RESEARCH ARTICLE New Directions in X
... that could be resolved with these instruments to around a micrometer, or slightly less. A huge amount of information was accumulated using these microscopes especially about biology and medicine. The microscopist is very often faced with the need to improve the resolution, to see more detail in the ...
... that could be resolved with these instruments to around a micrometer, or slightly less. A huge amount of information was accumulated using these microscopes especially about biology and medicine. The microscopist is very often faced with the need to improve the resolution, to see more detail in the ...
Radiation Protection and Dose Monitoring in Medical
... practical, consensus-based dose-recording quality measures becomes even more important. Also, any measure should be accompanied by clear guidelines for implementation by the facility and third-party auditors (e.g., by regulators or accreditation organizations). While recent measures (16) may be corr ...
... practical, consensus-based dose-recording quality measures becomes even more important. Also, any measure should be accompanied by clear guidelines for implementation by the facility and third-party auditors (e.g., by regulators or accreditation organizations). While recent measures (16) may be corr ...
Digital Medical Linear Accelerator Specifications. Fighting cancer
... preset value. Backup termination is provided by the secondary dose monitor and time interlock systems. In case of power failure during treatment, MUs, arc, and time values, as well as all other treatment setup parameters, are stored in nonvolatile memory for ...
... preset value. Backup termination is provided by the secondary dose monitor and time interlock systems. In case of power failure during treatment, MUs, arc, and time values, as well as all other treatment setup parameters, are stored in nonvolatile memory for ...
Radiation Hygiene Requirements for IGRT (Image Guided
... megavolt (MV) treatment beam (field control images, verification images), although films have recently been replaced with electronic portal imaging devices (EPIDs). Today, low energy photon sources (kV) and an additional EPID mounted to the accelerator gantry are available. These devices can be used ...
... megavolt (MV) treatment beam (field control images, verification images), although films have recently been replaced with electronic portal imaging devices (EPIDs). Today, low energy photon sources (kV) and an additional EPID mounted to the accelerator gantry are available. These devices can be used ...
Quality Assurance (QA) for Kilovoltage Cone Beam
... imaging. The Penta Guide (Figure 3) offers limited image quality for MV imaging. However, the authors have used it successfully over several years. The ISO Cube phantom (Figure 4) offers better MV imaging, but has less favorable kV CBCT image quality. A phantom that offers very good kV CBCT and MV i ...
... imaging. The Penta Guide (Figure 3) offers limited image quality for MV imaging. However, the authors have used it successfully over several years. The ISO Cube phantom (Figure 4) offers better MV imaging, but has less favorable kV CBCT image quality. A phantom that offers very good kV CBCT and MV i ...
j20-1999-mia-revision-thr
... (v) interpolating the missing projection data and reconstructing the images from these completed projections (Oppenheim, 1977; Hinderling et al., 1979; Glover and Pelc, 1981; Kalender et al., 1987; Medoff, 1987; Klotz et al., 1990); and (vi) creating simulated projection data from the images, interp ...
... (v) interpolating the missing projection data and reconstructing the images from these completed projections (Oppenheim, 1977; Hinderling et al., 1979; Glover and Pelc, 1981; Kalender et al., 1987; Medoff, 1987; Klotz et al., 1990); and (vi) creating simulated projection data from the images, interp ...
GE Healthcare Discovery* CT750 HD Great care by design
... Using known attenuation curves, the material specific difference in attenuation enables an easy classification of the elementary chemical composition of the scanned tissue. This creates the ability to generate material density images. Spectral images are derived from the material density images and ...
... Using known attenuation curves, the material specific difference in attenuation enables an easy classification of the elementary chemical composition of the scanned tissue. This creates the ability to generate material density images. Spectral images are derived from the material density images and ...
Weightbearing CBCT, MDCT, and 2D imaging dosimetry of the foot
... measuring approximately 1 mm ×10 mm× 10 mm. This case prevents loss of energy through stimulation by ambient light. Dosimeters used in this study were read with a portable reader (MicroStar, Landauer, Inc., Glenwood, IL). The reader was calibrated before use. Following calibration, photon counts fro ...
... measuring approximately 1 mm ×10 mm× 10 mm. This case prevents loss of energy through stimulation by ambient light. Dosimeters used in this study were read with a portable reader (MicroStar, Landauer, Inc., Glenwood, IL). The reader was calibrated before use. Following calibration, photon counts fro ...
Walter et al. (2007) Radiotherapy and Oncology 85
... A more detailed view of the bony structure and soft tissue can be achieved by using photons of lower energy, for example with an X-ray source inside the treatment room emitting photons with a maximum energy of 80–140 keV. While these devices provide images of the bony anatomy with better quality tha ...
