)
- Han Yang
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Xiujuan Zhao
- Department of Gynecological Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Yang He
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Xia Tan
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Haiyan Peng
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Mingsong Zhong
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Qicheng Li
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Xianfeng Liu
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Yanan He
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Huanli Luo
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| | - Fu Jin
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing, China
| |
Collapse
|
5
|
Jiang S, Xue Y, Li M, Yang C, Zhang D, Wang Q, Wang J, Chen J, You J, Yuan Z, Wang X, Zhang X, Wang W. Artificial Intelligence-Based Automated Treatment Planning of Postmastectomy Volumetric Modulated Arc Radiotherapy. Front Oncol 2022; 12:871871. [PMID: 35547874 PMCID: PMC9084926 DOI: 10.3389/fonc.2022.871871] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 03/22/2022] [Indexed: 12/24/2022] Open
Abstract
As a useful tool, artificial intelligence has surpassed human beings in many fields. Artificial intelligence-based automated radiotherapy planning strategies have been proposed in lots of cancer sites and are the future of treatment planning. Postmastectomy radiotherapy (PMRT) decreases local recurrence probability and improves overall survival, and volumetric modulated arc therapy (VMAT) has gradually become the mainstream technique of radiotherapy. However, there are few customized effective automated treatment planning schemes for postmastectomy VMAT so far. This study investigated an artificial intelligence based automated planning using the MD Anderson Cancer Center AutoPlan (MDAP) system and Pinnacle treatment planning system (TPS), to effectively generate high-quality postmastectomy VMAT plans. In this study, 20 patients treated with PMRT were retrospectively investigated, including 10 left- and 10 right-sided postmastectomy patients. Chest wall and the supraclavicular, subclavicular, and internal mammary regions were delineated as target volume by radiation oncologists, and 50 Gy in 25 fractions was prescribed. Organs at risk including heart, spinal cord, left lung, right lung, and lungs were also contoured. All patients were planned with VMAT using 2 arcs. An optimization objective template was summarized based on the dose of clinical plans and requirements from oncologists. Several treatment planning parameters were investigated using an artificial intelligence algorithm, including collimation angle, jaw collimator mode, gantry spacing resolution (GSR), and number of start optimization times. The treatment planning parameters with the best performance or that were most preferred were applied to the automated treatment planning method. Dosimetric indexes of automated treatment plans (autoplans) and manual clinical plans were compared by the paired t-test. The jaw tracking mode, 2-degree GSR, and 3 rounds of optimization were selected in all the PMRT autoplans. Additionally, the 350- and 10-degree collimation angles were selected in the left- and right-sided PMRT autoplans, respectively. The uniformity index and conformity index of the planning target volume, mean heart dose, spinal cord D0.03cc, mean lung dose, and V5Gy and V20Gy of the lung of autoplans were significantly better compared with the manual clinical plans. An artificial intelligence-based automated treatment planning method for postmastectomy VMAT has been developed to ensure plan quality and improve clinical efficiency.
