1
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Mirzavand Boroujeni N, Richard JPP, Sterling D, Wilke C. A linear optimization model for high dose rate brachytherapy using a novel distance metric. Phys Med Biol 2023; 68:175018. [PMID: 37489861 DOI: 10.1088/1361-6560/acea55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 07/25/2023] [Indexed: 07/26/2023]
Abstract
Purpose.We propose a linear network-based optimization model (LNBM) for high dose rate brachytherapy (HDR-BT) that uses a novel distance metric to measure the discrepancy between the dose delivered and the prescription. Unlike models in the literature, LNBM takes advantage of the adjacency structure of the patients' voxels by formalizing them into a network.Methods.We apply LNBM to a set of 7 cervical cancer cases treated with HDR-BT. State-of-the-art commercial optimization software solves LNBM to global optimality. The results of LNBM are compared with those of inverse planning by simulated annealing (IPSA) based on tumor coverage, dosimetric indices for the critical organs at risk (OARs), isodose contour plots, and two metrics of homogeneity new to this work (hot-spots volumes and diameters).Results.LNBM produces plans with improved tumor coverage and with improved isodose contour plots and dosimetric indices for OARs that receive highest dose (bladder and rectum in this study) when compared with IPSA. Using new metrics of homogeneity, we also demonstrate that LNBM produces more homogeneous plans on these cases. An analysis of the solutions of LNBM shows that they use a significant part of the voxel network structure, providing evidence that the plans produced are different from those created using traditional penalty approaches and are more directly guided by the geometry of the patients' anatomy.Conclusions.The proposed linear network-based optimization model efficiently generates more homogeneous high quality treatment plans for HDR-BT.
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Affiliation(s)
- Nasim Mirzavand Boroujeni
- Department of Industrial and Systems Engineering, University of Minnesota, 100 Union Street SE, Minneapolis, MN 55455, United States of America
| | - Jean-Philippe P Richard
- Department of Industrial and Systems Engineering, University of Minnesota, 100 Union Street SE, Minneapolis, MN 55455, United States of America
| | - David Sterling
- Department of Radiation Oncology, University of Minnesota, 516 Delaware Street SE, Minneapolis MN, 55455, United States of America
| | - Christopher Wilke
- Department of Radiation Oncology, University of Minnesota, 516 Delaware Street SE, Minneapolis MN, 55455, United States of America
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Antaki M, Renaud MA, Morcos M, Seuntjens J, Enger SA. Applying the column generation method to the intensity modulated high dose rate brachytherapy inverse planning problem. Phys Med Biol 2023; 68. [PMID: 36791469 DOI: 10.1088/1361-6560/acbc63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/15/2023] [Indexed: 02/17/2023]
Abstract
Objective.Intensity modulated high dose rate brachytherapy (IMBT) is a rapidly developing application of brachytherapy where anisotropic dose distributions can be produced at each source dwell position. This technique is made possible by placing rotating metallic shields inside brachytherapy needles or catheters. By dynamically directing the radiation towards the tumours and away from the healthy tissues, a more conformal dose distribution can be obtained. The resulting treatment planning involves optimizing dwell position and shield angle (DPSA). The aim of this study was to investigate the column generation method for IMBT treatment plan optimization.Approach.A column generation optimization algorithm was developed to optimize the dwell times and shield angles. A retrospective study was performed on 10 prostate cases using RapidBrachyMCTPS. At every iteration, the plan was optimized with the chosen DPSA which would best improve the cost function that was added to the plan. The optimization process was stopped when the remaining DPSAs would not add value to the plan to limit the plan complexity.Main results.The average number of DPSAs and voxels were 2270 and 7997, respectively. The column generation approach yielded near-optimal treatment plans by using only 11% of available DPSAs on average in ten prostate cases. The coverage and organs at risk constraints passed in all ten cases.Significance.The column generation method produced high-quality deliverable prostate IMBT plans. The treatment plan quality reached a plateau, where adding more DPSAs had a minimal effect on dose volume histogram parameters. The iterative nature of the column generation method allows early termination of the treatment plan creation process as soon as the dosimetric indices from dose volume histogram satisfy the clinical requirements or if their values stabilize.
