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Quality assurance for image-guided radiation therapy utilizing CT-based technologies: A report of the AAPM TG-179

Jean-Pierre Bissonnette, Peter A. Balter, Lei Dong, Katja M. Langen, D. Michael Lovelock, Moyed Miften, Douglas J. Moseley, Jean Pouliot, Jan-Jakob Sonke, Sua Yoo
2012 Medical Physics (Lancaster)  
Purpose: Commercial CT-based image-guided radiotherapy (IGRT) systems allow widespread management of geometric variations in patient setup and internal organ motion.  ...  Conclusion: A program for quality control of CT-based image-guidance systems has been produced, with focus on geometry, image quality, image dose, system operation, and safety.  ...  brain and lung cancers.  ... 
doi:10.1118/1.3690466 pmid:22482616 fatcat:pg55536advbpna6yupsak4veyq

Proton dose calculation on scatter-corrected CBCT image: Feasibility study for adaptive proton therapy

Yang-Kyun Park, Gregory C. Sharp, Justin Phillips, Brian A. Winey
2015 Medical Physics (Lancaster)  
Soft tissue ROI-based HU shifting was used to improve HU accuracy of the uncorrected CBCT images and CBCT us , while no HU change was applied to the CBCT ap .  ...  The CBCT ap was further evaluated in more realistic scenarios such as rectal filling and weight loss to assess the effect of mismatched prior information on the corrected images.  ...  plans were simulated on the CT and CBCT images of the phantoms as follows: (1) a single posterior-oblique field for a brain target with a diameter of 30 mm in the head phantom; (2) two fields (right and  ... 
doi:10.1118/1.4923179 pmid:26233175 pmcid:PMC4517932 fatcat:q5w4umvsjbbbrnnv6a6mlgbf7y

Six degrees of freedom CBCT-based positioning for intracranial targets treated with frameless stereotactic radiosurgery

Anees Dhabaan, Eduard Schreibmann, Arsalan Siddiqi, Eric Elder, Tim Fox, Tomi Ogunleye, Natia Esiashvili, Walter Curran, Ian Crocker, Hui-Kuo Shu
2012 Journal of Applied Clinical Medical Physics  
Mean error in the shifts predicted by the system were less than 0.5 mm in any translational direction and less than 0.3° in any rotation, as assessed by a confirmation CBCT scan.  ...  Here, we present a positioning approach for frameless radiosurgery based on in-room volumetric imaging coupled with an advanced six-degrees-of-freedom (6 DOF) image registration technique which avoids  ...  The alignment accuracy of frame-based radiosurgery of 0.3 mm to 1.5 mm is reported by several studies.  ... 
doi:10.1120/jacmp.v13i6.3916 pmid:23149782 pmcid:PMC5718543 fatcat:qh5sfsajjzfzlisfbcdepz772u

187: Determining Optimal Volumetric Image Guidance Strategies for Breast Boost Radiation Therapy

Winnie Li, Susanne Lofgren, Grace Lee, Paul Kwan, Robert Dinniwell, Douglas Moseley
2016 Radiotherapy and Oncology  
The mean displacements of lens and optic nerve insertion were 0.1 mm and 0.0 mm -confirming that there was no systemic shift from planning to treatment.  ...  The median 3D displacements (absolute value) of lens and nerve insertion were 0.8 and 0.7 mm (SD 0.5 and 0.6 mm). Ninety-eight percent of 3D displacements were below 2 mm (maximum 2.4 mm).  ...  A retrospective investigation was completed to compare the traditional whole brain osseous-based field placement technique to a volumetric based technique with respect to clinical target volume (CTV) coverage  ... 
doi:10.1016/s0167-8140(16)33586-1 fatcat:dm6uve2hsjhd3dlyoepxjci3dq

Quantifying the setup uncertainty of a stereotactic murine micro-image guided radiation therapy system

Matthew C Walb, Brett L Carlson, Jann N Sarkaria, Erik J Tryggestad
2019 British Journal of Radiology  
CBCT shifts were calculated to quantify the accuracy of setup based on couch coordinates alone. For intramouse reproducibility, C57BL/6 mice (N=4) were imaged daily for 7 days.  ...  Each mouse was imaged via cone-beam CT (CBCT). A virtual isocenter target was placed in the brain, the stage shifted to that target, and the couch positions recorded.  ...  All research procedures were performed with the approval of the Institutional Animal Care and Use Committee at Mayo Clinic. funDinG This work was funded by the Mayo SPORE in Brain Cancer CA108961 and Mayo  ... 
doi:10.1259/bjr.20180487 pmid:30299986 pmcid:PMC6541190 fatcat:fywqwpa4hzeqnfivgvn7xawg44

