Jump to content

Choose locationChoose Location
  • Sign in or Enroll
    • Open I want to choose my medical group or hospital
    • Clear my location
Change Location

We've expanded your view

You are now viewing all services in the Sutter Health network. You can change your location above to narrow your view to a medical group, hospital, city or zip.
Sutter Health
  • Video Visits
  • Find Doctors
  • Find Locations
  • Treatments & Services
  • Locations
  • Sign in or Enroll
    • Video Visits
    • Find Doctors
    • Find Locations
    • Treatments & Services
    • COVID-19 Resources
    • Pay a Bill
    • Symptom Checker
    • Get Care Today
    • Diseases & Conditions
    • Health & Wellness
    • Classes & Events
    • Research & Clinical Trials
    • For Patients
    • About Sutter Health
    • Giving
    • Volunteering
    • Careers
    • News
    • For Medical Professionals
    • Other Business Services
Close Search
  • Home
  • Services
  • Imaging Services
  • CT Scan
Content

CT Scan

A computed tomography (CT) scan is an imaging method that uses x-rays to create pictures of cross-sections of the body.

Related tests include:

  • Abdominal and pelvis CT scan
  • Cranial or head CT scan
  • Cervical, thoracic, and lumbosacral spine CT scan
  • Orbit CT scan
  • Chest CT scan

Alternative Names

CAT scan; Computed axial tomography scan; Computed tomography scan

How the Test is Performed

You will be asked to lie on a narrow table that slides into the center of the CT scanner.

Once you are inside the scanner, the machine's x-ray beam rotates around you. Modern spiral scanners can perform the exam without stopping.

A computer creates separate images of the body area, called slices. These images can be stored, viewed on a monitor, or printed on film. Three-dimensional models of the body area can be created by stacking the slices together.

You must stay still during the exam, because movement causes blurred images. You may be told to hold your breath for short periods of time.

Complete scans most often take only a few minutes. The newest scanners can image your entire body in less than 30 seconds.

Open Article Detail

How to Prepare for the Test

Certain exams require a special dye, called contrast, to be delivered into your body before the test starts. Contrast helps certain areas show up better on the x-rays.

Let your health care provider know if you have ever had a reaction to contrast. You may need to take medicines before the test in order to avoid another reaction.

Contrast can be given several ways, depending on the type of CT being performed.

  • It may be delivered through a vein (IV) in your hand or forearm.
  • You might drink the contrast before your scan. When you drink the contrast depends on the type of exam being done. The contrast liquid may taste chalky, although some are flavored. The contrast passes out of your body through your stools.
  • Rarely, the contrast may be given into your rectum using an enema.

If contrast is used, you may also be asked not to eat or drink anything for 4 to 6 hours before the test.

Before receiving IV contrast, tell your health care provider if you take the diabetes medication metformin (Glucophage). People taking this medicine may need to stop temporarily. Also let your provider know if you have any problems with your kidneys. The IV contrast can worsen kidney function.

Find out if the CT machine has a weight limit if you weigh more than 300 pounds (135 kilograms). Too much weight can damage the scanner.

You will need to remove jewelry and wear a hospital gown during the study.

How the Test will Feel

Some people may have discomfort from lying on the hard table.

Contrast given through an IV may cause a slight burning feeling, a metallic taste in the mouth, and a warm flushing of the body. These sensations are normal and usually go away within a few seconds.

Why the Test is Performed

A CT scan creates detailed pictures of the body, including the brain, chest, spine, and abdomen. The test may be used to:

  • Diagnose an infection
  • Guide a surgeon to the right area during a biopsy
  • Identify masses and tumors, including cancer
  • Study blood vessels

Normal Results

Results are considered normal if the organs and structures being examined are normal in appearance.

What Abnormal Results Mean

Abnormal results depend on the part of the body being studied. Talk to your provider about questions and concerns.

Risks

Risks of CT scans include:

  • Allergic reaction to the contrast dye
  • Damage to kidney function from the contrast dye
  • Exposure to radiation

CT scans expose you to more radiation than regular x-rays. Having many x-rays or CT scans over time may increase your risk for cancer. However, the risk from any one scan is small. You and your doctor should weigh this risk against the value of the information that will come from a CT scan. Most new CT scan machines have the ability to reduce the radiation dose.

