scholarly journals Verification of calculations carried out with the Eclipse treatment planning system

2018 ◽  
Vol 24 (3) ◽  
pp. 109-114
Author(s):  
Habib Ahmad ◽  
Misbah Ahmad ◽  
Shahid Ali ◽  
M. Rauf Khattak ◽  
Wajeeha Shaheen ◽  
...  
Keyword(s):  
Treatment Planning ◽  
Target Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Photon Beams ◽  
Maximum Minimum

Abstract The goal of radiotherapy is to deliver prescribed dose to the target volume and simultaneously minimize the dose to the healthy organs. The purpose of this work was to verify the accuracy of calculations carried out with a treatment planning system (TPS). Measurements carried out with thermoluminescence detectors (TLDs) were compared with doses calculated with TPS. Doses were measured and calculated both in the open beam’s region and under individual blocks. Measurements were performed in the Randophantom. The work was carried out for photon beams generated in the Varian CLINAC 2100C accelerator. The maximum / minimum percentage differences between measured and calculated doses were 4.9/0.6%, 2.6/0%, and 3.5%/0.5% in open, shielded and partially shielded points, respectively. Differences between the measured and calculated doses were within acceptable limits.

scholarly journals Modeling Elekta VersaHD using the Varian Eclipse treatment planning system for photon beams: A single‐institution experience

2019 ◽  
Vol 20 (10) ◽  
pp. 33-42
Author(s):  
You Zhang ◽  
Anh H. Le ◽  
Zhen Tian ◽  
Zohaib Iqbal ◽  
Tsuicheng Chiu ◽  
...  
Keyword(s):  
Treatment Planning ◽  
Planning System ◽  
Treatment Planning System ◽  
Photon Beams ◽  
Single Institution

Utilising virtual bolus in superficial planning target volume dose optimisation (TomoTherapy): a phantom study

2019 ◽  
Vol 19 (1) ◽  
pp. 65-70
Author(s):  
Gim Chee Ooi ◽  
Iskandar Shahrim Bin Mustafa
Keyword(s):  
Treatment Planning ◽  
Planning Target Volume ◽  
Treatment Plan ◽  
Target Volume ◽  
The Body ◽  
Phantom Study ◽  
Planning System ◽  
Treatment Planning System ◽  
Dose Volume Histograms ◽  
Photon Fluence

AbstractAim:This is a phantom study to evaluate the dosimetry effects of using virtual bolus (VB) in TomoTherapy Treatment Planning System (TPS) optimisation for superficial planning target volume (PTV) that extends to the body surface. Without VB, the inverse-planning TPS will continuously boost the photon fluence at the surface of the superficial PTV due to lack of build-up region. VB is used during TPS optimisation only and will not be present in actual treatment delivery.Materials and methods:In this study, a dummy planning target was contoured on a cylindrical phantom which extends to the phantom surface, and VB of various combinations of thickness and density was used in treatment planning optimisation with TomoTherapy TPS. The plans were then delivered with the treatment modality TomoTherapy. Radiochromic films (Gafchromic EBT3) were calibrated and used for dose profiles measurements. TomoTherapy Planned-Adaptive software was used to analyse the delivered Dose-Volume Histograms (DVHs).Results:The use of 2 mm VB was not providing adequate build-up area and was unable to reduce the hot spots during treatment planning and actual delivery. The use of 4 mm VB was able to negate the photon fluence boosting effect by the TPS, and the actual delivery showed relatively small deviations from the treatment plan. The use of 6 mm VB caused significant dose overestimation by the TPS in the superficial regions resulting in insufficient dose coverage delivered.Findings:VB with the combination of 4 mm thickness and 1·0 g/cc density provides the most robust solution for the TomoTherapy TPS optimisation of superficial PTV.

FDG-PET/CT imaging for staging and definition of tumor volumes in radiation treatment planning in non-small cell lung cancer

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 7574-7574 ◽  
Author(s):  
Y. Xu ◽  
S. Ma ◽  
D. Yu ◽  
J. Wang ◽  
L. Zhang ◽  
...  
Keyword(s):  
Treatment Planning ◽  
Fdg Pet ◽  
Radiation Treatment ◽  
Target Volume ◽  
Ct Images ◽  
Planning System ◽  
Treatment Planning System ◽  
Volume Delineation ◽  
Pet Ct ◽  
Fdg Pet Ct