The implementation of MOSAIQ-based image-guided radiation therapy image matching within radiation therapy education

Crispen Chamunyonga, Peta Rutledge, Peter J Caldwell, Julie Burbery
2020 Journal of Medical Radiation Sciences  
The hands-on exposure to case-based planar and volumetric kilovoltage (kV) image matching has resulted in improved teaching and better preparation of students for clinical IGRT encounters.  ...  However, there is limited literature on the acquisition and assessment of IGRT image-matching competencies in undergraduate educational environments.  ...  Conflicts of Interest The authors declare no conflict of interest. IGRT Image matching competency MOSAIQ tutorials VERT tutorials  ... 
doi:10.1002/jmrs.434 pmid:32979303 fatcat:dj7hdehxefactijoxcio2rtq4u

Accuracy in automatic image registration between MV cone beam computed tomography and planning kV computed tomography in image guided radiotherapy

Nithya Kanakavelu, E. James Jebaseelan Samuel
2016 Reports of Practical Oncology & Radiotherapy  
Cone beam computed tomography (CBCT) Image guided radiotherapy (IGRT) a b s t r a c t Aim: To verify the accuracy of automatic image registration (IR) between the planning kilo voltage computed tomography  ...  The IR accuracy was also evaluated on patient images on different anatomical sites such as brain, head & neck, thorax and pelvis.  ...  These sections are used to assess the MV CBCT image quality and geometric accuracy.  ... 
doi:10.1016/j.rpor.2016.07.001 pmid:27489520 pmcid:PMC4961788 fatcat:pawzaxuqpvcu3axaemk4nbv5j4

Intra-fractional patient motion when using the Qfix Encompass immobilization system during HyperArc treatment of patients with brain metastases

Riho Komiyama, Shingo Ohira, Hikari Ueda, Naoyuki Kanayama, Akira Masaoka, Masaru Isono, Yoshihiro Ueda, Masayoshi Miyazaki, Teruki Teshima
2021 Journal of Applied Clinical Medical Physics  
Finally, the correlation between the treatment time and the IM of the 3D vector was assessed.  ...  For the axes of rotation, the r-values were 0.012 and 0.206 for SRS and SRT, respectively. Encompass provided patient immobilization with adequate accuracy during HA treatment.  ...  Finally, CBCT images were acquired after the treatment (post-CBCT) to assess the IM.  ... 
doi:10.1002/acm2.13143 pmid:33656261 fatcat:widfbtjo7zg6he2d5zrr6irism

Is ExacTrac x-ray system an alternative to CBCT for positioning patients with head and neck cancers?

Stefania Clemente, Costanza Chiumento, Alba Fiorentino, Vittorio Simeon, Mariella Cozzolino, Caterina Oliviero, Giorgia Califano, Rocchina Caivano, Vincenzo Fusco
2013 Medical Physics (Lancaster)  
The observed differences in shift vectors between the two protocols showed that CBCT tends to weight more C2 and C6 at the expense of the mandible, while ET tends to average more differences among the  ...  Methods: Local setup accuracy was analyzed for 12 patients undergoing intensity-modulated radiation therapy (IMRT).  ...  Is Exactrac X-Ray System an Alternative to CBCT for Positioning Patients Head and Neck Cancers?  ... 
doi:10.1118/1.4824056 pmid:24320433 fatcat:i4f4u6mljneafb756ucfnfaggi

Dosimetric impact of placement errors in optically stimulated luminescent in vivo dosimetry in radiotherapy

Mahin Tariq, Cindy Gomez, Adam C. Riegel
2019 Physics and Imaging in Radiation Oncology  
The analysis consisted of three parts: first, quantification of placement error in a clinical sample of 128 patients yielding 293 cone-beam CT (CBCT) with visible OSLDs registered to the treatment plan  ...  In the second analysis, placement error and measured-to-planned dose agreement yielded no correlation (R2 = 0.02) for a subsample of 77 CBCTs of 55 head-and-neck patients.  ...  Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper  ... 
doi:10.1016/j.phro.2019.08.004 pmid:33458280 pmcid:PMC7807655 fatcat:gkleuxkvxjdxpfsof4i25dvi7m

Clinical commissioning and use of the Novalis Tx linear accelerator for SRS and SBRT

