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| | MSN Encarta - Radiology |
 | | The use of ionizing radiation in diagnostic radiology involves passing a localized beam of X rays through the part of the body being examined. | | | In the century since RoentgenâÂÂs discovery, electromagnetic radiation in the form of ionizing radiation (alpha, beta, gamma, and X rays) has been the predominant energy source for diagnostic radiology. | | | Orthovoltage therapy has been largely replaced by megavoltage (cobalt, linear accelerator, and betatron) therapy ( see Particle Accelerators). |
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http://encarta.msn.com/encyclopedia_761551805/Radiology_medical_use_of_X_rays.html
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| | Proton Radiation Therapy: Technical Background |
| | Proton therapy provides the radiation oncologist with a highly precise method of placing radiation within a patient, when compared with conventional radiation therapy using X rays or electrons. | | | X rays can selectively destroy or inactivate cancer cells, leaving normal tissues largely intact; they permit preservation of normal tissues in quality-of-life therapy for cancer. | | | X rays have been studied for more than 100 years and are well understood. |
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http://www.llu.edu/proton/physician/technical.html
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| | Radiology |
| | A majority of these pictures are formed by passing a low or high level of x rays through the part of the body being examined, producing the static image on film. | | | By using radiant energy, which may take the form of x rays or other types of radiation, we are able to diagnose and treat many diseases and injuries. | | | Orthovoltage therapy has almost been completely replaced megavoltage(cobalt, linear accelerator, and betatron). |
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http://www.onlineessays.com/essays/tech/tech22.php
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| | Eryhthema: Historic studies |
| | Normalized dose-time relationships for skin tolerance and epidermoid cancer control with orthovoltage X-rays. | | | The right-hand column of this Table lists average factors by which doses are incremented for increase in overall time; linear regression of log-dose on log-time in this series than yields an estimate for the exponents in the power functions described. | | | In all the early studies, skin reactions were produced with "superficial therapy" units typically operating at.peak energies between 60 and 140 kilovolts (average photon energies were well below peak values). |
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http://www.radonc.uchicago.edu/lionel/erythema.html
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| | HistMedPhys.1983.paper.rtf |
| | \up6 13 \up0 Workers at this facility and at a similar one at the Saskatoon Cancer Clinic in Canada developed many aspects of the basic radiological physics for the therapeutic use of high-energy electrons and x rays. | | | The absorption of x rays via Compton scattering, coherent scattering, the photoelectric effect, pair production, and so forth, had been studied and characterized as functions of energy, atomic number and density. | | | Becquerel postulated that the intense phosphorescence of crystals of potassium uranyl sulfate exposed to sunlight might also be a source of x rays. |
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http://www.stanford.edu/group/mmdd/SiliconValley/Laughlin/HistMedPhys.1983.paper/HistMedPhys.1983.paper.rtf
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| | Mycosis Fungoides Foundation: Local X-ray and local and total skin Electron Beam radiation therapy |
| | Local x-ray therapy is still employed for treatment of localized CTCL lesions although it has been gradually supplanted by electron beam treatment since nearly all radiation therapy facilities have at least one therapy machine able to deliver electrons but often do not have any machines capable of delivering low energy orthovoltage x-rays. | | | Orthovoltage X-ray is still often employed to spot treat recurrent lesions but its penetration to underlying structures (vessels, muscle, bone marrow) is significant and its use over wide areas is impractical. | | | In addition, it is extremely rare for dermatologists to still offer Grenz ray (very low energy orthovoltage) treatment. |
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http://www.mffoundation.org/CTCL_treatments/electron.html
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| | From the Grand Rounds Archive at Baylor |
