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A bone scan is an imaging test that shows areas of increased or decreased bone turnover (metabolism.
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A bone scan is a diagnostic imaging procedure used to evaluate abnormalities involving bones and joints. A radionuclide is injected intravenously, and its distribution in the skeletal system is analyzed to detect certain diseases or conditions.
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A bone scan is an imaging test that uses a special camera to form images of your bones. It is used to diagnose bone problems, such as fractures, cancer, or infections, and joint problems such as arthritis. It is also used to check joint replacements.
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A bone scan is a diagnostic procedure used to evaluate abnormalities involving bones and joints. A radioactive substance is injected intravenously, and the image of its distribution in the skeletal system is analyzed to detect certain diseases or conditions.
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A bone lesion biopsy is the removal of a piece of bone or bone marrow for examination.
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Bone biopsy is the removal of a piece of bone for laboratory examination and analysis.
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During a physical examination, a health care provider studies a patient's body to determine the presence or absence of physical problems. A typical physical examination includes: Inspection (looking at the body; Palpation (feeling the body with hands; Auscultation (listening to sounds; Percussion (producing sounds.
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Magnetic resonance imaging (MRI) is a noninvasive way to take pictures of the body. Unlike x-rays and computed tomographic (CT) scans, which use radiation, MRI uses powerful magnets and radio waves. The MRI scanner contains the magnet. The magnetic field produced by an MRI is about 10 thousand times greater than the earth's. The magnetic field forces hydrogen atoms in the body to line up in a certain way (similar to how the needle on a compass moves when you hold it near a magnet. When radio waves are sent toward the lined-up hydrogen atoms, they bounce back, and a computer records the signal. Different types of tissues send back different signals. Single MRI images are called slices. The images can be stored on a computer or printed on film. One exam produces dozens or sometimes hundreds of images. For more information, see the specific MRI topics: Abdominal MRI; Chest MRI; Cranial MRI; Heart MRI; Lumbosacral spine MRI; Spine MRI.
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Cardiac nuclear imaging is also called a “perfusion scan.” A radioactive tracer is delivered into the bloodstream. Then a camera scans the tracer in the blood as it flows through the heart muscle.
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New MRI machines and new techniques result in images that show prostate cancer in much greater detail, allowing biopsies to be targeted more precisely, and thus cancer staging can be more accurate as well.
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Detailed information on magnetic resonance imaging, including how the image is performed and what happens following the procedure
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Magnetic Resonance Imaging (MRI)Magnetic resonance imaging(MRI) is a test that lets your doctor see detailed pictures of the inside of your body. MRI combines the use of strong magnets and radio waves to form an MRI image.Before Your TestMRI uses ...
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Studies have found that MRI tests used in addition to mammography detected more cancers in women at high risk for breast cancer. Women at average risk would not necessarily benefit from the additional testing.
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A Harvard Medical School physician answers your question about the safety of MRIs for those who have stents.
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When I had an MRI of my knee, I was told the test was dangerous for people who have metal devices in their bodies. Since then, I developed angina and my cardiologist put in a metal stent. If I need an MRI in the future, will I be able to get one?
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How safe is it for a baby who is 6 months old to have an MRI?
Claire McCarthy, M.D., is a senior medical editor for Harvard Health Publications. She is an instructor in pediatrics at Harvard Medical School, an attending physician at Children's Hospital of Boston, and co-director of the pediatrics department at Martha Eliot Health Center, a neighborhood health service of Children's Hospital. The author of two books, "Learning How the Heart Beats" and "Everyone's Children", Dr. McCarthy was a regular columnist for "Sesame Street Parents Magazine" from 1995 to 1998 and is currently a contributing editor for "Parenting Magazine".
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Persons with pacemakers cannot get an MRI because it conflicts with the pacemaker's function. Future pacemakers will likely be made MRI-safe, but this will probably take at least several more years.
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For women at high genetic risk, adding MRI screening to mammography may improve early detection of breast cancer.
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Is a regular MRI more accurate then an open MRI?
Diana Post, M.D., is an assistant professor of medicine at Harvard Medical School and a member of the Department of Medicine at Brigham and Women's Hospital.
