precautions while using x rays

Spectrum of the X rays emitted by an X ray tube with a rhodium target, operated at 60 kV. The smooth, continuous curve is due to bremsstrahlung, and the spikes are characteristic K lines for rhodium atoms. Since X rays are emitted by electrons, they can be generated by an X ray tube, a vacuum tube that uses a high voltage to accelerate the electrons released by a hot cathode to a high velocity. The high velocity electrons collide with a metal target, the anode, creating the X rays.[17] In medical X ray tubes the target is usually tungsten or a more crack resistant alloy of rhenium (5%) and tungsten (95%), but sometimes molybdenum for more specialized applications, such as when softer X rays are needed as in mammography. In crystallography, a copper target is most common, with cobalt often being used when fluorescence from iron content in the sample might otherwise present a problem.

If the electron has enough energy it can knock an orbital electron out of the inner electron shell of a metal atom, and as a result electrons from higher energy levels then fill up the vacancy and X ray photons are emitted. This process produces an emission spectrum of X rays at a few discrete frequencies, sometimes referred to as the spectral lines. The spectral lines generated depend on the target (anode) element used and thus are called characteristic lines. Usually these are transitions from upper shells into K shell (called K lines), into L shell (called L lines) and so on.

This is radiation given off by the electrons as they are scattered by the strong electric field near the high Z (proton number) nuclei. These X rays have a continuous spectrum. The intensity of the X rays increases linearly with decreasing frequency, from zero at the energy of the incident electrons, the voltage on the X ray tube.

X ray detectors vary in shape and function depending on their purpose. Imaging detectors such as those used for radiography were originally based on photographic plates and later photographic film but are now mostly replaced by various digital detector types such as image plates or flat panel detectors. For radiation protection direct exposure hazard is often evaluated using ionization chambers, while dosimeters are used to measure the radiation dose a person has been exposed to. X ray spectra can be measured either by energy dispersive or wavelength dispersive spectrometers.

A radiograph is an X ray image obtained by placing a part of the patient in front of an X ray detector and then illuminating it with a short X ray pulse. Bones contain much calcium, which due to its relatively high atomic number absorbs x rays efficiently. This reduces the amount of X rays reaching the detector in the shadow of the bones, making them clearly visible on the radiograph.

Fluoroscopy is an imaging technique commonly used by physicians or radiation therapists to obtain real time moving images of the internal structures of a patient through the use of a fluoroscope. In its simplest form, a fluoroscope consists of an X ray source and fluorescent screen between which a patient is placed. However, modern fluoroscopes couple the screen to an X ray image intensifier and CCD video camera allowing the images to be recorded and played on a monitor. This method may use a contrast material. Examples include cardiac catheterization (to examine for coronary artery blockages) and barium swallow (to examine for esophageal disorders).

The use of X rays as a treatment is known as radiation therapy and is largely used for the management (including palliation) of cancer; it requires higher radiation energies than for imaging alone. X radiation (composed of X rays) is a form of electromagnetic radiation. Most X rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3?1016 Hz to 3?1019 Hz) and energies in the range 100 eV to 100 keV. X ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X radiation is referred to with terms meaning R

Abdominal radiograph of a pregnant woman, a procedure that should be performed only after proper assessment of benefit versus risk. Diagnostic X rays (primarily from CT scans due to the large dose used) increase the risk of developmental problems and cancer in those exposed. X rays are classified as a carcinogen by both the World Health Organization s International Agency for Research on Cancer and the U.S. government. It is estimated that 0.4% of current cancers in the United States are due to computed tomography (CT scans) performed in the past and that this may increase to as high as 1.5 2% with 2007 rates of CT usage.

X rays use small amounts of radiation. The level of exposure is considered safe for adults. However, it is not considered safe for a developing fetus. Be sure to tell your doctor before the procedure if you are pregnant or believe you could be pregnant. Your doctor may suggest a different testing method that does not use radiation, such as an MRI. If you are having an X ray due to a traumatic event that caused pain and possibly a broken bone, you may experience additional pain during the X ray. The test requires you to adjust your body so that clear images can be taken. This may cause you discomfort. If you are worried, you can ask your doctor for pain medicine prior to your X ray.

X rays are standard procedures and involve almost no preparation from the patient. Depending on the area under review, you may want to wear loose, comfortable clothing that you can easily move around in. You may also be asked to change into a hospital gown for the test. You will be instructed to remove any jewelry and other metallic items from your body before the X ray is taken. You should always tell your doctor if you have any metal implants from prior surgeries. These can block the X rays from passing through your body.If your test requires contrast dye, a doctor or nurse will give it to you as an injection, an edema, or a pill to swallow before the test. If your X ray is examining your intestines, your doctor may tell you to fast for a certain amount of time beforehand, or to clear out your bowels.