| | In diagnostic x-rays we are using every day for chest films and etc. are in very low energies, 15 to 50 kilovolts. | | | It was first discovered in 1895 by William Roentgen when he discovered what he called a "new kind of ray." About a year later at a conference he had Herr Von Kalager's hand placed in front of these rays before film and the first x-ray of a living object was obtained. | | | Now, what is important in radiation therapy is the differentiation between ionizing radiation and nonionizing radiation. |
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http://public.bcm.tmc.edu/oto/grand/10262000.html
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| | Department of Radiation Oncology |
| | Orthovoltage X-Ray Therapy X-ray therapy applied with a machine producing x-rays having a peak energy of 140 to 680 kVp. | | | Rotation Therapy External beam teletherapy in which the source of radiation moves circumferentially around the patient while being centered in the volume of interest. | | | Fractionation A technique of administering radiation therapy in multiple doses over a number of days or weeks to achieve a maximum therapeutic ratio. |
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http://www.xrt.upenn.edu/training/resident_glossery.html
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| | Xeriscaping, XML, X-Ray on MVP-Pages.com |
| | Among other applications, X rays are used in diagnostic medicine and in the study of crystal structure (see X-ray crystallography). | | | X rays provide a image of the body's interior when they pass through it and strike a photographic plate or fluorescent screen; denser materials absorb more X rays and appear brighter. | | | Discovered in 1895 by Wilhelm Roentgen, X rays are produced by the impact of high-energy electrons (of several thousands of eV) on a metal anode in a highly evacuated glass bulb. |
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http://www.mvp-pages.com/x.html
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| | CENTIGRAY.COM - Resources for the Radiation Oncology Professional |
| | Most patients had PBPC-Tx with granulocyte colony-stimulating factor (G-CSF), and the median time to neutrophil count 500 x 10(6) l(-1) and platelet count >20 x 10(9) l(-1) without transfusion independence was 10 (range 8-25) and 13 (8-60) days, respectively. | | | Amlashi SF, Riffaud L, Brassier G, Morandi X. Service de Neurochirurgie, Hopital Pontchaillou, Rennes, France. | | | MATERIAL AND METHODS: Reports in the literature spanning 60 years of radiation therapy, including orthovoltage, megavoltage and recently modern high-precision treatments, were reviewed with respect to visual function, survival, prognostic factors, dose prescriptions, target volumes, and treatment techniques. |
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http://centigray.com/medulloblastoma.htm
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| | Danbury Engineering Inc. World Wide Suppliers of RadiationTherapy Systems |
| | For years our focus has been on supporting the Radiation Therapy Department, providing New, Used, and Refurbished systems, primarily Superficial and Orthovoltage X-ray Therapy Systems, as well as Parts, Maintenance, and Emergency Service. | | | We offer quality products, deliver and install them ourselves, and stand behind everything we sell. |
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http://www.danburyengineering.com
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| | Breast Cancer Incidence Higher |
| | The procedures included fluoroscopy, portable radiography, routine radiography, multifilm procedures, dental x rays, radium therapy, orthovoltage, cobalt-60, betatron, other radiographic teletherapy, other radioisotope therapy, diagnostic radioisotopes, microwave/ultrasound diathermy, diagnostic ultrasound and CAT scan (Doody, et al. | | | The second analysis found no increased risk of breast cancer associated with performing a variety of procedures or the number of times they were performed. |
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http://www.arrt.org/website/newsite/New/WN_Hlth_Stdy.htm
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| | Treatment-External Beam-Darren Kahler, Ph.D., University of Florida Department of Radiation Oncology |
| | External beam therapy is a common technique used to treat malignant tumors or benign lesions through the delivery of high doses of X rays or electrons. | | | X rays and electrons of different energies allow the radiation oncologist to customize the treatment according to a patientÂs specific needs. | | | At the University of Florida Shands Cancer Center, a variety of machines provide patients with external-beam radiation therapy. |
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http://www.med.ufl.edu/radonc/Eq_EBRT-Kahler.htm
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| | Orthovoltage X-rays - Wikipedia, the free encyclopedia |
| | Orthovoltage X-rays have an energy in the range of 200-500 kV. | | | When used to treat patients, radiation oncologists find that they penetrate to a useful depth of about 4-6cm. | | | Historically, as radiation machines were improved in the 1930-40s, the beam energy (and so its penetration) were increased. |