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MRI produces a map of hydrogen atoms distributed in the body. Hydrogen is the simplest element known, the most abundant in biological tissue, and one that can be magnetically polarized. It will align itself within a strong magnetic field, like the needle of a compass. The earth's magnetic field is not strong enough to polarize a person's hydrogen atoms, but the superconducting magnet of an MRI machine can do this. The strength of the earth's magnetic field is approximately 1 gauss. Typical field strength of an MRI unit, with a superconducting magnet, is 1,500 gauss, expressed as 1.5 kilogauss or 1.5 Tesla units. This comprises the "magnetic" part of MRI. There are also low field units with 0.5 Tesla strength, often with open MRI units. Once a patient's hydrogen atoms have been aligned in the magnet, pulses of very specific radio wave frequencies jolt them out of alignment. The hydrogen atoms alternately absorb and emit radio wave energy, vibrating back and forth between their resting (polarized) state and their agitated (radio pulse) state. This comprises the "resonance" part of MRI. The patient does not detect this process. The MRI equipment detects the duration, strength, and source location of the signals emitted by the atoms as they relax. This data is translated into an image on a television monitor. The amount of hydrogen in diseased tissue differs from the amount in healthy tissue of the same type, making MRI particularly effective at identifying tumors and other lesions. In some cases, chemical agents such as gadolinium can be injected to improve the contrast between healthy and diseased tissue. A single MRI exposure produces a two-dimensional image of a slice through the entire target area. A series of these image slices closely spaced (usually less than half an inch [1.25 cm]) provides a virtual three-dimensional view of the area.
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Magnetic resonance imaging (MRI) is a unique and versatile medical imaging modality. Doctors can obtain highly refined images of the body's interior using MRI. By using strong magnetic fields and pulses of radio waves to manipulate the natural magnetic properties in the body, this technique produces images not possible with other diagnostic imaging methods. MRI is particularly useful for imaging the brain and spine, as well as the soft tissues of joints and the interior structure of bones. The entire body can be imaged using MRI, and the technology poses few known health risks.
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Magnetic resonance imaging (MRI) scanners rely on the principles of atomic nuclear-spin resonance. Using strong magnetic fields and radio waves, MRI collects and correlates deflections caused by atoms into images. MRIs (magnetic resonance imaging tests) offer relatively sharp pictures and allow physicians to see internal bodily structures with great detail. Using MRI technology, physicians are increasingly able to make diagnosis of serious pathology (e.g., tumors) earlier, and earlier diagnosis often translates to a more favorable outcome for the patient.
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Magnetic resonance imaging (MRI) is one of the newest diagnostic medical imaging technologies that uses strong magnets and pulses of radio waves to manipulate the natural magnetic properties in the body to generate a visible image. In the field of mental health, an MRI scan may be used when a patient seeks medical help for symptoms that could possibly be caused by a brain tumor. These symptoms may include headaches, emotional abnormalities, or intellectual or memory problems. In these cases, an MRI scan may be performed to "rule out" a tumor, so that other tests can be performed in order to establish an accurate diagnosis .
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Magnetic resonance imaging (MRI) is the newest, and perhaps most versatile, medical imaging technology available. Doctors can get highly refined images of the body's interior without surgery, using MRI. By using strong magnets and pulses of radio waves to manipulate the natural magnetic properties in the body, this technique makes better images of organs and soft tissues than those of other scanning technologies. MRI is particularly useful for imaging the brain and spine, as well as the soft tissues of joints and the interior structure of bones. The entire body is visible to the technique, which poses few known health risks.
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Magnetic resonance imaging (MRI) is one of the newest, and perhaps most versatile, medical imaging technology available. Doctors can get highly refined images of the body's interior without surgery using MRI. By using strong magnets and pulses of radio waves to manipulate the natural magnetic properties in the body, this technique makes better images of organs and soft tissues than those of other brain scanning technologies. MRI is particularly useful for imaging the brain and spine, as well as the soft tissues of joints and the interior structure of bones, as well as the liver. The entire body is visible with MRI, and the technique poses few known health risks.
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Magnetic resonance imaging (MRI) is a diagnostic imaging procedure that uses radio waves, a magnetic field, and a computer to generate images of the anatomy.
