Imaging technology allows doctors and their staff to get a better picture of what’s happening inside the body. This means significant improvement in care and the ability to detect and identify illnesses that previously might have gone undetected.
Your doctor may recommend one of several imaging scans to help provide more information about your health. Here’s how you can prepare and what you can expect.
A CT scan, or computerized tomography scan, combines a series of X-ray images taken from several angles, using computer processing to create images from inside the body. They are able to provide more detailed images than a standard X-ray.
Preparation for a CT scan may depend on which part of the body is being scanned. You might be asked to remove clothing and wear a hospital gown, and you may also be told to remove any metal on your person, such as a belt, jewelry, dentures or eyeglasses. In addition, you may be told to refrain from eating or drinking for several hours before the scan.
For some CT scans, a dye called contrast material is needed to help highlight a particular area inside the body. Contrast material can be given in three ways:
- • Orally: For cases where the esophagus or stomach is being scanned
- • Via injection: Through a vein in the arm, contrast material is given via injection for exams of the gallbladder, urinary tract, liver or blood vessels
- • Via enema: For help with visualizing the intestines, contrast material may be inserted in your rectum
If you have a young child or infant that needs a CT scan, preparation might include a sedative to keep them calm. Too much movement during the scan can blur the images produced and lead to incorrect results, so children who can’t sit still on their own may need extra help.
Magnetic resonance imaging (MRI) is an imaging technique that uses a magnetic field and radio waves to produce images of organs and tissues inside the body. An MRI machine can produce 3D images that can be viewed from multiple angles.
Preparation for an MRI is relatively simple. You will not have to change your eating habits or any medications before the procedure unless your doctor instructs you otherwise. You’ll be asked to remove clothing and change into a medical gown, and to ensure that the test isn’t affected by them, you’ll be asked to remove the following items before the test:
- • Jewelry
- • Hairpins
- • Eyeglasses
- • Watches
- • Wigs
- • Dentures
- • Hearing aids
- • Underwire bras
A PET scan, or positron emission tomography scan, is a test that helps indicate the functionality of tissues and organs. It uses a radioactive tracer that’s injected, swallowed or inhaled, and can help detect disease or conditions that might take longer to show up on other imaging tests.
Before your PET scan, you may be told to avoid strenuous exercise for a couple days and stop eating a few hours beforehand. Things to tell your doctor before a PET scan include:
- • If you’ve ever had a bad allergic reaction
- • If you’ve been sick recently or have a medical condition like diabetes
- • If you’re taking any medications, vitamins or herbal supplements
- • If you’re pregnant or think you might be pregnant
- • If you’re breastfeeding
- • If you’re claustrophobic (afraid of enclosed spaces)
Your doctor may give you additional instructions depending on your individual case.
If you’re preparing for an imaging scan of any kind, your doctor can offer more specific guidelines. You can also use radiologyinfo.org as a resource to help you prepare.
“CT scan (How you prepare).” The Mayo Clinic. http://www.mayoclinic.org/tests-procedures/ct-scan/basics/how-you-prepare/prc-20014610
“Positron emission tomography scan (How you prepare).” The Mayo Clinic. http://www.mayoclinic.org/tests-procedures/pet-scan/details/how-you-prepare/ppc-20319717
“MRI (How you prepare).” The Mayo Clinic. http://www.mayoclinic.org/tests-procedures/mri/details/how-you-prepare/ppc-20235719