... A more detailed view of the bony structure and soft tissue can be achieved by using photons of lower energy, for example with an X-ray source inside the treatment room emitting photons with a maximum energy of 80–140 keV. While these devices provide images of the bony anatomy with better quality tha ...
Winnovative HTML to PDF Converter for .NET
... procedure have changed and progressed. Technology advancements have affected almost all parts of the mammography units, with the highest impact on films and intensifying screens.2,3 Screen-film systems are currently dominating the market and offer excellent detection capabilities of early or occult ...
... procedure have changed and progressed. Technology advancements have affected almost all parts of the mammography units, with the highest impact on films and intensifying screens.2,3 Screen-film systems are currently dominating the market and offer excellent detection capabilities of early or occult ...
Radiologists` Preferences for Digital Mammographic
... judgment. Again, craniocaudal images were rated first, followed by mediolateral oblique images. The radiologists completed the tasks in the order in which they were presented. To limit the effects of fatigue, short breaks (at least 5 minutes) were required after every 50 minutes of work. The radiolo ...
... judgment. Again, craniocaudal images were rated first, followed by mediolateral oblique images. The radiologists completed the tasks in the order in which they were presented. To limit the effects of fatigue, short breaks (at least 5 minutes) were required after every 50 minutes of work. The radiolo ...
x-ray examinations in health care
... examinee to radiation. Radiation exposure shall be kept as low as is reasonably achievable also during examinations that are not medical in nature. The optimization requires the following, among other matters: • the staff participating in the use of radiation meet the qualification requirements, an ...
... examinee to radiation. Radiation exposure shall be kept as low as is reasonably achievable also during examinations that are not medical in nature. The optimization requires the following, among other matters: • the staff participating in the use of radiation meet the qualification requirements, an ...
Image-guIded Surgery
... Image guidance for surgical interventions is a tool, and it too is only as good as its human operator. Proper use of an image-guidance system is vital to both safety and efficacy in the operating room, and because these systems are becoming so widespread and at the same time are becoming so sophisti ...
... Image guidance for surgical interventions is a tool, and it too is only as good as its human operator. Proper use of an image-guidance system is vital to both safety and efficacy in the operating room, and because these systems are becoming so widespread and at the same time are becoming so sophisti ...
Digital radiography with large-area flat
... 43×35 cm. Larger views (i.e. full spine or full leg) can be created by electronically pasting more than one single image [12, 13]. If the detector is to be retrofitted in existing radiography installations, i.e. Bucky tables, its thickness is limited by the mechanical constraints of the table. All F ...
... 43×35 cm. Larger views (i.e. full spine or full leg) can be created by electronically pasting more than one single image [12, 13]. If the detector is to be retrofitted in existing radiography installations, i.e. Bucky tables, its thickness is limited by the mechanical constraints of the table. All F ...
Full Text - RSNA Publications Online
... from radiation scattered within the patient. It is, however, a quantity that can be easily measured and compared among facilities. Kerma.—To characterize an x-ray field, the quantity exposure is being replaced by the quantity air kerma. Kerma (an acronym for kinetic energy released per unit mass) is ...
... from radiation scattered within the patient. It is, however, a quantity that can be easily measured and compared among facilities. Kerma.—To characterize an x-ray field, the quantity exposure is being replaced by the quantity air kerma. Kerma (an acronym for kinetic energy released per unit mass) is ...
VistA Imaging Brown Bag Discussion - Dicom
... images to line up the way providers want them? • Need to identify the sensor apart from the system that handles the images – Acquisition Context Sequence generally empty because there are no template definitions in the IODs ...
... images to line up the way providers want them? • Need to identify the sensor apart from the system that handles the images – Acquisition Context Sequence generally empty because there are no template definitions in the IODs ...
Quantitative Attenuation Correction for PET/CT Using
... of the significant noise amplification and the additional patient radiation dose required to perform second scan and to reduce noise. Figure 5 summarizes the steps involved in dual energy CT-Based attenuation correction. Our goal is to use dual energy CT for PET attenuation correction with a statist ...
... of the significant noise amplification and the additional patient radiation dose required to perform second scan and to reduce noise. Figure 5 summarizes the steps involved in dual energy CT-Based attenuation correction. Our goal is to use dual energy CT for PET attenuation correction with a statist ...
R E V I E W Physics,
... Computer-Aided Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Glossary . . . . . . . . . . . . . ...
... Computer-Aided Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Glossary . . . . . . . . . . . . . ...