Some people have allergies to contrast dye. Let your provider know if you have ever had an allergic reaction to injected contrast dye.

  • The most common type of contrast given into a vein contains iodine. If you have an iodine allergy, a type of contrast may cause nausea or vomiting, sneezing, itching, or hives.
  • If you absolutely must be given such contrast, your doctor may give you antihistamines (such as Benadryl) or steroids before the test.
  • Your kidneys help remove iodine from the body. You may need to receive extra fluids after the test to help flush iodine out of your body if you have diabetes or kidney disease.

Rarely, the dye may cause a life-threatening allergic response called anaphylaxis. If you have any trouble breathing during the test, tell the scanner operator immediately. Scanners come with an intercom and speakers, so the operator can hear you at all times.

References

Blankensteijn JD, Kool LJS. Computed tomography. In: Cronenwett JL, Johnston KW, eds. Rutherford's Vascular Surgery. 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 22.

Shaw AS, Prokop M. Computed tomography. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging. 6th ed. New York, NY: Elsevier; 2015:chap 4.

Wahl RL. Imaging. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff's Clinical Oncology. 5th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 18.

Related Articles

From Sutter Health

    Talking To Your MD

      Self Care

        Other Related Content

          Patient Information

          Couple in kitchen looking at digital tablet

          Interested in becoming a Sutter patient? Here’s what you need to know about health plans, choosing a doctor and how to get started today.

          • Accepted Health Plans
          • Tips for Choosing a Doctor
          • Health Insurance Guide

          Find a Doctor Who Fits Your Needs

          Patient Stories

          After Second Heart Attack, Man Gets Heart Transplant

          At age 50 Nick had a second heart attack. The heart damage was so extensive, there was only one promising solution: a heart transplant.

          Woman Able to Conceive Twins after Robotic Surgery

          Having uterine fibroids removed through robotic surgery at PAMF allowed Gwen to have "miracle" babies.

          Sutter’s Integrated Network Provided Advanced Care – Fast

          From the moment Patricia collapsed from a stroke, doctors began coordinating her transfer from Novato to the CPMC specialty stroke center.

          Emergency Gallbladder Surgery Funded By Charity Care

          Emergency gallbladder surgery, paid for by Sutter Health's Charity Care program, saved Oakland resident Jose Dueñas' life.

          Emergency Heart Surgery Saves Woman's Life

          When Elizabeth Hobbie's heart stopped, her doctors sprang into action — ultimately saving her life.

          Friendship and Philanthropy

          Denny LeVett and his wife Jeanne decided it was time to make another major gift to PAMF, in honor of Duncan Matteson, as well as their friendship.

          View All Stories

          Related Videos

          In this video (2 of 4 in the series), Chef Terese Esperas of the Sacramento Natural Foods Co-op prepares a delicious Orange Pistachio Quinoa.

          Cancer-fighting recipes: Orange Pistachio Quinoa

          In this video (2 of 4 in the series), Chef Terese Esperas of the Sacramento Natural Foods Co-op prepares a delicious Orange Pistachio Quinoa.

          Cancer-fighting recipes: Orange Pistachio Quinoa
          Atrial Fibrillation Explained by Steven Hao, MD, Electrophysiologist at CPMC

          Atrial Fibrillation Explained by Steven Hao, MD

          Atrial Fibrillation Explained by Steven Hao, MD, Electrophysiologist at CPMC

          Atrial Fibrillation Explained by Steven Hao, MD
          Sachin Shah, MD, FACS, Director of Robotic & Minimally Invasive Cardiac Surgery at Sutter Health CPMC and Palo Alto Medical Foundation discusses the benefits of robotic mitral valve repair.

          Benefits of Robotic Mitral Valve Repair

          Sachin Shah, MD, FACS, Director of Robotic & Minimally Invasive Cardiac Surgery at Sutter Health CPMC and Palo Alto Medical Foundation discusses the benefits of robotic mitral valve repair.

          Benefits of Robotic Mitral Valve Repair
          Chef Terese Esperas of the Sacramento Natural Foods Co-op provides a cooking demonstration with nutritious cancer-fighting recipes this four-part series.