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Affiliation(s)
- Majd Antaki
- Medical Physics Unit, Department of Oncology, McGill University, Montreal, Quebec, H4A 3J1, Canada
| | - Marc-André Renaud
- Polytechnique Montréal, Department of Mathematical and Industrial Engineering, Montreal, Canada
| | - Marc Morcos
- Medical Physics Unit, Department of Oncology, McGill University, Montreal, Quebec, H4A 3J1, Canada.,Department of Radiation Oncology, Miami Cancer Institute, Miami, FL, United States of America.,Herbert Wertheim College of Medicine, Florida International University, Miami, FL, United States of America
| | - Jan Seuntjens
- Medical Physics Unit, Department of Oncology, McGill University, Montreal, Quebec, H4A 3J1, Canada
| | - Shirin A Enger
- Medical Physics Unit, Department of Oncology, McGill University, Montreal, Quebec, H4A 3J1, Canada.,Research Institute of the McGill University Health Centre, Montreal, Quebec, H3H 2L9, Canada.,Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, H3T 1E2, Canada
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3
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Morén B, Antaki M, Famulari G, Morcos M, Larsson T, Enger SA, Tedgren ÅC. Dosimetric impact of a robust optimization approach to mitigate effects from rotational uncertainty in prostate intensity-modulated brachytherapy. Med Phys 2023; 50:1029-1043. [PMID: 36478226 DOI: 10.1002/mp.16134] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 10/17/2022] [Accepted: 11/01/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Intensity-modulated brachytherapy (IMBT) is an emerging technology for cancer treatment, in which radiation sources are shielded to shape the dose distribution. The rotatable shields provide an additional degree of freedom, but also introduce an additional, directional, type of uncertainty, compared to conventional high-dose-rate brachytherapy (HDR BT). PURPOSE We propose and evaluate a robust optimization approach to mitigate the effects of rotational uncertainty in the shields with respect to planning criteria. METHODS A previously suggested prototype for platinum-shielded prostate 169 Yb-based dynamic IMBT is considered. We study a retrospective patient data set (anatomical contours and catheter placement) from two clinics, consisting of six patients that had previously undergone conventional 192 Ir HDR BT treatment. The Monte Carlo-based treatment planning software RapidBrachyMCTPS is used for dose calculations. In our computational experiments, we investigate systematic rotational shield errors of ±10° and ±20°, and the same systematic error is applied to all dwell positions in each scenario. This gives us three scenarios, one nominal and two with errors. The robust optimization approach finds a compromise between the average and worst-case scenario outcomes. RESULTS We compare dose plans obtained from standard models and their robust counterparts. With dwell times obtained from a linear penalty model (LPM), for 10° errors, the dose to urethra ( D 0.1 c c $D_{0.1cc}$ ) and rectum ( D 0.1 c c $D_{0.1cc}$ and D 1 c c $D_{1cc}$ ) increase with up to 5% and 7%, respectively, in the worst-case scenario, while with the robust counterpart, the corresponding increases were 3% and 3%. For all patients and all evaluated criteria, the worst-case scenario outcome with the robust approach had lower deviation compared to the standard model, without compromising target coverage. We also evaluated shield errors up to 20° and while the deviations increased to a large extent with the standard models, the robust models were capable of handling even such large errors. CONCLUSIONS We conclude that robust optimization can be used to mitigate the effects from rotational uncertainty and to ensure the treatment plan quality of IMBT.
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Affiliation(s)
- Björn Morén
- Department of Mathematics, Linköping University, Linköping, Sweden
| | - Majd Antaki
- Department of Oncology, Medical Physics Unit, McGill University, Montreal, QC, Canada
| | - Gabriel Famulari
- Department of Oncology, Medical Physics Unit, McGill University, Montreal, QC, Canada.,Département de Radio-oncologie, Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada
| | - Marc Morcos
- Department of Oncology, Medical Physics Unit, McGill University, Montreal, QC, Canada
| | - Torbjörn Larsson
- Department of Mathematics, Linköping University, Linköping, Sweden
| | - Shirin A Enger
- Department of Oncology, Medical Physics Unit, McGill University, Montreal, QC, Canada.,Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC, Canada
| | - Åsa Carlsson Tedgren
- Radiation Physics, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden.,Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden.,Department of Oncology Pathology, Karolinska Institute, Stockholm, Sweden
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Wu X, Brezovich IA, Shen S, Covington E, Stanley D, Popple R. Incorporating Treatment Time into Butterfly Optimization to Reduce Total Treatment Time for Vaginal Cylinder Brachytherapy. Cureus 2022; 14:e23893. [PMID: 35530902 PMCID: PMC9076060 DOI: 10.7759/cureus.23893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/06/2022] [Indexed: 11/29/2022] Open
Abstract
Purpose For patient comfort and safety, irradiation times should be kept at a minimum while maintaining high treatment quality. In this study of high dose rate (HDR) therapy with a vaginal cylinder, we used the butterfly optimization algorithm (BOA) to simultaneously optimize individual dwell times for precise dose conformity and for the reduction of total dwell time. Material and methods BOA is a population-based, meta-heuristic algorithm that averts local minima by conducting intensive local and global searching based on switching probability. We constructed an objective function (a stimulus intensity function) that consisted of two components. The first one was the root-mean-squared dose error (RMSE) defined as the square root of the sum of squared differences between the prescribed and delivered dose at the constraint points. The second component was weighted total treatment time. Eight previously treated cases were retrospectively reviewed by re-optimizing the clinical treatment plans with BOA. Results Compared to the eight original plans generated with the commercial adaptive volume optimization algorithm (AVOA), the BOA-optimized plans reduced treatment times by 5.4% to 8.9%, corresponding to a time-saving of 13.1 to 47.7 seconds with the activities on the treatment day and saving from 29.3 to 64.6 seconds if treated with an activity of 5 CI. Dose deviations from the prescription were smaller than in the original plans. Conclusion Dose optimizations based on the BOA algorithm yield closer dose conformity in vaginal HDR treatment than AVOA. Incorporating total treatment time into the optimization algorithm reduces the delivery time while having only a small effect on dose conformity.
