keyword
MENU ▼
Read by QxMD icon Read
search

Radiation dose measurements

keyword
https://www.readbyqxmd.com/read/28548280/air-core-detectors-for-cerenkov-free-scintillation-dosimetry-of-brachytherapy-%C3%AE-sources
#1
Marion Eichmann, Benedikt Thomann
PURPOSE: Plastic scintillation detectors are used for dosimetry in small radiation fields with high dose gradients, green e.g. provided by β-emitting sources like (106) Ru/(106) Rh eye plaques. A drawback is a background signal caused by Cerenkov radiation generated by electrons passing the optical fibers (light guides) of this dosimetry system. Common approaches to correct for the Cerenkov signal are influenced by uncertainties resulting from detector positioning and calibration procedures...
May 26, 2017: Medical Physics
https://www.readbyqxmd.com/read/28545887/how-to-identify-high-radiation-burden-from-computed-tomography-an-example-in-obese-children
#2
Daniel L Lodwick, Jennifer N Cooper, Brent Adler, Choonsik Lee, Kelly Kelleher, Peter C Minneci, Katherine J Deans
BACKGROUND: Radiation burden from the use of computed tomography (CT) imaging may not be evenly distributed. We tested whether overweight and obese children receive higher radiation burden from CT imaging. METHODS: An automated software tool (DoseWizard) assessed patient-level radiation dose from CT and merged results with clinical data from the electronic health record. CT scans of the head, chest, and abdomen/pelvis (A/P) performed at our institution from January 2013 to August 2015 on patients aged <16 y were processed using this software...
May 5, 2017: Journal of Surgical Research
https://www.readbyqxmd.com/read/28545264/reduction-of-dose-to-the-contralateral-breast-by-superflab-use-in-radiation-therapy-for-mammary-carcinomas
#3
Akanksha Solanki, Athiyaman M, Hemalatha A, H S Kumar
Background: Radiation therapy is an integral part of multimodality treatment for locally advanced carcinoma of breast. Radiation doses to nearby critical normal structures like heart, lungs, and contralateral breast (CLB increases risk of second malignancies. In this study, we measured doses to the CLB and studied effects of a 1 cm thickness superflap. Materials and Methods: Fifty post-mastectomy carcinoma breast patients were included in the study.Radiation therapy of 50 Gy was planned in 25 fractions, 5 days a week, using the Eclipse Treatment Planning System version 8...
April 1, 2017: Asian Pacific Journal of Cancer Prevention: APJCP
https://www.readbyqxmd.com/read/28545190/radiation-exposure-in-patients-with-inflammatory-bowel-disease-a-fourteen-year-review-at-a-tertiary-care-centre-in-malaysia
#4
Jeevinesh Naidu, Zhiqin Wong, Shanthi Palaniappan, Chai Soon Ngiu, Raja Affendi Raja Ali
Background and Aims: Patients with inflammatory bowel disease (IBD) are subjected to a large amount of ionizing radiation during the course of their illness. This may increase their risk of malignancy to a greater level than that due to the disease itself. In Caucasian patients with Crohn’s disease, this has been well documented and recommendations are in place to avoid high radiation imaging protocols. However, there are limited data available on radiation exposure in Asian IBD patients.We therefore sought to identify total radiation exposure and any differences between ethnically diverse ulcerative colitis (UC) and Crohn’s disease (CD) patients at our centre along with determining factors that may contribute to any variation...
April 1, 2017: Asian Pacific Journal of Cancer Prevention: APJCP
https://www.readbyqxmd.com/read/28544977/environmental-radiation-dosimetry-at-argentine-antarctic-marambio-base-64%C3%A2-13-s-56%C3%A2-43-w-preliminary-results
#5
Alba Zanini, Vicente Ciancio, Monica Laurenza, Marisa Storini, Adolfo Esposito, Juan Carlos Terrazas, Paolo Morfino, Alessandro Liberatore, Gustavo Di Giovan
The preliminary results obtained in the first environmental radiation dosimetry campaign performed in the Antarctic region are presented. This experiment is carried out in the framework of CORA (COsmic Rays in Antarctica) Project, a collaboration between Argentine and Italian institutions. After a feasibility study performed in the Antarctic summer 2013, a new campaign has been carried out, started in March 2015, to measure various components of cosmic ray induced secondary atmospheric radiation at the Argentine Marambio Base (Antarctica; 196 m a...
