Trends in radiation protection of positron emission tomography
... CT technology is used in PET/CT to perform AC and anatomical reference localisation for the PET scan data set. Low-resolution CT imaging using multi-slice CT scanners, usually 64-slice scanners, is usually requested. In CT imaging, proper selection of exposure parameters (e.g. kVp, mAs, scan length, ...
... CT technology is used in PET/CT to perform AC and anatomical reference localisation for the PET scan data set. Low-resolution CT imaging using multi-slice CT scanners, usually 64-slice scanners, is usually requested. In CT imaging, proper selection of exposure parameters (e.g. kVp, mAs, scan length, ...
Radiation Hygiene Requirements for IGRT (Image Guided
... stochastic effects (e.g. tumour induction) may be anticipated. It is also important to take into account those volumes which are exposed to a dose exceeding the tissue- or organ-specific radiation tolerance of the normal tissue within that volume but without clinical effects necessarily occurring; t ...
... stochastic effects (e.g. tumour induction) may be anticipated. It is also important to take into account those volumes which are exposed to a dose exceeding the tissue- or organ-specific radiation tolerance of the normal tissue within that volume but without clinical effects necessarily occurring; t ...
Technical assessment of a cone-beam CT scanner
... of the source and detector about the head, the peripheral dose varied at each of the measurement points (e.g., highest at the posterior point for short-scan orbits in which the source traverses the posterior of the head). In addition to the central absolute dose (Do ) the four peripheral dose measur ...
... of the source and detector about the head, the peripheral dose varied at each of the measurement points (e.g., highest at the posterior point for short-scan orbits in which the source traverses the posterior of the head). In addition to the central absolute dose (Do ) the four peripheral dose measur ...
Patient dose from kilovoltage cone beam computed tomography
... at any point in phantom would be proportional to the total technique settings 共mAs兲 and also to the in-air exposure rate at the reference point 共e.g., isocenter兲. Since different x-ray tubes may have different exposure rates 共mR/ mAs兲 and furthermore users may choose to use different numbers of proj ...
... at any point in phantom would be proportional to the total technique settings 共mAs兲 and also to the in-air exposure rate at the reference point 共e.g., isocenter兲. Since different x-ray tubes may have different exposure rates 共mR/ mAs兲 and furthermore users may choose to use different numbers of proj ...
The Measurement, Reporting, and Management of
... MDCT scanners utilize third-generation CT geometry in which an arc of detectors and the x-ray tube(s) rotate together. All MDCT scanners use a slip-ring gantry, allowing helical acquisition at rotation speeds as fast as 0.33 seconds for a full rotation of the x-ray tube about the isocenter17,18. The ...
... MDCT scanners utilize third-generation CT geometry in which an arc of detectors and the x-ray tube(s) rotate together. All MDCT scanners use a slip-ring gantry, allowing helical acquisition at rotation speeds as fast as 0.33 seconds for a full rotation of the x-ray tube about the isocenter17,18. The ...
Proceedings 6e Lustrum - Netherlands Commission on Radiation
... prescription, data entry, use of catheters or applicators. Some specific source positioning errors have been seen with the HDR afterloading techniques but different from LDR. Examples of such errors include applicator reconstruction errors, use of wrong applicator length or offset, wrong source step ...
... prescription, data entry, use of catheters or applicators. Some specific source positioning errors have been seen with the HDR afterloading techniques but different from LDR. Examples of such errors include applicator reconstruction errors, use of wrong applicator length or offset, wrong source step ...
ABDOMINAL EXAMINATION IN KNH USING 16 MULTI-SLICE
... tomography (CT scan). CT examinations are increasingly being employed in diagnostic procedures despite their high contribution to the total radiation dose (1). The skewed impact of CT radiation dose can be illustrated in Figure 1. According to UNSCEAR report of 2000, while only 5% of radiological ex ...
... tomography (CT scan). CT examinations are increasingly being employed in diagnostic procedures despite their high contribution to the total radiation dose (1). The skewed impact of CT radiation dose can be illustrated in Figure 1. According to UNSCEAR report of 2000, while only 5% of radiological ex ...
Radiological Protection in Paediatric Diagnostic and Interventional
... (7) Therefore, it is important for all patients, and particularly for infants and children, that all ...
... (7) Therefore, it is important for all patients, and particularly for infants and children, that all ...
Fluoroscopy and Radiation Safety Content for
... Exposure is the term used to express the intensity of energy produced by x‐ray equipment in air per unit time. When x‐rays travel through air, their interactions with the air molecules liberate electrons. If one collects these electrons and calculates the ratio of the electrons (Coulombs) to ma ...