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Jia X, Cunha JAM, Rong Y. Artificial intelligence can overcome challenges in brachytherapy treatment planning. J Appl Clin Med Phys 2022; 23:e13504. [PMID: 35041263 PMCID: PMC8803284 DOI: 10.1002/acm2.13504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 03/12/2021] [Indexed: 11/06/2022] Open
Affiliation(s)
- Xun Jia
- Department of Radiation OncologyUniversity of Texas‐SouthwesternDallasTexasUSA
| | - J. Adam M. Cunha
- Department of Radiation OncologyUniversity of California San FranciscoSan FranciscoCaliforniaUSA
| | - Yi Rong
- Department of Radiation OncologyMayo Clinic ArizonaPhoenixArizonaUSA
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Kallis K, Mayadev J, Covele B, Brown D, Scanderbeg D, Simon A, Frisbie-Firsching H, Yashar CM, Einck JP, Mell LK, Moore KL, Meyers SM. Evaluation of dose differences between intracavitary applicators for cervical brachytherapy using knowledge-based models. Brachytherapy 2021; 20:1323-1333. [PMID: 34607771 DOI: 10.1016/j.brachy.2021.08.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 08/12/2021] [Accepted: 08/14/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE Currently, there is a lack of patient-specific tools to guide brachytherapy planning and applicator choice for cervical cancer. The purpose of this study is to evaluate the accuracy of organ-at-risk (OAR) dose predictions using knowledge-based intracavitary models, and the use of these models and clinical data to determine the dosimetric differences of tandem-and-ring (T&R) and tandem-and-ovoids (T&O) applicators. MATERIALS AND METHODS Knowledge-based models, which predict organ D2cc, were trained on 77/75 cases and validated on 32/38 for T&R/T&O applicators. Model performance was quantified using ΔD2cc=D2cc,actual-D2cc,predicted, with standard deviation (σ(ΔD2cc)) representing precision. Model-predicted applicator dose differences were determined by applying T&O models to T&R cases, and vice versa, and compared to clinically-achieved D2cc differences. Applicator differences were assessed using a Student's t-test (p < 0.05 significant). RESULTS Validation T&O/T&R model precision was 0.65/0.55 Gy, 0.55/0.38 Gy, and 0.43/0.60 Gy for bladder, rectum and sigmoid, respectively, and similar to training. When applying T&O/T&R models to T&R/T&O cases, bladder, rectum and sigmoid D2cc values in EQD2 were on average 5.69/2.62 Gy, 7.31/6.15 Gy and 3.65/0.69 Gy lower for T&R, with similar HRCTV volume and coverage. Clinical data also showed lower T&R OAR doses, with mean EQD2 D2cc deviations of 0.61 Gy, 7.96 Gy (p < 0.01) and 5.86 Gy (p < 0.01) for bladder, rectum and sigmoid. CONCLUSIONS Accurate knowledge-based dose prediction models were developed for two common intracavitary applicators. These models could be beneficial for standardizing and improving the quality of brachytherapy plans. Both models and clinical data suggest that significant OAR sparing can be achieved with T&R over T&O applicators, particularly for the rectum.
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Affiliation(s)
- Karoline Kallis
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Jyoti Mayadev
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Brent Covele
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Derek Brown
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Daniel Scanderbeg
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Aaron Simon
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Helena Frisbie-Firsching
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Catheryn M Yashar
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - John P Einck
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Loren K Mell
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Kevin L Moore
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA
| | - Sandra M Meyers
- Department of Radiation Medicine and Applied Sciences, University of California San Diego, San Diego, CA.