          Cancer-fighting recipes: Gazpacho

          Chef Terese Esperas of the Sacramento Natural Foods Co-op provides a cooking demonstration with nutritious cancer-fighting recipes this four-part series.

          Cancer-fighting recipes: Gazpacho
          Recommended therapeutic exercise for hip surgery patients

          Exercise after Hip Surgery

          Recommended therapeutic exercise for hip surgery patients

          Exercise after Hip Surgery
          CPMC surgeon, Dr Callander explains new options for knee replacement surgery.

          Peter Callander, MD on Custom Knee Replacement Surgery

          CPMC surgeon, Dr Callander explains new options for knee replacement surgery.

          Peter Callander, MD on Custom Knee Replacement Surgery
          Orthopedic surgeon Peter Callander, M.D., talks about why he likes working at NCH.

          Sutter Novato Community Hospital Bone & Joint Care

          Orthopedic surgeon Peter Callander, M.D., talks about why he likes working at NCH.

          Sutter Novato Community Hospital Bone & Joint Care
          In this video (4 of 4 in the series), Chef Terese Esperas of the Sacramento Natural Foods Co-op prepares a flavorful Sautéed Chard with Orange dish.

          Cancer-fighting recipes: Sauteed Chard

          In this video (4 of 4 in the series), Chef Terese Esperas of the Sacramento Natural Foods Co-op prepares a flavorful Sautéed Chard with Orange dish.

          Cancer-fighting recipes: Sauteed Chard
          Recommendations for walking after joint replacement procedures.

          Walking After Joint Replacement

          Recommendations for walking after joint replacement procedures.

          Walking After Joint Replacement

          Doctor Profiles

          The following doctors are part of the Sutter Health network. Learn about the doctors on this site.
          David S. Marcus, M.D.

          David S. Marcus, M.D.

          • Radiology

          Jennifer J. Wan, M.D.

          Jennifer J. Wan, M.D.

          • Radiology

          View All Related Doctors

          The Sutter Health Network of Care
          Expertise to fit your needs
          Primary Care

          Check-ups, screenings and sick visits for adults and children.

          Specialty Care

          Expertise and advanced technologies in all areas of medicine.

          Emergency Care

          For serious accidents, injuries and conditions that require immediate medical care.

          Urgent Care

          After-hours, weekend and holiday services.

          Walk-In Care

          Convenient walk-in care clinics for your non-urgent health needs.

          About Sutter

        • About Our Network
        • Annual Report
        • Awards
        • Community Benefit
        • Contact Us
        • News
        • Giving
        • Find Care

        • Birth Centers
        • Care Centers
        • Emergency Rooms
        • Hospitals
        • Imaging
        • Labs
        • Surgery Centers
        • Urgent Care
        • Walk-In Care
        • View All >
        • Featured Services

        • Behavioral Health
        • Cancer Services
        • Family Medicine
        • Home Health and Hospice
        • Orthopedics
        • Pediatrics
        • Pregnancy
        • Primary Care
        • Women's Health
        • View All >
        • Patient Resources

        • Accepted Health Plans
        • Classes and Events
        • Estimate Costs
        • Flu Resources
        • Health and Wellness
        • Medical Records
        • Medicare
        • My Health Online
        • Pay a Bill
        • Symptom Checker
        • Our Team

        • For Employees
        • Physician Careers
        • Recruiting Events
        • Sutter Careers
        • Vendors
        • Volunteers
          • ADA Accessibility
          • Contact
          • Privacy
          • Do Not Sell My Personal Information

          • LinkedIn Opens new window
          • YouTube Opens new window
          • Facebook Opens new window
          • Twitter Opens new window
          • Glassdoor Opens new window
          • Instagram Opens new window

          Copyright © 2021 Sutter Health. All rights reserved. Sutter Health is a registered trademark of Sutter Health ®, Reg. U.S. Patent & Trademark office.

          Cookie Policy

          We use cookies to give you the best possible user experience. By clicking on "Accept Cookies", closing this pop-up banner or by continuing to use the site, you agree to the use of cookies. Privacy Policy   Cookie Preferences