... Exposure is the term used to express the intensity of energy produced by x‐ray equipment in air per unit time. When x‐rays travel through air, their interactions with the air molecules liberate electrons. If one collects these electrons and calculates the ratio of the electrons (Coulombs) to ma ...
Dose issues on multi-slice CT scanners
... generally contributes a greater percentage to the dose than that on a single slice scanner because the total collimated beam width is usually greater. This is shown diagrammatically in Figure 6 where the planned scanned length is equal for both the single and multi-slice scanner. When planning scan ...
... generally contributes a greater percentage to the dose than that on a single slice scanner because the total collimated beam width is usually greater. This is shown diagrammatically in Figure 6 where the planned scanned length is equal for both the single and multi-slice scanner. When planning scan ...
Incorporation of functional imaging data in the evaluation of dose
... distributions were evaluated using the generalized EUD and FEUD models with a lung a value of 0.96. Furthermore, a non-small cell lung cancer patient, who had previously received 3D external beam RT treatment at our institution, was inversely planned using the optimization algorithm of the PLUNC tre ...
... distributions were evaluated using the generalized EUD and FEUD models with a lung a value of 0.96. Furthermore, a non-small cell lung cancer patient, who had previously received 3D external beam RT treatment at our institution, was inversely planned using the optimization algorithm of the PLUNC tre ...
3D Dosimetry of the Amersham 6711 and AgX100 Iodine
... A. Thomas , J. Newton , M. Oldham. “A method to correct for stray light in telecentric optical‐CT imaging of radiochromic dosimeters”. (accessed Aug 2012) M. Oldham. “3D Dosimetry, and Clinically Meaningful QA” presentation. (accessed Aug 2012) R Popert, P Acher, N Nichol, S Morris, Ron Beaney. “B ...
... A. Thomas , J. Newton , M. Oldham. “A method to correct for stray light in telecentric optical‐CT imaging of radiochromic dosimeters”. (accessed Aug 2012) M. Oldham. “3D Dosimetry, and Clinically Meaningful QA” presentation. (accessed Aug 2012) R Popert, P Acher, N Nichol, S Morris, Ron Beaney. “B ...
Diagnostic Reference Levels Based on Latest Surveys in Japan
... 1. Background of Establishment of Diagnostic Reference Levels International guidelines, such as the recommendations and guidance published by the International Commission on Radiological Protection (ICRP) and International Basic Safety Standards published by the International Atomic Energy Agency ( ...
... 1. Background of Establishment of Diagnostic Reference Levels International guidelines, such as the recommendations and guidance published by the International Commission on Radiological Protection (ICRP) and International Basic Safety Standards published by the International Atomic Energy Agency ( ...
The World`s First Adaptive Scanner
... From the very beginning, one of the most frequent demands of our customers has been patient safety and in Computed Tomography. This translates primarily into dose reduction. For this reason, Siemens has developed many significant products and protocols that follow – even shape and redefine – the “As ...
... From the very beginning, one of the most frequent demands of our customers has been patient safety and in Computed Tomography. This translates primarily into dose reduction. For this reason, Siemens has developed many significant products and protocols that follow – even shape and redefine – the “As ...
Title Evaluation of radiation dose and image quality for the Varian
... a solid water phantom (Gammex RMI, Middleton, WI) against the absorbed dose determined by the 0.6-cc Farmer-type ionization chamber in air. All TLDs were irradiated three times to assign an individual sensitivity coefficient for the entire study. The positions of TLDs in the RANDO phantom were based ...
... a solid water phantom (Gammex RMI, Middleton, WI) against the absorbed dose determined by the 0.6-cc Farmer-type ionization chamber in air. All TLDs were irradiated three times to assign an individual sensitivity coefficient for the entire study. The positions of TLDs in the RANDO phantom were based ...
AAPM-RSNA Physics Tutorial for Residents: Typical Patient
... biologic effects. Absorbed dose is measured in units of gray (Gy) or milligray (mGy). One gray is equivalent to an energy deposition of 1 joule per kilogram (J/kg) of tissue. The outdated unit of absorbed dose is the rad, which equals 0.01 Gy. Absorbed dose rate is the amount of energy deposited in ...
... biologic effects. Absorbed dose is measured in units of gray (Gy) or milligray (mGy). One gray is equivalent to an energy deposition of 1 joule per kilogram (J/kg) of tissue. The outdated unit of absorbed dose is the rad, which equals 0.01 Gy. Absorbed dose rate is the amount of energy deposited in ...