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Zhang R, Yang Z, Jiang S, Yu X, Qi E, Zhou Z, Zhang G. An inverse planning simulated annealing algorithm with adaptive weight adjustment for LDR pancreatic brachytherapy. Int J Comput Assist Radiol Surg 2021; 17:601-608. [PMID: 34455536 DOI: 10.1007/s11548-021-02483-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 08/10/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE The inverse planning simulated annealing (IPSA) algorithm has shown good results in cancer surgical treatment planning. However, an adaptive approach has not well been proposed for different shapes and sizes of tumors. The purpose of this study was to propose an adaptive, efficient and safe algorithm to get high-quality treatment dose planning, which is presented for pancreatic cancer. METHODS An algorithm employs an optimized IPSA and an adaptive process for adjusting the weight of organs at risk (OAR) and tumor. The algorithm, which was combined with ant colony optimization, was further optimized to reduce the number of needles. It could meet the clinical dose objectives within the tumors, reduce the dose distribution within the OAR and minimize the number of needles. Ten clinical cases were chosen randomly from patients, previously successfully treated in clinic to test our method. The algorithm was validated against clinical cases, using clinically relevant dose parameters. RESULTS The results were compared with clinical results in ten cases, indicating that the dose distribution within the tumor meets the clinical dose objectives. The dose received by OAR had been greatly reduced, and the number of needles could be reduced by about 50%. It was a significant improvement over the clinical treatment planning. CONCLUSIONS In this paper, we have devised an algorithm to optimize the treatment planning in brachytherapy. The method in this paper could meet the clinical dose objectives and reduce the difficulty of operation. The results were clinically acceptable. This algorithm is also applicable to other cancers such as lung cancer.
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Affiliation(s)
- Ruijin Zhang
- School of Mechanical Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
| | - Zhiyong Yang
- School of Mechanical Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
| | - Shan Jiang
- School of Mechanical Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China.
| | - Xiaoling Yu
- Department of Interventional Ultrasound, the First Medical Centre, Chinese PLA General Hospital, Beijing, 100853, China
| | - Erpeng Qi
- Department of Interventional Ultrasound, the First Medical Centre, Chinese PLA General Hospital, Beijing, 100853, China
| | - Zeyang Zhou
- School of Mechanical Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
| | - Guobin Zhang
- School of Mechanical Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
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Morén B, Larsson T, Tedgren ÅC. Optimization in treatment planning of high dose-rate brachytherapy - Review and analysis of mathematical models. Med Phys 2021; 48:2057-2082. [PMID: 33576027 DOI: 10.1002/mp.14762] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 11/12/2020] [Accepted: 01/22/2021] [Indexed: 12/12/2022] Open
Abstract
Treatment planning in high dose-rate brachytherapy has traditionally been conducted with manual forward planning, but inverse planning is today increasingly used in clinical practice. There is a large variety of proposed optimization models and algorithms to model and solve the treatment planning problem. Two major parts of inverse treatment planning for which mathematical optimization can be used are the decisions about catheter placement and dwell time distributions. Both these problems as well as integrated approaches are included in this review. The proposed models include linear penalty models, dose-volume models, mean-tail dose models, quadratic penalty models, radiobiological models, and multiobjective models. The aim of this survey is twofold: (i) to give a broad overview over mathematical optimization models used for treatment planning of brachytherapy and (ii) to provide mathematical analyses and comparisons between models. New technologies for brachytherapy treatments and methods for treatment planning are also discussed. Of particular interest for future research is a thorough comparison between optimization models and algorithms on the same dataset, and clinical validation of proposed optimization approaches with respect to patient outcome.
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Affiliation(s)
- Björn Morén
- Department of Mathematics, Linköping University, Linköping, Sweden
| | - Torbjörn Larsson
- Department of Mathematics, Linköping University, Linköping, Sweden
| | - Åsa Carlsson Tedgren
- Radiation Physics, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden.,Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden.,Department of Oncology Pathology, Karolinska Institute, Stockholm, Sweden
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Antaki M, L Deufel C, Enger SA. Fast mixed integer optimization (FMIO) for high dose rate brachytherapy. ACTA ACUST UNITED AC 2020; 65:215005. [DOI: 10.1088/1361-6560/aba317] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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10
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Maree SC, Bosman PAN, van Wieringen N, Niatsetski Y, Pieters BR, Bel A, Alderliesten T. Automatic bi-objective parameter tuning for inverse planning of high-dose-rate prostate brachytherapy. ACTA ACUST UNITED AC 2020; 65:075009. [DOI: 10.1088/1361-6560/ab7362] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Morén B, Larsson T, Tedgren ÅC. A mathematical optimization model for spatial adjustments of dose distributions in high dose-rate brachytherapy. ACTA ACUST UNITED AC 2019; 64:225012. [DOI: 10.1088/1361-6560/ab4d8d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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12
