Healthy Living

Everything You Need to Know About X-Rays

Everything You Need to Know About X-Rays

Key Takeaways

  • An X-ray involves passing a very tiny burst of invisible electromagnetic radiation to a part of your body or your whole body and capturing it on film.
  • An X-ray procedure is non-invasive, very safe, and can be done in a few minutes.
  • The benefits of X-rays greatly outweigh the risks.

What is an X-ray procedure?

An X-ray is a quick diagnostic procedure to see the insides of your body. It is an essential tool used to diagnose many health conditions. It involves passing a very tiny burst of invisible electromagnetic radiation to a part of your body or your whole body and capturing it on film. This article only talks about X-rays used in medical imaging and diagnostics. An X-ray procedure is non-invasive, very safe, and can be done in a few minutes. You do not need to do something or have any preparations before an X-ray. 

An X-ray works on the basis that different areas of the body absorb the rays in varying degrees. When X-rays are passed through your body, your organs block some of it. The remaining X-rays come out of your body and then captured on a photographic film. In an X-ray image, the tissues or organs that let a lot of X-rays pass through will show up dark or even black on the film. Those that absorb a lot of rays such as your bones leave white areas in the film. The film is developed to make X-ray images, which will be studied by the doctor.

Doctors and dentists prescribe X-rays. However, the procedure is usually carried out by professionals called as X-ray technicians or radiographers. Variations of X-ray procedures such as computed tomography (CT), positron emission tomography (PET), mammography, intravenous pyelogram, and bone densitometry (DEXA) are also used to diagnose other health problems.

What exactly are X-rays?

You must learn something about the nature of X-rays to understand the procedure. Despite being called as "X-rays", they are not really that mysterious. An X-ray is a form of radiation. It is a distinct form of visible light, ultraviolet light, gamma rays, and heat. It also means that X-rays occur in nature.

Compared to UV rays and visible light, an X-ray has a lot of energy that can penetrate objects like the human body and makes it able to expose photographic plates. X-rays are invisible to the eye so you cannot see them. However, note that X-rays are an ionizing radiation that can cause harm to the living tissues. Being exposed to X-rays for a long time or receiving a very high dose can result in radiation burns.

X-rays used in clinics only use a low dose at very brief bursts (fractions of a second), and the rays are focused on a specific area of your body, which greatly minimizes exposure.

How are X-rays produced?

X-rays are produced when energized electrons or ions hit a target. In clinics or hospitals, a device called an X-ray tube creates X-rays by bombarding a target made of tungsten or other metals with electrons of high velocity. The fast electrons collide with the atoms of tungsten, causing its atoms to ionize and produce X-rays.

Doctors refer X-ray images as a "roentgenogram" and the science of X-rays as "roentgenology". It is named after its discoverer Wilhelm Roentgen.

Variations or Types of X-ray Procedures

There are several types of X-ray procedures aside from the typical chest X-ray. The following are considered as specialized procedures:

1) CT or CAT scan

"CT" stands for computerized tomography that takes X-ray images from different angles. A CT scan machine looks like a large donut-shaped tube laid horizontally. The opening space is large enough for a person to lie down inside it. To use the machine, the patient is put inside the tube, which houses X-ray machines that actually go around the tube as it captures images throughout a body part. It produces detailed 3D X-ray images, and it is ordered if ordinary X-rays or ultrasound showed abnormal findings. Because it takes several X-ray images, a CT scan gives a higher dose of radiation than ordinary X-rays.

2) Barium X-ray

This type of X-ray uses a chalky element called barium that shows up very clearly in X-rays. It is used to check the insides of your digestive tract, which is normally invisible in usual X-rays. Barium is harmless and not absorbed by the body. You will either have to take barium by mouth (barium swallow) or as an enema (barium enema) and then have an X-ray afterward. Barium sticks to the insides of your upper digestive tract or lower bowels that can show up problems such as ulcers, tumors, or blockages.

3) DEXA scan

A DEXA scan is also called as bone densitometry and stands for "dual-energy X-ray absorptiometry". It is an X-ray procedure measuring the density of your bones. It is used to check for bone thinning or osteoporosis. DEXA scans are quick and non-invasive and sometimes recommended as a screening tool for osteoporosis. Some DEXA scans use ultrasound, which has no radiation, unlike X-rays.

4) Mammography

Mammography makes detailed images of the internal tissues of the breasts using an X-ray. It is used to screen and diagnose breast cysts or cancer. It involves placing a breast between two metal plates, and the X-ray machine sends X-rays through the plates to create an image. Doctors recommend women over 40 to have yearly mammography scans.

5) Angiography

It produces X-ray images of the heart's arteries, which are normally invisible. It involves injecting a dye that absorbs X-rays into an artery, which then travels to the heart and nearby blood vessels. An X-ray procedure is performed, and the blood vessels become delineated by the dye in the film. Angiography is often used to check for blockages in the heart that may cause angina, or determine the risk of atherosclerosis or heart attack.

6) Intravenous pyelogram (IVP)

IVP is used to make an X-ray of the kidneys, urinary bladder, ureters, or the prostate, which are normally invisible in ordinary X-rays. It involves injecting a dye into a vein in the pelvis, so the doctor can check and determine the health and function of the urinary tract.

7) Fluoroscopy

It is an advanced X-ray procedure that produces X-ray images of your organs while they are in motion, like a movie. It involves passing a continuous beam of X-rays on a specific body part, which is captured and sent to a monitor that produces moving images of your organs. It is used to locate foreign bodies or other problems in your organs.