University of Victoria Radiation Safety Refresher Course
... through matter, X-rays can be produced. • As the beta particle approaches the nucleus, the strong attractive forces cause a rapid change in direction, producing photon energy. ...
... through matter, X-rays can be produced. • As the beta particle approaches the nucleus, the strong attractive forces cause a rapid change in direction, producing photon energy. ...
Radiation Protection 109
... In accordance with the MED, DRLs should be established both for diagnostic radiology and for nuclear medicine, and if they are consistently exceeded investigation and appropriate corrective action should be taken. Therefore, in diagnostic radiology this level should be higher than the median or ...
... In accordance with the MED, DRLs should be established both for diagnostic radiology and for nuclear medicine, and if they are consistently exceeded investigation and appropriate corrective action should be taken. Therefore, in diagnostic radiology this level should be higher than the median or ...
Role of CTDI to estimate patient dose from a single slice to multi
... patient sizes from a newborn to a large adult, relative dose is exponentially related to patient size. There are several measures of radiation dose, each of which is used for a different purpose. The most readily available are dose indices known as the Volume Computed Tomography Dose Index (CTDIvol) ...
... patient sizes from a newborn to a large adult, relative dose is exponentially related to patient size. There are several measures of radiation dose, each of which is used for a different purpose. The most readily available are dose indices known as the Volume Computed Tomography Dose Index (CTDIvol) ...
CT Dose Reduction Applications - Journal of the American College
... kVp) with an appropriately adjusted mAs can still be of high diagnostic quality (particularly in thin patients) but at a substantially lower radiation dose. These studies have evaluated a wide variety of different CT examinations, including carotid CT angiography (CTA), coronary CTA, pulmonary CTA, ...
... kVp) with an appropriately adjusted mAs can still be of high diagnostic quality (particularly in thin patients) but at a substantially lower radiation dose. These studies have evaluated a wide variety of different CT examinations, including carotid CT angiography (CTA), coronary CTA, pulmonary CTA, ...
Y-90 SIRT in the Liver - Emory Radiology
... Let’s Start with SIR-Spheres at Most Basic Level: Empiric “Eyeball” Method A [GBq] = Liver Involvement Activity X LSM X LPM ...
... Let’s Start with SIR-Spheres at Most Basic Level: Empiric “Eyeball” Method A [GBq] = Liver Involvement Activity X LSM X LPM ...
Brachytherapy Treatment Plan QA Review
... Points of Interest/Critical Organ Localization • Localization of point A and B for T&O implants should be per institution protocol – Classic point A defined at 2 cm superior to vaginal fornices and 2 cm lateral from uterine canal – Modified point A definition at 2 cm superior to cervical os leads t ...
... Points of Interest/Critical Organ Localization • Localization of point A and B for T&O implants should be per institution protocol – Classic point A defined at 2 cm superior to vaginal fornices and 2 cm lateral from uterine canal – Modified point A definition at 2 cm superior to cervical os leads t ...
Adjusting kV to Improve Image Quality or Reduce Radiation Dose
... • 100 kV can be practically implemented already in most patients – Task-specific technique charts will include kV and mAs selection to perform most dose-efficient exam – 140 kV imaging may be most dose-efficient for large pts ...
... • 100 kV can be practically implemented already in most patients – Task-specific technique charts will include kV and mAs selection to perform most dose-efficient exam – 140 kV imaging may be most dose-efficient for large pts ...
Simple methods to reduce patient dose in a
... additional dose to the patient, a fact that has led to a recent report of task group 75 of the American Association of Physicists in Medicine [10]. In the case of daily CT scanning, the dose requires careful justification as it may be large, not only in the region of the target but also in the surro ...
... additional dose to the patient, a fact that has led to a recent report of task group 75 of the American Association of Physicists in Medicine [10]. In the case of daily CT scanning, the dose requires careful justification as it may be large, not only in the region of the target but also in the surro ...
Radiation Protection and Dose Monitoring in Medical
... on a number of variables, such as age, gender, region examined (the ankle is much less radiation-sensitive than the chest), and genetic susceptibility. The range of estimated additional risk for a fatal cancer is quite large, varying from approximately under 1 in 100 (1%, for a young patient and sev ...
... on a number of variables, such as age, gender, region examined (the ankle is much less radiation-sensitive than the chest), and genetic susceptibility. The range of estimated additional risk for a fatal cancer is quite large, varying from approximately under 1 in 100 (1%, for a young patient and sev ...