What Patients Should Know About CT Scans and MRIs
As patients, we normally rely on our doctors to tell us which tests and medications to take for the betterment of our health. Rarely do we question them since they know a whole lot more than most of us when it comes to medical ailments and overall health. However, that doesn’t mean you can’t find out more about the various suggestions doctors make.
If you have an ailment in the body and your doctor finds it hard to determine exactly what it is, they will likely ask you to get either a CT scan or MRI done. The tests are used to provide a detailed view of your internal body to help determine the ailment. We breakdown the two for your better understanding:
CT Scans
CT scans provide imaging using x-rays at different angles. This scan is more in-depth as compared to an x-ray. X-ray tests use a beam of radiation from a set angle and display the image. Since a CT scan uses a series of radiation beams at different angles, it slices the same image up, giving a 3D view so doctors can understand the ailment better. With the help of a computer, an image is produced. CT scans can help determine ailments such as cancer, bone injuries, and chest and lung ailments.
MRI
Magnetic resonance imaging (MRI) uses a magnetic field instead of radiation and provides a more detailed image of the body which also includes soft tissues along with the internal body. It is used to help diagnose the following:
- Brain injury
- Cancer
- Damaged blood vessels
- Spinal cord injury
- Stroke
- Multiple sclerosis
- Bone infections
- Damaged joints
- It can also be used to ensure that various organs are healthy.
Both methods are noninvasive and rely on heavy technology. But when it comes to CT scans, more and more hospitals are opting for mobile CT scanners, which make it easier for them to manage.
Getting Ready for the Test
Preparing for CT Scan and MRI is slightly different. With CT scans, your doctor may recommend you take a contest dye. The dye helps highlight the scanned region more and is generally consumed when scanning the abdomen. It is important to notify your doctor if you have any allergies because you may react to the dye. If you’ve previously had reactions to prednisone (a steroid), iodine, or seafood then the doctor should be immediately notified. Other than that, the doctor may ask you not to drink or eat several hours before the test.
For an MRI, the one thing you need to make sure is that you are not wearing anything that can be detected by magnets. This means, no jewelry, watches, hearing aids, glasses, and other items that may have a metal can be worn during the test. In some cases, a gadolinium dye may be recommended which is injected into the hand or arm. The dye highlights certain details in the imaging and rarely results in any type of reaction. The test can be lengthy for some as it takes anywhere from 30-45 minutes, so if you are claustrophobic, you may want to discuss that with your doctor since you are required to stay in a closed space for that period.
The Test
- CT Scan: You will be asked to put on a robe and remove jewelry and other metal objects so they don’t have any impact on the image produced. The scanner itself is a doughnut-shaped machine and you lie on a flat table in the middle. The table starts to move back and forth and x-ray tubes fitted into the scanner send out beams and different angles. They pass through your body to the other end of the scanner. The test is painless but make sure you are comfortable because you will be asked to stay still as the scan is going on.
- MRI: The MRI machine is a long narrow tube that is open at both ends. Like in a CT scan, you lie down on a flat movable table that slides into the tube. As you slide in, the table stops at the specific part of the body being examined and a magnetic field is created and radio waves are directed to the body. The machine does make tapping and thumping noises, so the technician will likely offer earplugs to block it out.
Understanding the Test Result
After getting either a CT scan or MRI done, you will need to consult your doctor. Unless you are a trained doctor, the images will make little to no sense to you. You will need to consult a radiologist that can explain the results to you. In case of an ailment, they will usually recommend you consult a specialist, depending on the ailment, that can assist you further.
As a patient, it is important for you to understand the tests and treatment doctors recommend. Most of the time, you can consult your doctor and they will be more than willing to give you the information you need. Knowing makes it easier for you to undergo the tests and treatments with a little more ease.

Scott has been working in the radiology field for over 30 years. He finds the biological phenomenons found in humankind fascinating and appreciates the incredible use that diagnostic imagery has to save lives. Other than acting as the President for Catalina Imaging, Scott enjoys spreading the word on new insights and breakthroughs in the radiology field, specifically the impact that mobile imaging has for patient care.