Jinkoo Kim, Ning Wen, Jian-Yue Jin, Nicole Walls, Sangroh Kim, Haisen Li, Lei Ren, Yimei Huang, Anthony Doemer, Kathleen Faber, Tina Kunkel, Ahssan Balawi (+11 others)
2012 Journal of Applied Clinical Medical Physics  
with the image guidance and MLC requirements to treat a wide variety of sites -in particular for highly accurate delivery of SRS and SBRT-based treatments.  ...  Unshielded stereotactic field diode (SFD) overestimated dose by ~ 2% for large field sizes. Ion chambers with active diameters of 6 mm suffered from significant volume averaging.  ...  (73) compared the qualities of two volumetric CBCT imaging systems, as well as the organ doses. Lee et al. (74) assessed the image quality of the ETX system.  ... 
doi:10.1120/jacmp.v13i3.3729 pmid:22584170 pmcid:PMC5716565 fatcat:kxyon66llzfftirhctqdlb24yy

Evaluating organ delineation, dose calculation and daily localization in an open-MRI simulation workflow for prostate cancer patients

Anthony Doemer, Indrin J Chetty, Carri Glide-Hurst, Teamour Nurushev, David Hearshen, Milan Pantelic, Melanie Traughber, Joshua Kim, Kenneth Levin, Mohamed A Elshaikh, Eleanor Walker, Benjamin Movsas
2015 Radiation Oncology  
Planning margins based on MRI/CBCT shifts were computed using the van Herk formalism. Results: Significant organ contour differences were noted between MRI and CT.  ...  This study describes initial testing and evaluation of a vertical-field open Magnetic Resonance Imaging (MRI) scanner for the purpose of simulation in radiation therapy for prostate cancer.  ...  Authors' contributions All authors were all involved in the conception and design of the project. All authors were involved in the data acquisition, analysis or interpretation.  ... 
doi:10.1186/s13014-014-0309-0 pmid:25889107 pmcid:PMC4340286 fatcat:jt5tiv5nsvh3zhpm4hcr6az24q

Cone-beam computerized tomography (CBCT) imaging of the oral and maxillofacial region: A systematic review of the literature

W. De Vos, J. Casselman, G.R.J. Swennen
2009 International Journal of Oral & Maxillofacial Surgery  
The results of this systematic review show that there is a lack of evidence-based data on the radiation dose for CBCT imaging.  ...  An attempt was made to provide a minimal set of CBCT device-related parameters for dedicated OMF scanners as a guideline for future studies.  ...  This group was broken down into 6 technical subcategories (Tables 6 and 7) . 28 (43%) papers evaluated the accuracy of CBCT imaging. 7 (37%) papers assessed the accuracy of general linear measurements  ... 
doi:10.1016/j.ijom.2009.02.028 pmid:19464146 fatcat:4nagsq3ykrg6fi4znsdnd3laoy

Brain Linac-Based Radiation Therapy: "Test Drive" of New Immobilization Solution and Surface Guided Radiation Therapy

Fabiana Gregucci, Ilaria Bonaparte, Alessia Surgo, Morena Caliandro, Roberta Carbonara, Maria Paola Ciliberti, Alberto Aga, Francesco Berloco, Marina De Masi, Christian De Pascali, Federica Fragnoli, Chiara Indellicati (+7 others)
2021 Journal of Personalized Medicine  
Aim: To test inter-fraction reproducibility, intrafraction stability, technician aspects, and patient/physician's comfort of a dedicated immobilization solution for Brain Linac-based radiation therapy  ...  Combining CBCT and SGRT data confirm that 1 mm CTV-PTV margin for Linac-based SRT was adequate. Using open-face mask and SGRT, for conventional RT, radiological imaging could be omitted.  ...  Combining CBCT and SGRT data, results confirm the accuracy of Linac-based RT. Using open-face mask and SGRT, for cRT, radiological imaging (portal or CBCT) could be omitted.  ... 
doi:10.3390/jpm11121351 pmid:34945823 pmcid:PMC8709255 fatcat:bw743qddyragvc4e52zdvo4tua

EP-2109: Novel verification technique for craniospinal irradiation with an image plate in the supine position

S.K. Ahn, S.K. Lee, J.H. Cho, C.O. Suh
2016 Radiotherapy and Oncology  
Conventionally fractionated (1.8 -2Gy/fraction, 139 pts) and moderately hypofractioned (2.35-2.65 Gy/fraction, 99 pts), step-andshoot IMRT (SS-IMRT, n=18), Volumetric Arc (RA IMRT, n=111) or helical tomotherapy  ...  Haematological toxicity (HT) in postprostatectomy patients (WPRT) treated with whole pelvis radiotherapy represents a problem due to the irradiation of a large fraction of the bone marrow (BM).  ...  The T test was used to assess differences between groups Results: From January to September 2015, 189 CBCT scans of 48 patients submitted to intracranial (39 scans) or extracranial (150 scans) Linac-based  ... 
doi:10.1016/s0167-8140(16)33360-6 fatcat:g3v5gtfwezfuze5kzcgadw5yda
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