Managing Patient Dose in Multi-Detector Computed Tomography
... of detectors (Elscint CT Twin) had already been on the market since 1992 and MDCT ...
... of detectors (Elscint CT Twin) had already been on the market since 1992 and MDCT ...
EVALUATION OF AN IN-LINE PHASE
... research. I would also like to thank Dr. Pickens and Dr. Donnelly who have both provided their insight and expertise in all things from theory to experiment to programming. I also like to thank my other committee members (Dr. Ernst, Dr. Peterson, and Dr. Stabin) for their feedback and dissertation a ...
... research. I would also like to thank Dr. Pickens and Dr. Donnelly who have both provided their insight and expertise in all things from theory to experiment to programming. I also like to thank my other committee members (Dr. Ernst, Dr. Peterson, and Dr. Stabin) for their feedback and dissertation a ...
Radiation risk from mammography - Hendrick
... are the focus of clinical investigation for U.S. Food and Drug Administration approval and also may be considered for screening in some women, such as ...
... are the focus of clinical investigation for U.S. Food and Drug Administration approval and also may be considered for screening in some women, such as ...
Essential Tips for Dental Radiographers
... Trick 2: Moving the Cone Due to a patient’s gag reflex, it is often impossible to position the sensor far enough posteriorly to get a clear shot of a maxillary second or third molar. It is also often difficult or nearly impossible to get a periapical of the entire first premolar due to the mandibula ...
... Trick 2: Moving the Cone Due to a patient’s gag reflex, it is often impossible to position the sensor far enough posteriorly to get a clear shot of a maxillary second or third molar. It is also often difficult or nearly impossible to get a periapical of the entire first premolar due to the mandibula ...
Techniques, Benefits, and Challenges of PET-MR
... nor its byproduct undergo normal catabolic or metabolic transformation, and it cannot be converted into a form that can exit the cell. This so-called “metabolic trapping” at the cellular level permits 18F-FDG to accumulate in abnormal cells.3,4 On the atomic level, the 18F begins to stabilize by rel ...
... nor its byproduct undergo normal catabolic or metabolic transformation, and it cannot be converted into a form that can exit the cell. This so-called “metabolic trapping” at the cellular level permits 18F-FDG to accumulate in abnormal cells.3,4 On the atomic level, the 18F begins to stabilize by rel ...
PM77 - Equipment used in connection with medical exposure
... of assembly from the factory, and any critical examination associated with them. While mobile equipment that is delivered fully assembled does not formally require a critical examination (if erected in the European Union, it should have been critically examined by the manufacturer), employers are ad ...
... of assembly from the factory, and any critical examination associated with them. While mobile equipment that is delivered fully assembled does not formally require a critical examination (if erected in the European Union, it should have been critically examined by the manufacturer), employers are ad ...
Initial experience with X-ray CT based attenuation correction in
... CAG. Reconstructed counts are artificially enhanced in the regions of high tissue density when scattered events are not removed from the projections prior to AC.13,17 This may be one of the main reasons why a decrease in activity appears in the LAD territory with AC. We postulate that over-correctio ...
... CAG. Reconstructed counts are artificially enhanced in the regions of high tissue density when scattered events are not removed from the projections prior to AC.13,17 This may be one of the main reasons why a decrease in activity appears in the LAD territory with AC. We postulate that over-correctio ...
C-arm Cone-beam CT - Society Of Interventional Radiology
... overcome the limitation of poor lowcontrast visibility, the angio-CT system was developed, which fuses a conventional angiographic system with a fanbeam CT scanner. The patient remains stationary, and a CT scanner on rails is rolled into position as needed. However, this system was expensive and req ...
... overcome the limitation of poor lowcontrast visibility, the angio-CT system was developed, which fuses a conventional angiographic system with a fanbeam CT scanner. The patient remains stationary, and a CT scanner on rails is rolled into position as needed. However, this system was expensive and req ...
X-ray spectral measurements for tungsten
... tube. We tackled this difficulty by reducing the tube current to 10–60 mA (depending on kVp) and setting the exposure time at the maximum value of 2.5 s, using a service software from Hologic. In addition, the two configurations of pinholes were carefully chosen to achieve a balance between the inci ...
