Required/Required when applicable/Optional
... *Registration using a soft tissue surrogate for the tumor is recommended. *Free-breathing CTs are not to be used as reference images for 4D CBCT IGRT process **Clearly visible anatomical markers are acceptable as fiducials, e.g. inserted radio-opage markers or Lipiodol from prior TACE treatment. Whe ...
... *Registration using a soft tissue surrogate for the tumor is recommended. *Free-breathing CTs are not to be used as reference images for 4D CBCT IGRT process **Clearly visible anatomical markers are acceptable as fiducials, e.g. inserted radio-opage markers or Lipiodol from prior TACE treatment. Whe ...
Dose assessment in Nuclear Medicine Therapy
... arising from the probability distribution of dose values (absorbed dose or BED) given by the normalized DVH. Sgouros G et al Semin nucl Med 2008 ...
... arising from the probability distribution of dose values (absorbed dose or BED) given by the normalized DVH. Sgouros G et al Semin nucl Med 2008 ...
Effects on radiation oncology treatments involving
... be required in the rare case. Radiation therapy delivery for breast and lung then become particularly problematic, since there is not just one device obstacle, but bilateral obstacles. Particle accelerator beam angle adjustments can compensate to some degree to avoid the device and still target the ...
... be required in the rare case. Radiation therapy delivery for breast and lung then become particularly problematic, since there is not just one device obstacle, but bilateral obstacles. Particle accelerator beam angle adjustments can compensate to some degree to avoid the device and still target the ...
Radiation Safety in Pediatric Imaging - RPOP
... 6-year period, ED patients, ages 0 to 17 years Pediatric ED patient volume increased by 2% Distribution of triage acuity remained relatively stable Head CT increased 23%, Cervical spine CT 366%, Chest CT 435%, Abdominal CT 49%, miscellaneous CT 96% Most pronounced in adolescents ages 13 to 17 years ...
... 6-year period, ED patients, ages 0 to 17 years Pediatric ED patient volume increased by 2% Distribution of triage acuity remained relatively stable Head CT increased 23%, Cervical spine CT 366%, Chest CT 435%, Abdominal CT 49%, miscellaneous CT 96% Most pronounced in adolescents ages 13 to 17 years ...
ACR Technical Standard for Diagnostic Medical Physics
... most appropriate imaging procedures to prevent unwarranted radiation exposure. Facilities should have and adhere to policies and procedures that require varying ionizing radiation examination protocols (plain radiography, fluoroscopy, interventional radiology, CT) to take into account patient body h ...
... most appropriate imaging procedures to prevent unwarranted radiation exposure. Facilities should have and adhere to policies and procedures that require varying ionizing radiation examination protocols (plain radiography, fluoroscopy, interventional radiology, CT) to take into account patient body h ...
DETERMINATION OF CT-TO-DENSITY CONVERSION
... plot shows scattered data points but its behavior can be predicted to consist of 2 linear relationships for CT value ranges from ⫺1000 to 0 and above 0. In addition, it should be recognized that the slope of these straight lines and the point of inflection change somewhat from CT scanner to CT scann ...
... plot shows scattered data points but its behavior can be predicted to consist of 2 linear relationships for CT value ranges from ⫺1000 to 0 and above 0. In addition, it should be recognized that the slope of these straight lines and the point of inflection change somewhat from CT scanner to CT scann ...
Radiation Protection – Chapter 23, Bushberg
... Reducing field size limits the patient volume exposed to primary beam, reduces the amount of scatter and thus radiation dose to adjacent organs (scatter being reduced improves image contrast) Gonadal shielding can be used to protect the gonads from primary radiation when the shadow of the shield ...
... Reducing field size limits the patient volume exposed to primary beam, reduces the amount of scatter and thus radiation dose to adjacent organs (scatter being reduced improves image contrast) Gonadal shielding can be used to protect the gonads from primary radiation when the shadow of the shield ...
Reducing Your Risk of Radiation Exposure and
... radioactive isotopes that pose a risk in an incident or accident is vital to reducing exposure risk. Fuel rods are generally composed of heavy fissile material such as Uranium-235 and Plutonium-239 in the form of metal oxides. These elements can be made to undergo a nuclear fission reaction, which s ...
... radioactive isotopes that pose a risk in an incident or accident is vital to reducing exposure risk. Fuel rods are generally composed of heavy fissile material such as Uranium-235 and Plutonium-239 in the form of metal oxides. These elements can be made to undergo a nuclear fission reaction, which s ...