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http://www.wikipedia.org/wiki/Orthovoltage
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| | Department of Radiology Short Clerkship: Lectures |
| | X rays and gamma rays are indirectly ionizing; they do not produce chemical/ biological changes themselves. | | | X rays and gamma rays used in diagnostic radiology and/or radiation oncology are examples of electromagnetic radiation. | | | One may think of these rays as packets of energy or photons; their energy will depend on wavelength. |
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http://www.radiology.uiowa.edu/Radshortclerkship/RadShortClkship/LectureNotes/Osborne-.htm
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| | eMedicine - Radiation Therapy, General Principles : Article by Gary J Schreiber, MD |
| | The dual nature of electromagnetic radiation is used to explain its wave and particulate behavior. | | | When a need for skin irradiation exists (eg, skin involvement by the tumor or skin as the target in the treatment of basal cell cancers), the technique is adjusted so that a brisk skin reaction is produced. | | | Even with megavoltage treatment, skin tanning and dry desquamation can occur. |
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http://www.emedicine.com/ent/topic247.htm
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| | Welcome to St. David's Healthcare Partnership's Web Site |
| | In external radiation therapy, rays are directed at the tumor from outside the body. | | | The rays or particles enter the cell's nucleus, interact with water present in the nucleus, and form a free radical called hydroxyl radical. | | | In fact, the presence of oxygen is so important that patients who smoke, and therefore lower the oxygen level to their tumor, suffer from a 50% reduction in the ability of the radiation to kill the cancer. |
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http://ehc.healthgate.com/getcontent.asp?siteid=1A0B79C6-1489-11D4-81D4-00508B1249D5&docid=/cancer/treatment/radiation
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| | Exradin Ion Chambers |
| | It is used for assessing pinpoint radiation fields for orthovoltage, x-rays and stereotactic and superficial skin therapy. | | | Gy/C. This new, ultra small ion chamber has a 2D collecting area of only 3.4 mm x 3.4 mm and a collecting volume of 0.007 cc. | | | Micropoint Chamber at only 0.007cc is designed primarily for applications like IMRT and stereotactic surgery, which use cobalt and higher energy beams. |
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http://www.seedos.com/exradin%20ion%20chambers.htm
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| | Radiation Therapy |
| | In veterinary medicine, radiotherapy is used to treat tumors and non-neoplastic processes and is generally delivered by fractionated external beam irradiation. | | | Orthovoltage units - Orthovoltage units are relatively low energy external beam radiotherapy machines, x-ray machines operating in the range of 150 - 500 kilovolts peak (kVp). | | | In a typical orthovoltage beam, the maximum dose is at the skin surface and falls to 90% at approximately 2 cm of depth. |
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http://www.ivis.org/special_books/Braund/forrest/chapter_frm.asp?LA=1
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| | 1982 Beryllium Related Journal Articles |
| | The results have been compared with data obtained after irradiation with single doses of 250kV X rays. | | | In the skin a low RBE value of approximately 1.2 was obtained for the early (3-9 week) epithelial reaction. | | | Acute skin reactions were scored and compared with those from orthovoltage therapy with comparable beam geometry. |
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http://www.dimensional.com/~mhj/1982.html
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| | Untitled Document |
| | Sievert (Sv) = WR x Gy Dose effective: WT – tissue weighting factor | | | Grenz Ray (low kVp units) for skin therapy |
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http://www.medphysics.wisc.edu/~vrm/contents.htm
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| | glossery |
| | The use of radiation, usually x-rays or gamma rays, to kill tumour cells. | | | A technician who gives radiotherapy prescribed by a radiation oncologist. | | | Breast reconstruction using skin and fat from the abdomen carried on the rectus abdominis muscle, which runs down the middle of your abdomen. |
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http://www.bcexperience.org/glossary.html
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| | The BIRD Clinic - L3 Strontium-90 Tx |