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People with certain kinds of pacemakers or ICDs can safely undergo an MRI, as long as a series of safety precautions is carefully followed.
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Detailed information on magnetic resonance imaging (MRI), including information on how the procedure is performed
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A computed tomography (CT) scan is an imaging method that uses x-rays to create cross-sectional pictures of the body. See also: Cranial CT scan; Lumbosacral spine CT scan; Orbit CT scan; Thoracic CT scan.
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Computed Tomography (CT)Computed tomography(CT) is a test that combines x-rays and computer scans. The result is a detailed picture that can show problems with soft tissues (such as the lining of your sinuses), organs (such as your kidneys or lung...
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Detailed information on ultrafast computed tomography scans, also called ultrafast CT scan or ultrafast CAT scan, including information on how the procedure is performed
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Detailed information on CT scan, including how the CT scan is performed and what happens after the procedure
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Detailed information on computed tomography scans, also called CT scan or CAT scan, including information on how the procedure is performed
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Detailed information on ultrafast computed tomography (CT) scan, including reasons for the procedure, risks of the procedure, what to expect, and discharge instructions
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Computed tomography (CT) scanning is a valuable diagnostic tool that provides physicians with views of internal body structures. During a CT scan, multiple x rays are passed through the body, producing cross-sectional images, or "slices, " on a cathode-ray tube (CRT), a device resembling a television screen. These images can then be preserved on film for examination.
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Computed tomography (CT), formerly referred to as computerized axial tomography (CAT), is a common diagnostic imaging procedure that uses x rays to generate images (slices) of the anatomy.
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Computed tomography (CT) scans are completed with the use of a 360-degree x-ray beam and computer production of images. These scans allow for cross-sectional views of body organs and tissues.
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Computed tomography scanning, also called CT scan, CAT scan, or computerized axial tomography, is a diagnostic tool that provides views of internal body structures using x rays. In the field of mental health, a CT scan may be used when a patient seeks medical help for symptoms that could possibly be caused by a brain tumor. These symptoms may include headaches, emotional abnormalities, or intellectual or memory problems. In these cases, a CT scan may be performed to "rule out" a tumor, so that other tests can be performed in order to establish an accurate diagnosis .
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Computed tomography (also known as CT, CT scan, CAT, or computerized axial tomography) scans use x rays to produce precise cross-sectional images of anatomical structures.
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What is the difference between a pelvic CT scan and an abdominal CT scan?
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Is there an alternative to iodine as a contrast medium in a CT scan?
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A biopsy is the removal of a small piece of tissue for laboratory examination.
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Ultrasound involves the use of high-frequency sound waves to create images of organs and systems within the body.
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Ultrasonography is a diagnostic technique that involves directing high frequency sound waves at tissues in the body to generate images of anatomical structures. Ultrasonography is also called sonography, diagnostic sonography, and echocardiography when it is used to image the heart.
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Detailed information on ultrasonograpy, also called sonography including information on how the procedure is performed
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Detailed information on ultrasound and the potential risks and benefits
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A thyroid ultrasound, or sonogram, is a diagnostic imaging technique used to evaluate the structure of the thyroid gland . The thyroid is an endocrine gland, which means that it releases its secretions directly into the bloodstream or lymph. It consists of two lobes located in the front of the neck that are connected by a thin band of tissue called the isthmus, which lies in front of the trachea (windpipe). Ultrasound procedures utilize high frequency sound waves to obtain images of various anatomical structures. Ultrasonography is the most common imaging technique used to evaluate the thyroid because it is not invasive, does not expose patients to radioactive materials, is less expensive than CT scans or MRI, and is more effective in detecting small lesions on the thyroid.
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My Ob/Gyn said they found fluid in the baby's kidneys during my 20-week ultrasound, so I have to have a level 2 ultrasound done. What does this mean?
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Diagnostic medical sonography, or ultrasound, is a technique using high frequency sound to create images of specific areas of the body to diagnose various pathologies. The diagnostic medical sonographer performs examinations, records anatomic condition and provides diagnostic information.
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Ultrasonography is the study of internal organs or blood vessels using high-frequency sound waves. The actual test is called an ultrasound scan or sonogram. Duplex ultrasonography uses Doppler technology to study blood cells moving through major veins and arteries. There are several types of ultrasound. Each is used in diagnosing specific parts of the body.
