1 Comparison of Effective Dose and Lifetime Risk of Cancer
... SPECT/CT has become common place in clinical imaging and a major role for CT is for the attenuation correction (AC) of SPECT data in myocardial perfusion imaging (MPI) [1, 2]. The benefits of CTAC in MPI are well known and many national and international professional organisations recommend its use ...
... SPECT/CT has become common place in clinical imaging and a major role for CT is for the attenuation correction (AC) of SPECT data in myocardial perfusion imaging (MPI) [1, 2]. The benefits of CTAC in MPI are well known and many national and international professional organisations recommend its use ...
NDAC TITLE 114 ND MEDICAL IMAGING and RADIATION
... licensed practitioner, that is responsible for the administration of ionizing radiation to humans for diagnostic, therapeutic or research purposes. 11. "Certification organization" means a national certification organization that specializes in the certification and registration of medical imaging a ...
... licensed practitioner, that is responsible for the administration of ionizing radiation to humans for diagnostic, therapeutic or research purposes. 11. "Certification organization" means a national certification organization that specializes in the certification and registration of medical imaging a ...
Study on the Computed Tomography Dose Index volume
... scanning. Axial scanning mode requires two alternate stages; data acquisition and patient positioning. During data acquisition stage, only the x-ray tube rotates around the patient while during patient positioning stage, no data are acquired and patient is transported to the next prescribe scanning ...
... scanning. Axial scanning mode requires two alternate stages; data acquisition and patient positioning. During data acquisition stage, only the x-ray tube rotates around the patient while during patient positioning stage, no data are acquired and patient is transported to the next prescribe scanning ...
AAPM REPORT NO. 54 STEREOTACTIC RADIOSURGERY Report
... is extremely important to understand the importance of quality assurance in every step of the SRS treatment process. As with brachytherapy, the dose with SRS is administered in one or a few applications. However, the dose rate for SRS is such that the dose is typically delivered in less than one hou ...
... is extremely important to understand the importance of quality assurance in every step of the SRS treatment process. As with brachytherapy, the dose with SRS is administered in one or a few applications. However, the dose rate for SRS is such that the dose is typically delivered in less than one hou ...
Radiation exposure and thyroid cancer: a review
... unexposed subjects from the same geographical region (3,14). The prevalence of hypothyroidism, thyroid nodules, and thyroid carcinoma in exposed subjects increased with the radiation dose to the thyroid gland. Females were at a higher risk (3.7 fold) of developing a thyroid nodule than males, and th ...
... unexposed subjects from the same geographical region (3,14). The prevalence of hypothyroidism, thyroid nodules, and thyroid carcinoma in exposed subjects increased with the radiation dose to the thyroid gland. Females were at a higher risk (3.7 fold) of developing a thyroid nodule than males, and th ...
AAPM-RSNA Physics Tutorial for Residents: Typical Patient
... Factors affecting patient dose in all x-ray imaging modalities include beam energy, filtration, collimation, patient size, and image processing. In conventional radiography, the most important determinant of acceptable patient dose is use of the highest peak kilovoltage that results in diagnostic im ...
... Factors affecting patient dose in all x-ray imaging modalities include beam energy, filtration, collimation, patient size, and image processing. In conventional radiography, the most important determinant of acceptable patient dose is use of the highest peak kilovoltage that results in diagnostic im ...
Cone Beam Computed Tomography in Endodontics: An Overview.
... Large Volume Equipment: Large volume tomographs acquire image volume of over 8x8 cm, generally from 12x12 cm upto 18x22cm. Here the radiation dose is higher and the image quality is lower when compared with the small volume equipment. These can generate multilayer reconstructions with 2 dimensional ...
... Large Volume Equipment: Large volume tomographs acquire image volume of over 8x8 cm, generally from 12x12 cm upto 18x22cm. Here the radiation dose is higher and the image quality is lower when compared with the small volume equipment. These can generate multilayer reconstructions with 2 dimensional ...
Code of Practice for Diagnostic and Interventional Radiology: Draft
... Effective dose – the tissue-weighted sum of equivalent doses in all specified tissues and organs of the body. Equivalent dose – the radiation-weighted dose in a tissue or organ of the body. Facility – the location at which radiological and ancillary equipment is installed, used, handled or stored. I ...
... Effective dose – the tissue-weighted sum of equivalent doses in all specified tissues and organs of the body. Equivalent dose – the radiation-weighted dose in a tissue or organ of the body. Facility – the location at which radiological and ancillary equipment is installed, used, handled or stored. I ...
ORGAN MOTION AND IMAGE GUIDANCE IN RADIATION THERAPY
... Organ motion and inaccurate patient positioning may compromise radiation therapy outcome. With the aid of image guidance, it is possible to allow for a more accurate organ motion and motion control study, which could lead to the reduction of irradiated healthy tissues and possible dose escalation to ...
... Organ motion and inaccurate patient positioning may compromise radiation therapy outcome. With the aid of image guidance, it is possible to allow for a more accurate organ motion and motion control study, which could lead to the reduction of irradiated healthy tissues and possible dose escalation to ...
[2017.96] Interactive Exhibit on Imaging Updates for Staging and
... celiac and splenic arteries in combination with a distal pancreatectomy. The gastroduodenal artery (GDA) must be preserved, because perfusion of the liver is by retrograde flow through this vessel to the common hepatic artery. ...
... celiac and splenic arteries in combination with a distal pancreatectomy. The gastroduodenal artery (GDA) must be preserved, because perfusion of the liver is by retrograde flow through this vessel to the common hepatic artery. ...
reduced radiation exposure and iodine load at low tube kilovoltage
... or pelvis, the mean estimated effective dose can still reach 15 mSv on average (range, 13–40 mSv) as reported by Mettler et al. [16] . Other authors have published lower observed effective radiation doses ranging between 3 and 5 mSv [14,17] . As the benefit:risk ratio for using CT is high and the h ...
... or pelvis, the mean estimated effective dose can still reach 15 mSv on average (range, 13–40 mSv) as reported by Mettler et al. [16] . Other authors have published lower observed effective radiation doses ranging between 3 and 5 mSv [14,17] . As the benefit:risk ratio for using CT is high and the h ...
Quality assurance for image-guided radiation therapy
... was primarily designed for noninvasive, frameless, fractionated stereotactic treatments of brain and lung cancers. The distinguishing feature of the integrated CT-linac system is the moving gantry CT scanner, which is mounted on rails (henceforth referred to as “CT-on-rails”) so that it can move acr ...
... was primarily designed for noninvasive, frameless, fractionated stereotactic treatments of brain and lung cancers. The distinguishing feature of the integrated CT-linac system is the moving gantry CT scanner, which is mounted on rails (henceforth referred to as “CT-on-rails”) so that it can move acr ...
Radiation protection for X-Ray systems _ed2
... (this means that radiation levels in controlled areas that are occupied routinely by radiation workers must be such that: first, no radiation worker is occupationally exposed to more than 20 mSv per year; and second, non-public person receives more than 1mSv per year). The system of radiation dose l ...
... (this means that radiation levels in controlled areas that are occupied routinely by radiation workers must be such that: first, no radiation worker is occupationally exposed to more than 20 mSv per year; and second, non-public person receives more than 1mSv per year). The system of radiation dose l ...
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.