Collapse
Affiliation(s)
- Shengpeng Jiang
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Yi Xue
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Ming Li
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Chengwen Yang
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Daguang Zhang
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Qingxin Wang
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Jing Wang
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Jie Chen
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Jinqiang You
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Zhiyong Yuan
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| | - Xiaochun Wang
- Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Xiaodong Zhang
- Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Wei Wang
- Department of Radiation Ocology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Breast Cancer Prevention and Therapy, Tianjin Medical University, Ministry of Education, Tianjin, China
| |
Collapse
|
6
|
Sun W, Shi Y, Li Y, Ge C, Yang X, Xia W, Chen K, Wang L, Dong L, Wang H. Selection Strategy of Jaw Tracking in VMAT Planning for Lung SBRT. Front Oncol 2022; 12:820632. [PMID: 35211411 PMCID: PMC8860988 DOI: 10.3389/fonc.2022.820632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/17/2022] [Indexed: 11/26/2022] Open
Abstract
Purpose This study aimed to investigate the dosimetric effect and delivery reliability of jaw tracking (JT) with increasing planning target volume (PTV) for lung stereotactic body radiation therapy (SBRT) plans. A threshold of PTV was proposed as a selection criterion between JT and fixed-jaw (FJ) techniques. Methods A total of 28 patients with early-stage non-small-cell lung cancer were retrospectively included. The PTVs ranged from 4.88 cc to 68.74 cc, prescribed with 48 Gy in four fractions. Three-partial-arc volumetric modulated arc therapy (VMAT) plans with FJ and with JT were created for each patient with the same optimization objectives. These two sets of plans were compared using metrics, including conformity index (CI), V50%, R50%, D2cm, dose–volume parameters of organs at risk, and monitor units (MUs). The ratio of small subfields (<3 cm in either dimension), %SS, was acquired as a surrogate for the small-field uncertainty. Statistical analyses were performed to evaluate the correlation between the differences in these parameters and the PTV. Results The V50%, R50%, D2cm, and V20Gy, D1,500cc, and D1,000cc of the lung showed a statistically significant improvement in JT plans as opposed to FJ plans, while the number of MU in JT plans was higher by an average of 1.9%. Between FJ and JT plans, the PTV was strongly correlated with the differences in V50%, moderately correlated with those in V20Gy of the lung, and weakly correlated with those in D2cm and D1,500cc of the lung. By using JT, %SS was found to be negatively correlated with the PTV, and the PTV should be at least approximately 12.5 cc for an expected %SS <50%, which was 15 cc for a %SS <20% and 20 cc for a %SS <5%. Conclusions Considering the dosimetric differences and small-field uncertainties, JT could be selected using a PTV threshold, such as 12.5, 15, or 20 cc, on the basis of the demand of delivery reliability for lung SBRT.
Collapse
Affiliation(s)
- Wuji Sun
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| | - Yinghua Shi
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| | - Yu Li
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| | - Chao Ge
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| | - Xu Yang
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| | - Wenming Xia
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| | - Kunzhi Chen
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| | - Libo Wang
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| | - Lihua Dong
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China.,Jilin Provincial Key Laboratory of Radiation Oncology and Therapy, Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China.,National Health Commission (NHC) Key Laboratory of Radiobiology, School of Public Health, Jilin University, Changchun, China
| | - Huidong Wang
- Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China.,Jilin Provincial Key Laboratory of Radiation Oncology and Therapy, Department of Radiation Oncology and Therapy, The First Hospital of Jilin University, Changchun, China
| |
Collapse
|
7
|
Chen H, Huang Y, Wang H, Shao Y, Yue NJ, Gu H, Duan Y, Feng A, Xu Z. Dosimetric comparison and biological evaluation of fixed-jaw intensity-modulated radiation therapy for T-shaped esophageal cancer. Radiat Oncol 2021; 16:158. [PMID: 34412656 PMCID: PMC8375041 DOI: 10.1186/s13014-021-01882-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 08/11/2021] [Indexed: 12/24/2022] Open
Abstract
Background To evaluate the dosimetric and biological benefits of the fixed-jaw (FJ) intensity-modulated radiation therapy (IMRT) technique for patients with T-shaped esophageal cancer. Methods FJ IMRT plans were generated for thirty-five patients and compared with jaw tracking (JT) IMRT, static jaw (SJ) IMRT and JT volumetric modulated arc therapy (VMAT). Dosimetric parameters, tumor control probability (TCP) and normal tissue complication probability (NTCP), monitor units (MUs), delivery time and gamma passing rate, as a measure of dosimetric verification, were compared. The correlation between the length of PTV-C below the upper boundary of lung tissue (PTV-Cinferior) and dosimetric parameters and NTCP of the lung tissue were analyzed. Results The homogeneity and conformity of the target in the four plans were basically equivalent. When compared to the JT IMRT and SJ IMRT plans, FJ IMRT plan led to a statistically significant improvement in the NTCP and low-middle dosimetric parameters of the lung, and the improvement had a moderately positive correlation with the length of PTV-Cinferior, with a correlation coefficient ranging from 0.523 to 0.797; the FJ IMRT plan exhibited better lung sparing in low-dose volumes than the JT VMAT plan. The FJ IMRT plan had similar MUs (888 ± 99) and delivery times (516.1 ± 54.7 s) as the JT IMRT plan (937 ± 194, 522 ± 5.6 s) but higher than SJ IMRT (713 ± 137, 488.8 ± 45.2 s) and JT VMAT plan (517 ± 59, 263.7 ± 43.3 s). Conclusions The FJ IMRT technique is superior in reducing the low-dose volumes of lung tissues for patients with T-shaped esophageal cancer.