Diagnostic Medical Imaging Radiation Exposure and Risk of
... occupational protracted exposures to lowdose ionizing radiation and calculated an excess relative risk of leukemia of 0.19 at 0.1 Gy. This is lower than that noted in the LSS cohort but can be explained by differences in exposure types: single-event vs chronic protracted exposure. Further epidemiolo ...
... occupational protracted exposures to lowdose ionizing radiation and calculated an excess relative risk of leukemia of 0.19 at 0.1 Gy. This is lower than that noted in the LSS cohort but can be explained by differences in exposure types: single-event vs chronic protracted exposure. Further epidemiolo ...
News Letter - Association of Medical Physicists of India
... reduce the effect of concomitant dose arising during IGRT procedures. The scientific paper titled "The management of imaging dose during image-guided radiotherapy: Report of the AAPM Task Group 75" (https://www.aapm.org/pubs/reports/RPT_95.pdf) enumerates the details of imaging dose that are to be c ...
... reduce the effect of concomitant dose arising during IGRT procedures. The scientific paper titled "The management of imaging dose during image-guided radiotherapy: Report of the AAPM Task Group 75" (https://www.aapm.org/pubs/reports/RPT_95.pdf) enumerates the details of imaging dose that are to be c ...
Cone Beam 3D Imaging
... technology. NewTom VGi takes an image at every degree of rotation, 360° rotation = 360 images, increasing the range of possibilities for image manipulation. It couples a revolutionary flat panel x-ray detector technology with a very small focal spot (0.3 mm), ...
... technology. NewTom VGi takes an image at every degree of rotation, 360° rotation = 360 images, increasing the range of possibilities for image manipulation. It couples a revolutionary flat panel x-ray detector technology with a very small focal spot (0.3 mm), ...
25.1 Nuclear Radiation
... Nuclear reactions, which account for radioactivity, differ from chemical reactions in a number of important ways. In chemical reactions, atoms tend to attain stable electron configurations by losing electrons or sharing electrons. In nuclear reactions, the nuclei of unstable isotopes, called radiois ...
... Nuclear reactions, which account for radioactivity, differ from chemical reactions in a number of important ways. In chemical reactions, atoms tend to attain stable electron configurations by losing electrons or sharing electrons. In nuclear reactions, the nuclei of unstable isotopes, called radiois ...
Radiation therapy
Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is therapy using ionizing radiation, generally as part of cancer treatment to control or kill malignant cells. Radiation therapy may be curative in a number of types of cancer if they are localized to one area of the body. 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 that focuses on radiotherapy is called radiation oncology.Radiation therapy is commonly applied to the cancerous tumor because of its ability to control cell growth. Ionizing radiation works by damaging the DNA of cancerous tissue leading to cellular death. To spare normal tissues (such as skin or organs which radiation must pass through to treat the tumor), shaped radiation beams are aimed from several angles of exposure to intersect at the tumor, providing a much larger absorbed dose there than in the surrounding, healthy tissue. Besides the tumour itself, the radiation fields may also include the draining lymph nodes if they are clinically or radiologically involved with tumor, or if there is thought to be a risk of subclinical malignant spread. It is necessary to include a margin of normal tissue around the tumor to allow for uncertainties in daily set-up and internal tumor motion. These uncertainties can be caused by internal movement (for example, respiration and bladder filling) and movement of external skin marks relative to the tumor position.Radiation oncology is the medical specialty concerned with prescribing radiation, and is distinct from radiology, the use of radiation in medical imaging and diagnosis. Radiation may be prescribed by a radiation oncologist with intent to cure (""curative"") or for adjuvant therapy. It may also be used as palliative treatment (where cure is not possible and the aim is for local disease control or symptomatic relief) or as therapeutic treatment (where the therapy has survival benefit and it can be curative). It is also common to combine radiation therapy with surgery, chemotherapy, hormone therapy, immunotherapy or some mixture of the four. Most common cancer types can be treated with radiation therapy in some way.The precise treatment intent (curative, adjuvant, neoadjuvant, therapeutic, or palliative) will depend on the tumor type, location, and stage, as well as the general health of the patient. Total body irradiation (TBI) is a radiation therapy technique used to prepare the body to receive a bone marrow transplant. Brachytherapy, in which a radiation source is placed inside or next to the area requiring treatment, is another form of radiation therapy that minimizes exposure to healthy tissue during procedures to treat cancers of the breast, prostate and other organs.Radiation therapy has several applications in non-malignant conditions, such as the treatment of trigeminal neuralgia, acoustic neuromas, severe thyroid eye disease, pterygium, pigmented villonodular synovitis, and prevention of keloid scar growth, vascular restenosis, and heterotopic ossification. The use of radiation therapy in non-malignant conditions is limited partly by worries about the risk of radiation-induced cancers.