Cone Beam Computed Tomography
... positioning, volume size (FOV), radiation quality, image capturing and reconstruction, image resolution and radiation dose. When new technology is introduced one must make sure that diagnostic accuracy is better or at least as good as the one it can be expected to replace. The CBCT brand tested was ...
... positioning, volume size (FOV), radiation quality, image capturing and reconstruction, image resolution and radiation dose. When new technology is introduced one must make sure that diagnostic accuracy is better or at least as good as the one it can be expected to replace. The CBCT brand tested was ...
Full Text - Journal of The Royal Society Interface
... although this is increasingly being addressed by multidetector scanners and by techniques that allow respiratory gating. Regional expansion has been measured by registration-based techniques [13– 16]. However, owing to the lack of dynamic imaging capacity, previous studies have resorted to inferring ...
... although this is increasingly being addressed by multidetector scanners and by techniques that allow respiratory gating. Regional expansion has been measured by registration-based techniques [13– 16]. However, owing to the lack of dynamic imaging capacity, previous studies have resorted to inferring ...
Advanced Imaging of Arthritis - Society for Pediatric Radiology
... -High spatial resolution -CT development with multirow detector systems: improved temporal resolution – potential for measurement of physiologic perfusion rather than only morphologic assessment Disadvantages: -Limited soft-tissue contrast sensitivity -Deleterious x-ray energy absorption ...
... -High spatial resolution -CT development with multirow detector systems: improved temporal resolution – potential for measurement of physiologic perfusion rather than only morphologic assessment Disadvantages: -Limited soft-tissue contrast sensitivity -Deleterious x-ray energy absorption ...
Evaluation and Validation of Computed Tomography Dose Accuracy
... from the two techniques. Tube currents of 140 mAs, 240 mAs and 300 mAs yielded 3.5%, 0.61% and -6.45% deviations when the respective CTDIvol values for both techniques were compared. There were mean CTDIvol of (42.3 + 8.6) mGy and (42.1 + 8.1) mGy for Barracuda and Ion Chamber techniques respectivel ...
... from the two techniques. Tube currents of 140 mAs, 240 mAs and 300 mAs yielded 3.5%, 0.61% and -6.45% deviations when the respective CTDIvol values for both techniques were compared. There were mean CTDIvol of (42.3 + 8.6) mGy and (42.1 + 8.1) mGy for Barracuda and Ion Chamber techniques respectivel ...
Effective dose range for dental cone beam computed tomography
... increased substantially and new models are being developed and released on a continuous basis. These devices exhibit a wide variability in terms of crucial exposure parameters such as the X-ray spectrum (voltage peak and filtration), X-ray exposure (mA and number of projections) and volume of the exp ...
... increased substantially and new models are being developed and released on a continuous basis. These devices exhibit a wide variability in terms of crucial exposure parameters such as the X-ray spectrum (voltage peak and filtration), X-ray exposure (mA and number of projections) and volume of the exp ...
3 JCI dosimetry for CT
... The [critical access] hospital reviews and analyzes incidents where the radiation dose index (CTDIvol, DLP, or size-specific dose estimate [SSDE]) from diagnostic CT examinations exceeded expected dose index ranges identified in imaging protocols. These incidents are then compared to external be ...
... The [critical access] hospital reviews and analyzes incidents where the radiation dose index (CTDIvol, DLP, or size-specific dose estimate [SSDE]) from diagnostic CT examinations exceeded expected dose index ranges identified in imaging protocols. These incidents are then compared to external be ...
Small Animal radiography Stifle Joint and CruS
... accurate assessment of the osseous and soft tissue structures of the stifle joint. This becomes even more critical when corrective osteotomies that alter joint alignment (tibial plateau leveling osteotomy or tibial tuberosity advancement) are performed. The standard of care in small animal veterinar ...
... accurate assessment of the osseous and soft tissue structures of the stifle joint. This becomes even more critical when corrective osteotomies that alter joint alignment (tibial plateau leveling osteotomy or tibial tuberosity advancement) are performed. The standard of care in small animal veterinar ...
PPCO Twist System - Today`s Veterinary Practice journal of
... accurate assessment of the osseous and soft tissue structures of the stifle joint. This becomes even more critical when corrective osteotomies that alter joint alignment (tibial plateau leveling osteotomy or tibial tuberosity advancement) are performed. The standard of care in small animal veterinar ...
... accurate assessment of the osseous and soft tissue structures of the stifle joint. This becomes even more critical when corrective osteotomies that alter joint alignment (tibial plateau leveling osteotomy or tibial tuberosity advancement) are performed. The standard of care in small animal veterinar ...
Chapter 1 Introduction to NDE
... retirement-for-cause NDE methods. Instead of being retired after a predetermined lifetime, a part or structure (such as an aircraft) is now often retired only if found to be defective. For example, a significant portion of the U.S. commercial and military air fleet has remained in operation well ...