Collapse
Affiliation(s)
- Hua Chen
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 West Huaihai Road, Xuhui District, Shanghai, 200030, China
| | - Ying Huang
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 West Huaihai Road, Xuhui District, Shanghai, 200030, China
| | - Hao Wang
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 West Huaihai Road, Xuhui District, Shanghai, 200030, China
| | - Yan Shao
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 West Huaihai Road, Xuhui District, Shanghai, 200030, China
| | - Ning J Yue
- Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ, 08903, USA
| | - Hengle Gu
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 West Huaihai Road, Xuhui District, Shanghai, 200030, China
| | - Yanhua Duan
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 West Huaihai Road, Xuhui District, Shanghai, 200030, China
| | - Aihui Feng
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 West Huaihai Road, Xuhui District, Shanghai, 200030, China
| | - Zhiyong Xu
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, No. 241 West Huaihai Road, Xuhui District, Shanghai, 200030, China.
| |
Collapse
|
8
|
Pudsey LMM, Cutajar D, Wallace A, Saba A, Schmidt L, Bece A, Clark C, Yamada Y, Biasi G, Rosenfeld A, Poder J. The use of collimator angle optimization and jaw tracking for VMAT-based single-isocenter multiple-target stereotactic radiosurgery for up to six targets in the Varian Eclipse treatment planning system. J Appl Clin Med Phys 2021; 22:171-182. [PMID: 34288376 PMCID: PMC8425912 DOI: 10.1002/acm2.13360] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 06/30/2021] [Accepted: 07/02/2021] [Indexed: 11/06/2022] Open
Abstract
PURPOSE Island blocking occurs in single-isocenter multiple-target (SIMT) stereotactic radiotherapy (SRS) whenever targets share multi-leaf collimator (MLC) leaf pairs. This study investigated the effect on plan quality and delivery, of reducing island blocking through collimator angle optimization (CAO). In addition, the effect of jaw tracking in this context was also investigated. METHODS For CAO, an algorithm was created that selects the collimator angle resulting in the lowest level of island blocking, for each beam in any given plan. Then, four volume-modulated arc therapy (VMAT) SIMT SRS plans each were generated for 10 retrospective patients: two CAO plans, with and without jaw tracking, and two plans with manually selected collimator angles, with and without jaw tracking. Plans were then assessed and compared using typical quality assurance procedures. RESULTS There were no substantial differences between plans with and without CAO. Jaw tracking produced statistically significant reduction in low-dose level parameters; healthy brain V10% and mean dose were reduced by 9.66% and 15.58%, respectively. However, quantitative values (108 cc for V10% and 0.35 Gy for mean dose) were relatively small in relation to clinical relevance. Though there were no statistically significant changes in plan deliverability, there was a notable trend of plans with jaw tracking having lower gamma analysis pass rates. CONCLUSION These findings suggest that CAO has limited benefit in VMAT SIMT SRS of 2-6 targets when using a low-dose penalty to the healthy brain during plan optimization in Eclipse. As clinical benefits of jaw tracking were found to be minimal and plan deliverability was potentially reduced, a cautious approach would be to exclude jaw tracking in SIMT SRS plans.
