What Does a CT Head Scan Show?
A computerized axial tomography (CAT) or computerized tomography (CT) scan uses a series of X-rays taken at different angles to produce a detailed image of the head and brain.
The process of taking a CT scan of the head begins by taking many different X-ray views at various angles. These views are then combined using computer processing to create cross-sectional images, including the tissues inside of a solid organ.
A CT scan is done to study the patient’s skull, brain, jaw, sinuses, and facial bones. A doctor may recommend a head CT scan if a patient has any of the following symptoms:
- Recurrent headaches
- Seizures
- Head injury or injury to the face or eyes
- Dizziness or problems with balance
- Confusion
- Behavior or personality change
- Chronic nasal congestion
- Swelling in the face, head, or neck
This scan can also help to rule out other causes of headache that present symptoms like a migraine.
CT head scans are used for
- Investigating certain cancers or tumors of the skull, brain, and coverings over the brain.
- Identifying the location of tumors, stage of cancer, and site to perform a biopsy.
- Identifying congenital defects of the skull.
- Identifying hydrocephalus or bulging of the skull because of high pressure.
- Guiding doctors or surgeons during a procedure, such as a biopsy.
- Helping plan for certain types of therapy and surgery, as well as determining whether your body is responding to treatment.
- Detecting cysts or infections in the brain and identifying the bone structures within the skull.
- Quickly inspecting a patient after an accident to identify traumatic head injuries or any other internal injuries.
- Checking if the patient is displaying symptoms, such as
- hearing or vision loss,
- muscle weakness, or
- difficulty swallowing or speaking.
- Diagnosing conditions such as
- abnormal blood vessels,
- aneurysms,
- bone infection,
- brain damage,
- brain swelling,
- brain tumors, or
- stroke.
Special CT scans:
- They are done to study the paranasal sinuses. These are useful if sinusitis is suspected.
- A typical series of CT scans for the sinuses use less X-ray radiation than a standard complete set of X-rays. However, a CT scan of the sinuses does not show any brain tissues. Most CT scans of the head do not include all the sinuses.
- A CT scan with contrast may be ordered for people with strokes, hydrocephalus, or certain growths. These structures are better differentiated in a contrast CT scan.
CT scan side effects:
- CT scans use low levels of ionizing radiation. The risk of exposure to ionizing radiation, although small, is present. Any radiation is theoretically dangerous for body cells.
- On rare occasions, the contrast medium used for CT scans may cause an allergic reaction. The reaction may be severe enough in some people to cause kidney damage or even death.