X-rays, CT Scans, and MRIs: What exactly are they?

When it comes to diagnosing an illness or injury, few things have done as much for the practice as imaging machines. Medical technology now allows doctors to accurately see, assess, and repair an injury with very little guess work. Diagnostic imaging can help to narrow the causes of an injury or pain and ensure that the diagnosis is accurate. These scanning techniques—X-rays, computed tomography (CT) scans, magnetic resonance imaging (MRI)—are often mentioned in articles, in doctors’ offices, and with your lawyer, but what exactly are they and how are they different?

These imaging tools allow a doctor “see” inside your body in order to get a more accurate idea of what is physically going on behind the skin. Through complicated advances in technology, these scans can distinguish between bones, muscles, ligaments, cartilage, organ tissue, and skin. By having an image of the actual bones (or whatever is being scanned) doctors can pinpoint an exact location of where the issue lies.

For people who have been injured in a car accident or slip-and-fall, having concrete proof of their injury can be all the difference in proving their personal injury case. For others, the scans may find the exact location of an injury that has been causing them pain for years. From back injuries to brain trauma, scanning has made it possible to diagnosis even the most subtle of maladies.

What is an X-ray?

The term X-ray actually refers to the type of radiation used to create what is more accurately called, a radiograph. The X-ray was discovered by German physicist Wilhelm Roentgen in 1895. He called it X-radiation because he didn’t know exactly what it was; so he used the letter “X” as a placeholder for a future name that never came.

X-rays are the most commonly available and widely used diagnostic imaging technique. This is because the equipment is less expensive and the images are cheaper to produce.

Chances are, if you are injured, an X-ray will be part of your initial diagnosis—even if more complicated scans are needed later.

An X-ray works by placing the part of the body to be imaged between the x-ray machine and a special photographic film. The process then works similar to a photograph, where light reacts to the film and creates an image. Except in X-rays, minor radiation is what reacts with the film.

As the electromagnetic waves move through your body, they are blocked by more solid things like bone; some radiation can move through more dense stuff, like a muscle, and almost all the radiation can move through softer materials like skin. The more radiation that is blocked, the more white it shows up on the film. This is how the gray-scale image is produced.

Since cracks in bones would obviously allow radiation to pass through, they show up crystal clear on X-rays. Likewise, abnormalities in organ tissue, like a herniated disc, show up well as well. Sometimes, to make certain softer tissues—like organs—standout, patients are given a dye solution, most commonly, barium sulfate. This dye allows for more absorption of the radiation, creating a clearer image.

Radiation exposure, in general, is harmful to the human body, but X-rays produce so little, for such a short amount of time, that it has little effect. It should be noted that x-rays are considered carcinogenic by the World Health Organization (However, the benefits of X-ray technology far outweigh the potential negative consequences of using them.)

Besides being relatively inexpensive, taking X-rays and developing the images is a relatively short process. For this reason, they are a popular choice for patients. For those situations where more powerful techniques are needed, there are other types of scans. As far as X-rays go, there are three common types: radiography, fluoroscopy, and computed tomography.

Radiography is the most common type of X-ray imaging. It is often used to image broken bones, teeth (like at the dentists), and the chest for lung issues. Radiography also uses the smallest amount of radiation.

Fluoroscopy is similar to a standard X-ray, except it can be viewed in real-time, creating a moving image of the X-ray. This allows doctors to see stuff moving through the digestive tract or how joints move, for example. Fluoroscopy uses more radiation than a standard X-ray, but the amounts are still minuscule.

Computed (Axial) Tomography [CT scan or CAT scan]

Computed axial tomography is more often shortened to CAT scan or CT scan. This imaging tool combines X-ray scanning technology with sophisticated computer software to produce a more detailed image of the human body. A CT scan allows a physician to see a more accurate image of the size, shape, and position of structures inside the body, such as organs, tissues, or tumors.

The general advantage of CT scan is that it produces 360 degrees of images, allowing the doctor (or an attorney or expert witness) to find the best image that most accurately portrays the injury.

CT scans are also more capable of imaging multiple structures (like bone, soft tissue, and blood vessels) simultaneously. This is another benefit of taking so many images at once.

