Dosimetric effect of intensity-modulated radiation therapy for postoperative non-small cell lung cancer with and without air cavity in the planning target volume
To evaluate the dosimetric effect of intensity-modulated radiation therapy (IMRT) for postoperative non-small cell lung cancer (NSCLC), with and without the air cavity in the planning target volume (PTV). Two kinds of IMRT plans were made for 21 postoperative NSCLC patients. In Plan-0: PTV included the tracheal air cavity, and in Plan-1: the air cavity was subtracted from the PTV. For PTV, the dosimetric parameters, including Dmean, D98, D95, D2, D0.2, conformity index (CI), and homogeneity index (HI) were evaluated. (Source: Medical Dosimetry)
Source: Medical Dosimetry - September 19, 2021 Category: Radiology Authors: Wutian Gan, Yanhua Duan, Hao Wang, Yan Shao, Hua Chen, Aihui Feng, Hengle Gu, Ying Huang, Yanchen Ying, Xiaolong Fu, Hong Quan, Zhiyong Xu Source Type: research
Assessment of HDR brachytherapy-replicating prostate radiotherapy planning for tomotherapy, cyberknife and VMAT
A dosimetric study was undertaken to assess the ability of Cyberknife (CK), Volumetric Modulated Arc Therapy (VMAT), and TomoTherapy (Tomo) to generate treatment plans that mimic the dosimetry of high dose-rate brachytherapy (HDR BT) for prostate cancer. The project aimed to assess the potential of using stereotactic body radiotherapy (SBRT) for boost treatment of high-risk prostate cancer patients where HDR BT in combination with conformal external beam radiotherapy (EBRT) is the standard of care. (Source: Medical Dosimetry)
Source: Medical Dosimetry - September 19, 2021 Category: Radiology Authors: Romena de Chavez, Garry Grogan, Ben Hug, Kate Howe, Alice Grigg, David Waterhouse, Jonathan Lane, Alan Glyde, Elizabeth Brown, Sean Bydder, David Pryor, Cathy Hargrave, Paul H. Charles, James Hellyer, Martin A. Ebert Source Type: research
Treatment planning comparison between dynamic wave arc and volumetric modulated arc therapies for prostate-cancer treatment
The aim of this study was to compare the quality of dynamic wave arc (DWA) and coplanar volumetric modulated arc therapy (co-VMAT) plans for the treatment of localized prostate cancer. The planning target volume (PTV)-rectum, a section of the PTV comprising the PTV minus that of the rectum, received 78 Gy in 39 fractions as the mean dose to the PTV-rectum. The DWA and co-VMAT plans were generated for each patient using the RayStation treatment planning system for the Vero4DRT system. The PTV-rectum dose (D95%: the percent dose irradiating 95% of the volume), homogeneity index (HI), conformity index (CI), as well as doses t...
Source: Medical Dosimetry - September 16, 2021 Category: Radiology Authors: Hideharu Miura, Minoru Nakao, Yoshiko Doi, Shuichi Ozawa, Masahiko Kenjo, Yasushi Nagata Tags: Clinical Radiation Oncology Contribution Source Type: research
Plan quality and consistency in spine radiosurgery treatment planning: comparison between automatic treatment planning with Elements Spine SRS and manual inverse planning with Varian Eclipse
Spine radiosurgery treatment planning can be a challenging task since a high radiation dose is delivered to target volumes close to the spinal cord, therefore a steep dose gradient is required. Plan quality is greatly influenced by the planner skills, so automatic treatment planning has been proposed to overcome this issue and assure high-quality plans. The Brainlab Elements Spine SRS treatment planning system is specially designed for spine radiosurgery treatments. It is an automatic treatment planning system that works through predefined protocols, with minimal planner interaction required. (Source: Medical Dosimetry)
Source: Medical Dosimetry - September 16, 2021 Category: Radiology Authors: Maria A. Piliero, Francesco Pupillo, Stefano Leva, Margherita Casiraghi, Eleonora Paulicelli, Luca Bellesi, Stefano Presilla Tags: Dosimetry Contribution Source Type: research
Fully automated planning and delivery of hippocampal-sparing whole brain irradiation
