keyword
MENU ▼
Read by QxMD icon Read
search

Dosimetry

keyword
https://www.readbyqxmd.com/read/28647400/intraoperative-registered-ultrasound-and-fluoroscopy-iruf-for-dose-calculation-during-prostate-brachytherapy-improved-accuracy-compared-to-standard-ultrasound-based-dosimetry
#1
Junghoon Lee, Omar Y Mian, Yi Le, Hee Joon Bae, E Clif Burdette, Theodore L DeWeese, Jerry L Prince, Daniel Y Song
BACKGROUND AND PURPOSE: Intraoperative transrectal ultrasound dosimetry during low-dose-rate prostate brachytherapy is imprecise due to sonographic distortion caused by seed echoes and needle tracks that obscure seed positions or create false signals as well as traumatic edema. Here we report the results of a pilot study comparing a combined ultrasound and fluoroscopy-based seed localization method (iRUF) to standard ultrasound-based dosimetry (USD). MATERIAL AND METHODS: Eighty patients undergoing permanent Pd-103 seed implantation for prostate cancer were prospectively enrolled...
June 21, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28645838/sensitivity-analysis-and-uncertainty-quantification-in-pulmonary-drug-delivery-of-orally-inhaled-pharmaceuticals
#2
Jun Lu, Jinxiang Xi, Joseph E Langenderfer
In spite of widespread use of modeling tools in inhalation dosimetry, it remains difficult to quantify the output uncertainties when subjected to various sources of input variability. This study aimed to develop a computational model that can quantify the input sensitivity and output uncertainty in pulmonary drug delivery by coupling probabilistic analysis package NESSUS with ANSYS Fluent. An image-based mouth-lung model was used to simulate the transport and deposition of drug particles and variability in particle size, density, and inhalation speed were considered...
June 20, 2017: Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28644913/supplement-2-for-the-2004-update-of-the-aapm-task-group-no-43-report-joint-recommendations-by-the-aapm-and-gec-estro
#3
Mark J Rivard, Facundo Ballester, Wayne M Butler, Larry A DeWerd, Geoffrey S Ibbott, Ali S Meigooni, Christopher S Melhus, Michael G Mitch, Ravinder Nath, Panagiotis Papagiannis
Since publication of the 2004 update to the American Association of Physicists in Medicine (AAPM) Task Group No. 43 Report (TG-43U1) and its 2007 supplement (TG-43U1S1), several new low-energy photon-emitting brachytherapy sources have become available. Many of these sources have satisfied the AAPM prerequisites for routine clinical purposes and are posted on the Brachytherapy Seed Registry managed jointly by the AAPM and the Imaging and Radiation Oncology Core Houston Quality Assurance Center (IROC Houston)...
June 23, 2017: Medical Physics
https://www.readbyqxmd.com/read/28644800/online-combination-of-epid-cherenkov-imaging-for-3d-dosimetry-in-a-liquid-phantom
#4
Petr Bruza, Jacqueline M Andreozzi, David J Gladstone, Lesley A Jarvis, Joerg Rottmann, Brian W Pogue
Online acquisition of Cherenkov and portal imaging data was combined with a reconstruction scheme called EC3D, providing a full 3D dosimetry of megavoltage X-ray beams in a water tank. The methodology was demonstrated and quantified in a single static beam. Furthermore, the dynamics and visualization of the 3D dose reconstruction were demonstrated with a volumetric modulated arc therapy (VMAT) plan for TG-119 C-Shape geometry. The developed algorithm combines depth dose information, provided by Cherenkov images, with the lateral dose distribution, provided by the electronic portal imaging device (EPID)...
June 20, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28643752/dosimetric-characterization-of-optically-stimulated-luminescence-dosimeter-with-therapeutic-photon-beams-for-use-in-clinical-radiotherapy-measurements
#5
Retna Ponmalar, Ravikumar Manickam, K M Ganesh, Sathiyan Saminathan, Arun Raman, Henry Finlay Godson
AIM: The modern radiotherapy techniques impose new challenges for dosimetry systems with high precision and accuracy in in vivo and in phantom dosimetric measurements. The knowledge of the basic characterization of a dosimetric system before patient dose verification is crucial. This incites the investigation of the potential use of nanoDot optically stimulated luminescence dosimeter (OSLD) for application in radiotherapy with therapeutic photon beams. MATERIALS AND METHODS: Measurements were carried out with nanoDot OSLDs to evaluate the dosimetric characteristics such as dose linearity, dependency on field size, dose rate, energy and source-to-surface distance (SSD), reproducibility, fading effect, reader stability, and signal depletion per read out with cobalt-60 (60 Co) beam, 6 and 18 MV therapeutic photon beams...