Like the MRI (which is covered below) CT scans require patients to enter a tube-like structure. However, the tubes used for CTs are much more open, which seldom creates anxiety or claustrophobia. It is also a much quicker procedure than MRIs. In order to capture a CT scan, the patient must lay motionless as a sliding table enters the cylinder-like CT scanner. Then, the X-ray machine slowly rotates around the patient, taking many pictures from all directions. This can range from 4 slices to 640 slices. This is referred to as “multi-slice” or “multi-detector” technology and may be abbreviated as MSCT or MDCT. The image slices are often less than 1 millimeter thick. Computer software then combines the images to produce a view of the inner body. The images may also be viewed one at a time.

CT scanning is optimal for:

  • Imaging multiple bodily systems at the same time
  • Pinpointing injuries in bones
  • Diagnosing lung and chest issues
  • Detecting cancers
  • Imaging patients who cannot have an MRI (see below)

CT scans are common to analyze the bony structure, but they are used to diagnosis severe trauma to the brain, spinal cord, and neck, chest, abdomen, or pelvis. As with a regular X-ray, barium may be used to produce a more contrasted image.

It is worth noting that a CT scan can cost much more than a regular X-ray. For this reason, they are only used when a more detailed image is necessary.

Magnetic Resonance Imaging (MRI)

Magnetic resonance imaging (MRI) combines a powerful magnetic field and radio waves with advanced computer software to produce accurate, detailed pictures of different internal body structures. MRIs produce a more contrasted image between normal and abnormal tissue structures than a CT scan.

Unlike different forms of X-rays, there is no radiation exposure with MRIs. However, an MRI is similar to a CT in that it produces a cross-sectional view of the body. Because magnets are used, patients with metal supports, certain implants, and some kinds of body modification cannot have an MRI performed.

An MRI machine is primarily made up of two large magnets. It works by using a computer to record the rate at which the different structures in your body (tendons, ligaments, nerves, muscles, bone, brain tissue, etc.) vibrate. This data is then translated into a detailed image of the inner body.

The human body is largely made of water, which is comprised of hydrogen and oxygen atoms. At the center of every atom is a small particle called a proton, which has a magnetic charge and is thus sensitive to a magnetic field. The MRI magnets then rapidly pulse on and off, causing the atoms to microscopically vibrate (or resonate, as the name implies). The scanner then detects these minor movements—they are different depending on what the material is made of. A computer then uses this data to create a detailed cross-sectional image.

MRI scanners are great for detecting:

  • Abnormalities or injuries in the brain and spinal cord.
  • Growths and other abnormalities like tumors and cysts.
  • Certain types of heart problems.
  • Injuries or irregularities in the joints, vertebrae, etc.
  • Diseases of the organs.

MRIs are especially great for more detailed imaging diagnostics, which an X-ray just cannot see. For example, MRIs can detect:

Brain tumors, traumatic brain injuries, developmental issues, multiple sclerosis, stroke, dementia, infection, concussions, and the causes of headaches.

Issues with arteries and veins in order to pinpoint aneurysms, blood clots, and artery diseases.

Irregularities in cartilage and bone structure caused by injury, disease, or aging. It can detect herniated discs, pinched nerves, spinal tumors, spinal cord compression, and spinal fractures.

MRIs typically take 30 to 90 minutes. Like the CT scanner, the process requires a patient to lay motionless on a table that slides into the tube-shaped MRI scanner. The machine is also quite noisy. This combination of time, lying motionless in a tube, and the noise level can cause some patients to feel anxiety or claustrophobia while being scanned. For this reason, MRIs can be limiting. However, if a patient can stick with it, the results are nearly unmatched.

For more detailed information on the different types of scans used to specifically image the brain, check out this article.

Dolman Law Group

The Dolman Law Group is a firm of personal injury attorneys working in the New Port Richey area. We are serious about getting victims of negligent injuries the compensation they deserve. We are also serious about providing our clients—and the community at-large—which as much information as possible about varying injury subjects. The more educated a client is, the more power they have to take control of their recovery. For this reason, we are dedicated to continually providing information to our clients through our daily article postings. We hope you find this information valuable.

If you or a loved one has been injured due to someone else’s negligence, do not hesitate to give us a call. We offer a free, no-pressure consultation to help you understand your case and to recognize your options. If you think you need our help, contact us today by calling (727) 853-6275 or by using our contact page. We look forward to hearing from you.

Dolman Law Group
5435 Main Street
New Port Richey, FL 34652
(727) 853-6275