The goal of this study is to fully automate the treatment planning and delivery process of hippocampal-sparing whole brain irradiation (HS-WBRT) by combining a RapidPlan (RP) knowledge-based planning model and HyperArc (HA) technology. Additionally, this study compares the dosimetric performance of RapidPlan-HyperArc (RP-HA) treatment plans with RP plans and volumetric modulated arc therapy (VMAT) plans.Ten patients previously treated with HS-WBRT using conventional VMAT were re-planned using RP-HA technique and RP model for HS-WBRT. (Source: Medical Dosimetry)
Source: Medical Dosimetry - September 1, 2021 Category: Radiology Authors: Iris Rusu, John Roeske, Abhishek Solanki, Hyejoo Kang Source Type: research
Analysis of potential time saving in brain arteriovenous malformation stereotactic radiosurgery planning using a new software platform
To evaluate the utility of integrating a 3D vessel tree co-registration software platform into the stereotactic radiosurgery (SRS) workflow and its time saving for brain arteriovenous malformation (bAVM) treatment in adults compared to the conventional stereotactic head frame workflow. Eight consecutive adult bAVM cases were selected and retrospectively reviewed. Total number of angiograms and SRS procedures were 8. The electronic medical records were analyzed by time stamps to determine the length of time for each component of the set-up, transport, and frame removal. (Source: Medical Dosimetry)
Source: Medical Dosimetry - September 1, 2021 Category: Radiology Authors: Guilherme Dabus, Rupesh Kotecha, Italo Linfante, D Jay Wieczorek, Alonso N Gutierrez, John G Candela, Michael W McDermott Source Type: research
Dosimetric comparison of intensity modulated radiotherapy and intensity modulated proton therapy in the treatment of recurrent nasopharyngeal carcinoma
To compare the dosimetric performance of Intensity Modulated Proton Therapy (IMPT) and Intensity Modulated Radiotherapy (IMRT) in terms of target volume coverage and sparing of neurological organs-at-risk (OARs) in salvaging recurrent nasopharyngeal carcinoma (rNPC). The maximum dose to the internal carotid artery (ICA) and nasopharyngeal (NP) mucosa, which are associated with potential carotid blowout and massive epistaxis, were also evaluated. (Source: Medical Dosimetry)
Source: Medical Dosimetry - August 29, 2021 Category: Radiology Authors: Hing Ming Hung, Oliver Cheuk Ming Chan, Chi Hang Mak, Wai Man Hung, Wai Tong Ng, Michael Chi Hang Lee Source Type: research
A Planning Comparison of IMRT vs. Pencil Beam Scanning for Deep Inspiration Breath Hold Lung Cancers
Deep inspiration breath hold (DIBH) has dosimetric advantages for lung cancer patients treated with external beam therapy, but is difficult for many patients to perform. Proton therapy permits sparing of the downstream organs at risk (OAR). We compared conventionally fractionated proton (p) and photon(x) plans on both free breathing (FB) and DIBH planning CTs to determine the effect of DIBH with proton therapy. We evaluated 24 plans from 6 lung cancer patients treated with photon DIBH on a prospective protocol. (Source: Medical Dosimetry)
Source: Medical Dosimetry - August 20, 2021 Category: Radiology Authors: Dennis Mah, Ellen Yorke, Entela Zemanaj, Zhiqiang Han, Haoyang Liu, Jobin George, Jason Lambiase, Christian Czmielewski, D. Michael Lovelock, Andreas Rimner, Annemarie F. Shepherd Source Type: research
Double-vertebral segment SBRT via novel ring-mounted Halcyon Linac: Plan quality, delivery efficiency and accuracy
To evaluate the plan quality, treatment delivery efficiency, and accuracy of single-isocenter/multi-target (SIMT) volumetric modulated arc therapy (VMAT) of double-vertebral segments stereotactic body radiation therapy (SBRT) on Halcyon ring delivery system (RDS). In-house multi-target end-to-end phantom testing and independent dose verification using the MD Anderson's single-isocenter/multi-target (lung/spine targets) thorax phantom were completed. Six previously treated patients with 2-vertebral segments on thoracic and/or lumber spine were replanned on Halcyon RDS with 6MV-FFF beam using a single-isocenter placed betwee...