April 2017: Journal of Cancer Research and Therapeutics
https://www.readbyqxmd.com/read/28643730/an-overview-on-small-field-dosimetry-in-photon-beam-radiotherapy-developments-and-challenges
#6
REVIEW
Hamed Bagheri, Azadeh Soleimani, Nahideh Gharehaghaji, Asghar Mesbahi, Farhad Manouchehri, Babak Shekarchi, Banafsheh Dormanesh, Habib Alah Dadgar
Small fields are more repeatedly used for radiation therapy as small segments in intensity-modulated radiotherapy or as in the form of independent fields in stereotactic radiosurgery and other novel equipment such as cyberknife and tomotherapy. Nevertheless, the application of small fields for radiotherapy of lung makes the dose calculation and planning inaccurate due to the existence of electronic disequilibrium and intrinsic deficiencies within most of the analytical dose calculation algorithms. The current review attempts to gather the information in this regard and focuses on the current progresses and retaining issues associated with this type of photon beams...
April 2017: Journal of Cancer Research and Therapeutics
https://www.readbyqxmd.com/read/28641969/determining-3d-kinematics-of-the-hip-using-video-fluoroscopy-guidelines-for-balancing-radiation-dose-and-registration-accuracy
#7
Fabio D'Isidoro, Patrik Eschle, Thomas Zumbrunn, Christian Sommer, Stephan Scheidegger, Stephen J Ferguson
BACKGROUND: Video fluoroscopy is a technique currently used to retrieve the in vivo three-dimensional kinematics of human joints during activities of daily living. Minimization of the radiation dose absorbed by the subject during the measurement is a priority and has not been thoroughly addressed so far. This issue is critical for the motion analysis of the hip joint, because of the proximity of the gonads. The aims of this study were to determine the x-ray voltage and the irradiation angle that minimize the effective dose and to achieve the best compromise between delivered dose and accuracy in motion retrieval...
May 25, 2017: Journal of Arthroplasty
https://www.readbyqxmd.com/read/28641204/towards-dosimetry-for-photodynamic-diagnosis-with-the-low-level-dose-of-photosensitizer
#8
Igor Buzalewicz, Iwona Hołowacz, Agnieszka Ulatowska-Jarża, Halina Podbielska
BACKGROUND: Contemporary medicine does not concern the issue of dosimetry in photodynamic diagnosis (PDD) but follows the photosensitizer (PS) producers recommendation. Most preclinical and clinical PDD studies indicate a considerable variation in the possibility of visualization and treatment, as e.g. in case of cervix lesions. Although some of these variations can be caused by the different histological subtypes or various tumor geometries, the issue of varying PS concentration in the tumor tissue volume is definitely an important factor...
June 15, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28639942/commissioning-of-the-tongue-and-groove-modelling-in-treatment-planning-systems-from-static-fields-to-vmat-treatments
#9
Victor Hernandez, Juan Antonio Vera-Sánchez, Laure Vieillevigne, Jordi Saez
Adequate modelling of the multi-leaf collimator (MLC) by treatment planning systems (TPS) is essential for accurate dose calculations in intensity-modulated radiation-therapy. For this reason modern TPSs incorporate MLC characteristics such as the leaf end curvature, MLC transmission and the tongue-and-groove. However, the modelling of the tongue-and-groove is often neglected during TPS commissioning and it is not known how accurate it is. This study evaluates the dosimetric consequences of the tongue-and-groove effect for two different MLC models using both film dosimetry and ionisation chambers...
June 22, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28637800/pharmacokinetics-biodistribution-and-radiation-dosimetry-for-89-zr-trastuzumab-in-patients-with-esophagogastric-cancer
#10
Joseph A O'Donoghue, Jason S Lewis, Neeta Pandit-Taskar, Stephen E Fleming, Heiko Schoder, Steven M Larson, Volkan Beylergil, Shutian Ruan, Serge Lyashchenko, Pat B Zanzonico, Wolfgang Andreas Weber, Jorge A Carrasquillo, Yelena Y Janjigian
Trastuzumab with chemotherapy improves clinical outcomes in patients with human epidermal growth factor receptor 2 (HER2)-positive esophagogastric adenocarcinoma (EGA). Despite the therapeutic benefit, responses are rarely complete and the majority of patients develop progression. This is the first report evaluating (89)Zr-trastuzumab in HER2-positive EGA in which we evaluate the safety, pharmacokinetics, biodistribution, and dosimetry. Methods: Trastuzumab was conjugated with deferoxamine and radiolabeled with (89)Zr...
