Light comes from the sun in the form of electromagnetic waves. There are different types of electromagnetic waves, and some are visible and some are not. The ones we are most familiar with are radio waves, ultraviolet rays, and microwaves. It is these invisible waves of electromagnetic energy that give us the use of X-rays. The X-ray was accidentally discovered by Wilhelm Roentgen, a professor of physics in Wurzburg, Bavaria in during an experiment.
In , the first radiology department was established at the Glasgow Royal Infirmary. Soon, X-ray machines were being used for many things, such as diagnosing fractures in the bones and to locate bullets during WWI.
This one discovery advanced the field of medicine in a very big way. To be able to see the structure inside a person without blood loss from an incision was revolutionary. But how does an X-ray work? Well, think back to your grade school science class. Remember photons and electrons — atoms and molecules and nuclei? An X-ray is produced when a negatively charged electrode is heated by electricity and electrons are released, thereby producing energy. That energy is directed toward a metal plate, or anode, at high velocity and an X-ray is produced when the energy collides with the atoms in the metal plate.
Pictures may be taken from different views e. X-rays expose you to a small amount of radiation — about the amount you get from a cross-country flight. The amount of radiation in an X-ray is too small to cause you any harm. Radiation in large doses can cause cancer and birth defects. Inform the doctor if you are or may be pregnant. The radiologist will promptly review your images and communicate directly with your referring doctor, who in turn will discuss the results with you.
If you have further questions about this diagnostic test, contact the doctor that ordered the test or visit Radiologyinfo. We comply with the HONcode standard for trustworthy health information. X-rays can also be used to guide doctors or surgeons during certain procedures. For example, during a coronary angioplasty — a procedure to widen narrowed arteries near the heart — X-rays can be used to help guide a catheter a long, thin, flexible tube along one of your arteries.
You don't usually need to do anything special to prepare for an X-ray. You can eat and drink as normal beforehand and can continue taking your usual medications. However, you may need to stop taking certain medications and avoid eating and drinking for a few hours if you're having an X-ray that uses a contrast agent see contrast X-rays below.
For all X-rays, you should let the hospital know if you're pregnant. X-rays aren't usually recommended if you're pregnant unless it's an emergency. It's a good idea to wear loose comfortable clothes, as you may be able to wear these during the X-ray.
Try to avoid wearing jewellery and clothes containing metal such as zips , as these will need to be removed. During an X-ray, you'll usually be asked to lie on a table or stand against a flat surface so that the part of your body being examined can be positioned in the right place.
The X-ray machine, which looks like a tube containing a large light bulb, will be carefully aimed at the part of the body being examined by the radiographer. They will operate the machine from behind a screen or from the next room. The X-ray will last for a fraction of a second.
You won't feel anything while it's carried out. While the X-ray is being taken, you'll need to keep still so the image produced isn't blurred. More than one X-ray may be taken from different angles to provide as much information as possible. In some cases, a substance called a contrast agent may be given before an X-ray is carried out. This can help show soft tissues more clearly on the X-ray. These types of X-rays may need special preparation beforehand and will usually take longer to carry out.
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