Source: Medical Dosimetry - August 16, 2021 Category: Radiology Authors: Damodar Pokhrel, Joseph Stephen, Aaron Webster, Mark E. Bernard Source Type: research
Auto-delineation framework for the focal liver reaction observed in post Stereotactic Body Radiation Therapy (SBRT) Primovist MRI scans
Development of a novel auto-delineation methodology for observed hypointensity from focal liver reaction in hepatobiliary-specific contrast (Primovist) enhanced MRI acquired post Stereotactic Body Radiation Therapy (SBRT). Additionally, the methodology for the quantification of the threshold dose associated with the observed focal liver reaction was also established. An auto-delineation algorithm was created based on the correlation between intensity and radiation dose information. The error associated with the auto-delineation was quantified using virtual FLRs, as well as clinical patient scans. (Source: Medical Dosimetry)
Source: Medical Dosimetry - August 8, 2021 Category: Radiology Authors: Svetlana Kuznetsova, Petra Grendarova, Rishi Sinha, Nicolas Ploquin, Kundan Thind Source Type: research
Selection of brachytherapy applicators based on tumor size and shape for cervical cancer: simulation analysis of pear-shaped isodose dimensions
The purpose of study is to measure Point A pear-shaped isodose dimensions of the conventional intracavitary brachytherapy with various sizes of colpostats and analyze which size of tumor is the optimal for 3-D interstitial brachytherapy. CT simulation was performed with Fletcher type applicator using various sizes of colpostats (2.0, 2.5, and 3.0 cm diameter). The Manchester standard loading (dwell time) system was used to generate pear-shaped isodose envelopes with high-dose rate iridium-192 according to the colpostat sizes. (Source: Medical Dosimetry)
Source: Medical Dosimetry - August 2, 2021 Category: Radiology Authors: Robert Y. Kim, Samuel R. Marcrom, Sui Shen Source Type: research
Pituitary adenoma treatment plan quality comparison between linear accelerator volumetric modulated arc therapy and Leksell Gamma Knife ® radiosurgery
The aim of this study was to compare radiosurgical treatment plan quality of a linear accelerator with Leksell Gamma Knife (LGK) for pituitary adenoma irradiation. Thirty pituitary adenoma patients were evaluated in this study. Treatment plans were prepared on LGK and stereotactic linear accelerator Varian TrueBeam STx. Volumetric Modulated Arc Therapy (VMAT) plans (21 plans with 2 coplanar arcs and 9 plans with 4 non-coplanar arcs) were calculated for linear accelerator. All the plans were evaluated in terms of conformity, selectivity, gradient index and organ at risk (OAR) sparing. (Source: Medical Dosimetry)
Source: Medical Dosimetry - July 23, 2021 Category: Radiology Authors: T. Veselsky, T. Syruckova, A. Kindlova, P. Osmancikova Source Type: research
Magnetic resonance image-guided hypofractionated ablative radiation therapy for extrahepatic cholangiocarcinoma: Plan adaptation in changing anatomy
Extrahepatic cholangiocarcinoma is an aggressive malignancy of biliary duct epithelium which typically has a poor prognosis. Although surgical resection improves overall survival, many patients are deemed medically inoperable or have unresectable tumors. Herein, we report a case of an 84-year-old Caucasian male who was diagnosed with medically inoperable extrahepatic cholangiocarcinoma. Magnetic resonance image-guided hypofractionated ablative radiotherapy was administered which has the advantages of superior soft tissue resolution, better visualization of the target and organ at risk, daily online adaptive planning and co...
Source: Medical Dosimetry - July 7, 2021 Category: Radiology Authors: Sebnem Egriboyun, Gamze Ugurluer, Gorkem Gungor, Teuta Zoto Mustafayev, Bahattin Cicek, Gokhan Demir, Banu Atalar, Enis Ozyar Source Type: research
The effect of measurement geometry on patient specific QA pass/fail rates for stereotactic body radiation therapy (SBRT) Plans
Patient quality assurance (QA) is a required part of the treatment care path, and plan failure can lead to increased personnel hours or delay of treatment. The recommendation by the American Association of Physicists in Medicine is that gamma analysis be used to evaluate measured volumetric modulated arc therapy plans. Vendors have developed many different measurement geometries for patient QA devices which could yield varying pass rates when used with the recommended tolerances, normalization, and criterion. (Source: Medical Dosimetry)
Source: Medical Dosimetry - June 24, 2021 Category: Radiology Authors: Courtney S Hadsell, Nishele. Lenards, Ashley. Hunzeker, Michael J. Tallhamer, Michael J. Hadsell Source Type: research
Prostate radiotherapy in the setting of bilateral hip prostheses: All commonly used photon-based radiation approaches are feasible
The prevalence of hip prostheses is increasing. Prostate radiation delivery in the setting of hip prostheses is complicated by both imaging artifacts that interfere with volume delineation and dosimetric effects that must be addressed in the planning process. We hypothesized that with specialized planning, any photon-based definitive prostate radiotherapy approach may be utilized in patients with bilateral hip prostheses. Imaging data from sequential patients with prostate cancer and bilateral hip prostheses treated definitively with radiation were retrospectively reviewed. (Source: Medical Dosimetry)
Source: Medical Dosimetry - June 24, 2021 Category: Radiology Authors: Matthew M. Cousins, Eric Short, Paul Heckman, Vrinda Narayana, Alex K. Bryant, Patrick Hurley, Jason Hearn, Patrick W. McLaughlin Source Type: research
