3D dose verification for advanced radiotherapy
... planning, dose calculation, treatment plan transfer or for detecting differences between planned and actual delivered energy fluence distributions of treatment fields. In Chapter 3 a method is described that measures the dose delivered by the linear accelerator with an EPID and reconstructs the 3D d ...
... planning, dose calculation, treatment plan transfer or for detecting differences between planned and actual delivered energy fluence distributions of treatment fields. In Chapter 3 a method is described that measures the dose delivered by the linear accelerator with an EPID and reconstructs the 3D d ...
portal dosimetry in radiotherapy
... measurements can be done prior to treatment (pre‐treatment measurements) and during treatment (in vivo measurements) using several dose verification devices. Diodes, thermoluminescent dosimeters (TLDs) and metal oxide semiconductor field‐effect transistors (MOSFETs)15‐18 ...
... measurements can be done prior to treatment (pre‐treatment measurements) and during treatment (in vivo measurements) using several dose verification devices. Diodes, thermoluminescent dosimeters (TLDs) and metal oxide semiconductor field‐effect transistors (MOSFETs)15‐18 ...
Cone Beam Ct for Dental and Maxillofacial Radiology
... implications are well recognised and action is taken by the European Commission to address them. This is done in two ways – by maintaining an up-to-date legislative framework1 and by supporting research on radiation protection in medicine – both under the framework of the Treaty establishing the Eur ...
... implications are well recognised and action is taken by the European Commission to address them. This is done in two ways – by maintaining an up-to-date legislative framework1 and by supporting research on radiation protection in medicine – both under the framework of the Treaty establishing the Eur ...
MICHIGAN DEPARTMENT OF PUBLIC HEALTH RADIATION
... charge of the ions of 1 sign produced in air when all the electrons (negatrons and positrons) liberated by photons in a volume element of air having mass dm are completely stopped in air. The special unit of exposure is the roentgen. (3) "Exposure rate" means the exposure per unit of time, such as R ...
... charge of the ions of 1 sign produced in air when all the electrons (negatrons and positrons) liberated by photons in a volume element of air having mass dm are completely stopped in air. The special unit of exposure is the roentgen. (3) "Exposure rate" means the exposure per unit of time, such as R ...
Piranha Reference Manual - English - 5.5G
... If installed according to accompanying documents, the product is intended to be used together with all diagnostic X-ray equipment except for: - therapeutical X-ray sources. - X-ray equipment with tube potential below 18 kV. - X-ray equipment on which the instrument cannot be mounted properly, e.g. e ...
... If installed according to accompanying documents, the product is intended to be used together with all diagnostic X-ray equipment except for: - therapeutical X-ray sources. - X-ray equipment with tube potential below 18 kV. - X-ray equipment on which the instrument cannot be mounted properly, e.g. e ...
Anniversary Paper: Development of x
... Image artifacts also occupied an important body of early research. The deleterious effect of the polychromatic spectrum of conventional x-ray sources on CT image quality— the so-called beam hardening effect—was recognized and described early in this era, along with a number of correction algorithms. ...
... Image artifacts also occupied an important body of early research. The deleterious effect of the polychromatic spectrum of conventional x-ray sources on CT image quality— the so-called beam hardening effect—was recognized and described early in this era, along with a number of correction algorithms. ...
A literature review of electronic portal imaging for
... Quality control procedures before and during treatment can potentially ensure a high level of accuracy necessary for treatments designed to achieve adequate tumour control and reduction of normal tissue complications. As a result of the high number of patients being treated in radiotherapy departmen ...
... Quality control procedures before and during treatment can potentially ensure a high level of accuracy necessary for treatments designed to achieve adequate tumour control and reduction of normal tissue complications. As a result of the high number of patients being treated in radiotherapy departmen ...
An X-ray Source Model and Characterization Method for Computing
... Introduction With an expected 187,600 new cases and 75,500 related deaths in 2013, cancer is a leading cause of death in Canada, having caused 29.8% of all deaths in 2009[32]. The main treatment options for cancer are radiation therapy, surgery, and chemotherapy. Two-thirds of all cancer patients wi ...
... Introduction With an expected 187,600 new cases and 75,500 related deaths in 2013, cancer is a leading cause of death in Canada, having caused 29.8% of all deaths in 2009[32]. The main treatment options for cancer are radiation therapy, surgery, and chemotherapy. Two-thirds of all cancer patients wi ...
Calculation, verification and monitoring of patient dose in Diagnostic
... the patient’s heart is at the iso centre and the c-arm rotates around this central point. In this position the couch top is at 60cm from the focus. This is defined as the point of reference for calculating patient entrance skin dose. The detector is then moved as close to the patient as possible, ty ...
... the patient’s heart is at the iso centre and the c-arm rotates around this central point. In this position the couch top is at 60cm from the focus. This is defined as the point of reference for calculating patient entrance skin dose. The detector is then moved as close to the patient as possible, ty ...
Radiological Protection in Cone Beam Computed Tomography
... recommendations and guidance on application of principles of radiological protection it establishes. This has been done through specific publications on the various uses of ionising radiation in medicine in various imaging and therapeutic modalities. This is in addition to the reports published by t ...
... recommendations and guidance on application of principles of radiological protection it establishes. This has been done through specific publications on the various uses of ionising radiation in medicine in various imaging and therapeutic modalities. This is in addition to the reports published by t ...
Structure of the Atom - The American Association of Physicists in
... Radiation Units Q4. The absorbed dose to the ovaries from a limited CT exam of 8 cm length, with a 2 cm thickness contiguous acquisition with the ovaries in the beam, is 8 mGy. If the study is expanded in length to cover 16 cm instead, which of the following descriptors of dose is correct? A. The d ...
... Radiation Units Q4. The absorbed dose to the ovaries from a limited CT exam of 8 cm length, with a 2 cm thickness contiguous acquisition with the ovaries in the beam, is 8 mGy. If the study is expanded in length to cover 16 cm instead, which of the following descriptors of dose is correct? A. The d ...
Development and Implementation of an Anthropomorphic Pediatric
... Proton therapy is gaining acceptance as a cancer treatment modality, as it allows for dose deposition to the target volume while sparing the surrounding healthy tissue. This technique is advantageous for craniospinal pediatric patients, as it reduces the radiation side effects that can occur. The pu ...
... Proton therapy is gaining acceptance as a cancer treatment modality, as it allows for dose deposition to the target volume while sparing the surrounding healthy tissue. This technique is advantageous for craniospinal pediatric patients, as it reduces the radiation side effects that can occur. The pu ...
SADMFR guidelines for the use of cone-beam computed
... On January 24th and 25th, 2011 the SADMFR convened for the diagnose their own radiographs. However, in medical radiology first consensus workshop to establish indications and contra this is considered a comprehensive process performed by differ- indications for CBCT in dental medicine. This first c ...
... On January 24th and 25th, 2011 the SADMFR convened for the diagnose their own radiographs. However, in medical radiology first consensus workshop to establish indications and contra this is considered a comprehensive process performed by differ- indications for CBCT in dental medicine. This first c ...
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.