| | In avian species, surgical excision has been the mainstay of cancer treatment, namely because most radiotherapy and chemotherapy regimens are cost prohibitive to pet owners or may result in significant patient morbidity. | | | A 10 x 10 x 6-mm mass was observed extending from the location of the uropygial gland. | | | Nymphicus hollandicus) was referred for a 15 x 9 x 8-mm mass growing out of an ulcer in the epidermis covering the left lobe of the uropygial gland. |
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http://www.thebirdclinic.net/517264.html
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| | HistoryAcceler.1984.paper.rtf |
| | The betatron energy of 22 MeV \par \par \par \par "History of Accelerators"\tab 13\tab E. Ginzton\par \page provided deep penetration for x-ray therapy and techniques had been developed to extract the beam for electron therapy39. | | | The distribution of positions and angles of all the rays making up the electron beam from the accelerator are \par \par \par \par "History of Accelerators"\tab 20\tab E. Ginzton\par \page reproduced at the output of an achromatic bend magnet independent of the energies of these individual rays. | | | Field sizes to 15 cm x 15 cm were provided at unflattened dose rate to 110 cGy/minute at 1 meter. |
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http://www.stanford.edu/group/mmdd/SiliconValley/Ginzton-Nunez/HistoryAcceler.1984.paper/HistoryAcceler.1984.paper.rtf
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| | CO1 Syllabus - Physics |
| | Description of an x- or gamma-ray beam (quality, energy, intensity, size) | | | It is essential that during the course of instruction there should be demonstrations of therapeutic and related equipment and procedures to illustrate the importance of the subject to radiotherapeutic practice. | | | For each of the following understand the nature of the effect and its dependence on the properties of the irradiated material (eg density, atomic number), its variation with energy and the relative importance in therapy and imaging. |
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http://www.rcr.ac.uk/onexam.asp?PageID=484
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| | CHAPTER 8, Dosimetry : From Bomb, to Kerma, to Internal Organ-Dose, RADIATION-INDUCED CANCER FROM LOW-DOSE EXPOSURE |
| | Orthovoltage x rays are the usual reference radiation, but gamma rays from 137-Cesium and 60-Cobalt have also been widely used as reference radiations. | | | The definition of RBE means that, if one rad of neutron exposure produces the same level of biological effect as 10 rads of orthovoltage X-rays, then the RBE value for neutrons would be 10, relative to the X-rays. | | | At Hiroshima and Nagasaki, the extremely early gamma rays and neutrons, transported from the explosion-region outward, dominate the doses received by survivors who were located at various distances from the hypocenter of the bomb. |
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http://www.ratical.com/radiation/CNR/RIC/chp8F.html
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| | applied dosimetry |
| | The interaction of single beams of X and gamma rays with a scattering medium. | | | The course deals with techniques, dosimetry, and equipment used for external and internal irradiation of patients with sealed radiation sources. | | | Radiotherapy with particle beams: electrons, pions, neutrons, heavy charged particles. |
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http://www.medphys.mcgill.ca/mptexts/courses/ad.html
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| | HGSA Medical Policy: R-4I - Radiation Oncology: Radiation Therapy Treatment and Complementary Services |
| | 5 treatment sessions = code 77427 x 1 | | | Simulation is accomplished through the use of equipment such as a dedicated simulator, linear accelerator, cobalt unit, orthovoltage x-ray machine, diagnostic x-ray fluoroscopy unit, or other equipment used to establish areas to be treated. | | | Example: 8 fractions were reported and payment for code 77427 x 2 was made, if 2 additional fractions are furnished by the same physician, no additional payment is made for those 2 fractions. |
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http://www.hgsa.com/professionals/policy-draft/r4i.html
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| | ECVDI Examinations |
| | Bursography of the distal sesamoid bone and tendon sheath contrast media studies in the equine patient | | | Common tumor types from these systems should be understood in terms of local invasiveness, metastatic potential and common metastatic appearance and described radiographic appearances based on the literature related to veterinary medicine. | | | The basic physical aspects of different radiotherapy units (Orthovoltage, Cobalt-60, Linear accelarotor) |
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http://www.vet.gla.ac.uk/EVDI/ec-syll.htm
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