8) Discography

It is a procedure that scans your spine to check for problems such as herniated discs, spine fractures, spinal nerve compression, or degenerative disc disease. It involves injecting a dye into the spine area under anesthesia and then doing a CT scan. This procedure creates very detailed images of your spine.

Preparing for an X-ray Procedure

To take an X-ray image, there must be an X-ray source, shielding, and a large photographic film. Usually, clinics and hospitals house such equipment in a particular room that is typically shielded so radiation will not come out. Before the X-ray procedure, the technician will ask if you are pregnant or possibly pregnant if you are a woman of reproductive age. X-rays can possibly harm the fetus when done to pregnant patients.

There is almost no preparation needed for the procedure, except removing metal or jewelry over the body part to be scanned. Metal have to be removed because it shows up very clearly in X-rays and can ruin the image. If a chest X-ray is needed, it is typical to remove undergarments such as brassieres (due to metal clasps and wire), necklaces, or other jewelry.

Sometimes, you will have to wear an X-ray gown, which has shielding that protects areas not to be scanned. You will be positioned between the X-ray source and the photographic film. The X-ray technician will position the film on the body area to be scanned. If needed, you may have to wear a shielding apron, which will be provided by the technician.

After getting into the position, the X-ray technician will usually ask you to hold your breath and stop moving for a few seconds. At this time, a very brief burst of X-ray is passed on the body part, and then the procedure is over.

Common Uses of X-Rays

1) Diagnosing bone conditions

X-rays are a very important diagnostic tool in medicine. It enables your doctor to know what is going on inside your body quickly. X-rays are most useful in diagnosing bone conditions. The bones show up very clearly in X-ray films, and it can easily show up fractures, injuries, or any abnormalities.

Conditions such as arthritis, bone tumors, or bone spurs will easily show up in X-rays. Some surgical procedures, such as spinal fusion, joint replacement, and fracture reductions need X-rays as a sort of a guide, and to check for proper alignment or stabilization of the affected bones.

2) Identifying foreign bodies

The next most common use of X-rays is detecting foreign bodies inside the body. Swallowed objects such as coins, small toys, or even smuggled or stolen items, show up very clearly in X-ray films. Small children and kids often swallow objects, and X-rays are quick and non-invasive means for detecting swallowed foreign objects. Sometimes, suspected thieves or smugglers are subjected to X-rays to determine if they have swallowed their stolen or smuggled items.

3) ER assessment

X-rays are also commonly prescribed to certain patients in the emergency room. It is quite useful for the assessment of gunshots, vehicular and workplace accidents, or the presence of foreign objects inside the body. Because it is quite indispensable, many emergency rooms are not distant from X-ray rooms. Some may even have their own portable X-ray machines.

4) Dental procedures

Dental X-rays are also commonly used. Dentists find X-rays valuable to visualize teeth, soft tissues, and the bone tissues in the teeth, mouth, and jaw. X-rays are sometimes used to see cavities, hidden dental structures (like the wisdom teeth), cysts, tumors, or abscesses.

5) Diagnosing other health problems

X-rays are used for diagnosing various health problems such as tuberculosis, cancer, as well as problems in the heart, lungs, and digestive tract. Aside from diagnosing diseases, doctors may recommend X-rays to quickly check if you’re really healthy on the inside.

Are X-rays really safe?

If you want to know the safety of X-rays, you should first understand its dosage or effective radiation dose in your body. A radiation dosage is commonly stated in a unit called sievert, which represents the amount of radiation received by your body. Doctors and X-ray technicians are also concerned about the radiation you receive from X-ray procedures, so they will monitor your radiation dose when several X-ray procedures are needed.

Most people are wary of X-rays and are really unfamiliar with the nature and physics of radiation. If you are concerned about radiation, you should note that there is a thing called "natural radiation". We get natural radiation from cosmic rays from space hitting the earth, the presence of natural elements that emit radiation, and exposure to poisonous radon gas. It simply means that we receive doses of radiation on a constant basis.

Having a typical chest X-ray means receiving a dose of 0.1 millisieverts (mSv), which is equivalent to a two-day exposure to natural radiation. Other X-ray procedures have higher doses. For example, a dose of intravenous pyelogram is 3 mSv while an abdominal or pelvic CT scan can give you approximately 10 mSv.

In contrast, you receive 0.03 mSv of radiation in a single airplane flight that lasts for 5 hours and 50 minutes, or 2 mSv a year for living in a place with high levels of radon, or a massive 160 mSv per year for heavily smoking cigarettes.

So that means having X-rays does not put dangerous amounts of radiation into your body. The benefits of X-rays greatly outweigh the risks. Not having an X-ray, if needed, could put your health at risk.

What does a chest X-ray show?

A chest X-ray creates pictures of organs in your chest, including your lungs, heart, and major blood vessels. It is prescribed to diagnose several common health conditions such as tuberculosis, lung cancer, pneumonia, sarcoidosis, scarring, or the presence of foreign objects in the lungs. A chest X-ray can also reveal certain heart problems such as heart enlargement, heart failure, enlargement of the aorta, and congenital heart disease.

What does a normal chest X-ray look like?

A normal chest X-ray will show structures in your chest area. The image of airways are large and of good quality, the lungs are mostly clear (black) and have no noticeable densities. The heart should be normal in size and not visibly enlarged. These features are often not outright noticeable to an untrained eye. Only a doctor can determine whether your chest X-ray result is normal or not.

If there are abnormal findings in your chest X-ray, your doctor may order other tests or diagnose your condition and prescribe treatment.