Radiation dose reduction in computed tomography
... Quantifying CT radiation dose & associated risk Radiation dose in CT can be quantified in a variety of ways. Scanner radiation output, organ dose and effective dose are several of the more common dose metrics. The scanner radiation output is currently represented by the volume CT dose index (CTDIvol ...
... Quantifying CT radiation dose & associated risk Radiation dose in CT can be quantified in a variety of ways. Scanner radiation output, organ dose and effective dose are several of the more common dose metrics. The scanner radiation output is currently represented by the volume CT dose index (CTDIvol ...
Innova X-ray Dose Efficiency: Objective Evidence
... complications of decreased heart function, and decreased quality of life. Pediatric interventions are an important case of stochastic risk, since the likelihood of cancer expression may increase with lifetime following exposure, and the young are generally considered more sensitive to radiation expo ...
... complications of decreased heart function, and decreased quality of life. Pediatric interventions are an important case of stochastic risk, since the likelihood of cancer expression may increase with lifetime following exposure, and the young are generally considered more sensitive to radiation expo ...
Applied Physics Radiation Oncology
... Treatment planning includes visualization, localization, field selection and placement, and verification. Visualization is the determination of the location and extent of the tumor, particularly with respect to anatomical landmarks. This process uses every reasonable method of examination, including ...
... Treatment planning includes visualization, localization, field selection and placement, and verification. Visualization is the determination of the location and extent of the tumor, particularly with respect to anatomical landmarks. This process uses every reasonable method of examination, including ...
19 2D and 3D Planning in Brachytherapy
... valid for the dose calculation and evaluation. A common procedure, at least in the past for gynaecological and other intracavitary applications, was based on two or more X-ray films, which are mainly used for the 3D reconstruction of the used catheters or applicators. For the intracavitary brachyther ...
... valid for the dose calculation and evaluation. A common procedure, at least in the past for gynaecological and other intracavitary applications, was based on two or more X-ray films, which are mainly used for the 3D reconstruction of the used catheters or applicators. For the intracavitary brachyther ...
01 - Use of a dDVH decomposition technique to evaluate
... multimodality medical image registration and treatment application to provide superior accuracy and reproducibility. The recent advent of frameless techniques for the registration of medical images and their accuracy assesment foster the use of multimodal information in radiotherapy and radiosurgery ...
... multimodality medical image registration and treatment application to provide superior accuracy and reproducibility. The recent advent of frameless techniques for the registration of medical images and their accuracy assesment foster the use of multimodal information in radiotherapy and radiosurgery ...
Patient Dose in common CT examinations-2003
... data from a wide scale survey. Therefore, it is of great interest whether there are dose quantities whose values are easy to obtain, which can correctly reflect the patient dose and allow assessment of the risk associated with the CT examination. The most widely used CT Dose Quantity is the computed ...
... data from a wide scale survey. Therefore, it is of great interest whether there are dose quantities whose values are easy to obtain, which can correctly reflect the patient dose and allow assessment of the risk associated with the CT examination. The most widely used CT Dose Quantity is the computed ...
ICRP PUBLICATION 121: Radiological Protection in Paediatric
... purpose. Reducing doses to reduce detriment to the patient is sensible but, for example, reducing computed tomography doses such that the image no longer gives the necessary diagnostic information, or therapeutic doses such that the procedure is not sufficiently efficacious, is contrary to good medical ...
... purpose. Reducing doses to reduce detriment to the patient is sensible but, for example, reducing computed tomography doses such that the image no longer gives the necessary diagnostic information, or therapeutic doses such that the procedure is not sufficiently efficacious, is contrary to good medical ...
PDF - Thieme Connect
... values or diagnostic reference levels did not exist. For the first time, the International Commission on Radiological Protection (ICRP) recommended the application of dose reference levels in 1996 [3]. A year later, EURATOM (European Atomic Energy Community), which likewise addresses the requirement ...
... values or diagnostic reference levels did not exist. For the first time, the International Commission on Radiological Protection (ICRP) recommended the application of dose reference levels in 1996 [3]. A year later, EURATOM (European Atomic Energy Community), which likewise addresses the requirement ...