Collapse
Affiliation(s)
- Lauren M M Pudsey
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
| | - Dean Cutajar
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia.,St George Hospital Cancer Care Centre, Kogarah, NSW, Australia
| | - Alex Wallace
- St George Hospital Cancer Care Centre, Kogarah, NSW, Australia
| | - Anastasia Saba
- St George Hospital Cancer Care Centre, Kogarah, NSW, Australia
| | - Laurel Schmidt
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
| | - Andrej Bece
- St George Hospital Cancer Care Centre, Kogarah, NSW, Australia
| | - Catherine Clark
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
| | - Yoshiya Yamada
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Giordano Biasi
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
| | - Anatoly Rosenfeld
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
| | - Joel Poder
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia.,St George Hospital Cancer Care Centre, Kogarah, NSW, Australia
| |
Collapse
|
9
|
Chun M, Joon An H, Kwon O, Oh DH, Park JM, Kim JI. Impact of plan parameters and modulation indices on patient-specific QA results for standard and stereotactic VMAT. Phys Med 2019; 62:83-94. [PMID: 31153402 DOI: 10.1016/j.ejmp.2019.05.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 05/03/2019] [Accepted: 05/04/2019] [Indexed: 12/30/2022] Open
Abstract
PURPOSE To demonstrate the impact of modulation indices and plan parameters on the gamma passing rates (GPR) of patient-specific quality assurance of standard and stereotactic volumetric modulated arc therapy (VMAT) plans. METHODS A total of 758 patients' QA plans were utilized, including standard VMAT plans with Trilogy (n = 87, group A) and TreuBeam STx (n = 332, group B), and 339 stereotactic VMAT plans with TrueBeam STx (group C). Modulation indices were obtained considering the speed and acceleration of the multileaf collimator (MLC) (MIs, MIa), and MLC, gantry speed, and dose rate changes (MIt). The mean aperture size (MA), monitor unit (MU), and amount of jaw tracking (%JT) were acquired. Gamma analysis was performed with 2 mm/2% and 1 mm/2% for the standard and stereotactic VMAT plans, respectively. Statistical analyses were performed to investigate the correlation between modulation index/plan parameters and GPR. RESULTS Spearman's rank correlation to GPRs with MIs, MIa, and MIt, were -0.44, -0.45, and -0.46 for group A; -0.39, -0.37, and -0.38 for group B; and -0.04, -0.11, and -0.10 for group C, respectively. While MU and MA showed significant correlations in all groups, %JT showed a significant correlation only with stereotactic VMAT plans. The most influential parameter combinations were MU-MA (rs = 0.50), MIs-%JT (rs = 0.43), and MU-%JT (rs = 0.38) for groups A, B, and C, respectively. CONCLUSIONS MLC modulation mostly affected the GPR in the delivery of standard VMAT plans, while MU and %JT showed more importance in stereotactic VMAT plans.
Collapse
Affiliation(s)
- Minsoo Chun
- Department of Radiation Oncology, Seoul National University Hospital, Seoul, Republic of Korea; Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea
| | - Hyun Joon An
- Department of Radiation Oncology, Seoul National University Hospital, Seoul, Republic of Korea; Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - Ohyun Kwon
- Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - Do Hoon Oh
- Department of Radiation Oncology, Chung-Ang University Hospital, Seoul, Republic of Korea
| | - Jong Min Park
- Department of Radiation Oncology, Seoul National University Hospital, Seoul, Republic of Korea; Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea; Center for Convergence Research on Robotics, Advanced Institutes of Convergence Technology, Suwon, Republic of Korea
| | - Jung-In Kim
- Department of Radiation Oncology, Seoul National University Hospital, Seoul, Republic of Korea; Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea.