7574 Background: 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) /computed tomography (CT) has a potential improvement for staging and radiation treatment (RT) planning of various tumor sites. But from a clinical standpoint, the open questions are essentially the following: to what extent does PET/CT change the target volume? Can PET/CT reduce inter-observer variability in target volume delineation? We analyzed the use of FDG-PET/ CT images for staging and evaluated the impact of FDG- PET/CT on the radiotherapy volume delineation compared with CT in patients with non-small cell lung cancer (NSCLC) candidates for radiotherapy. Intraobserver variation in delineating tumor volumes was also observed. Methods: Twenty-three patients with stage I-III NSCLC were enrolled in this pilot study and were treated with fractionated RT based therapy with or without chemotherapy. FDG-PET/CT scans were acquired within 2 weeks prior to RT. PET and CT data sets were sent to the treatment planning system Pinnacle through compact disc. The CT and PET images were subsequently fused by means of a dedicated radiation treatment planning system. Gross Tumor Volume (GTV) was contoured by four radiation oncologists respectively on CT (CT-GTV) and PET/CT images (PET/CT-GTV). The resulting volumes were analyzed and compared. Results: For the first phase, two radiation oncologists outlined together the contours achieving a final consensus. Based on PET/CT, changes in TNM categories occurred in 8/23 cases (35%). Radiation targeting with fused FDG-PET and CT images resulted in alterations in radiation therapy planning in 12/20 patients (60%) by comparison with CT targeting. The most prominent changes in GTV have been observed in cases with atelectasis. For the second phase was four intraobserver variation in delineating tumor volumes. The mean ratio of largest to smallest CT-based GTV was 2.31 (range 1.01–5.96). The addition of the PET data reduced the mean ratio to 1.46 (range 1.12–2.27). Conclusions: PET/CT fusion images could have a potential impact on both tumor staging and treatment planning. Implementing matched PET/CT reduced observer variation in delineating tumor volumes significantly with respect to CT only. [Table: see text]

scholarly journals Analyzing the Treatment Delivery Accuracy of the uRT Treatment Planning System and uRT-Linac 506C by Use of AAPM TG 119 Test Cases

2021 ◽  
Author(s):  
DaZhen Jiang ◽  
Dajiang Wang ◽  
Jiuling Shen ◽  
Jun Zhang ◽  
Cheng Chen ◽  
...  
Keyword(s):  
Treatment Planning ◽  
Photon Beam ◽  
Planning System ◽  
Treatment Planning System ◽  
Maximum Deviation ◽  
High Dose ◽  
Photon Beams ◽  
Position Accuracy ◽  
Collapsed Cone ◽  
Beam Mode

Abstract ObjectiveThe objective of this study was to investigate accuracy of the United Imaging Healthcare's uRT treatment planning system (uRT-TPS), by creating AAPM TG 119 test plans with respectively IMRT and VMAT techniques by homogeneous and heterogeneous phantom. Materials and MethodsThe plans were delivered to the homogeneous and heterogeneous phantom using the United Imaging Healthcare's uRT-Linac 506C. The overall dose calculation accuracy by uRT-TPS with Collapsed Cone Convolution (CC) and Monte Carlo (MC) algorithm was measured and analyzed by creating IMRT and VMAT plans for the 5 test geometries specified in TG 119, by using two kinds of beams FF photon beam and FFF photon beam. The point doses were measured with a Farmer type ion chamber and the fluences were measured with films respectively. Results The result of position accuracy was shown that the worst position accuracy is 0.36 mm and the repeated positioning accuracy of MLC field location was less than 0.25mm. The symmetry deviation of MLC was less than 0.08mm. In this study, the CLs of sMLC, dMLC and VMAT plans with FF photon beams were 2.74%, 2.12%, and 1.36% respectively. As for FFF photon beams, they were 3.76%, 2.14% and 2.90% respectively, whereas the counterpart CL specified in TG119 were 4.5% for the high dose regions and 4.7% for OAR regions. The CLs of Gamma Passing rates for sMLC, dMLC and VMAT plans were 4.59%, 5.35% and 2.15% for FF beam mode, and were 1.82%, 6.12% and 4.82% for FFF beam mode. For the heterogeneous phantom, the maximum deviation is 2.35% for CC and 2.63% for MC algorithm respectively.Conclusion Based on this analysis which were performed in accordance with the TG 119 recommendations, it is evident that the URT treatment planning system and URT-Linac 506C have commissioned IMRT and VMAT techniques with adequate accuracy. and all uRT_TPS treatment plans were recognized as clinically acceptable.

scholarly journals Initial Validation of Proton Dose Calculations on SPR Images from DECT in Treatment Planning System

2020 ◽  
Vol 7 (2) ◽  
pp. 51-61
Author(s):  
Sina Mossahebi ◽  
Pouya Sabouri ◽  
Haijian Chen ◽  
Michelle Mundis ◽  
Matthew O'Neil ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Treatment Planning ◽  
Effective Atomic Number ◽  
Dose Calculation ◽  
Target Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Relative Electron ◽  
Treatment Plans ◽  
Proton Dose