... retirement-for-cause NDE methods. Instead of being retired after a predetermined lifetime, a part or structure (such as an aircraft) is now often retired only if found to be defective. For example, a significant portion of the U.S. commercial and military air fleet has remained in operation well ...
Understanding Radiation Units - Radiation Protection of Patients
... should become familiar with the following: • Why is it important to measure radiation dose in children? • How radiation dose can and should be expressed? • Understand the radiation quantities and units used in diagnostic radiology. ...
... should become familiar with the following: • Why is it important to measure radiation dose in children? • How radiation dose can and should be expressed? • Understand the radiation quantities and units used in diagnostic radiology. ...
Self-Referral CT Screening Application Guide (PDF: 420KB/34pages)
... To apply for an approval of CT self-referral screening, complete the “Application for CT screening.” Complete Items 1 through 4 on the form itself. For Items 5 through 18, submit the information on supplementary pages. Identify each sheet or document with the item number on the application. All type ...
... To apply for an approval of CT self-referral screening, complete the “Application for CT screening.” Complete Items 1 through 4 on the form itself. For Items 5 through 18, submit the information on supplementary pages. Identify each sheet or document with the item number on the application. All type ...
CCR Template - Colorado Secretary of State
... electrons accelerated from the cathode and from which the useful beam originates. ...
... electrons accelerated from the cathode and from which the useful beam originates. ...
Estimativa de dose nos pulmões para procedimentos
... detector cross talk, however the geometric efficiency is also reduced. CT detectors are much more expensive than those used in conventional radiography. (souce: Bushberg; Seibert; Leidholdt Jr; Boone, 2011). ............................................................................................ ...
... detector cross talk, however the geometric efficiency is also reduced. CT detectors are much more expensive than those used in conventional radiography. (souce: Bushberg; Seibert; Leidholdt Jr; Boone, 2011). ............................................................................................ ...
radiation protection in diagnostic radiology
... collimation. Otherwise the patient would be over-irradiated, by receiving radiation over a larger volume. Irradiating a smaller volume also minimizes the amount of scattered radiation and improves image contrast. • When using equipment without automatic X Ray beam collimation, it should be verified ...
... collimation. Otherwise the patient would be over-irradiated, by receiving radiation over a larger volume. Irradiating a smaller volume also minimizes the amount of scattered radiation and improves image contrast. • When using equipment without automatic X Ray beam collimation, it should be verified ...
Cone-beam computed tomography with a flat
... An imaging system for guidance has several requirements if it is to be applied in radiotherapy of the prostate. These include: 共i兲 contrast sensitivity sufficient to discern softtissue; 共ii兲 high spatial resolution and low geometric distortion for precise localization of soft-tissue boundaries; 共iii ...
... An imaging system for guidance has several requirements if it is to be applied in radiotherapy of the prostate. These include: 共i兲 contrast sensitivity sufficient to discern softtissue; 共ii兲 high spatial resolution and low geometric distortion for precise localization of soft-tissue boundaries; 共iii ...
AnnuAL REpoRt - European XFEL
... in the vast underground tunnels, the accelerator modules are being installed at a swift pace along with undulators and other photon systems, while hutches in the experiment hall are being readied for the installation of the scientific instruments. The contours of what will become the world’s best fa ...
... in the vast underground tunnels, the accelerator modules are being installed at a swift pace along with undulators and other photon systems, while hutches in the experiment hall are being readied for the installation of the scientific instruments. The contours of what will become the world’s best fa ...
ABDOMINAL EXAMINATION IN KNH USING 16 MULTI-SLICE
... indications were. The CT diagnostic findings were also analyzed in view of how they offered clinical solutions to the requesting clinician. Association between the specificity of the indication and the CT result was also studied. Dose quantification was done through estimation of effective dose, E c ...
... indications were. The CT diagnostic findings were also analyzed in view of how they offered clinical solutions to the requesting clinician. Association between the specificity of the indication and the CT result was also studied. Dose quantification was done through estimation of effective dose, E c ...
6 CCR 1007-1 Part 02 RADIATION CONTROL
... “Examination” means performing a procedure, including selection of exposure settings, positioning the x-ray system and the patient, and initiating and terminating the exposure. “Facility” means, for purposes of Part 2, the location within one building (or vehicle, or under one roof, or at one addres ...
... “Examination” means performing a procedure, including selection of exposure settings, positioning the x-ray system and the patient, and initiating and terminating the exposure. “Facility” means, for purposes of Part 2, the location within one building (or vehicle, or under one roof, or at one addres ...
Nuclear Physics in Medicine
... «A century ago, the living body, like most of the material world, was opaque. Then Wilhelm Roentgen captured an X-ray image of his wife’s finger – her wedding ring “floating” around a white bone – and our range of vision changed for ever». From the words of Bettyann Holtzmann Kelves up to now, amazi ...
... «A century ago, the living body, like most of the material world, was opaque. Then Wilhelm Roentgen captured an X-ray image of his wife’s finger – her wedding ring “floating” around a white bone – and our range of vision changed for ever». From the words of Bettyann Holtzmann Kelves up to now, amazi ...