The Effects of Organ-based Tube Current Modulation on Radiation
... The purpose of this thesis was to quantify dose and noise performance of organ-dosebased tube current modulation (ODM) through experimental studies with an anthropomorphic phantom and simulations with a voxelized phantom library. Tube current modulation is a dose reduction technique that modulates r ...
... The purpose of this thesis was to quantify dose and noise performance of organ-dosebased tube current modulation (ODM) through experimental studies with an anthropomorphic phantom and simulations with a voxelized phantom library. Tube current modulation is a dose reduction technique that modulates r ...
A Monte Carlo dose simulation of chest and hip joint tomosynthesis
... possible to produce tomosynthesis images at about the same time as a conventional chest exam. This could possibly give a reduction in the amount of CT scans, which could result in lowering both cost and radiation dose (4). The effective dose from a chest tomosynthesis examination in a study at the U ...
... possible to produce tomosynthesis images at about the same time as a conventional chest exam. This could possibly give a reduction in the amount of CT scans, which could result in lowering both cost and radiation dose (4). The effective dose from a chest tomosynthesis examination in a study at the U ...
A Monte Carlo based three-dimensional dose reconstruction
... Our 3-D pretreatment dose verification should allow an independent verification of IMRT delivery by using measured portal images in combination with an independent dose calculation algorithm based on a Monte Carlo dose engine. Such a model would replace the need for performing film or ionization cha ...
... Our 3-D pretreatment dose verification should allow an independent verification of IMRT delivery by using measured portal images in combination with an independent dose calculation algorithm based on a Monte Carlo dose engine. Such a model would replace the need for performing film or ionization cha ...
Instruments for Radiation Detection and Measurement
... radiopharmaceutical results in poor-quality images due to the high background from the surrounding tissues and the blood, and gives unnecessary radiation dose to the patient ...
... radiopharmaceutical results in poor-quality images due to the high background from the surrounding tissues and the blood, and gives unnecessary radiation dose to the patient ...
Dose and image quality for a cone-beam C-arm
... various dose levels and tube voltages and an associated measurement method. Unlike conventional CT, the beam length covers the entire phantom, hence, the concept of computed tomography dose index 共CTDI兲 is not the metric of choice, and one can revert to conventional dosimetry methods by directly mea ...
... various dose levels and tube voltages and an associated measurement method. Unlike conventional CT, the beam length covers the entire phantom, hence, the concept of computed tomography dose index 共CTDI兲 is not the metric of choice, and one can revert to conventional dosimetry methods by directly mea ...
Contents
... In this thesis the focus will be on another area of use for the EPID, namely that of dosimetric verification of treatment fields. The idea is to calibrate the detector to give pixel values proportional to dose, so that a portal dose image (PDI) is obtained. To calibrate the EPID for dosimetry requir ...
... In this thesis the focus will be on another area of use for the EPID, namely that of dosimetric verification of treatment fields. The idea is to calibrate the detector to give pixel values proportional to dose, so that a portal dose image (PDI) is obtained. To calibrate the EPID for dosimetry requir ...
An Introduction to Fluoroscopy Safety
... No observable effects should occur in most patients. 2-5 Gy Range Doses in this range may result in mild transient erythema appearing within 24 hours and fading by 48 hours. There may also be temporary epilation from exposed skin beginning in about 3 weeks with regrowth in 8 to 12 weeks. Recommended ...
... No observable effects should occur in most patients. 2-5 Gy Range Doses in this range may result in mild transient erythema appearing within 24 hours and fading by 48 hours. There may also be temporary epilation from exposed skin beginning in about 3 weeks with regrowth in 8 to 12 weeks. Recommended ...
Understanding Radiation Units - Radiation Protection of Patients
... • Effective dose takes into account the organ specific radio-sensitivity to develop cancer and hereditary effects from radiation ...
... • Effective dose takes into account the organ specific radio-sensitivity to develop cancer and hereditary effects from radiation ...
SOMATOM Definition AS
... Every CT examination poses individual and specific requirements to achieve the optimum clinical outcome. These vary from institution to institution, from user to user, from patient to patient, The challenge is to find and apply the ideal settings for every individual examination, but at the same tim ...
... Every CT examination poses individual and specific requirements to achieve the optimum clinical outcome. These vary from institution to institution, from user to user, from patient to patient, The challenge is to find and apply the ideal settings for every individual examination, but at the same tim ...
