Category Ranking
98%
Total Visits
921
Avg Visit Duration
2 minutes
Citations
20
Article Abstract
Background: This work aimed to determine the optimum VOLO Ultra algorithm parameters for tomotherapy treatments.
Methods: 1056 treatment plans were generated with VOLO Ultra for 36 patients and six anatomical locations. The impact of varying four parameters was studied: the accelerated treatment (AT), leaf open/close time (LOT) cutoff, normal tissue objective (NTO) weight, and number of iterations. The beam-on time and dosimetric metrics were quantified for the target volumes and organs at risk (OARs). Delivery quality assurance measurements were obtained for 36 plans to assess the delivery accuracy.
Results: The mean beam-on time for the helical tomotherapy and TomoDirect (TD) plans decreased by 26.6 ± 2.8% and 17.4 ± 4.3%, respectively, when the accelerated treatment parameter was increased from 0 to 10, at the expense of the planning target volume (PTV) coverage (2% lower D) and OAR dose (up to 15% increase). For TD plans, it seems preferable to systematically use an AT value of 10. Increasing the number of iterations beyond six seems unnecessary. In this study, an NTO weight of approximately 10 appears to be ideal and eliminates the need to use rings in the treatment plan. Finally, no correlation was found between the leaf open/close time cutoff and the delivery accuracy, while a leaf open/close cutoff of 60 ms seemed to degrade dosimetry quality.
Conclusion: Optimal values for the AT, LOT cutoff, NTO weight, and number of optimization rounds were identified and should help improve the management of patients whose tomotherapy treatments are planned with VOLO Ultra.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11119142 | PMC |
| http://dx.doi.org/10.3390/cancers16101883 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Dosimetric accuracy of low dose rate volumetric modulated arc therapy delivery in an Elekta Versa HD linear accelerator for pulsed low dose rate treatment of recurrent high-grade glioma using Monaco planning system: Low dose rate VMAT-based PLDR in Elekta Linac.
J Appl Clin Med Phys
September 2025
Department of Physics, School of Advanced Sciences, Vellore Institute of Technology, Vellore, Tamilnadu, India.
Background And Purpose: Reducing the dose rate enhances efficacy in radiation therapy by allowing increased repair of sub-lethal damage. Pulsed low-dose radiation therapy (PLDR) is an innovative approach that is safe and effective for the reirradiation of recurrent gliomas and radioresistant tumors. In this study, the accuracy of the low dose rate volumetric modulated arc therapy (VMAT) delivery is tested in an Elekta Versa HD linear accelerator (linac) for delivering PLDR.
View Article and Find Full Text PDFDevelopment and demonstration of end-to-end testing for intra-fraction motion-managed workflows.
Med Phys
September 2025
Department of Radiotherapy, University Medical Center Utrecht, Utrecht, the Netherlands.
Background: Intra-fraction motion management techniques, including beam gating and intra-fraction drift correction (IDC), have recently been introduced on the Unity MR-linac (Elekta AB, Stockholm, Sweden) to mitigate the dosimetric impact of motion during treatment. However, residual motion (e.g.
View Article and Find Full Text PDFOptimizing lung SBRT delivery: A hybrid approach combining dynamic conformal arc (DCA) and volumetric modulated arc therapy (VMAT) techniques.
J Appl Clin Med Phys
September 2025
Department of Radiation Oncology, Henry Ford Health System, Detroit, Michigan, USA.
Purpose: This study introduces and evaluates a hybrid dynamic conformal arc-volumetric modulated arc therapy (hDCA-VMAT) technique for lung stereotactic body radiotherapy (SBRT). The goal is to combine the planning efficiency of VMAT with the delivery robustness of dynamic conformal arc (DCA) techniques, particularly for low-density lung targets where motion and dose calculation uncertainties pose challenges.
Methods: Twenty-four previously treated lung SBRT cases were retrospectively replanned using hDCA-VMAT, conventional VMAT, and aperture controlled VMAT (VMAT_AC).
Impact of dynamic jaw width adjustment in tomotherapy on hippocampus sparing and treatment efficiency in whole-brain radiotherapy.
Radiol Phys Technol
August 2025
Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Center, New Delhi, India.
The aim of this study is to evaluate the impact of dynamic jaw width adjustment in tomotherapy on hippocampal sparing, target dose conformity, and treatment efficiency in hippocampal-avoidance whole-brain radiotherapy (HA-WBRT), in accordance with RTOG 0933 guidelines. A retrospective study of 60 patients treated with HA-WBRT was conducted. CT-MRI fusion facilitated accurate hippocampal delineation.
View Article and Find Full Text PDFTime-resolved biological effective dose distributions in stereotactic radiosurgery for vestibular schwannomas: a comparative analysis between two dedicated stereotactic radiosurgery systems.
Phys Med Biol
August 2025
Medical School, National and Kapodistrian University of Athens, Mikras Asias 75, Goudi, Athens, 11527, GREECE.
Stereotactic radiosurgery (SRS) delivered using a step-and-shoot approach, using either isocentric or non-isocentric radiation beams, typically results in distinct treatment delivery patterns across different SRS systems, reflected in treatment time. In this study, we performed a comparative analysis of dosimetric and radiobiological properties of the CyberKnife(CK) and the Gamma Knife(GK) systems in the management of vestibular schwannomas (VS). Approach: The treatment plan and delivery data of 21 patients underwent GK SRS for VS tumors were retrospectively evaluated and compared to corresponding treatment plan calculations performed for the CK.
View Article and Find Full Text PDF