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The use of ultrasound to obtain diagnostic images is referred to as diagnostic sonography. Since diagnostic sonography utilizes a nonionizing form of energy, there are no known bioeffects. Thus, diagnostic sonography is applied to a large spectrum of clinical disorders, including obstetrical, gynecological, abdominal, urologic, pediatric, and vascular applications. Sonographic images are displayed in real time, which allows the study of dynamic processes. In addition, a method called Doppler interrogation, which uses ultrasound, can provide important information regarding blood flow. A RTHUR C. F LEISCHER ( SEE ALSO : Maternal and Child Health ; Pregnancy ; Prenatal Care )
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A biopsy describes the procedure that is used to obtain a very small piece of the target tissue. For some tissues, like the lining of the cheek, cells can be obtained just by scrapping the tissue surface. Other samples are collected using forceps that are positioned at the end of an optical device called an endoscope. The physician can view the tissue surface (such as the wall of the large intestine) through the endoscope and use the forceps to pluck tissue from the desired region of the surface. In other cases, the tissue sample needs to be collected as a "plug," using a large hypodermic needle. Examples of the latter include liver or kidney biopsy samples. Samples of muscles and nerves can also be obtained by cutting out a small piece of the target once an incision has been made. When a biopsy is obtained using a needle, the retrieval of a sample relies on the design of the needle and the energy of its insertion into the tissue. The needle used is a hollow tube with a sharp point capable of puncturing tissue. As the needle is driven deeper into a tissue following puncture, tissue will accumulate in the hollow tube. When the needle is withdrawn from the tissue, the plug of tissue remains in the needle tube and can be retrieved for analysis. Many biopsy samples are examined using a light microscope to look for abnormalities in the tissues cells. This examination can involve the staining of the sample to specifically detect target molecules. As well, samples can be used for various biochemical tests, and even to test for the presence and activity of particular genes. A biopsy can remove the entire target region (excisional biopsy) or can remove just a small portion of the target region (incisional biopsy). The latter can be done in three different ways, depending on the sample. A shave biopsy slices off surface tissue. Samples collected by piercing the tissue with a needle represent a punch biopsy. Finally, in fine needle aspiration, a needle is inserted and tissue is subsequently withdrawn into the needle using a syringe.
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Detailed information on biopsy, including the most common types of biopsy such as endoscopic biopsy, bone marrow biopsy, excisional biopsy, incisional biopsy, fine needle aspiration biopsy, punch biopsy, shave biopsy, and skin biopsy
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Biopsy is a diagnostic procedure in which a piece of tissue and/or cells are removed to be examined under a microscope by a pathologist.
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Detailed information on several of the different divisions of anatomical pathology, including biopsy, surgical pathology, cytology, and autopsy
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Image-Guided BiopsyAbiopsyis a small sample of tissue or fluid taken from the body. This sample can then be studied in a laboratory.
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If You Are Having a BiopsyQuestions for the doctor:What type of biopsy will I have?Why do I need a biopsy?
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Detailed information on biopsy and the biopsy report
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A medical procedure used to diagnose a condition. Most biopsies involve taking a small piece of skin or muscle under a local anesthetic. When the cells to be analyzed are accessible by needle, the biopsy specimen may be removed with a hollow aspiration needle, which is used to suck out the sample of cells. Aspirations are typically performed with local anesthesia; in addition, ultrasound imagery or other scanning devices may aid in locating the cells of interest. In cases where the cells are not accessible by needle, a longer tube called an endoscope may be inserted into the body with forceps attached for acquiring the specimen. Biopsy analysis is used in diagnosing cancer and muscular dystrophy.
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Tumor markers are a group of proteins, hormones, enzymes, receptors, and other cellular products that are overexpressed (produced in higher than normal amounts) by malignant cells. Tumor markers are usually normal cellular constituents that are present at normal or very low levels in the blood of healthy persons. If the substance in question is produced by the tumor, its levels will be increased either in the blood or in the tissue of origin.
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Cytology is the examination of individual cells and small clusters of cells, and may be used for the diagnosis and screening of diseases, including cancers. Cytology can also be referred to as cytopathology.