Chapter 2 Scope of Coverage for Part I and Part II Resident Physicist
... 1 The examination shall be in the form of an oral examination and shall be conducted by a panel of 4 examiners, one of whom is usually an external examiner. The total examination time for each candidate shall be approximately 1 hour and 30 minutes. 2 The examination will mainly be based on, but not ...
... 1 The examination shall be in the form of an oral examination and shall be conducted by a panel of 4 examiners, one of whom is usually an external examiner. The total examination time for each candidate shall be approximately 1 hour and 30 minutes. 2 The examination will mainly be based on, but not ...
Contrast: Contrast:
... your hand or arm to give you the contrast agent. Then staff will take your hand or arm to give you the contrast agent. Then staff will take more pictures as the contrast enters your heart. The contrast agent does more pictures as the contrast enters your heart. The contrast agent does not not last l ...
... your hand or arm to give you the contrast agent. Then staff will take your hand or arm to give you the contrast agent. Then staff will take more pictures as the contrast enters your heart. The contrast agent does more pictures as the contrast enters your heart. The contrast agent does not not last l ...
images - University of Florida Health Science Center
... Interactive Reconstruction in Image Space (IRIS) is currently being tested on CT heads, chests and abdomens. IRIS I can save up to 60% dose for a wide range of routine applications while maintaining excellent image quality. At the Annex, they began with a 20% reduction in radiation dose. This allows ...
... Interactive Reconstruction in Image Space (IRIS) is currently being tested on CT heads, chests and abdomens. IRIS I can save up to 60% dose for a wide range of routine applications while maintaining excellent image quality. At the Annex, they began with a 20% reduction in radiation dose. This allows ...
Novel clinical applications of dual energy computed tomography
... of this technology is a non-rectangular voltage retention on the X-ray tube with limited adaptation of the current, which leads to a much lower signal at low energy than at high energy. ...
... of this technology is a non-rectangular voltage retention on the X-ray tube with limited adaptation of the current, which leads to a much lower signal at low energy than at high energy. ...
Cone Beam Computed Tomography in Endodontics: An Overview.
... system. In cases where in the periradicular healing is incomplete, this acts as a baseline for assessment of healing in the medium. Imaging is very important in evaluating the results of the previous therapy and delayed healing, evaluating potential obstacles to the retreatment, as well as aid surgi ...
... system. In cases where in the periradicular healing is incomplete, this acts as a baseline for assessment of healing in the medium. Imaging is very important in evaluating the results of the previous therapy and delayed healing, evaluating potential obstacles to the retreatment, as well as aid surgi ...
Fluoroscopy
Fluoroscopy /flɔrˈɒskəpi/ is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope /ˈflɔrɵˌskoʊp/ allows a physician to see the internal structure and function of a patient, so that the pumping action of the heart or the motion of swallowing, for example, can be watched. This is useful for both diagnosis and therapy and occurs in general radiology, interventional radiology, and image-guided surgery. In its simplest form, a fluoroscope consists of an X-ray source and a fluorescent screen, between which a patient is placed. However, since the 1950s most fluoroscopes have included X-ray image intensifiers and cameras as well, to improve the image's visibility and make it available on a remote display screen. For many decades fluoroscopy tended to produce live pictures that were not recorded, but since the 1960s, as technology improved, recording and playback became the norm.Fluoroscopy is similar to radiography and X-ray computed tomography (X-ray CT) in that it generates images using X-rays. The original difference was that radiography fixed still images on film whereas fluoroscopy provided live moving pictures that were not stored. However, today radiography, CT, and fluoroscopy are all digital imaging modes with image analysis software and data storage and retrieval. The use of X-rays, a form of ionizing radiation, requires the potential risks from a procedure to be carefully balanced with the benefits of the procedure to the patient. Because the patient must be exposed to a continuous source of x-rays instead of a momentary pulse, a fluoroscopy procedure generally subjects a patient to a higher absorbed dose of radiation than an ordinary (still) radiograph. Much research has been directed toward reducing radiation exposure, and recent advances in fluoroscopy technology such as digital image processing and flat panel detectors, have resulted in much lower radiation doses than former procedures.The type of fluoroscopy used in airport security (to check for hidden weapons or bombs) uses lower doses of radiation than medical fluoroscopy. It was formerly also used in retail stores in the form of shoe-fitting fluoroscopes, but such use was discontinued because it is no longer considered acceptable to use radiation exposure, however small the dose, for nonessential purposes. Only important applications such as health care, bodily safety, food safety, nondestructive testing, and scientific research meet the risk-benefit threshold for use. The reason for higher doses in medical applications is that they are more demanding about tissue contrast, and for the same reason they sometimes require contrast media.