... tube. We tackled this difficulty by reducing the tube current to 10–60 mA (depending on kVp) and setting the exposure time at the maximum value of 2.5 s, using a service software from Hologic. In addition, the two configurations of pinholes were carefully chosen to achieve a balance between the inci ...
Quality Assurance (QA) for Kilovoltage Cone Beam
... However, precise tests (~1 mm) of the agreement of kV CBCT and MV treatment isocenters are very comprehensive and time consuming. Therefore multiple levels of tests are generally used: faster and less precise ones for daily checks by Radiation Therapists and more precise tests for monthly checks and ...
... However, precise tests (~1 mm) of the agreement of kV CBCT and MV treatment isocenters are very comprehensive and time consuming. Therefore multiple levels of tests are generally used: faster and less precise ones for daily checks by Radiation Therapists and more precise tests for monthly checks and ...
Learn to identify and remedy artifacts in Computed Radiography
... for the film, which is replaced by an imaging plate that can be erased and reused for several years. Has technical advantadges over film radiography, as well as some extra possible pitfalls which must be properly watched for. ...
... for the film, which is replaced by an imaging plate that can be erased and reused for several years. Has technical advantadges over film radiography, as well as some extra possible pitfalls which must be properly watched for. ...
Lecture 15 QA programs Fri - gnssn
... complex procedures. • For some complex interventional procedures, maximum skin dose. • For CT scanner, CTDI and the number of slices (also Dose Length Product DLP). IAEA ...
... complex procedures. • For some complex interventional procedures, maximum skin dose. • For CT scanner, CTDI and the number of slices (also Dose Length Product DLP). IAEA ...
Diagnostic Reference Levels
... against the DRL value. Nuclear Medicine: In diagnostic nuclear medicine DRLs are expressed in terms of administered activities (MBq) rather than absorbed dose (2). The DRL values are not based on the 75th percentile but on the administered activity necessary for a good image on well- adjusted equipm ...
... against the DRL value. Nuclear Medicine: In diagnostic nuclear medicine DRLs are expressed in terms of administered activities (MBq) rather than absorbed dose (2). The DRL values are not based on the 75th percentile but on the administered activity necessary for a good image on well- adjusted equipm ...
Aquilion PRIME - Toshiba Medical Systems Europe
... Multi. We were delighted to see that due to the short reconstruction time after only two months of using the PRIME our performance had increased to 40 scans during a 9-to-5 working day. It is a pleasure for radiologists and technicians alike to work on the post-processing station to produce magnific ...
... Multi. We were delighted to see that due to the short reconstruction time after only two months of using the PRIME our performance had increased to 40 scans during a 9-to-5 working day. It is a pleasure for radiologists and technicians alike to work on the post-processing station to produce magnific ...
j20-1999-mia-revision-thr
... In addition to the direct patient benefits, these advantages can save costs, both by reducing operating room cost and by shortening the hospital stay and recovery time. In 1995, we initiated a joint effort to develop an integrated preoperative planning and intraoperative execution system for RTHR su ...
... In addition to the direct patient benefits, these advantages can save costs, both by reducing operating room cost and by shortening the hospital stay and recovery time. In 1995, we initiated a joint effort to develop an integrated preoperative planning and intraoperative execution system for RTHR su ...
Basic Imaging Principles
... modality. Thus, a given patient represents an ensemble of different objects or signals. In considering a given medical image, it is thus important to start with the physics that underlie the creation of signals from the patient for that modality. Accordingly, each part of this book is organized so t ...
... modality. Thus, a given patient represents an ensemble of different objects or signals. In considering a given medical image, it is thus important to start with the physics that underlie the creation of signals from the patient for that modality. Accordingly, each part of this book is organized so t ...
Compensators for dose and scatter management in cone
... also contributes additional x-ray quantum noise and induces localized artifacts such as streaking and reduced attenuation estimation at the center of the object 共known as a cupping artifact兲.6 Scattering within the patient also contributes additional dose to the patient, which does not necessarily c ...
... also contributes additional x-ray quantum noise and induces localized artifacts such as streaking and reduced attenuation estimation at the center of the object 共known as a cupping artifact兲.6 Scattering within the patient also contributes additional dose to the patient, which does not necessarily c ...
A Method to Measure the Detective Quantum Efficiency of
... optimal balance, it is critical that x-ray detectors be designed and maintained to produce the best possible image quality for a given radiation exposure. Unfortunately, not all x-ray systems provide patients with the benefits of optimal image quality for a given exposure, particularly for the visua ...