IMRT verification by three-dimensional dose reconstruction
... amorphous silicon flat-panel13,14 systems. Pretreatment verification of 2-D intensity-modulated beam portals has also been demonstrated for both camera-based15,16 and liquid ionization chamber-based systems.17,18 In vivo dosimetric measurements were demonstrated using a camera-based EPID by Kirby et ...
... amorphous silicon flat-panel13,14 systems. Pretreatment verification of 2-D intensity-modulated beam portals has also been demonstrated for both camera-based15,16 and liquid ionization chamber-based systems.17,18 In vivo dosimetric measurements were demonstrated using a camera-based EPID by Kirby et ...
Diagnostic Reference Levels in Medical Imaging
... In setting diagnostic reference levels, regional, national and local authorized bodies and professional groups should be cognizant of these considerations. Additional Advice on Diagnostic Reference Levels from ICRP Committee 3 Objective of a Diagnostic Reference Level (12) The objective of a diagnos ...
... In setting diagnostic reference levels, regional, national and local authorized bodies and professional groups should be cognizant of these considerations. Additional Advice on Diagnostic Reference Levels from ICRP Committee 3 Objective of a Diagnostic Reference Level (12) The objective of a diagnos ...
Study on the Computed Tomography Dose Index volume
... System); consists of 16 detector cells in the Z direction. Each of the detector cells are 1.25 mm and the detector configurations available were 4 x 1.25 mm, 4 x 2.5 mm, 4 x 3.75 mm, 4 x 5.0 mm, 1 x 1.25 mm, and 2 x 0.63 mm. All dose measurement used a pencil beam ion chamber (VICTOREEN CT Probes, M ...
... System); consists of 16 detector cells in the Z direction. Each of the detector cells are 1.25 mm and the detector configurations available were 4 x 1.25 mm, 4 x 2.5 mm, 4 x 3.75 mm, 4 x 5.0 mm, 1 x 1.25 mm, and 2 x 0.63 mm. All dose measurement used a pencil beam ion chamber (VICTOREEN CT Probes, M ...
9 Three-Dimensional Treatment Planning and Conformal Therapy
... The CT scan must be performed with the patient in the treatment position, as determined in the preplanning step. The CT topograms should be generated first and reviewed prior to acquiring the planning scan to insure that patient alignment is correct; adjustments are made if needed. Radiopaque marker ...
... The CT scan must be performed with the patient in the treatment position, as determined in the preplanning step. The CT topograms should be generated first and reviewed prior to acquiring the planning scan to insure that patient alignment is correct; adjustments are made if needed. Radiopaque marker ...
AP Revision Guide Ch 18
... Every atom contains a nucleus which is composed of protons and neutrons. Because neutrons and protons are similar in many respects they are collectively termed nucleons. The nucleon number (also called the mass number) A of an isotope is the number of protons and neutrons in each nucleus of the isot ...
... Every atom contains a nucleus which is composed of protons and neutrons. Because neutrons and protons are similar in many respects they are collectively termed nucleons. The nucleon number (also called the mass number) A of an isotope is the number of protons and neutrons in each nucleus of the isot ...
Radiation Dose and Safety: Informatics Standards and Tools
... of absorbed dose is the gray (Gy), equal to 1 joule of energy deposited in 1 kilogram of medium. A common measurement is air kerma (kinetic energy released in a small volume of air), made using an ionization chamber and electrometer to measure the incident energy, usually in mGy units. Other dose va ...
... of absorbed dose is the gray (Gy), equal to 1 joule of energy deposited in 1 kilogram of medium. A common measurement is air kerma (kinetic energy released in a small volume of air), made using an ionization chamber and electrometer to measure the incident energy, usually in mGy units. Other dose va ...
Does the use of additional X-ray beam filtration during cine
... to reduce staff dose [23]. Modern X-ray systems can be programmed to employ Xray beam filters in acquisition as well as in fluoroscopy, and this has become common practice, reducing patient dose in cardiac interventions [15, 27] and neurological interventions [25]. However, the literature demonstrat ...
... to reduce staff dose [23]. Modern X-ray systems can be programmed to employ Xray beam filters in acquisition as well as in fluoroscopy, and this has become common practice, reducing patient dose in cardiac interventions [15, 27] and neurological interventions [25]. However, the literature demonstrat ...