June 21, 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/28636805/a-hybrid-phantom-system-for-patient-skin-and-organ-dosimetry-in-fluoroscopically-guided-interventions
#11
David Borrego, Daniel Siragusa, Stephen Balter, Wesley E Bolch
To investigate calibrations for improved estimates of skin dose and to develop software for computing absorbed organ doses for fluoroscopically guided interventions (FGIs) with the use of radiation dose structured reports (RDSR) and the UF/NCI family of hybrid computational phantoms METHODS AND MATERIALS: Institutional review board approval was obtained for this retrospective study in which ten RDSRs were selected for their high cumulative reference air kerma values. Skin doses were computed using the University of Florida's rapid in-clinic peak skin dose algorithm (or UF-RIPSA)...
June 21, 2017: Medical Physics
https://www.readbyqxmd.com/read/28636564/radiation-dosimetry-in-magnetic-fields-with-farmer-type-ionization-chambers-determination-of-magnetic-field-correction-factors-for-different-magnetic-field-strengths-and-field-orientations
#12
Claudia Katharina Spindeldreier, Oliver Schrenk, Anna Bakenecker, Iwan Kawrakow, Lucas Norberto Burigo, Christian P Karger, Steffen Greilich, Asja Pfaffenberger
The aim of this work was to determine magnetic field correction factors that are needed for dosimetry in hybrid devices for MR-guided radiotherapy for Farmer-type ionization chambers for different magnetic field strengths and field orientations. The response of six custom-built Farmer-type chambers irradiated at a 6 MV linac was measured in a water tank positioned in a magnet with magnetic field strengths between 0.0 T and 1.1 T. Chamber axis, beam and magnetic field were perpendicular to each other and both magnetic field directions were investigated...
June 21, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28633957/displacement-patterns-of-stranded-i-125-seeds-after-permanent-brachytherapy-of-the-prostate-dosimetry-in-the-operating-room-put-into-perspective
#13
Marcel J Steggerda, Ferrie van den Boom, Thelma Witteveen, Luc M F Moonen
BACKGROUND AND PURPOSE: The reliability of post-implant dosimetry in the OR depends on the geometrical variability of implant and anatomy after the procedure. The purpose was to gain detailed information on seed displacement patterns in different sectors of the prostate. MATERIALS AND METHODS: Of 33 patients with stranded seed implants the seed geometry and the dose distribution were compared between the situation in the OR just after the procedure, based on ultrasound images, and the situation after 1month, based on registered CT and MR images...
June 17, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28633133/optically-stimulated-luminescence-study-in-rare-earth-doped-srbpo5
#14
Sonali Gaikwad, R R Patil, M S Kulkarni, S V Moharil
Optically stimulated luminescence (OSL) was studied in rare earth doped SrBPO5 for the possible applications in radiation dosimetry using optically stimulated luminescence. The study shows that the sensitivity of the Eu doped SrBPO5 shows good OSL and the sensitivity is comparable to that of Al2O3:C. It is observed that annealing has a profound effect on the OSL sensitivity. Slowly cooled Eu doped sample shows highest sensitivity and is 77% compared to that Al2O3:C whereas lowest sensitivity is observed in the quenched sample...
June 9, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28628784/identifying-populations-sensitive-to-environmental-chemicals-by-simulating-toxicokinetic-variability
#15
Caroline L Ring, Robert G Pearce, R Woodrow Setzer, Barbara A Wetmore, John F Wambaugh
The thousands of chemicals present in the environment (USGAO, 2013) must be triaged to identify priority chemicals for human health risk research. Most chemicals have little of the toxicokinetic (TK) data that are necessary for relating exposures to tissue concentrations that are believed to be toxic. Ongoing efforts have collected limited, in vitro TK data for a few hundred chemicals. These data have been combined with biomonitoring data to estimate an approximate margin between potential hazard and exposure...