| |
Collapse
|
10
|
Xie K, Sun H, Gao L, Lin T, Sui J, Ni X. A comparative study of identical VMAT about two adjacent targets with and without fixed-jaw technique. Radiat Oncol 2019; 14:75. [PMID: 31068187 PMCID: PMC6505249 DOI: 10.1186/s13014-019-1284-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 04/25/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The radiation transmission through the multileaf collimators is undesired in modern techniques such as volumetric modulated arc therapy (VMAT). According to identical plans, in this study, we aim to investigate the dosimetric impact of jaw tracking on the VMAT plans on two adjacent targets. METHODS Two treatment plans were designed for eight pelvic (cervical) patients with two targets using the same optimization parameters. The original plan (O-plan) used automatically selected jaw positions. In the new plan (F-plan), the jaws were fixed to block two targets in two beams. The dosimetric parameters of the two plans were compared to evaluate the improvement of dose sparing for the body volume between two targets (named interOAR) in F-VMAT. RESULTS The mean dose of interOAR reduced significantly from 654.96 ± 113.38 cGy for O-VMAT, to 490.84 ± 80.26 cGy for F-VMAT (p = 0.018). The monitor units (MUs) in the F-plans were 1.49-fold higher than that in the O-plan. The F and O-plan performed similarly in target dose homogeneity. The differences in Dmax of spinal cord, Dmax of spinal cord planning organ at risk volume, and V20, V30, and V40 of the intestine were insignificant. CONCLUSIONS VMAT plans with the fixed-jaw method can reduce the volume between two targets effectively. However, despite the plan quality, the method can only be used when the regular methods cannot reach the clinical requirements for critical organs because of additional MUs.
Collapse
Affiliation(s)
- Kai Xie
- Radiotherapy Department, Second People's Hospital of Changzhou, Nanjing Medical University, Changzhou, 213003, People's Republic of China.,Center for Medical Physics, Nanjing Medical University, Changzhou, 213003, People's Republic of China
| | - Hongfei Sun
- Radiotherapy Department, Second People's Hospital of Changzhou, Nanjing Medical University, Changzhou, 213003, People's Republic of China.,Center for Medical Physics, Nanjing Medical University, Changzhou, 213003, People's Republic of China
| | - Liugang Gao
- Radiotherapy Department, Second People's Hospital of Changzhou, Nanjing Medical University, Changzhou, 213003, People's Republic of China.,Center for Medical Physics, Nanjing Medical University, Changzhou, 213003, People's Republic of China
| | - Tao Lin
- Radiotherapy Department, Second People's Hospital of Changzhou, Nanjing Medical University, Changzhou, 213003, People's Republic of China.,Center for Medical Physics, Nanjing Medical University, Changzhou, 213003, People's Republic of China
| | - Jianfeng Sui
- Radiotherapy Department, Second People's Hospital of Changzhou, Nanjing Medical University, Changzhou, 213003, People's Republic of China.,Center for Medical Physics, Nanjing Medical University, Changzhou, 213003, People's Republic of China
| | - Xinye Ni
- Radiotherapy Department, Second People's Hospital of Changzhou, Nanjing Medical University, Changzhou, 213003, People's Republic of China. .,Center for Medical Physics, Nanjing Medical University, Changzhou, 213003, People's Republic of China.
