Download [2021] X-ray
Mark Reed
X-rays are a type of radiation called electromagnetic waves. X-ray imaging creates pictures of the inside of your body. The images show the parts of your body in different shades of black and white. This is because different tissues absorb different amounts of radiation. Calcium in bones absorbs x-rays the most, so bones look white. Fat and other soft tissues absorb less and look gray. Air absorbs the least, so lungs look black.
The most familiar use of x-rays is checking for fractures (broken bones), but x-rays are also used in other ways. For example, chest x-rays can spot pneumonia. Mammograms use x-rays to look for breast cancer.
When you have an x-ray, you may wear a lead apron to protect certain parts of your body. The amount of radiation you get from an x-ray is small. For example, a chest x-ray gives out a radiation dose similar to the amount of radiation you're naturally exposed to from the environment over 10 days.
Computed tomography (CT): Combines traditional x-ray technology with computer processing to generate a series of cross-sectional images of the body that can later be combined to form a three-dimensional x-ray image. CT images are more detailed than plain radiographs and give doctors the ability to view structures within the body from many different angles. Learn more about CT here.
Fluoroscopy: Uses x-rays and a fluorescent screen to obtain real-time images of movement within the body or to view diagnostic processes, such as following the path of an injected or swallowed contrast agent. For example, fluoroscopy is used to view the movement of the beating heart, and, with the aid of radiographic contrast agents, to view blood flow to the heart muscle as well as through blood vessels and organs. This technology is also used with a radiographic contrast agent to guide an internally threaded catheter during cardiac angioplasty, which is a minimally invasive procedure for opening clogged arteries that supply blood to the heart.
Single-frame x-ray tomosynthesis (SFXT): Conventional x-ray radiography generates a single two-dimensional image, which is created by imaging a single plane at a single time point. X-ray tomosynthesis, on the other hand, uses multiple images, which are then reconstructed to generate more information, such as a three-dimensional image. Unlike CT imaging, where the source/detector physically travels at least 180 degrees around the patient, tomosynthesis uses a limited rotational angle and takes fewer images (requiring less radiation and less expense). Current tomosynthesis approaches, however, generate a static snapshot of the tissue of interest and do not allow for real-time imaging.
Imaging to guide lung biopsies: Lung cancer is the leading cause of cancer-related mortality in the United States, and analyzing lesions found in the lungs is a way to screen for the disease and to guide treatment. For a biopsy, one method to obtain lung tissue is through a bronchoscopy, where a thin tube is passed through the nose or mouth and guided into the lungs. However, obtaining tissues of interest remains difficult, as locating and visualizing such lesions is challenging. To overcome these limitations, researchers have developed a new, cost-effective chest x-ray tomosynthesis system that can generate high-resolution, real-time images of the lungs, which would allow for improved visualization during a transbrochial biopsy. In addition to being less expensive and easier to use than standard CT-based approaches, this x-ray technique is stationary and does not require any physical motion of the x-ray source or detector. Further, this method uses low doses of radiation, which would be beneficial for patients who require multiple biopsies. This x-ray system is currently being optimized for pre-clinical large animal evaluation.
Manufacturers of diagnostic x-ray systems intended for human use are required to file reports of assembly upon installation of a certifiable system or component(s). The report of assembly (FDA Form 2579) represents the assemblers certification that the system or component(s) are of the type called for by the Standard (i.e., certified), have been assembled according to the instructions provided by the manufacturer, and meets the requirements of the applicable Federal standards contained in 21 CFR 1020.30 through 1020.33. Reports must be submitted to the purchaser and, where applicable, to the State agency responsible for radiation protection within 15 days following completion of the assembly. Contact Information for State agencies is available on the website of the Conference of Radiation Control Program Directors (CRCPD), the organization of state radiation regulators. (If the pop-up information block includes "State Medical Contacts," select it and then select the "Form 2579" tab.)
The Maine Radiation Control Program - X-ray section is staffed by Bob Stilwell and Dan Quesada. The x-ray section registers approximately 1060 x-ray facilities . There is an annual registration fee per x-ray machine and a requirement for periodic inspections. These inspections are performed by third party Qualified Experts who are approved by the agency.
Medical radiation machines make up the largest man-made source of exposure to the public. In 1958, the state Board of Health began a program to inspect radiation machines. Today over 20,000 facilities, including hospitals, doctors' offices, universities, and corporations, have registered more than 62,000 x-ray machines with the department.