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Luong NH, Alderliesten T, Pieters BR, Bel A, Niatsetski Y, Bosman PA. Fast and insightful bi-objective optimization for prostate cancer treatment planning with high-dose-rate brachytherapy. Appl Soft Comput 2019. [DOI: 10.1016/j.asoc.2019.105681] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Bouter A, Alderliesten T, Pieters BR, Bel A, Niatsetski Y, Bosman PAN. GPU‐accelerated bi‐objective treatment planning for prostate high‐dose‐rate brachytherapy. Med Phys 2019; 46:3776-3787. [DOI: 10.1002/mp.13681] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/22/2019] [Accepted: 06/07/2019] [Indexed: 11/06/2022] Open
Affiliation(s)
- Anton Bouter
- Centrum Wiskunde & Informatica Science Park 123 1098 XG Amsterdam The Netherlands
| | - Tanja Alderliesten
- Department of Radiation Oncology Amsterdam UMC University of Amsterdam Meibergdreef 9 1105 AZ Amsterdam The Netherlands
| | - Bradley R. Pieters
- Department of Radiation Oncology Amsterdam UMC University of Amsterdam Meibergdreef 9 1105 AZ Amsterdam The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology Amsterdam UMC University of Amsterdam Meibergdreef 9 1105 AZ Amsterdam The Netherlands
| | | | - Peter A. N. Bosman
- Centrum Wiskunde & Informatica Science Park 123 1098 XG Amsterdam The Netherlands
- Delft University of Technology Van Mourik Broekmanweg 6 2628 XE Delft The Netherlands
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Evaluation of bi-objective treatment planning for high-dose-rate prostate brachytherapy—A retrospective observer study. Brachytherapy 2019; 18:396-403. [DOI: 10.1016/j.brachy.2018.12.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 11/08/2018] [Accepted: 12/28/2018] [Indexed: 10/27/2022]
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15
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Morén B, Larsson T, Carlsson Tedgren Å. Mathematical optimization of high dose-rate brachytherapy—derivation of a linear penalty model from a dose-volume model. ACTA ACUST UNITED AC 2018; 63:065011. [DOI: 10.1088/1361-6560/aaab83] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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16
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Guthier CV, Damato AL, Viswanathan AN, Hesser JW, Cormack RA. A fast multitarget inverse treatment planning strategy optimizing dosimetric measures for high-dose-rate (HDR) brachytherapy. Med Phys 2017. [DOI: 10.1002/mp.12410] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Christian V. Guthier
- Department of Radiation Oncology; Brigham and Womens Hospital and Dana-Faber Cancer Institute; Boston MA 02215 USA
- Harvard Medical School; Boston MA 02215 USA
| | - Antonio L. Damato
- Department of Radiation Oncology; Brigham and Womens Hospital and Dana-Faber Cancer Institute; Boston MA 02215 USA
- Harvard Medical School; Boston MA 02215 USA
| | - Akila N. Viswanathan
- Department of Radiation Oncology; Brigham and Womens Hospital and Dana-Faber Cancer Institute; Boston MA 02215 USA
- Harvard Medical School; Boston MA 02215 USA
| | - Juergen W. Hesser
- Department of Experimental Radiation Oncology; Medical Faculty of Mannheim, Heidelberg University; 68167 Mannheim Germany
- IWR, Heidelberg University; 69126 Heidelberg Germany
| | - Robert A. Cormack
- Department of Radiation Oncology; Brigham and Womens Hospital and Dana-Faber Cancer Institute; Boston MA 02215 USA
- Harvard Medical School; Boston MA 02215 USA
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Guthier CV, Aschenbrenner KP, Müller R, Polster L, Cormack RA, Hesser JW. Real-time inverse high-dose-rate brachytherapy planning with catheter optimization by compressed sensing-inspired optimization strategies. Phys Med Biol 2016; 61:5956-72. [DOI: 10.1088/0031-9155/61/16/5956] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Reynés-Llompart G, Pino F, Modolell I, Gullón C, Pera J, Gutierrez C, Picón C. Impact of prostate catheter displacement in inverse planning–simulated annealing and geometric optimization. Brachytherapy 2016; 15:112-7. [DOI: 10.1016/j.brachy.2015.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 10/14/2015] [Accepted: 10/18/2015] [Indexed: 11/17/2022]
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19
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Borot de Battisti M, Maenhout M, Denis de Senneville B, Hautvast G, Binnekamp D, Lagendijk JJW, van Vulpen M, Moerland MA. An automated optimization tool for high-dose-rate (HDR) prostate brachytherapy with divergent needle pattern. Phys Med Biol 2015; 60:7567-83. [PMID: 26378657 DOI: 10.1088/0031-9155/60/19/7567] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Focal high-dose-rate (HDR) for prostate cancer has gained increasing interest as an alternative to whole gland therapy as it may contribute to the reduction of treatment related toxicity. For focal treatment, optimal needle guidance and placement is warranted. This can be achieved under MR guidance. However, MR-guided needle placement is currently not possible due to space restrictions in the closed MR bore. To overcome this problem, a MR-compatible, single-divergent needle-implant robotic device is under development at the University Medical Centre, Utrecht: placed between the legs of the patient inside the MR bore, this robot will tap the needle in a divergent pattern from a single rotation point into the tissue. This rotation point is just beneath the perineal skin to have access to the focal prostate tumor lesion. Currently, there is no treatment planning system commercially available which allows optimization of the dose distribution with such needle arrangement. The aim of this work is to develop an automatic inverse dose planning optimization tool for focal HDR prostate brachytherapy with needle insertions in a divergent configuration. A complete optimizer workflow is proposed which includes the determination of (1) the position of the center of rotation, (2) the needle angulations and (3) the dwell times. Unlike most currently used optimizers, no prior selection or adjustment of input parameters such as minimum or maximum dose or weight coefficients for treatment region and organs at risk is required. To test this optimizer, a planning study was performed on ten patients (treatment volumes ranged from 8.5 cm(3)to 23.3 cm(3)) by using 2-14 needle insertions. The total computation time of the optimizer workflow was below 20 min and a clinically acceptable plan was reached on average using only four needle insertions.
