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
  • Neuroscience Services
  • Head CT Scan
Content

Head CT Scan

A head computed tomography (CT) scan uses many x-rays to create pictures of the head, including the skull, brain, eye sockets, and sinuses.

Alternative Names

Brain CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain

How the Test is Performed

Head CT is done in the hospital or radiology center.

You lie on a narrow table that slides into the center of the CT scanner.

While inside the scanner, the machine's x-ray beam rotates around you.

A computer creates separate images of the body area, called slices. These images can be:

  • Stored
  • Viewed on a monitor
  • Printed on film

Three-dimensional models of the head area can be created by stacking the slices together.

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

A complete scan usually take only 30 seconds to a few minutes.

Open Article Detail

How to Prepare for the Test

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

  • Contrast can be given through a vein (IV) in your hand or forearm. If contrast is used, you may also be asked not to eat or drink anything for 4 to 6 hours before the test.
  • 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 safely receive it.
  • Before receiving the contrast, tell your provider if you take the diabetes medicine metformin (Glucophage). You may need to take extra precautions. Also let your provider know if you have any kidney function problems as the IV contrast can worsen this problem.

If you weigh more than 300 pounds (135 kg), find out if the CT machine has a weight limit. Some machines do.

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

How the Test will Feel

The x-rays produced by the CT scan are painless. Some people may have discomfort from lying on the hard table.

Contrast material given through a vein may cause a:

  • Slight burning feeling
  • Metallic taste in the mouth
  • Warm flushing of the body

This is normal and usually goes away within a few seconds.

Why the Test is Performed

A head CT scan is recommended to help diagnose or monitor the following conditions:

  • Birth (congenital) defect of the head or brain
  • Brain infection
  • Brain tumor
  • Buildup of fluid inside the skull (hydrocephalus)
  • Injury (trauma) to the brain, head, or face
  • Stroke or bleeding in the brain

It may also be done to look for the cause of:

  • Abnormal head size in children
  • Changes in thinking or behavior
  • Fainting
  • Headache, when you have certain other signs or symptoms
  • Hearing loss (in some people)
  • Symptoms of damage to part of the brain, such as vision problems, muscle weakness, numbness and tingling, hearing loss, speaking difficulties, or swallowing problems

What Abnormal Results Mean

Abnormal results may be due to:

  • Abnormal blood vessels (arteriovenous malformation)
  • Bulging blood vessel in the brain (aneurysm)
  • Bleeding (for example, subdural hematoma or bleeding in the brain tissue)
  • Bone infection
  • Brain abscess or infection
  • Brain damage due to injury
  • Brain tissue swelling or injury
  • Brain tumor or other growth (mass)
  • Loss of brain tissue (cerebral atrophy)
  • Fluid collecting inside the skull (hydrocephalus)
  • Problems with the hearing nerve
  • Stroke or transient ischemic attack (TIA)

Risks

Risks of CT scans include:

  • Being exposed to radiation
  • Allergic reaction to contrast dye
  • Kidney damage from the contrast dye

CT scans use 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 provider should weigh this risk against the benefits of getting a correct diagnosis for a medical problem.

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 a person with an iodine allergy is given this type of contrast, nausea or vomiting, sneezing, itching, or hives may occur.
  • If you absolutely must be given such contrast, your provider may give you antihistamines (such as Benadryl) or steroids before the test to prevent an allergic reaction.
  • The kidneys help remove iodine from the body. Those with kidney disease or diabetes may need to receive extra fluids after the test to help flush the iodine out of the body.

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

Considerations

A CT scan can reduce or avoid the need for invasive procedures to diagnose problems in the skull. This is one of the safest ways to study the head and neck.

Other tests that may be done instead of a head CT scan include:

  • MRI of the head
  • Positron emission tomography (PET) scan of the head

References

Chernecky CC, Berger BJ. C. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:266-432.

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

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

          Vintner Honors Late Wife With Gift to CPMC's Forbes Norris Center

          Vintner pledges to gift 100 percent of the profits, in perpetuity, from a vineyard named after and planted by his wife Susan before her onset of ALS

          TeleStroke Technology – Stroke Care Close to Home

          Judy Hall describes how the telestroke program at CPMC helped save her life, while delivering high-quality, personalized care.

          Taking Back Childhood From Epilepsy

          The team at Sutter Medical Center, Sacramento helped Sammy take control of his epilepsy.

          Local Artist Paints Again After Gamma Knife Radiosurgery

          Fred Ekman is grateful for the specialized neurological care that allowed him to return to painting, teaching and an active lifestyle.

          Severe Migraines Lead to Discovery of Brain Tumor

          A migraine sufferer, Tracey had learned to cope with frequent, severe headaches. But one day unbearable pain led to the discovery of a brain tumor.

          Taking Control of Her Epilepsy – Janel’s Story

          The team at California Pacific Medical Center helped Janel take control of her epilepsy.

          View All Stories

          Related Videos

          Sutter Stroke Network

          Sutter Stroke Network

          Sutter Stroke Network

          Sutter Stroke Network
          Through telemedicine technology, stroke specialists in the Sutter Health network provicde video conferencing in communities outside of San Francisco bringing top-notch stroke care to community hospitals.

          Stroke Telemedicine at Sutter

          Through telemedicine technology, stroke specialists in the Sutter Health network provicde video conferencing in communities outside of San Francisco bringing top-notch stroke care to community hospitals.

          Stroke Telemedicine at Sutter
          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 continuing to use the site, you agree to the use of cookies. Privacy Policy Cookie Preferences

          Privacy Policy Cookie Preferences