| |
Collapse
|
11
|
Pokhrel D, Sanford L, Halfman M, Molloy J. Potential reduction of lung dose via VMAT with jaw tracking in the treatment of single-isocenter/two-lesion lung SBRT. J Appl Clin Med Phys 2019; 20:55-63. [PMID: 30955251 PMCID: PMC6523009 DOI: 10.1002/acm2.12580] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 02/09/2019] [Accepted: 03/06/2019] [Indexed: 12/14/2022] Open
Abstract
PURPOSE/OBJECTIVES Due to higher radiosensitivity, non-target normal tissue dose is a major concern in stereotactic body radiation therapy (SBRT) treatment. The aim of this report was to estimate the dosimetric impact, specifically the reduction of normal lung dose in the treatment of single-isocenter/two-lesion lung SBRT via volumetric modulated arc therapy with jaw tracking (JT-VMAT). MATERIALS/METHODS Twelve patients with two peripherally located early-stage non-small-cell-lung cancer (NSCLC) lung lesions underwent single-isocenter highly conformal non-coplanar JT-VMAT SBRT treatment in our institution. The mean isocenter to tumors distance was 5.6 ± 1.9 (range 4.3-9.5) cm. The mean combined planning target volume (PTV) was 38.7 ± 22.7 (range 5.0-80.9) cc. A single isocenter was placed between the two lesions. Doses were 54 and 50 Gy in three and five fractions, respectively. Plans were optimized in Eclipse with AcurosXB algorithm utilizing jaw tracking options for the Truebeam with a 6 MV-FFF beam and standard 120 leaf millennium multi-leaf collimators. For comparison, the JT-VMAT plans were retrospectively re-computed utilizing identical beam geometry, objectives, and planning parameters, but without jaw tracking (no JT-VMAT). Both plans were normalized to receive the same target coverage. The conformity and heterogeneity indices, intermediate-dose spillage [D2cm , R50, Gradient Index (GI), Gradient Distance (GD)], organs at risks (OAR) doses including normal lung as well as modulation factor (MF) were compared for both plans. RESULTS For similar target coverage, GI, R50, GD, as well as the normal lung V5, V10, V20, mean lung dose (MLD), and maximum dose received by 1000 cc of lungs were statistically significant. Normal lung doses were reduced by 8%-11% with JT-VMAT. Normal lung dose increased as a function of tumor distance from isocenter. For the other OAR, up to 1%-16% reduction of non-target doses were observed with JT-VMAT. The MF and beam-on time were similar for both plans, however, MF increased as a function of tumors distance, consequently, delivering higher dose to normal lungs. CONCLUSION Utilizing jaw tracking options during optimization for single-isocenter/two-lesion lung SBRT VMAT plans reduced doses to the normal lung and other OAR, reduced intermediate-dose spillage and provided superior/similar target coverage. Application of jaw tracking did not affect delivery efficiency and provided excellent plan quality with similar MF and beam-on time. Jaw tracking is recommended for future clinical SBRT plan optimization.
Collapse
Affiliation(s)
- Damodar Pokhrel
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| | - Lana Sanford
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| | - Matthew Halfman
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| | - Janelle Molloy
- Department of Radiation Medicine, Medical Physics Graduate Program, University of Kentucky, Lexington, KY, USA
| |
Collapse
|
12
|
Yao S, Zhang Y, Chen T, Zhao G, Hu Z, Lu X, Liu Y. Dosimetric Comparison Between Jaw Tracking and No Jaw Tracking in Intensity-Modulated Radiation Therapy. Technol Cancer Res Treat 2019; 18:1533033819841061. [PMID: 31014182 PMCID: PMC6488724 DOI: 10.1177/1533033819841061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
PURPOSE This article compares the dosimetric differences between jaw tracking and no jaw tracking technique in static intensity-modulated radiation therapy plans of large and small tumors. METHODS Eight plans with large tumor (nasopharyngeal carcinoma, volume range: 510.9 to 768.0 cm3) and 8 plans with small tumor (single brain metastasis, volume range: 5.3 to 9.9 cm3) treated with jaw tracking on Varian EDGE LINAC were chosen and recalculated with no jaw tracking to study the dosimetric differences. We compared the differences of organ-at-risk doses (Dmax, Dmean), monitor units, and γ passing rate of plan verification (3mm/3%, threshold 10%; 2mm/2%, threshold 10%) between the 2 techniques. RESULTS The organ-at-risk doses of nasopharyngeal carcinoma cases having jaw tracking are all less than those with no jaw tracking. The Dmax and Dmean of organ-at-risks reduced 0.61% to 17.65% and 2.17% to 19.32%, P < .05, respectively. In cases with single brain metastasis, the organ-at-risk doses with jaw tracking were also lower than no jaw tracking. The Dmax and Dmean of organ-at-risk doses reduced 0.84% to 1.52% and 0.90% to 1.86%, P < .05, respectively. The monitor units for the large tumor and small tumor were increased by 2.41% and 1.1%, respectively. The γ passing rates (3mm/3%, th10%; 2mm/2%, th10%) of nasopharyngeal carcinoma plans are 99.89% ± 0.06% (jaw tracking) versus 99.56% ± 0.19% (no jaw tracking; P = .127); 97.15% ± 0.98% (jaw tracking) versus 91.90% ± 1.40% (no jaw tracking; P = .000), and the γ passing rates (3mm/3%, th10%; 2mm/2%, th10%) of brain metastasis plans are 99.97% ± 0.05% (jaw tracking) versus 99.44% ± 1.24% (no jaw tracking; P = .251), 98.65% ± 1.27% (jaw tracking) versus 93.35% ± 2.72% (no jaw tracking; P = .000). CONCLUSION Jaw tracking can reduce the dose of organ-at-risks compared to no jaw tracking, and the effect is more significant for plans with large tumor. The γ passing rate of plans with jaw tracking is also higher than the plans with no jaw tracking. Although the monitor units in plans of jaw tracking will increase slightly, it is recommended to use jaw tracking in static intensity-modulated radiation therapy both in large and in small tumors.