May 22, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28542006/an-efficient-affordable-optically-stimulated-luminescent-osl-annealer
#6
Sara A Abraham, Samuel J Frank, Kimberlee J Kearfott
Optically stimulated luminescent (OSL) dosimeters are devices used for measuring doses of ionizing radiation. Signal is stored within an OSL material so that when stimulated with light, light of a specific wavelength is emitted in proportion to the integrated ionizing radiation dose. Each interrogation of the material results in the loss of a small fraction of signal, thus allowing multiple interrogations leading to more accurate measurements of dose. In order to reuse a dosimeter, the residual signals from prior doses must be taken into account and subtracted from current readings, adding uncertainty to any future measurements...
July 2017: Health Physics
https://www.readbyqxmd.com/read/28540813/measurement-and-analysis-of-the-impact-of-time-interval-temperature-and-radiation-dose-on-tumour-cell-survival-and-its-application-in-thermoradiotherapy-plan-evaluation
#7
C M van Leeuwen, A L Oei, R Ten Cate, N A P Franken, A Bel, L J A Stalpers, J Crezee, H P Kok
PURPOSE: Biological modelling of thermoradiotherapy may further improve patient selection and treatment plan optimisation, but requires a model that describes the biological effect as a function of variables that affect treatment outcome (e.g. temperature, radiation dose). This study aimed to establish such a model and its parameters. Additionally, a clinical example was presented to illustrate the application. METHODS: Cell survival assays were performed at various combinations of radiation dose (0-8 Gy), temperature (37-42 °C), time interval (0-4 h) and treatment sequence (radiotherapy before/after hyperthermia) for two cervical cancer cell lines (SiHa and HeLa)...
May 9, 2017: International Journal of Hyperthermia
https://www.readbyqxmd.com/read/28537771/atmospheric-constraints-on-the-surface-uv-environment-of-mars-at-3-9%C3%A2-ga-relevant-to-prebiotic-chemistry
#8
Sukrit Ranjan, Robin Wordsworth, Dimitar D Sasselov
Recent findings suggest that Mars may have been a clement environment for the emergence of life and may even have compared favorably to Earth in this regard. These findings have revived interest in the hypothesis that prebiotically important molecules or even nascent life may have formed on Mars and been transferred to Earth. UV light plays a key role in prebiotic chemistry. Characterizing the early martian surface UV environment is key to understanding how Mars compares to Earth as a venue for prebiotic chemistry...
May 24, 2017: Astrobiology
https://www.readbyqxmd.com/read/28536392/personalized-dosimetry-for-radionuclide-therapy-using-molecular-imaging-tools
#9
REVIEW
Michael Ljungberg, Katarina Sjögreen Gleisner
For treatment of systemic malignancies, when external radiation therapy is not applicable, radionuclide therapy can be an alternative. In this form of therapy, radionuclides are administered to the patient, often in a form where the radionuclide is labelled to a molecule that plays the active part in the localization of the tumor. Since the aim is to impart lethal damage to tumor cells while maintaining possible side-effects to normal tissues at tolerable levels, a proper and accurate personalized dosimetry should be a pre-requisite...
November 15, 2016: Biomedicines
https://www.readbyqxmd.com/read/28535918/polymer-gel-dosimeters-for-pretreatment-radiotherapy-verification-using-the-three-dimensional-gamma-evaluation-and-pass-rate-maps
#10
Ling-Ling Hsieh, Jiunn-I Shieh, Li-Ju Wei, Yi-Chun Wang, Kai-Yuan Cheng, Cheng-Ting Shih
Polymer gel dosimeters (PGDs) have been widely studied for use in the pretreatment verification of clinical radiation therapy. However, the readability of PGDs in three-dimensional (3D) dosimetry remain unclear. In this study, the pretreatment verifications of clinical radiation therapy were performed using an N-isopropyl-acrylamide (NIPAM) PGD, and the results were used to evaluate the performance of the NIPAM PGD on 3D dose measurement. A gel phantom was used to measure the dose distribution of a clinical case of intensity-modulated radiation therapy...