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Affiliation(s)
- M Borot de Battisti
- Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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Dinkla AM, van der Laarse R, Kaljouw E, Pieters BR, Koedooder K, van Wieringen N, Bel A. A comparison of inverse optimization algorithms for HDR/PDR prostate brachytherapy treatment planning. Brachytherapy 2015; 14:279-88. [DOI: 10.1016/j.brachy.2014.09.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 09/11/2014] [Accepted: 09/11/2014] [Indexed: 10/24/2022]
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Guthier C, Aschenbrenner KP, Buergy D, Ehmann M, Wenz F, Hesser JW. A new optimization method using a compressed sensing inspired solver for real-time LDR-brachytherapy treatment planning. Phys Med Biol 2015; 60:2179-94. [DOI: 10.1088/0031-9155/60/6/2179] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Balvert M, Gorissen BL, den Hertog D, Hoffmann AL. Dwell time modulation restrictions do not necessarily improve treatment plan quality for prostate HDR brachytherapy. Phys Med Biol 2014; 60:537-48. [DOI: 10.1088/0031-9155/60/2/537] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Mazaheri Y, Afaq AA, Jung SI, Goldman DA, Wang L, Aslan H, Zelefsky MJ, Akin O, Hricak H. Volume and landmark analysis: comparison of MRI measurements obtained with an endorectal coil and with a phased-array coil. Clin Radiol 2014; 70:379-86. [PMID: 25554540 DOI: 10.1016/j.crad.2014.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 11/26/2014] [Accepted: 12/03/2014] [Indexed: 11/27/2022]
Abstract
AIM To compare prostate volumes and distances between anatomical landmarks on MRI images obtained with a phased-array coil (PAC) only and with a PAC and an endorectal coil (ERC). MATERIALS AND METHODS Informed consent was waived for this Health Insurance Portability and Accountability Act-compliant study. Fifty-nine men underwent PAC-MRI and ERC-MRI at 1.5 (n = 3) or 3 T (n = 56). On MRI images, two radiologists independently measured prostate volume and distances between the anterior rectal wall (ARW) and symphysis pubis at the level of the verumontanum; ARW and symphysis pubis at the level of the mid-symphysis pubis; and bladder neck and mid-symphysis pubis. Differences between measurements from PAC-MRI and ERC-MRI were assessed with the Wilcoxon RANK SUM test. Inter-reader agreement was assessed using the concordance correlation coefficient (CCC). RESULTS Differences in prostate volume between PAC-MRI and ERC-MRI [median: -0.75 mm(3) (p = 0.10) and median: -0.84 mm(3) (p = 0.06) for readers 1 and 2, respectively] were not significant. For readers 1 and 2, median differences between distances were as follows: -10.20 and -12.75 mm, respectively, ARW to symphysis pubis at the level of the verumontanum; -6.60 and -6.08 mm, respectively, ARW to symphysis pubis at the level of the mid-symphysis pubis; -3 and -3 mm respectively, bladder neck to mid-symphysis pubis. All differences in distance were significant for both readers (p ≤ 0.0005). Distances were larger on PAC-MRI (p ≤ 0.0005). Inter-reader agreement regarding prostate volume was almost perfect on PAC-MRI (CCC: 0.99; 95% CI: 0.98-1.00) and ERC-MRI (CCC: 0.99; 95% CI: 0.99-1.00); inter-reader agreement for distance measurements varied (CCCs: 0.54-0.86). CONCLUSION Measurements of distances between anatomical landmarks differed significantly between ERC-MRI and PAC-MRI, although prostate volume measurements did not.