Collapse
Affiliation(s)
- Shengyu Yao
- 1 Department Radiation Oncology, Shanghai General Hospital, Shanghai, China
| | - Yin Zhang
- 2 Department Radiation Oncology, Cancer Institute of New Jersey, NJ, USA
| | - Tingfeng Chen
- 1 Department Radiation Oncology, Shanghai General Hospital, Shanghai, China
| | - Guoqi Zhao
- 1 Department Radiation Oncology, Shanghai General Hospital, Shanghai, China
| | - Zhekai Hu
- 1 Department Radiation Oncology, Shanghai General Hospital, Shanghai, China
| | - Xiaokai Lu
- 3 Department Radiation Oncology, Guiyang First People's Hospital, Guizhou, China
| | - Yong Liu
- 1 Department Radiation Oncology, Shanghai General Hospital, Shanghai, China
| |
Collapse
|
13
|
Dosimetric superiority of IMRT with jaw tracking technique for whole esophagus and T-shaped field radiotherapy in advanced esophageal cancer. PLoS One 2018; 13:e0202628. [PMID: 30183753 PMCID: PMC6124760 DOI: 10.1371/journal.pone.0202628] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 08/07/2018] [Indexed: 12/25/2022] Open
Abstract
Purpose For whole esophagus and T-shaped field radiotherapy using intensity modulated radiotherapy (IMRT) technique in advanced esophageal cancer, lower absorbed doses to lung and heart remains a challenge. The aim of this study was to investigate the dosimetric superiority in IMRT plans with jaw tracking technique for whole esophagus radiotherapy. Methods and materials Thirty-two patients with esophageal cancer were subjected to IMRT treatment plans using Eclipse treatment planning system. For every patient, four different plans were generated with six gantry angles: six large fields IMRT plans with fixed jaw (6F-IMRT), six large fields IMRT plans with jaw tracking technique (6F-IMRT-T), twelve small fields IMRT plans with fixed jaw (12F-IMRT), and twelve small fields IMRT plans with jaw tracking technique (12F-IMRT-T). Dosimetric evaluation was assessed for all plans. Results For every technique, there were no differences in planning target volume (PTV) coverage and conformity. 6F-IMRT-T plans could significantly reduce lung irradiation with 7.9% (P<0.001) reduction in V5lung and 2.5% (P<0.001) reduction in V20 lung respectively compared to 6F-IMRT plans. 12F-IMRT-T plans resulted in superior plans compared to 12-IMRT plans with a reduction of 2.9% (P<0.001) in V5lung and 0.9% (P<0.001) in V20 lung, respectively. For heart irradiation, 6F-IMRT-T and 12F-IMRT-T plans were slightly superior to 6F-IMRT and 12-IMRT plans respectively with a reduction of 1.1 Gy and 0.5 Gy in the respective mean doses. Conclusions By the use of jaw tracking technique, the IMRT plans resulted in further lung and heart sparing compared to fixed jaw plans for radiotherapy in esophageal cancer.