June 16, 2017: Environment International
https://www.readbyqxmd.com/read/28628155/-3d-printed-template-assisted-and-computed-tomography-image-guided-125-iodine-seed-implantation-for-supraclavicular-metastatic-tumor-a-dosimetric-study
#16
(no author information available yet)
OBJECTIVE: To compare the dosimetric data between the preoperative plans and postoperative verification in personalized 3D printed template-assisted and computed tomography (CT) image-guided 125-iodine seed implantation for supraclavicular metastatic tumor, and to evaluate the accuracy and feasibility at the dosimetry level. METHODS: A total of 14 patients with supraclavicular metastatic tumor (including 15 lesions) who received 3D printed template assisted and CT image-guided 125-iodine seed implantation in Department of Radiation Oncology of Peking University Third Hospital from January to September 2016 were enrolled...
June 18, 2017: Beijing da Xue Xue Bao. Yi Xue Ban, Journal of Peking University. Health Sciences
https://www.readbyqxmd.com/read/28625472/3d-catheter-reconstruction-in-hdr-prostate-brachytherapy-for-pre-treatment-verification-using-a-flat-panel-detector
#17
Ryan L Smith, Annette Haworth, Vanessa Panettieri, Jeremy L Millar, Rick D Franich
PURPOSE: High dose rate prostate brachytherapy is a widely-practiced treatment, delivering large conformal doses in relatively few treatment fractions. Inter- and intra-fraction catheter displacements have been reported. Unrecognized displacement can have a significant impact on dosimetry. Knowledge of the implant geometry at the time of treatment is important for ensuring safe and effective treatment. In this work we demonstrate a method to reconstruct the catheter positions pre-treatment, using a 'shift' imaging technique, and perform registration with the treatment plan for verification relative to the prostate...
June 15, 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28624329/the-bebig-valencia-type-skin-applicators-dosimetric-study-and-implementation-of-a-dosimetric-hybrid-technique
#18
Georgios Anagnostopoulos, Michael Andrássy, Dimos Baltas
PURPOSE: To determine the relative dose rate distribution in water for the Bebig 20 mm and 30 mm skin applicators and report results in a form suitable for potential clinical use. Results for both skin applicators are also provided in the form of a hybrid Task Group 43 (TG-43) dosimetry technique. Furthermore, the radiation leakage around both skin applicators from the radiation protection point of view and the impact of the geometrical source position uncertainties are studied and reported...
June 14, 2017: Brachytherapy
https://www.readbyqxmd.com/read/28622770/intensity-modulated-radiation-therapy-from-70gy-to-80gy-in-prostate-cancer-six-year-outcomes-and-predictors-of-late-toxicity
#19
Maria Jolnerovski, Julia Salleron, Véronique Beckendorf, Didier Peiffert, Anne-Sophie Baumann, Valérie Bernier, Sandrine Huger, Vincent Marchesi, Ciprian Chira
OBJECTIVE: To report grade ≥2 overall late rectal and urinary toxicities in patients (pts) with prostate cancer treated by intensity-modulated radiotherapy (IMRT) at 3 dose-levels. Identify predictors of radiation toxicity and report biochemical progression free survival (bPFS). METHODS: A total of 277 pts were treated with 70Gy (10.8%), 74Gy (63.9%) and 80 Gy (25.3%) using IMRT without pelvic irradiation were analyzed. Short or long-course androgen deprivation therapy (ADT) was allowed in 46...
June 16, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28621586/the-cooler-code-a-novel-analytical-approach-to-calculate-subcellular-energy-deposition-by-internal-electron-emitters
#20
Mattia Siragusa, Giorgio Baiocco, Pil M Fredericia, Werner Friedland, Torsten Groesser, Andrea Ottolenghi, Mikael Jensen
COmputation of Local Electron Release (COOLER), a software program designed for dosimetry assessment at the cellular/subcellular scale, with a given distribution of administered low-energy electron-emitting radionuclides in cellular compartments, which remains a critical step in risk/benefit analysis for advancements in internal radiotherapy. The software is intended to overcome the main limitations of the medical internal radiation dose (MIRD) formalism for calculations of cellular S-values (i.e., dose to a target region in the cell per decay in a given source region), namely, the use of the continuous slowing down approximation (CSDA) and the assumption of a spherical cell geometry...
June 16, 2017: Radiation Research
keyword
keyword
60683
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"