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Radiographs
Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical ("diagnostic" radiography and "therapeutic radiography") and industrial radiography. Similar techniques are used in airport security, (where "body scanners" generally use backscatter X-ray). To create an image in conventional radiography, a beam of X-rays is produced by an X-ray generator and it is projected towards the object. A certain amount of the X-rays or other radiation are absorbed by the object, dependent on the object's density and structural composition. The X-rays that pass through the object are captured behind the object by a detector (either photographic film or a digital detector). The generation of flat two-dimensional images by this technique is called projectional radiography. In computed tomography (CT scanning), an X-ray source and its associated de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Computed Tomography
An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ranging from 10 nanometers to 10 picometers, corresponding to frequencies in the range of 30 petahertz to 30 exahertz ( to ) and photon energies in the range of 100 eV to 100 keV, respectively. X-rays were discovered in 1895 by the German scientist Wilhelm Conrad Röntgen, who named it ''X-radiation'' to signify an unknown type of radiation.Novelline, Robert (1997). ''Squire's Fundamentals of Radiology''. Harvard University Press. 5th edition. . X-rays can penetrate many solid substances such as construction materials and living tissue, so X-ray radiography is widely used in medical diagnostics (e.g., checking for broken bones) and materials science (e.g., identification of some chemical elements and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Industrial Radiography
Industrial radiography is a modality of non-destructive testing that uses ionizing radiation to inspect materials and components with the objective of locating and quantifying defects and degradation in material properties that would lead to the failure of engineering structures. It plays an important role in the science and technology needed to ensure product quality and reliability. In Australia, industrial radiographic non-destructive testing is colloquially referred to as "bombing" a component with a "bomb". Industrial Radiography uses either X-rays, produced with X-ray generators, or gamma rays generated by the natural radioactivity of sealed radionuclide sources. Neutrons can also be used. After crossing the specimen, photons are captured by a X-ray detector, detector, such as a silver halide film, a Photostimulated luminescence, phosphor plate, flat panel detector or CdTe detector. The examination can be performed in static 2D (named radiography), in real time 2D (fluorosc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Projectional Radiography
Projectional radiography, also known as conventional radiography, is a form of radiography and medical imaging that produces two-dimensional images by X-ray radiation. The image acquisition is generally performed by radiographers, and the images are often examined by radiologists. Both the procedure and any resultant images are often simply called 'X-ray'. Plain radiography or roentgenography generally refers to projectional radiography (without the use of more advanced techniques such as CT scan, computed tomography that can generate 3D-images). ''Plain radiography'' can also refer to radiography without a radiocontrast agent or radiography that generates single static images, as contrasted to fluoroscopy, which are technically also projectional. Equipment X-ray generator Projectional radiographs generally use X-rays created by X-ray generators, which generate X-rays from X-ray tubes. Grid An anti-scatter grid may be placed between the patient and the detector to reduce the q ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conventional Radiography
Projectional radiography, also known as conventional radiography, is a form of radiography and medical imaging that produces two-dimensional images by X-ray radiation. The image acquisition is generally performed by radiographers, and the images are often examined by radiologists. Both the procedure and any resultant images are often simply called 'X-ray'. Plain radiography or roentgenography generally refers to projectional radiography (without the use of more advanced techniques such as computed tomography that can generate 3D-images). ''Plain radiography'' can also refer to radiography without a radiocontrast agent or radiography that generates single static images, as contrasted to fluoroscopy, which are technically also projectional. Equipment X-ray generator Projectional radiographs generally use X-rays created by X-ray generators, which generate X-rays from X-ray tubes. Grid An anti-scatter grid may be placed between the patient and the detector to reduce the quantit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiographer
Radiographers, also known as radiology technologists, radiologic technologists, diagnostic radiographers and medical radiation technologists, are healthcare professionals who specialise in the imaging of human anatomy for the diagnosis and treatment of pathology. Radiographers are sometimes popularly known as x-ray technologists, though this is misleading because while x-rays were the earliest form of medical imaging, the field also includes magnetic resonance imaging and other technologies that do not use x-rays. In countries that use the title ''radiologic technologist'', these professionals are often informally referred to as ''techs'' in the clinical environment; this phrase has emerged in popular culture such as television programmes. The term ''radiographer'' can also refer to a ''therapeutic radiographer'', also known as a radiation therapist. Radiographers are allied health professionals who work in both public healthcare and private healthcare and can be physically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computed Tomography
A computed tomography scan (CT scan), formerly called computed axial tomography scan (CAT scan), is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers or radiology technologists. CT scanners use a rotating X-ray tube and a row of detectors placed in a gantry to measure X-ray attenuations by different tissues inside the body. The multiple X-ray measurements taken from different angles are then processed on a computer using tomographic reconstruction algorithms to produce tomographic (cross-sectional) images (virtual "slices") of a body. CT scans can be used in patients with metallic implants or pacemakers, for whom magnetic resonance imaging (MRI) is contraindicated. Since its development in the 1970s, CT scanning has proven to be a versatile imaging technique. While CT is most prominently used in medical diagnosis, it can also be used to form images of non-living objects. The 1979 N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Screening (medicine)
In medicine, screening is a strategy used to look for as-yet-unrecognised conditions or risk markers. This testing can be applied to individuals or to a whole population without symptoms or signs of the disease being screened. Screening Public health intervention, interventions are designed to identify conditions which could at some future point turn into disease, thus enabling earlier intervention and management in the hope to reduce mortality and suffering from a disease. Although screening may lead to an earlier diagnosis, not all screening tests have been shown to benefit the person being screened; overdiagnosis, misdiagnosis, and creating a false sense of security are some potential Adverse effect (medicine), adverse effects of screening. Additionally, some screening tests can be inappropriately overused. For these reasons, a test used in a screening program, especially for a disease with low Incidence (epidemiology), incidence, must have good Sensitivity (tests), sensitivity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Scan
A bone scan or bone scintigraphy is a nuclear medicine imaging technique used to help diagnose and assess different bone diseases. These include cancer of the bone or metastasis, location of bone inflammation and fractures (that may not be visible in traditional X-ray images), and bone infection (osteomyelitis). Nuclear medicine provides functional imaging and allows visualisation of bone metabolism or bone remodeling, which most other imaging techniques (such as X-ray computed tomography, CT) cannot. Bone scintigraphy competes with positron emission tomography (PET) for imaging of abnormal metabolism in bones, but is considerably less expensive. Bone scintigraphy has higher sensitivity but lower specificity than CT or MRI for diagnosis of scaphoid fractures following negative plain radiography. History Some of the earliest investigations into skeletal metabolism were carried out by George de Hevesy in the 1930s, using phosphorus-32 and by Charles Pecher in the 1940s. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Detector
X-ray detectors are devices used to measure the flux, spatial distribution, spectrum, and/or other properties of X-rays. Detectors can be divided into two major categories: imaging detectors (such as photographic plates and X-ray film (photographic film), now mostly replaced by various digitizing devices like image plates or flat panel detectors) and dose measurement devices (such as ionization chambers, Geiger counters, and dosimeters used to measure the local radiation exposure, dose, and/or dose rate, for example, for verifying that radiation protection equipment and procedures are effective on an ongoing basis). X-ray imaging To obtain an image with any type of image detector the part of the patient to be X-rayed is placed between the X-ray source and the image receptor to produce a shadow of the internal structure of that particular part of the body. X-rays are partially blocked ("attenuated") by dense tissues such as bone, and pass more easily through soft tissues. Are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoroscopy
Fluoroscopy (), informally referred to as "fluoro", 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 () allows a surgeon to see the internal anatomy, structure and physiology, 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 medical diagnosis, 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 generator, X-ray source and a fluorescence, 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, bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