Collapse
|
14
|
Huang Y, Yue H, Wang M, Li S, Zhang J, Liu Z, Zhang Y. Fully automated searching for the optimal VMAT jaw settings based on Eclipse Scripting Application Programming Interface (ESAPI) and RapidPlan knowledge-based planning. J Appl Clin Med Phys 2018; 19:177-182. [PMID: 29577614 PMCID: PMC5978713 DOI: 10.1002/acm2.12313] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Revised: 01/25/2018] [Accepted: 02/21/2018] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Eclipse treatment planning system has not been able to optimize the jaw positions for Volumetric Modulated Arc Therapy (VMAT). The arbitrary and planner-dependent jaw placements define the maximum field size within which multi-leaf-collimator (MLC) sequences can be optimized to modulate the beam. Considering the mechanical constraints of MLC transitional speed and range, suboptimal X jaw settings may impede the optimization or undermine the deliverability. This work searches optimal VMAT jaw settings automatically based on Eclipse Scripting Application Programming Interface (ESAPI) and RapidPlan knowledge-based planning. METHODS AND MATERIALS Using an ESAPI script, the X jaws of rectal VMAT plans were initially set to conform the planning-target-volume (PTV), and were gradually extended toward the isocenter (PTV center) in 5-7 mm increments. Using these jaw pairs, 592 plans were automatically created for 10 patients and quantitatively evaluated using a comprehensive scoring function. A published RapidPlan model was evoked by ESAPI to generate patient-specific optimization objectives without manual intervention. All candidate plans were first stored as text files to save storage space, and only the best, worst, and conformal plans were consequently recreated for comparison. RESULTS Although RapidPlan estimates dose-volume histogram (DVH) based on individual anatomy, the geometry-based expected dose (GED) algorithm does not recognize different jaw settings but uses PTV-conformal jaws as default; hence, identical DVHs were observed regardless of planner-defined jaws. Therefore, ESAPI finalized dose-volume calculation and eliminated the plans with unacceptable hotspots before comparison. The plan quality varied dramatically with different jaw settings. Trade-offs among different organs-at-risk (OARs) were collectively considered by the proposed scoring method, which identified the best and worst plans correctly. The plans using conformal jaws were neither the best nor the worst of all candidates. CONCLUSIONS VMAT plans using optimal jaw locations can be created automatically using ESAPI and RapidPlan. Conformal jaws are not the optimal choice.
Collapse
Affiliation(s)
- Yuliang Huang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing)Department of Radiation OncologyPeking University Cancer Hospital & InstituteBeijing Cancer Hospital & Institute BeijingBeijingChina
| | - Haizhen Yue
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing)Department of Radiation OncologyPeking University Cancer Hospital & InstituteBeijing Cancer Hospital & Institute BeijingBeijingChina
| | - Meijiao Wang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing)Department of Radiation OncologyPeking University Cancer Hospital & InstituteBeijing Cancer Hospital & Institute BeijingBeijingChina
| | - Sha Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing)Department of Radiation OncologyPeking University Cancer Hospital & InstituteBeijing Cancer Hospital & Institute BeijingBeijingChina
- Department of Medical PhysicsSchool of Foundational Education & Institute of Medical HumanitiesPeking University Health Science CenterBeijingChina
| | - Jian Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing)Department of Radiation OncologyPeking University Cancer Hospital & InstituteBeijing Cancer Hospital & Institute BeijingBeijingChina
| | - Zhuolun Liu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing)Department of Radiation OncologyPeking University Cancer Hospital & InstituteBeijing Cancer Hospital & Institute BeijingBeijingChina
| | - Yibao Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing)Department of Radiation OncologyPeking University Cancer Hospital & InstituteBeijing Cancer Hospital & Institute BeijingBeijingChina
- Beijing City Key Lab for Medical Physics and EngineeringInstitute of Heavy Ion PhysicsSchool of PhysicsPeking UniversityBeijingChina
| |
Collapse
|