Nigerian Radiation Safety in Diagnostic and Interventional
... except, for the purposes of Nigeria Basic Ionizing Radiation Regulations, when subject to occupational or medical exposure. For the purpose of verifying compliance with the annual dose limit for public exposure, the representative individual in the relevant critical group; "normal exposure" means an ...
... except, for the purposes of Nigeria Basic Ionizing Radiation Regulations, when subject to occupational or medical exposure. For the purpose of verifying compliance with the annual dose limit for public exposure, the representative individual in the relevant critical group; "normal exposure" means an ...
Innova X-ray Dose Efficiency: Objective Evidence
... distance are those commonly used by clinicians in performing interventional procedures on a given system. Methods and Controls: Studies must be scientific, evidence-based, and preferably peer-reviewed. Given all the sources of variability in interventional procedures, adequate controls for a number ...
... distance are those commonly used by clinicians in performing interventional procedures on a given system. Methods and Controls: Studies must be scientific, evidence-based, and preferably peer-reviewed. Given all the sources of variability in interventional procedures, adequate controls for a number ...
ICRP PUBLICATION 121: Radiological Protection in Paediatric
... is particularly important for high-dose examinations, such as complex diagnostic and interventional procedures. In this case, ‘Individual justification by the practitioner is particularly important and should take account of all the available information. This includes the details of the proposed pro ...
... is particularly important for high-dose examinations, such as complex diagnostic and interventional procedures. In this case, ‘Individual justification by the practitioner is particularly important and should take account of all the available information. This includes the details of the proposed pro ...
Intervention Research, Council on Clinical Cardiology, and Council
... Computed Tomography, and the North American Society for Cardiovascular Imaging should support this effort or develop similar initiatives. For those physicians who will be performing cardiac imaging, more extensive training (compared with referring physicians) should be required. The expectations for ...
... Computed Tomography, and the North American Society for Cardiovascular Imaging should support this effort or develop similar initiatives. For those physicians who will be performing cardiac imaging, more extensive training (compared with referring physicians) should be required. The expectations for ...
AAPM Imaging Physics Curricula Subcommittee
... Q8. A person accidentally ingests an unknown radioactive substance and lives in close proximity with his or her family. Which of the following types of radiation is the greatest safety concern for the family? A. Photons (364 keV) B. Neutrinos C. Electrons (30 keV) D. Alpha particles Answer: A – Phot ...
... Q8. A person accidentally ingests an unknown radioactive substance and lives in close proximity with his or her family. Which of the following types of radiation is the greatest safety concern for the family? A. Photons (364 keV) B. Neutrinos C. Electrons (30 keV) D. Alpha particles Answer: A – Phot ...
X-ray
X-radiation (composed of X-rays) is a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3×1016 Hz to 3×1019 Hz) and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to with terms meaning Röntgen radiation, after Wilhelm Röntgen, who is usually credited as its discoverer, and who had named it X-radiation to signify an unknown type of radiation. Spelling of X-ray(s) in the English language includes the variants x-ray(s), xray(s) and X ray(s).X-rays with photon energies above 5–10 keV (below 0.2–0.1 nm wavelength) are called hard X-rays, while those with lower energy are called soft X-rays. Due to their penetrating ability, hard X-rays are widely used to image the inside of objects, e.g., in medical radiography and airport security. As a result, the term X-ray is metonymically used to refer to a radiographic image produced using this method, in addition to the method itself. Since the wavelengths of hard X-rays are similar to the size of atoms they are also useful for determining crystal structures by X-ray crystallography. By contrast, soft X-rays are easily absorbed in air and the attenuation length of 600 eV (~2 nm) X-rays in water is less than 1 micrometer.There is no universal consensus for a definition distinguishing between X-rays and gamma rays. One common practice is to distinguish between the two types of radiation based on their source: X-rays are emitted by electrons, while gamma rays are emitted by the atomic nucleus. This definition has several problems; other processes also can generate these high energy photons, or sometimes the method of generation is not known. One common alternative is to distinguish X- and gamma radiation on the basis of wavelength (or equivalently, frequency or photon energy), with radiation shorter than some arbitrary wavelength, such as 10−11 m (0.1 Å), defined as gamma radiation.This criterion assigns a photon to an unambiguous category, but is only possible if wavelength is known. (Some measurement techniques do not distinguish between detected wavelengths.) However, these two definitions often coincide since the electromagnetic radiation emitted by X-ray tubes generally has a longer wavelength and lower photon energy than the radiation emitted by radioactive nuclei.Occasionally, one term or the other is used in specific contexts due to historical precedent, based on measurement (detection) technique, or based on their intended use rather than their wavelength or source.Thus, gamma-rays generated for medical and industrial uses, for example radiotherapy, in the ranges of 6–20 MeV, can in this context also be referred to as X-rays.