Abstract Purpose To investigate and quantify the potential benefits associated with the use of stopping-power-ratio (SPR) images created from dual-energy computed tomography (DECT) images for proton dose calculation in a clinical proton treatment planning system (TPS). Materials and Methods The DECT and single-energy computed tomography (SECT) scans obtained for 26 plastic tissue surrogate plugs were placed individually in a tissue-equivalent plastic phantom. Relative-electron density (ρe) and effective atomic number (Zeff) images were reconstructed from the DECT scans and used to create an SPR image set for each plug. Next, the SPR for each plug was measured in a clinical proton beam for comparison of the calculated values in the SPR images. The SPR images and SECTs were then imported into a clinical TPS, and treatment plans were developed consisting of a single field delivering a 10 × 10 × 10-cm3 spread-out Bragg peak to a clinical target volume that contained the plugs. To verify the accuracy of the TPS dose calculated from the SPR images and SECTs, treatment plans were delivered to the phantom containing each plug, and comparisons of point-dose measurements and 2-dimensional γ-analysis were performed. Results For all 26 plugs considered in this study, SPR values for each plug from the SPR images were within 2% agreement with measurements. Additionally, treatment plans developed with the SPR images agreed with the measured point dose to within 2%, whereas a 3% agreement was observed for SECT-based plans. γ-Index pass rates were > 90% for all SECT plans and > 97% for all SPR image–based plans. Conclusion Treatment plans created in a TPS with SPR images obtained from DECT scans are accurate to within guidelines set for validation of clinical treatment plans at our center. The calculated doses from the SPR image–based treatment plans showed better agreement to measured doses than identical plans created with standard SECT scans.

scholarly journals Treatment planning for proton therapy: what is needed in the next 10 years?

2020 ◽  
Vol 93 (1107) ◽  
pp. 20190304 ◽  
Author(s):  
Hakan Nystrom ◽  
Maria Fuglsang Jensen ◽  
Petra Witt Nystrom
Keyword(s):  
Treatment Planning ◽  
Proton Therapy ◽  
Computational Thinking ◽  
Dose Calculation ◽  
Target Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Biological Efficiency ◽  
Dose Calculation Algorithms ◽  
Computerized Treatment

Treatment planning is the process where the prescription of the radiation oncologist is translated into a deliverable treatment. With the complexity of contemporary radiotherapy, treatment planning cannot be performed without a computerized treatment planning system. Proton therapy (PT) enables highly conformal treatment plans with a minimum of dose to tissues outside the target volume, but to obtain the most optimal plan for the treatment, there are a multitude of parameters that need to be addressed. In this review areas of ongoing improvements and research in the field of PT treatment planning are identified and discussed. The main focus is on issues of immediate clinical and practical relevance to the PT community highlighting the needs for the near future but also in a longer perspective. We anticipate that the manual tasks performed by treatment planners in the future will involve a high degree of computational thinking, as many issues can be solved much better by e.g. scripting. More accurate and faster dose calculation algorithms are needed, automation for contouring and planning is required and practical tools to handle the variable biological efficiency in PT is urgently demanded just to mention a few of the expected improvements over the coming 10 years.

scholarly journals A data-driven method to predict achievability of clinical objectives in IMRT

2021 ◽  
Author(s):  
Vaitheeswaran Ranganathan
Keyword(s):  
Head And Neck ◽  
Treatment Planning ◽  
Region Of Interest ◽  
Target Volume ◽  
Data Driven ◽  
Planning System ◽  
Treatment Planning System ◽  
Geometric Complexity ◽  
Imrt Planning ◽  
Novel Method

Abstract When specifying a clinical objective for a target volume and normal organs/tissues in IMRT planning, the user may not be sure if the defined clinical objective could be achieved by the optimizer. To this end, we propose a novel method to predict the achievability of clinical objectives upfront before invoking the optimization. A new metric called “Geometric Complexity (GC)” is used to estimate the achievability of clinical objectives. Essentially GC is the measure of the number of “unmodulated” beamlets or rays that intersect the Region-of-interest (ROI) and the target volume. We first compute the geometric complexity ratio (GCratio) between the GC of a ROI in a reference plan and the GC of the same ROI in a given plan. The GCratio of a ROI indicates the relative geometric complexity of the ROI as compared to the same ROI in the reference plan. Hence GCratio can be used to predict if a defined clinical objective associated with the ROI can be met by the optimizer for a given case. We have evaluated the proposed method on six Head and Neck cases using Pinnacle3 (version 9.10.0) Treatment Planning System (TPS). Out of total of 42 clinical objectives from six cases accounted in the study, 37 were in agreement with the prediction, which implies an agreement of about 88% between predicted and obtained results. The results indicate the feasibility of using the proposed method in head and neck cases for predicting the achievability of clinical objectives.

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