The radiation machine program works to reduce exposure to workers and the public from machines that emit radiation for medical, scientific, educational, and industrial purposes. The program accomplishes this by:
Tables and graphs of the photon mass attenuation coefficient μ/ρ and the mass energy-absorption coefficient μen/ρ are presented for all of the elements Z = 1 to 92, and for 48 compounds and mixtures of radiological interest. The tables cover energies of the photon (x-ray, gamma ray, bremsstrahlung) from 1 keV to 20 MeV. The μ/ρ values are taken from the current photon interaction database at the National Institute of Standards and Technology, and the μen/ρ values are based on the new calculations by Seltzer described in Radiation Research 136, 147 (1993). These tables of μ/ρ and μen/ρ replace and extend the tables given by Hubbell in the International Journal of Applied Radiation and Isotopes 33, 1269 (1982).
Dual-energy x-ray absorptiometry (DEXA) has sustained a niche for measuring bone mineral density since its approval by the Food and Drug Administration (FDA) for clinical use in 1988. The Bone Mass Measurements act in 1998 solidified its validity in light of other diagnostic modalities such as chemical analysis, direct dissection and ashing, quantitative ultrasonography, and later on against CT/MRI images. DEXA is comparatively inexpensive with notably shorter scan times and radiation exposure compared to other imaging options, and there is a long-standing consensus regarding guidelines for interpreting DEXA images. This activity reviews the indications, contraindications of DEXA and highlights the role of the interprofessional team in the management of patients with osteoporosis.
Dual-energy x-ray absorptiometry (DEXA) has sustained a niche for measuring bone mineral density since its approval by the Food and Drug Administration (FDA) for clinical use in 1988. The Bone Mass Measurements act in 1998 solidified its validity in light of other diagnostic modalities such as chemical analysis, direct dissection and ashing, quantitative ultrasonography, and later on against CT/MRI images. DEXA is comparatively inexpensive with notably shorter scan times and radiation exposure compared to other imaging options, and there is a long-standing consensus regarding guidelines for interpreting DEXA images.
X-rays can be obtained at select ChristianaCare imaging locations without an appointment - walk-ins are always welcome. For more information on locations that offer x-ray services, please check our Imaging Locations page.
CellRad systems are plug-n-play, cabinet x-ray units for cell and tissue irradiation. These dedicated benchtop systems bring experiments from incubator to x-ray in one step, allowing you to irradiate samples without compromising sterility or security.
An x-ray is a type of radiation used to create a picture of the inside of the body. As x-ray beams pass through your body they are absorbed differently by various structures in the body, such as bones and soft tissues, and this is used to create an image. X-ray imaging is also known as radiography.
Some types of x-ray use injected or swallowed contrast dye (contrast media) to improve the images so it is important that you tell the doctor if you have any kidney disease or if you have previously had any allergic reaction to contrast media. Also, tell the doctor if you have difficulty taking a deep breath and holding it.
Contrast dye (also known as contrast medium) is a substance that is sometimes used during plain x-ray, CT scanning, angiography or other tests. It helps to improve the contrast in x-ray images, making it easier to distinguish between normal and diseased or damaged areas. It may be given to you orally (by mouth) or by injection.
A plain x-ray is painless and usually takes less than 15 minutes. It can be done in a hospital or private radiology practice. X-rays are done by a radiographer or medical imaging technologist. The images are reviewed by a a specialist medical doctor called a radiologist.
Yes. An x-ray uses a small amount of radiation to create an image. Some types of x-ray, such as CT scanning and angiography, use higher doses of radiation than plain x-rays. The amount of radiation used is unlikely to cause any serious problems, but if you are concerned you should talk to your doctor.
An X-ray fluorescence (XRF) spectrometer is an x-ray instrument used for routine, relatively non-destructive chemical analyses of rocks, minerals, sediments and fluids. It works on wavelength-dispersive spectroscopic principles that are similar to an electron microprobe (EPMA). However, an XRF cannot generally make analyses at the small spot sizes typical of EPMA work (2-5 microns), so it is typically used for bulk analyses of larger fractions of geological materials. The relative ease and low cost of sample preparation, and the stability and ease of use of x-ray spectrometers make this one of the most widely used methods for analysis of major and trace elements in rocks, minerals, and sediment.
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