Definition

Computed tomography (CT) is an x-ray scan that utilizes a computer to produce cross-sectional images of the body.

Parts of the Body Involved 

A CT scan can evaluate any part of the body.  Neuroradiology deals primarily with CT scans of the head, sinuses, temporal bone, neck and spine.

Reasons for the Procedure

A CT scan is done to study the skull, brain, jaw, sinuses, facial bones, ear and spine for signs of injuries, tumors or other disease. 

 Your doctor may recommend a CT if you have any of the following symptoms:

• Headache
• Seizures
• Injury to the head, face or eyes
• Dizziness or problems with balance
• Pain
• Confusion
• Behavior or personality change
• Chronic nasal congestion
• Cough
• Swelling in the face, head or neck
• Follow up to back surgery
   

Many conditions and diseases can be diagnosed with a CT.  These include:

• Brain tumor
• Spread of cancer from another location (metastases)
• Cysts
• Congenital brain malformation
• Bleeding
• Strokes
• Aneurysm
• Swelling due to concussion or other trauma
• Swelling due to infection
• Sinus disease
• Fractures of the skull, jaw or facial bone
• Hydrocephalus (excessive accumulation of cerebrospinal fluid in the head)
• Abscess
• Chronic sinusitis
• Fracture
   

Risk Factors for Complications During the Procedure

Allergies, especially to x-ray dye, iodine, medications or certain foods including shellfish

Underlying kidney problems or diabetes may predispose you to a higher risk of decreased kidney function from the administered x-ray dye.

Bleeding disorder

What to Expect

Prior to Procedure

At your appointment before the test, your doctor will likely ask about:

• Your medical history
• Medications you take
• Allergies
• Whether you are pregnant or trying to get pregnant
   

In the days before your procedure

Follow your doctor?s instructions regarding any changes in how you take your medications and any restrictions on your eating and drinking.
 

At the health care facility

A health care professional explains the procedure and answers any questions you may have.

You may be asked to remove any article of clothing if it interferes with the image.  Modesty will be preserved.

You remove all jewelry, hair clips, dentures and other objects that could show on the x-rays and make them difficult to read.

Depending on which tissues your doctor wants to examine, you may be given a contrast dye.  If this is the case, do not eat or drink anything for 4 hours before your exams.

During Procedure

If a contrast dye is needed, it is injected into a vein.  You?ll be positioned on a special movable table, called a gantry, with your head, neck or back inside the CT scanner, which is usually doughnut-shaped. 

Anesthesia

None

 Description of the Procedure

The gantry advances you very slowly through the CT scanner.  You will need to be very still during the entire test.  If your have difficulty keeping your head perfectly still, the technologist may immobilize you.  As the scanner takes pictures, you will hear some humming and clicking. 

After the Procedure

The images are checked, and, if needed, they are repeated.

 If you have received contrast dye, drink extra fluids to flush it out of your body more quickly.

How long will it take? 

The scan takes approximately 5 minutes for head and sinus exams and slightly longer for spine.

Will it hurt? 

The scan will not hurt, though you might feel restless from not moving. 

Possible Complications

Complications are rare, but can include:

Allergic reaction to contrast dye

Kidney damage from contrast dye is rare, but more common in diabetic patients with prior kidney problems and in patients with rare blood disorders.  Please make sure your technologist and doctor know of any problem you may have which is similar to these.

Allergic or anaphylactic response to contrast dye can occur.  It is important to tell the technician/doctor if you have any allergies before the procedure only if you will receive contrast.

Average Hospital Stay

None

Postoperative Care

None

Outcome

The radiologist (doctor who specializes in working with medical images) will examine the images and report the finding to your personal doctor, usually within 24 hours.  Your doctor will discuss the finding with you and any treatment needed.

Call Your Doctor if any of the following occurs 

It is essential for you to monitor your recovery once you leave the health care facility.  In this way, you can alert your doctor to any problems right away.  If you received contrast dye, call your doctor immediately if any of the following occurs:

• Hives
• Itching
• Nausea
• Swollen or itchy eyes
• Tightness of the throat
• Trouble breathing