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Image-guided Radiation Therapy
Image-guided radiation therapy (IGRT) is the process of frequent imaging, during a course of radiation treatment, used to direct the treatment, position the patient, and compare to the pre-therapy imaging from the treatment plan. Immediately prior to, or during, a treatment fraction, the patient is localized in the treatment room in the same position as planned from the reference imaging dataset. An example of IGRT would include comparison of a cone beam computed tomography (CBCT) dataset, acquired on the treatment machine, with the computed tomography (CT) dataset from planning. IGRT would also include matching planar kilovoltage (kV) radiographs or megavoltage (MV) images with digital reconstructed radiographs (DRRs) from the planning CT. This process is distinct from the use of imaging to delineate targets and organs in the planning process of radiation therapy. However, there is a connection between the imaging processes as IGRT relies directly on the imaging modalities from pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interventional Radiology
Interventional radiology (IR) is a medical specialty that performs various minimally-invasive procedures using medical imaging guidance, such as Fluoroscopy, x-ray fluoroscopy, CT scan, computed tomography, magnetic resonance imaging, or ultrasound. IR performs both diagnostic and therapeutic procedures Minimally invasive procedure, through very small incisions or body orifices. Diagnostic IR procedures are those intended to help make a diagnosis or guide further medical treatment, and include image-guided biopsy of a tumor or injection of an Radiocontrast agent, imaging contrast agent into a hollow structure, such as a blood vessel or a Bile duct, duct. By contrast, Therapy, therapeutic IR procedures provide direct treatment—they include catheter-based medicine delivery, medical device placement (e.g., stents), and angioplasty of narrowed structures. The main benefits of IR techniques are that they can reach the deep structures of the body through a body orifice or tiny incisi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Rays
A gamma ray, also known as gamma radiation (symbol ), is a penetrating form of electromagnetic radiation arising from high energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. It consists of the shortest wavelength electromagnetic waves, typically shorter than those of X-rays. With frequencies above 30 exahertz () and wavelengths less than 10 picometers (), gamma ray photons have the highest photon energy of any form of electromagnetic radiation. Paul Villard, a French chemist and physicist, discovered gamma radiation in 1900 while studying radiation emitted by radium. In 1903, Ernest Rutherford named this radiation ''gamma rays'' based on their relatively strong penetration of matter; in 1900, he had already named two less penetrating types of decay radiation (discovered by Henri Becquerel) alpha rays and beta rays in ascending order of penetrating power. Gamma rays from radioactive decay are in the energy range ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface-guided Radiation Therapy
Surface-guided radiation therapy (SGRT) (sometimes referred to as Surface-image Guided Radiation Therapy) is the process of using 3D imaging to position and track movement of radiation therapy patients during treatment. Goals and clinical benefits SGRT can help to improve the safety, effectiveness and efficiency of radiation therapy treatments, by offering guidance across every step of the radiation therapy workflow, including simulation, planning, treatment and dose visualisation. Developed as an advancement to image-guided radiation therapy, SGRT relies on 3D imaging as opposed to an x-ray. SGRT uses cameras to feed data into a software program linked to the linear accelerator delivering the radiation. Each camera uses a projector and image sensors to create a 3D surface model of a patient, by projecting a red light containing a pseudo-random speckle pattern on their skin. The pattern allows the SGRT system to reference thousands of points on the skin, acting as virtual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiation Therapy
Radiation therapy or radiotherapy (RT, RTx, or XRT) is a therapy, treatment using ionizing radiation, generally provided as part of treatment of cancer, cancer therapy to either kill or control the growth of malignancy, malignant cell (biology), cells. It is normally delivered by a linear particle accelerator. Radiation therapy may be cure, curative in a number of types of cancer if they are localized to one area of the body, and have not metastasis, spread to other parts. It may also be used as part of adjuvant therapy, to prevent tumor recurrence after surgery to remove a primary malignant tumor (for example, early stages of breast cancer). Radiation therapy is synergistic with chemotherapy, and has been used before, during, and after chemotherapy in susceptible cancers. The subspecialty of oncology concerned with radiotherapy is called radiation oncology. A physician who practices in this subspecialty is a radiation oncologist. Radiation therapy is commonly applied to the canc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Positron Emission Tomography
Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging purposes, depending on the target process within the body, such as: * Fluorodeoxyglucose ( 18F">sup>18FDG or FDG) is commonly used to detect cancer; * 18Fodium fluoride">sup>18Fodium fluoride (Na18F) is widely used for detecting bone formation; * Oxygen-15 (15O) is sometimes used to measure blood flow. PET is a common imaging technique, a medical scintillography technique used in nuclear medicine. A radiopharmaceutical—a radioisotope attached to a drug—is injected into the body as a tracer. When the radiopharmaceutical undergoes beta plus decay, a positron is emitted, and when the positron interacts with an ordinary electron, the tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Radiography
Radiography is an imaging technology, 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 X-ray detector, detector (either photographic film or a digital detector). The generation of flat two-dimensional images by this technique is called Projection radiography, projectional radiography. In computed tomography (C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Commission On Radiation Units And Measurements
International is an adjective (also used as a noun) meaning "between nations". International may also refer to: Music Albums * ''International'' (Kevin Michael album), 2011 * ''International'' (New Order album), 2002 * ''International'' (The Three Degrees album), 1975 *''International'', 2018 album by L'Algérino Songs * The Internationale, the left-wing anthem * "International" (Chase & Status song), 2014 * "International", by Adventures in Stereo from ''Monomania'', 2000 * "International", by Brass Construction from ''Renegades'', 1984 * "International", by Thomas Leer from ''The Scale of Ten'', 1985 * "International", by Kevin Michael from ''International'' (Kevin Michael album), 2011 * "International", by McGuinness Flint from ''McGuinness Flint'', 1970 * "International", by Orchestral Manoeuvres in the Dark from '' Dazzle Ships'', 1983 * "International (Serious)", by Estelle from '' All of Me'', 2012 Politics * Internationalism (politics) * Political internationa ... [...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] |
Cyberknife (device)
The CyberKnife system is a radiation therapy device manufactured by Accuray. The system is used to deliver radiosurgery for the treatment of benign tumors, malignant tumors and other medical conditions. Device The device consists of a small linear accelerator attached to a robotic arm, along with an integrated image guidance system. During treatment, the image guidance system captures 3D images, tracks the movement of tumors, and guides the robotic arm to accurately aim the treatment beam at the moving tumor. The system is designed for stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT). The system is also used for select 3D conformal radiotherapy (3D-CRT) and intensity modulated radiation therapy (IMRT). History The development of the system began in 1989 with contributions from John R. Adler, a surgeon at Stanford University, and Peter and Russell Schonberg of Schonberg Radiation Corporation. This work expanded upon earlier efforts in the 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CT Scanner
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] |
Compton Effect
Compton scattering (or the Compton effect) is the quantum theory of high frequency photons scattering following an interaction with a charged particle, usually an electron. Specifically, when the photon hits electrons, it releases loosely bound electrons from the outer valence shells of atoms or molecules. The effect was discovered in 1923 by Arthur Holly Compton while researching the scattering of X-rays by light elements, and earned him the Nobel Prize in Physics in 1927. The Compton effect significantly deviated from dominating classical theories, using both special relativity and quantum mechanics to explain the interaction between high frequency photons and charged particles. Photons can interact with matter at the atomic level (e.g. photoelectric effect and Rayleigh scattering), at the nucleus, or with just an electron. Pair production and the Compton effect occur at the level of the electron. When a high frequency photon scatters due to an interaction with a charged part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alvin J
''Alvin'' (DSV-2) is a crewed deep-ocean research submersible owned by the United States Navy and operated by the Woods Hole Oceanographic Institution (WHOI) of Woods Hole, Massachusetts. The original vehicle was built by General Mills' Electronics Group in Minneapolis, Minnesota. Named to honor the prime mover and creative inspiration for the vehicle, Allyn Vine, ''Alvin'' was commissioned on June 5, 1964. The submersible is launched from the deep submergence support vessel , which is also owned by the U.S. Navy and operated by WHOI. The submersible has made more than 5,200 dives, carrying two scientists and a pilot, observing the lifeforms that must cope with super-pressures and move about in total darkness, as well as exploring the wreck of ''Titanic''. Research conducted by ''Alvin'' has been featured in nearly 2,000 scientific papers. Design ''Alvin'' was designed as a replacement for bathyscaphes and other less maneuverable oceanographic vehicles. Its more nimble de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
