Computed Tomography


What is CT? Computed Tomography (CT), commonly called CT or CAT scan, is the process of using x-rays to make an image of the body. Is CT safe? Although CT uses X-rays, you do not need to be concerned. All modern methods are used to minimize the amount of radiation during scanning while providing the benefit of a more accurate diagnosis.

If you are pregnant, or think you might be, be sure to tell your doctor so the best decisions can be made regarding your care.

If you have history of an allergy to iodine, shellfish, or x-ray dye, please inform your doctor before you have your CT examination.

Let your CT technologist know before the examination begins if you have not discussed your chance of pregnancy or allergies with your physician.

How to prepare for a CT examination: If your examination requires the use of a contrast agent (a liquid "dye" injected into the vein) you should not eat anything for 4 hours before the examination. Clear liquids are okay to have before your appointment. You will be notified at the time of scheduling if you need to fast. Usual medication can be taken unless noted by your physician. For your examination, you may be asked to wear a gown and remove any items that may interfere with the examination. Your examination may require you to drink an oral contrast agent to opacity the bowel. You will be given this after you check-in for your appointment. Expect this portion to take 45 minutes-1 hour to complete.

What happens during a CT examination?

  • If contrast media will be used, the technologist will start a small IV. You may feel a warm sensation as the contrast is injected; this will last a few minutes.
  • You will be positioned on the CT table so that the area of your body being studied can be best imaged as it moves through the scanner (a large donut-like machine).
  • The examination itself usually takes ten minutes.
  • While the technologist is in the next room operating the machine, the patient is in constant view and within hearing distance.
  • After the examination, the images will be reviewed to ensure that the desired information has been obtained.
  • In some instances, additional images may be required.

After the CT examination: You can resume normal activities unless otherwise advised by your doctor. Following examinations using contrast media, it is best to drink plenty of fluids to help eliminate the contrast from your body. If you are taking certain diabetic medications, you will receive proper instructions immediately after your CT scan to stop such meds, however, do not hesitate to call your physician if you have further questions or do not hear back from him/her regarding resuming your medication.

How will I know the results? The radiologist is a physician who specializes in reading x-rays and will interpret the images from your examination and a report will be typed, approved, and forwarded to your physician. Please give this process 3-5 working days to arrive in your physician's office. If you have any questions, you may call the Radiology Department directly at 503-399-2484.

Patient Preparation

  • Preparation must be completed properly or exam will be rescheduled to the next available appointment
  • Clear liquids only 4 hours before the examination. No solid food. You may take your normal medications.
  • No prep necessary.
  • Upon arrival you will be drinking contrast for certain exams, each wait time is radiologist specific, please be prepared to wait 25-60 minutes before your table time.

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