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Affiliation(s)
- Y Mazaheri
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, USA; Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
| | - A A Afaq
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - S I Jung
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - D A Goldman
- Department of Epidemiology & Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - L Wang
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - H Aslan
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - M J Zelefsky
- Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - O Akin
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - H Hricak
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
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Dinkla AM, van der Laarse R, Koedooder K, Petra Kok H, van Wieringen N, Pieters BR, Bel A. Novel tools for stepping source brachytherapy treatment planning: Enhanced geometrical optimization and interactive inverse planning. Med Phys 2014; 42:348-53. [DOI: 10.1118/1.4904020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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De Boeck L, Beliën J, Egyed W. Dose optimization in high-dose-rate brachytherapy: A literature review of quantitative models from 1990 to 2010. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.orhc.2013.12.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Deufel CL, Furutani KM. Quality assurance for high dose rate brachytherapy treatment planning optimization: using a simple optimization to verify a complex optimization. Phys Med Biol 2014; 59:525-40. [DOI: 10.1088/0031-9155/59/3/525] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Manikandan A, Sarkar B, Rajendran VT, King PR, Sresty NVM, Holla R, Kotur S, Nadendla S. Role of step size and max dwell time in anatomy based inverse optimization for prostate implants. J Med Phys 2013; 38:148-54. [PMID: 24049323 PMCID: PMC3775040 DOI: 10.4103/0971-6203.116380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2013] [Revised: 06/25/2013] [Accepted: 06/26/2013] [Indexed: 11/25/2022] Open
Abstract
In high dose rate (HDR) brachytherapy, the source dwell times and dwell positions are vital parameters in achieving a desirable implant dose distribution. Inverse treatment planning requires an optimal choice of these parameters to achieve the desired target coverage with the lowest achievable dose to the organs at risk (OAR). This study was designed to evaluate the optimum source step size and maximum source dwell time for prostate brachytherapy implants using an Ir-192 source. In total, one hundred inverse treatment plans were generated for the four patients included in this study. Twenty-five treatment plans were created for each patient by varying the step size and maximum source dwell time during anatomy-based, inverse-planned optimization. Other relevant treatment planning parameters were kept constant, including the dose constraints and source dwell positions. Each plan was evaluated for target coverage, urethral and rectal dose sparing, treatment time, relative target dose homogeneity, and nonuniformity ratio. The plans with 0.5 cm step size were seen to have clinically acceptable tumor coverage, minimal normal structure doses, and minimum treatment time as compared with the other step sizes. The target coverage for this step size is 87% of the prescription dose, while the urethral and maximum rectal doses were 107.3 and 68.7%, respectively. No appreciable difference in plan quality was observed with variation in maximum source dwell time. The step size plays a significant role in plan optimization for prostate implants. Our study supports use of a 0.5 cm step size for prostate implants.
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Affiliation(s)
- Arjunan Manikandan
- Department of Radiotherapy, Indo American Cancer Hospital and Research Centre, Hyderabad, Andhra Pradesh, India
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Holm Å, Larsson T, Tedgren ÅC. A linear programming model for optimizing HDR brachytherapy dose distributions with respect to mean dose in the DVH-tail. Med Phys 2013; 40:081705. [DOI: 10.1118/1.4812677] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Gorissen BL, den Hertog D, Hoffmann AL. Mixed integer programming improves comprehensibility and plan quality in inverse optimization of prostate HDR brachytherapy. Phys Med Biol 2013; 58:1041-57. [DOI: 10.1088/0031-9155/58/4/1041] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Holm Å, Larsson T, Carlsson Tedgren Å. Impact of using linear optimization models in dose planning for HDR brachytherapy. Med Phys 2012; 39:1021-8. [DOI: 10.1118/1.3676179] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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D’Amours M, Pouliot J, Dagnault A, Verhaegen F, Beaulieu L. Patient-Specific Monte Carlo-Based Dose-Kernel Approach for Inverse Planning in Afterloading Brachytherapy. Int J Radiat Oncol Biol Phys 2011; 81:1582-9. [DOI: 10.1016/j.ijrobp.2010.09.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 09/03/2010] [Accepted: 09/21/2010] [Indexed: 11/27/2022]
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Siauw T, Cunha A, Atamtürk A, Hsu IC, Pouliot J, Goldberg K. IPIP: A new approach to inverse planning for HDR brachytherapy by directly optimizing dosimetric indices. Med Phys 2011; 38:4045-51. [PMID: 21859003 DOI: 10.1118/1.3598437] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Many planning methods for high dose rate (HDR) brachytherapy require an iterative approach. A set of computational parameters are hypothesized that will give a dose plan that meets dosimetric criteria. A dose plan is computed using these parameters, and if any dosimetric criteria are not met, the process is iterated until a suitable dose plan is found. In this way, the dose distribution is controlled by abstract parameters. The purpose of this study is to develop a new approach for HDR brachytherapy by directly optimizing the dose distribution based on dosimetric criteria. METHODS The authors developed inverse planning by integer program (IPIP), an optimization model for computing HDR brachytherapy dose plans and a fast heuristic for it. They used their heuristic to compute dose plans for 20 anonymized prostate cancer image data sets from patients previously treated at their clinic database. Dosimetry was evaluated and compared to dosimetric criteria. RESULTS Dose plans computed from IPIP satisfied all given dosimetric criteria for the target and healthy tissue after a single iteration. The average target coverage was 95%. The average computation time for IPIP was 30.1 s on an Intel(R) Core 2 Duo CPU 1.67 GHz processor with 3 Gib RAM. CONCLUSIONS IPIP is an HDR brachytherapy planning system that directly incorporates dosimetric criteria. The authors have demonstrated that IPIP has clinically acceptable performance for the prostate cases and dosimetric criteria used in this study, in both dosimetry and runtime. Further study is required to determine if IPIP performs well for a more general group of patients and dosimetric criteria, including other cancer sites such as GYN.