May 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28535914/does-gantry-rotation-time-influence-accuracy-of-volume-computed-tomography-dose-index-ctdivol-in-modern-ct
#11
Atsushi Fukuda, Nao Ichikawa, Yoshiharu Fujita, Pei-Jan Paul Lin, Kosuke Matsubara, Tosiaki Miyati
PURPOSE: The purpose of this study was to develop a gantry overrun corrected CTDIvol (cCTDIvol) dosimetry and evaluate the differences between the displayed CTDIvol (dCTDIvol), measured CTDIvol (mCTDIvol), and the cCTDIvol. METHODS AND MATERIALS: The each 8 rotation times between 275 and 1000ms of two CT scanners were investigated. Rotation time (Trot) and the beam-on time (Tbeam) in axial scanning were measured accurately to determine the gantry overrun time (Tover) as Tbeam-Trot...
May 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28535913/patient-doses-and-occupational-exposure-in-a-hybrid-operating-room
#12
C Andrés, H Pérez-García, M Agulla, R Torres, D Miguel, A Del Castillo, C M Flota, D Alonso, J de Frutos, C Vaquero
PURPOSE: This study aimed to characterize the radiation exposure to patients and workers in a new vascular hybrid operating room during X-ray-guided procedures. METHODS: During one year, data from 260 interventions performed in a hybrid operating room equipped with a Siemens Artis Zeego angiography system were monitored. The patient doses were analysed using the following parameters: radiation time, kerma-area product, patient entrance reference point dose and peak skin dose...
May 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28534155/myocardial-delayed-enhancement-ct-initial-experience-in-children-and-young-adults
#13
Hyun Woo Goo
BACKGROUND: Clinical utility of myocardial delayed enhancement CT has not been reported in children and young adults. OBJECTIVE: To describe initial experience of myocardial delayed enhancement CT regarding image quality, radiation dose and identification of myocardial lesions in children and young adults. MATERIALS AND METHODS: Between August 2013 and November 2016, 29 consecutive children and young adults (median age 16 months) with suspected coronary artery or myocardial abnormality underwent arterial- and delayed-phase cardiac CT at our institution...
May 23, 2017: Pediatric Radiology
https://www.readbyqxmd.com/read/28534154/chemoradiation-impairs-normal-developmental-cortical-thinning-in-medulloblastoma
#14
Palak Kundu, Matthew D Li, Ben Y Durkee, Susan M Hiniker, Karl Bush, Rie von Eyben, Michelle L Monje, Kristen W Yeom, Sarah S Donaldson, Iris C Gibbs
Medulloblastoma patients are treated with surgery, radiation and chemotherapy. Radiation dose to the temporal lobe may be associated with neurocognitive sequelae. Longitudinal changes of temporal lobe cortical thickness may result from neurodevelopmental processes such as synaptic pruning. This study applies longitudinal image analysis to compare developmental change in cortical thickness in medulloblastoma (MB) patients who were treated by combined modality therapy to that of cerebellar juvenile pilocytic astrocytoma (JPA) patients who were treated by surgery alone...
May 22, 2017: Journal of Neuro-oncology
https://www.readbyqxmd.com/read/28533634/estimation-of-whole-body-radiation-exposure-to-nuclear-medicine-personnel-during-synthesis-of-177-lutetium-labeled-radiopharmaceuticals
#15
Geetanjali Arora, Rajesh Mishra, Praveen Kumar, Madhav Yadav, Sanjana Ballal, Chandrasekhar Bal, Nishikant Avinash Damle
PURPOSE OF THE STUDY: With rapid development in the field of nuclear medicine therapy, radiation safety of the personnel involved in synthesis of radiopharmaceuticals has become imperative. Few studies have been done on estimating the radiation exposure of personnel involved in the radio labeling of (177)Lu-compounds in western countries. However, data from the Indian subcontinent are limited. We have estimated whole body radiation exposure to the radiopharmacist involved in the labeling of: (177)Lu-DOTATATE, (177)Lu-PSMA-617, and (177)Lu-EDTMP...
