CT Dose Reduction Applications - Journal of the American College
... been enormous [1]. This growth in volume, combined with the increasing use of CT in radiation-sensitive populations (ie, children, young adults, and pregnant female patients), has been an impetus for CT manufacturers to develop a number of radiation dose reduction tools. Furthermore, there has been ...
... been enormous [1]. This growth in volume, combined with the increasing use of CT in radiation-sensitive populations (ie, children, young adults, and pregnant female patients), has been an impetus for CT manufacturers to develop a number of radiation dose reduction tools. Furthermore, there has been ...
How to Create a World Class Dose Reduction Program
... Once the dose reduction committee has been formed, the next step is to assign responsibilities and set a timeline. Establishing a healthy dose reduction program at most facilities is about a one year project, with some larger or more complex facilities taking up to two years. With respect to assigni ...
... Once the dose reduction committee has been formed, the next step is to assign responsibilities and set a timeline. Establishing a healthy dose reduction program at most facilities is about a one year project, with some larger or more complex facilities taking up to two years. With respect to assigni ...
Has Transit Dosimetry Come Of Age
... ...during the last few years rather intensive efforts have led to the development of techniques that produce images using high-energy high X- rays directly. As a result, electronic portal imaging devices (EPIDs) are becoming available to cancer radiotherapy. In some systems, a small fraction of the ...
... ...during the last few years rather intensive efforts have led to the development of techniques that produce images using high-energy high X- rays directly. As a result, electronic portal imaging devices (EPIDs) are becoming available to cancer radiotherapy. In some systems, a small fraction of the ...
Inclusion of the dose from kilovoltage cone beam CT in the radiation
... We have modeled the kV CBCT beam from a Varian OBI system on a Trilogy linear accelerator 共Varian Medical Systems, Palo Alto, CA兲 in the Philips PINNACLE treatment planning system v8.0 共Philips Medical Systems, Milpitas, CA兲. The OBI system has been extensively described elsewhere.1,10 In brief, the ...
... We have modeled the kV CBCT beam from a Varian OBI system on a Trilogy linear accelerator 共Varian Medical Systems, Palo Alto, CA兲 in the Philips PINNACLE treatment planning system v8.0 共Philips Medical Systems, Milpitas, CA兲. The OBI system has been extensively described elsewhere.1,10 In brief, the ...
Imaging in Radiotherapy, IAEA Consultant`s meeting report
... There are two main methods of CT simulation. The first involves the alignment of the patient, often with the aid of a CT scout view to ensure appropriate skeletal alignment, with the marking of the patient isocenter with a tattoo and overlaid radioopaque marker prior to the scan. The second approach ...
... There are two main methods of CT simulation. The first involves the alignment of the patient, often with the aid of a CT scout view to ensure appropriate skeletal alignment, with the marking of the patient isocenter with a tattoo and overlaid radioopaque marker prior to the scan. The second approach ...
- Wiley Online Library
... tools that are validated with specific acceptability criteria and tolerance levels to ensure that hardware and software functions safely and reliably perform as expected. Vendors may provide instructions on how to perform the measurements and how to use the tools for clinical sites. Users establish ...
... tools that are validated with specific acceptability criteria and tolerance levels to ensure that hardware and software functions safely and reliably perform as expected. Vendors may provide instructions on how to perform the measurements and how to use the tools for clinical sites. Users establish ...
organ and effective doses from a multidetector computed
... effective doses from CT examination are the important quantities to assess radiation risk. The objective of this study is to calculate the organ and effective doses from patient data. The beam data was collected for 30 cases of patient over 20 years old underwent 64 slices GE VCT MDCT scanner in the ...
... effective doses from CT examination are the important quantities to assess radiation risk. The objective of this study is to calculate the organ and effective doses from patient data. The beam data was collected for 30 cases of patient over 20 years old underwent 64 slices GE VCT MDCT scanner in the ...
Clinical commissioning and use of the Novalis Tx linear accelerator
... pairs of 5 mm outer leaves, which produce a maximum beam width of 220 mm orthogonal to the leaf motion direction at the isocenter (Table 3). Along the leaf motion direction, both the maximum retracted and over-travel distances are 200 mm. Therefore, the maximum field size the MLC can realize is 400 ...
... pairs of 5 mm outer leaves, which produce a maximum beam width of 220 mm orthogonal to the leaf motion direction at the isocenter (Table 3). Along the leaf motion direction, both the maximum retracted and over-travel distances are 200 mm. Therefore, the maximum field size the MLC can realize is 400 ...
Optimisation in general radiography (PDF Available)
... terms of stochastic effects in the long term [14]. It equates the uniform dose to the whole body that would have a similar level of risk and takes account of doses to radio-sensitive organs in different parts of the body. However, the effective dose can only be derived from calculations. These are b ...
... terms of stochastic effects in the long term [14]. It equates the uniform dose to the whole body that would have a similar level of risk and takes account of doses to radio-sensitive organs in different parts of the body. However, the effective dose can only be derived from calculations. These are b ...
Comparison of Patient Localization Accuracy Between Stereotactic
... In IGRT, the beam alignment information derived from images used for the targeting of tumors is less dependent on image quality because it is dependent on imaging frequency to observe the constancy of patient localization before/during treatment. In radiotherapy process, a large number of the images ...
... In IGRT, the beam alignment information derived from images used for the targeting of tumors is less dependent on image quality because it is dependent on imaging frequency to observe the constancy of patient localization before/during treatment. In radiotherapy process, a large number of the images ...
Academic Program Recommendations for Graduate Degrees in Medical Physics Physicists Committee
... latter include Computational Skills, Medical Ethics, Statistics, Safety, and Clinical Research and Scientific Communication. As mentioned, the former are essential to all medical physics training and serve to act as a basis for more subspecialty training. The latter incorporate a knowledge base need ...
... latter include Computational Skills, Medical Ethics, Statistics, Safety, and Clinical Research and Scientific Communication. As mentioned, the former are essential to all medical physics training and serve to act as a basis for more subspecialty training. The latter incorporate a knowledge base need ...
AAPM Report 197 - Louisiana State University
... latter include Computational Skills, Medical Ethics, Statistics, Safety, and Clinical Research and Scientific Communication. As mentioned, the former are essential to all medical physics training and serve to act as a basis for more subspecialty training. The latter incorporate a knowledge base need ...
... latter include Computational Skills, Medical Ethics, Statistics, Safety, and Clinical Research and Scientific Communication. As mentioned, the former are essential to all medical physics training and serve to act as a basis for more subspecialty training. The latter incorporate a knowledge base need ...
Acceptability requirements for X-ray equipment used in health care
... hinders identifying differences in contrast. There must not be any disturbing glare from light sources when the monitor is off. ...
... hinders identifying differences in contrast. There must not be any disturbing glare from light sources when the monitor is off. ...
Image Guided Radiation Therapy: Benefits and Risks, Certainties
... “Image-guided radiotherapy (IGRT) makes use of many different imaging techniques, using modalities ranging from portal imaging to fluoroscopy to megavoltage cone-beam CT and following regimens as simple as a single setup image or as complex as intrafraction tumor tracking.”1 AAPM TG-75 (2007) ...
... “Image-guided radiotherapy (IGRT) makes use of many different imaging techniques, using modalities ranging from portal imaging to fluoroscopy to megavoltage cone-beam CT and following regimens as simple as a single setup image or as complex as intrafraction tumor tracking.”1 AAPM TG-75 (2007) ...
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.