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Affiliation(s)
- Timmy Siauw
- Department of Civil and Environmental Engineering, University of California, Berkeley, 760 Davis Hall, Berkeley, California 94720-1710, USA.
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Murali V, Kurup PGG, Mahadev P, Mahalakshmi S. Dosimetric analysis and comparison of IMRT and HDR brachytherapy in treatment of localized prostate cancer. J Med Phys 2011; 35:113-9. [PMID: 20589121 PMCID: PMC2884303 DOI: 10.4103/0971-6203.62201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Revised: 09/25/2009] [Accepted: 12/30/2009] [Indexed: 11/04/2022] Open
Abstract
Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage.
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Affiliation(s)
- V Murali
- Department of Radiation Oncology, Apollo Speciality Hospital, 320, Anna Salai, Chennai-600 035, India
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Radiobiological evaluation of the influence of dwell time modulation restriction in HIPO optimized HDR prostate brachytherapy implants. J Contemp Brachytherapy 2010; 2:117-128. [PMID: 27853473 PMCID: PMC5104831 DOI: 10.5114/jcb.2010.16923] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 09/01/2010] [Indexed: 12/25/2022] Open
Abstract
Purpose One of the issues that a planner is often facing in HDR brachytherapy is the selective existence of high dose volumes around some few dominating dwell positions. If there is no information available about its necessity (e.g. location of a GTV), then it is reasonable to investigate whether this can be avoided. This effect can be eliminated by limiting the free modulation of the dwell times. HIPO, an inverse treatment plan optimization algorithm, offers this option. In treatment plan optimization there are various methods that try to regularize the variation of dose non-uniformity using purely dosimetric measures. However, although these methods can help in finding a good dose distribution they do not provide any information regarding the expected treatment outcome as described by radiobiology based indices. Material and methods The quality of 12 clinical HDR brachytherapy implants for prostate utilizing HIPO and modulation restriction (MR) has been compared to alternative plans with HIPO and free modulation (without MR). All common dose-volume indices for the prostate and the organs at risk have been considered together with radiobiological measures. The clinical effectiveness of the different dose distributions was investigated by calculating the response probabilities of the tumors and organs-at-risk (OARs) involved in these prostate cancer cases. The radiobiological models used are the Poisson and the relative seriality models. Furthermore, the complication-free tumor control probability, P+ and the biologically effective uniform dose (D¯¯) were used for treatment plan evaluation and comparison. Results Our results demonstrate that HIPO with a modulation restriction value of 0.1-0.2 delivers high quality plans which are practically equivalent to those achieved with free modulation regarding the clinically used dosimetric indices. In the comparison, many of the dosimetric and radiobiological indices showed significantly different results. The modulation restricted clinical plans demonstrated a lower total dwell time by a mean of 1.4% that was proved to be statistically significant (p = 0.002). The HIPO with MR treatment plans produced a higher P+ by 0.5%, which stemmed from a better sparing of the OARs by 1.0%. Conclusions Both the dosimetric and radiobiological comparison shows that the modulation restricted optimization gives on average similar results with the optimization without modulation restriction in the examined clinical cases. Concluding, based on our results, it appears that the applied dwell time regularization technique is expected to introduce a minor improvement in the effectiveness of the optimized HDR dose distributions.
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Ruotsalainen H, Miettinen K, Palmgren JE, Lahtinen T. Interactive multiobjective optimization for anatomy-based three-dimensional HDR brachytherapy. Phys Med Biol 2010; 55:4703-19. [DOI: 10.1088/0031-9155/55/16/006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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