April 2017: Indian Journal of Nuclear Medicine: IJNM: the Official Journal of the Society of Nuclear Medicine, India
https://www.readbyqxmd.com/read/28533474/weekly-low-dose-versus-three-weekly-high-dose-cisplatin-for-concurrent-chemoradiation-in-locoregionally-advanced-non-nasopharyngeal-head-and-neck-cancer-a-systematic-review-and-meta-analysis-of-aggregate-data
#16
Petr Szturz, Kristien Wouters, Naomi Kiyota, Makoto Tahara, Kumar Prabhash, Vanita Noronha, Ana Castro, Lisa Licitra, David Adelstein, Jan B Vermorken
BACKGROUND: Three-weekly high-dose cisplatin (100 mg/m(2)) is considered the standard systemic regimen given concurrently with postoperative or definitive radiotherapy in locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN). However, due to unsatisfactory patient tolerance, various weekly low-dose schedules have been increasingly used in clinical practice. The aim of this meta-analysis was to compare the efficacy, safety, and compliance between these two approaches...
May 22, 2017: Oncologist
https://www.readbyqxmd.com/read/28529251/image-quality-and-clinical-usefulness-of-ray-summation-image-reconstructed-from-ct-data-compared-with-digital-radiography
#17
Shogo Suzuki, Katsuhiro Ichikawa, Shigeru Tamaki
Ray-summation (raysum) images reconstructed from computed tomography (CT) volume data resemble digital radiography (DR) images. Therefore, they have a potential to be used instead of DR images.The aim of this study was to compare the physical image quality evaluated by signal-difference-to-noise ratio (SDNR) and clinical usefulness between raysum and DR images. We employed an oval water phantom simulating adult abdomen for image quality measurement. Raysum images were reconstructed from CT volume data using an assumed x-ray quality of 70 keV...
2017: Nihon Hoshasen Gijutsu Gakkai Zasshi
https://www.readbyqxmd.com/read/28529250/impact-of-jaw-position-accuracy-on-dose-variation-in-volumetric-modulated-arc-therapy-using-jaw-tracking
#18
Fumiyasu Matsubayashi, Yuki Koizumi, Ryo Takahashi, Minoru Yoshioka, Tomoharu Sato
The technique of jaw tracking can be used in volumetric modulated arc therapy (VMAT) and intensity modulated radiation therapy (IMRT). In this technique, jaw tracks apertures of the multi leaf collimator (MLC) during irradiation. It is reported that dose variation is occurred by the changing accuracy of MLC position in VMAT and IMRT. Though jaw moves dynamically in the irradiation by using this technique, the influence of the jaw position accuracy on dose variation is not examined. The purpose of this study is to verify the influence of jaw position accuracy on dose variation in VMAT using jaw tracking...
2017: Nihon Hoshasen Gijutsu Gakkai Zasshi
https://www.readbyqxmd.com/read/28528206/feasibility-of-atlas-based-active-bone-marrow-sparing-intensity-modulated-radiation-therapy-for-cervical-cancer
#19
Nan Li, Sonal S Noticewala, Casey W Williamson, Hanjie Shen, Igor Sirak, Rafal Tarnawski, Umesh Mahantshetty, Carl K Hoh, Kevin L Moore, Loren K Mell
BACKGROUND: To test the hypothesis that atlas-based active bone marrow (ABM)-sparing intensity modulated radiation therapy (IMRT) yields similar dosimetric results compared to custom ABM-sparing IMRT for cervical cancer patients. METHODS: We sampled 62 cervical cancer patients with pre-treatment FDG-PET/CT in training (n=32) or test (n=30) sets. ABM was defined as the subvolume of the pelvic bone marrow (PBM) with standardized uptake value (SUV) above the mean on the average FDG-PET image (ABMAtlas) vs...
May 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28527605/analysis-of-gafchromic-ebt3-film-calibration-irradiated-with-gamma-rays-from-different-systems-gamma-knife-and-cobalt-60-unit
#20
Monsen Najafi, Ghazale Geraily, Alireza Shirazi, Mahbod Esfahani, Javad Teimouri
In recent years, Gafchromic films are used as an advanced instrument for dosimetry systems. The EBT3 films are a new generation of Gafchromic films. Our main interest is to compare the response of the EBT3 films exposed to gamma rays provided by the Theratron 780C as a conventional radiotherapy system and the Leksell Gamma Knife as a stereotactic radiotherapy system (SRS). Both systems use Cobalt-60 sources, thus using the same energy. However, other factors such as source-to-axis distance, number of sources, dose rate, direction of irradiation, shape of phantom, the field shape of radiation, and different scatter contribution may influence the calibration curve...
May 17, 2017: Medical Dosimetry: Official Journal of the American Association of Medical Dosimetrists
keyword
keyword
6437
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"