CT scan
A computerized tomography (CT) scan combines a series of X-ray images taken from different angles around your body and uses computer processing to create cross-sectional images (slices) of the bones, blood vessels and soft tissues inside your body. CT scan images provide more-detailed information than plain X-rays do.
A CT scan can be used for a variety of purposes, but it's especially useful for quickly examining patients who may have internal injuries as a result of vehicle accidents or other sorts of trauma. A CT scan can visualise almost every region of the body and is used to diagnose sickness or injury as well as plan medical, surgical, or radiation treatment.
Why it's done
Your doctor may recommend a CT scan to help:
- Diagnose muscle and bone disorders, such as bone tumors and fractures
- Pinpoint the location of a tumor, infection or blood clot
- Guide procedures such as surgery, biopsy and radiation therapy
- Detect and monitor diseases and conditions such as cancer, heart disease, lung nodules and liver masses
- Monitor the effectiveness of certain treatments, such as cancer treatment
- Detect internal injuries and internal bleeding
Risks
Radiation exposure
During a CT scan, you are exposed to ionising radiation for a brief period of time. Because the CT scan gets more precise information, the amount of radiation is higher than an ordinary X-ray. Low levels of radiation used in CT scans have not been proved to cause long-term harm, however much greater doses may result in a modest increase in cancer risk.
CT scans have numerous advantages that outweigh any minor risk. To gather the necessary medical information, doctors employ the least amount of radiation possible. In addition, newer, faster machines and processes consume less radiation than older machinery and techniques. Discuss the benefits and dangers of your CT scan with your doctor.
Harm to unborn babies
If you're expecting a child, tell your doctor. Although the radiation from a CT scan is unlikely to harm your baby, your doctor may recommend an ultrasound or an MRI instead to minimise exposing your baby to radiation. Humans have shown no detrimental consequences from the tiny levels of radiation used in CT imaging.
Reactions to contrast material
In some situations, your doctor may prescribe that you receive contrast material, which is a specific dye. This could be anything you drink before your CT scan, or it could be something injected into your rectum through a vein in your arm. Contrast material can create medical complications or allergic reactions, albeit this is uncommon.
The majority of responses are modest, resulting as a rash or itching. An allergic reaction can be serious, even life-threatening, in rare cases. If you've ever had a reaction to contrast material, tell your doctor.