... optimal balance, it is critical that x-ray detectors be designed and maintained to produce the best possible image quality for a given radiation exposure. Unfortunately, not all x-ray systems provide patients with the benefits of optimal image quality for a given exposure, particularly for the visua ...
RADIATION PROTECTION IN DIAGNOSTIC RADIOLOGY
... • Receptor blur: (screen-film combination) can be as small as 0.1 - 0.15 mm (full width at half maximum of the point response function) with a limiting value as high as 20 cycles per mm • Geometric unsharpness: focal spot size and imaging geometry must be chosen so that the overall unsharpness refle ...
... • Receptor blur: (screen-film combination) can be as small as 0.1 - 0.15 mm (full width at half maximum of the point response function) with a limiting value as high as 20 cycles per mm • Geometric unsharpness: focal spot size and imaging geometry must be chosen so that the overall unsharpness refle ...
19. Optimization of protection in mammography - RPOP
... • Receptor blur: (screen-film combination) can be as small as 0.1 - 0.15 mm (full width at half maximum of the point response function) with a limiting value as high as 20 cycles per mm • Geometric unsharpness: focal spot size and imaging geometry must be chosen so that the overall unsharpness refle ...
... • Receptor blur: (screen-film combination) can be as small as 0.1 - 0.15 mm (full width at half maximum of the point response function) with a limiting value as high as 20 cycles per mm • Geometric unsharpness: focal spot size and imaging geometry must be chosen so that the overall unsharpness refle ...
Moving Beam Helical CT Scanning
... We implemented MBHS on a modified 9800 Hilight Scanner (GE Medical Systems, Milwaukee, WI). The collimator that we used is diagramed in Fig. 4. The key element of the collimator is a rotatable mandrel with a V-shaped slot. Instead of translating a collimator as described above, the mandrel is rotate ...
... We implemented MBHS on a modified 9800 Hilight Scanner (GE Medical Systems, Milwaukee, WI). The collimator that we used is diagramed in Fig. 4. The key element of the collimator is a rotatable mandrel with a V-shaped slot. Instead of translating a collimator as described above, the mandrel is rotate ...
Introduction of Radiographic Technology
... Viewing from the same perspective as the x-ray tube Marked R/L by the side of the patient closet to the IR Viewing from the same perspective as the x-ray tube Crosswise and p’t upside on view box upside ...
... Viewing from the same perspective as the x-ray tube Marked R/L by the side of the patient closet to the IR Viewing from the same perspective as the x-ray tube Crosswise and p’t upside on view box upside ...
The Reference in Single Source CT
... measurements. But this benefit is contradicted when compromises like reduced image detail or limited FoV have to be made in order to utilize high rotation speeds. Therefore, the SOMATOM Definition Edge was specifically designed to go beyond these limitations. Its revolutionary Stellar Detector provi ...
... measurements. But this benefit is contradicted when compromises like reduced image detail or limited FoV have to be made in order to utilize high rotation speeds. Therefore, the SOMATOM Definition Edge was specifically designed to go beyond these limitations. Its revolutionary Stellar Detector provi ...
guidelines for the use of radiographs in clinicalorthodontics
... images were created. Within months medical diagnostic imaging had been revolutionised. These early images required high doses of radiation and very soon local side-effects such as skin reddening, hair loss and ulceration became apparent. Within only a few years it was realised that these diagnostica ...
... images were created. Within months medical diagnostic imaging had been revolutionised. These early images required high doses of radiation and very soon local side-effects such as skin reddening, hair loss and ulceration became apparent. Within only a few years it was realised that these diagnostica ...
Backscatter X-ray
Backscatter X-ray is an advanced X-ray imaging technology. Traditional X-ray machines detect hard and soft materials by the variation in transmission through the target. In contrast, backscatter X-ray detects the radiation that reflects from the target. It has potential applications where less-destructive examination is required, and can be used if only one side of the target is available for examination.The technology is one of two types of whole body imaging technologies that have been used to perform full-body scans of airline passengers to detect hidden weapons, tools, liquids, narcotics, currency, and other contraband. A competing technology is millimeter wave scanner. An airport security machine of this type is also referred to as ""body scanner"", ""whole body imager (WBI)"", ""security scanner"", and ""naked scanner"".