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Ct Scan: Head

A CT scan of the head produces an image of a cross section of the skull and brain and is a safe procedure. It uses x-ray beams, but provides much more detail than a standard x-ray film. A CT scan helps diagnose various problems, such as tumors, blood clots, or injured tissue.

CT is short for computerized tomography. The procedure allows x-rays to be taken all around the head while lying inside a long x-ray unit or tube. It sends many beams though the same area. The beams are detected on the other side of the head and analyzed by computer. The computer translates the image to a film that contrasts various tissue types in different shades.

CT scans of the head are used to:

• diagnose various brain abnormalities

• monitor the effects of surgery or cancer therapy

• assess nerve problems that suggest a brain tumor and

• find internal bleeding after a head injury

Scanning typically lasts from 15 to 30 minutes and is painless. The person may receive an injection of dye before the scan. If so, the person is instructed to fast for 4 hours before the test. People who are allergic to shellfish may also be sensitive to the dye. The dye may cause warm feelings, flushed face, headache, a salty taste in the mouth, or nausea and vomiting.

During a CT scan, the patient lies still on a table. Before the test all jewelry must be removed. The table slides into the CT unit, which is like a small tunnel or donut. It is important not to move during the scan, although you can breathe normally. The scanner rotates around the table, and may make noises. The patient can talk to the technician at any time during the procedure. If a person becomes panicky, the procedure may be stopped. The doctor may give a mild sedative to restless or anxious people.

After a CT scan, one should watch for signs of delayed reaction to the dye. These include itching, rash, sweating, or difficulty breathing. The patient should drink plenty of fluids to rid the body of the dye.

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