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A positron emission tomography (PET) scan is an imaging test that uses a radioactive substance (called a tracer) to look for disease in the body. Unlike magnetic resonance imaging (MRI) and computed tomography (CT) scans, which reveal the structure of and blood flow to and from organs, a PET scan shows how organs and tissues are working. See also: Bone scan; Nuclear ventriculography; Pulmonary ventilation/perfusion scan; Renal scan; Thyroid scan.
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Positron emission tomography (PET) is a highly specialized imaging technique using short-lived radiolabeled substances to produce powerful images of the body's biological function.
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Rather than showing the structure of a body part, PET images show the chemical function of an organ or tissue. PET can show changes in how an organ or tissue works. This can help your healthcare provider diagnose problems and develop a treatment plan for you.
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Detailed information on positron emission tomography (PET), including information on how PET scans are performed
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Positron emission tomography (PET) is a non-invasive scanning technique that utilizes small amounts of radioactive positrons (positively charged particles) to visualize body function and metabolism .
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The positron emission tomography ( PET ) unit is a device used to produce images of the body that reflect biochemical changes taking place in the body. Among the body imaging technologies used in medicine, the PET unit is characterized by its use of positron-emitting tracer substances. Because of its use of short-lived positron-emitting tracers, the PET unit can provide images of biochemical processes. This feature of PET technology distinguishes it from computer tomography (CT) and magnetic resonance imaging (MRI) technologies, which can provide only images of the structure of the body.
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PET Scan Use in Cancer Diagnosis and Treatment MonitoringFinding cancer at its earliest stage can give the best chance of being able to cure it. Different tests are used to find cancers and to help find out if the cancer has spread.
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Positron emission tomography (PET) is a non-invasive scanning technique that utilizes small amounts of radioactive positrons (positively charged particles) to visualize body function and metabolism.
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Positron emission tomography (PET) is a highly specialized imaging technique using short-lived radiolabeled substances to produce extremely high resolution images of the body's biological function.
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Positron emission tomography (PET) is a noninvasive scanning technique that utilizes small amounts of radioactive positrons (positively charged particles) to visualize body function and metabolism.
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Positron emission tomography (PET) is a scanning technique used in conjunction with small amounts of radiolabeled compounds to visualize brain anatomy and function. A PET scan showing brain activity while patient recognizes faces—left sides at left/right sides at right. Activity is prevalent in temporal lobe (bottom scans). ( Photo Researchers . Reproduced by permission.)
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Are the gamma rays of a PET scan dangerous?
Robert Shmerling, M.D., is associate physician and clinical chief of rheumatology at Beth Israel Deaconess Medical Center and an associate professor in medicine at Harvard Medical School. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program and has been a practicing rheumatologist for over 25 years.
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X-rays are a form of electromagnetic radiation, just like visible light. In a health care setting, a machines sends are individual x-ray particles, called photons. These particles pass through the body. A computer or special film is used to record the images that are created. Structures that are dense (such as bone) will block most of the x-ray particles, and will appear white. Metal and contrast media (special dye used to highlight areas of the body) will also appear white. Structures containing air will be black and muscle, fat, and fluid will appear as shades of gray.
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Detailed information on the most common procedures used for diagnostic radiology, including arteriogram, barium x-ray, computed tomography scan, fluoroscopy, intravenous pyelogram, magnetic resonance imaging, mammogram, ultrafast CT scan, ultrasound, x ra
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Detailed information on x-ray, including information on how the procedure is performed
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Body positions in x-ray exams are based on body part, suspected defect or disease, and condition of the patient. The radiographer, also known as the x-ray tech or more formally as the radiologic technologist, uses standardized body positions in performing an x-ray exam. Positions are learned by the radiographer according to body part in relation to body habitus, anatomical position and bisecting planes, and relationship of the body to the x-ray equipment.
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X rays are electromagnetic radiation that differentially penetrates structures within the body and creates images of these structures on photographic film or a fluorescent screen. These images are called diagnostic x rays.
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X rays are a type of radiation used in imaging andtherapy that uses short wavelength energy beams capable of penetrating most substances except heavy metals.
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What can doctors see on an X-ray? Large and small fractures are first on the list.
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