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CT Scans

CT - Computed Tomography

A CT (computed tomography) scan is a type of x-ray that creates two- and three-dimensional images of the body. Unlike traditional x-ray, a CT scanner can take "slices" of the body that lets the doctor look at certain areas very closely.

A few examples of CT scans are:

  • Chest CT - to look at the heart, lungs, and other parts of the cardiopulmonary system
  • Head and neck CT - to see the brain, spinal cord and nervous system
  • Virtual Colonoscopy - to look at the gastrointestinal tract
  • CTA (computerized tomographic angiography) - uses a type of dye to examine blood vessels and seek out blockages, internal bleeding, and other aspects of blood flow
  • Abdominal/ Pelvic CT - looks at the kidneys, liver, reproductive organs, and other abdominal areas
  • Musculoskeletal CT - looks at the muscles and the bones

What is it like to have a CT scan?
A technologist will help you lay down on a table. The table then slides into a doughnut-shaped machine. X-rays are taken and sent to a computer. These images can be used to find tumors, nodules, cysts, and other abnormalities.

The exam itself may take from seconds to several minutes, but setup time can take up to 30 minutes. While the test is going on, the technologist may ask you to stay still or hold your breath for short periods. For some tests, you will need to have an IV or swallow a "contrast agent" that will help the doctors see the area better.

The technologist will be watching the images on a TV monitor outside the room. If you have any questions, you can ask the technologist.

How do I prepare for a CT scan?
Unless your doctor tells you to do something else, you'll keep taking your medications and eating normally. For CT scans of the abdomen, you may have to drink a contrast solution in order to prepare for the exam.

The contrast agents used in CT scans often contain iodine. If you have an allergy to iodine or shellfish, or if you have impaired kidney function, you should talk with your doctor before having a contrast agent.

If you are pregnant or may be pregnant, you should check with your doctor before having a CT scan. If you are a diabetic who uses Glucophage, check with your doctor before you have a CT scan, as Glucophage must be stopped 48 hours after the exam.

For additional information about your test please visit the RadiologyInfo website.


Referral information for physicians

You can make a referral for your patients by calling 617-665-1298. ALL sites have staff that perform Head CT's 24/7 for stroke patients.