Computed tomography (CT) is a diagnostic imaging test used to create detailed images of internal organs, bones, soft tissue and blood vessels.

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.

CT is based on the fundamental principle that the density of the tissue passed by the x-ray beam can be measured from the calculation of the attenuation coefficient.

A procedure that uses a computer linked to an x-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create 3-dimensional (3-D) views of tissues and organs.

Side effects of iodine contrast can include: skin rash or hives. itching. headache….Possible side effects of an abdominal CT scan

• abdominal cramping.
• diarrhea.
• nausea or vomiting.
• constipation.

The “cuts”(tomograms) for the CAT scan are usually made 5 or 10 mm apart. The CAT machine rotates 180 degrees around the patient’s body; hence, the term “axial.” The machine sends out a thin X-ray beam at 160 different points.

Coronal computed tomography (CT) scans are currently the optimal study to display the normal and abnormal anatomy in children with chronic and recurrent acute sinusitis after failure of medical therapy. Nine of these 12 children had increased attenuation in the maxillary sinus on soft-tissue windows.

In general, a CT scan has the advantage of short study time (15 to 20 minutes) with high quality images. However, disadvantages include the need for ra- diation exposure and the use of a contrast material (dye) in most cases, which may make it inappropriate for patients with significant kidney problems.

Axial non-volumetric scanning is how CT began where one (or just a few) slices are acquired during each gantry rotation. Traditional helical scanning (some call spiral) has the advantage of being faster than non volumetric axial scanning and also uses data continuously for improved motion robustness.

Spiral CT is a type of computed tomography (CT) scan. It is being used more and more in medical centers across the country to diagnose lung cancer. Spiral CT uses a faster machine that spins continuously around the body. This allows it to more quickly detect images and spot problems.

With helical CT, the patient is moved through a rotating x-ray beam and detector set. From the perspective of the patient, the x-ray beam from the CT traces a helical path. The helical path results in a three-dimensional data set, which can then be reconstructed into sequential images for a stack.

A computerized tomography (CT) or computerized axial tomography (CAT) scan combines data from several X-rays to produce a detailed image of structures inside the body. CT scans produce 2-dimensional images of a “slice” or section of the body, but the data can also be used to construct 3-dimensional images.

CT scans can detect bone and joint problems, like complex bone fractures and tumors. If you have a condition like cancer, heart disease, emphysema, or liver masses, CT scans can spot it or help doctors see any changes. They show internal injuries and bleeding, such as those caused by a car accident.

Preparing for a CT scan The water hydrates you prior to having contrast media for the CT. In the waiting area you will be asked to drink another 500ml of water which outlines the stomach and bowel clearly on the scans. The water also helps fill your bladder so that it shows on the scan.

Preparing for Your Exam For four hours prior to your exam, please do not eat solid foods. You may drink fluids such as water, juice, or black decaffeinated coffee or tea.

For a CT scan of your abdomen or pelvis you might need: a full bladder before your scan – so you might need to drink 1 litre of water beforehand. to drink a liquid contrast – this dye highlights your urinary system on the screen. to stop eating or drinking for some time before the scan.

A CT scan is usually done by a radiology technologist. You may need to take off any jewelry. You will need to take off all or most of your clothes, depending on which area is studied. You may be able to wear your underwear for some scans.

Elastic waist pants without zippers or snaps are another example of the preferred attire for a CT scan. If you arrive wearing clothing that has metal fastners, you will be asked to change into a hospital gown. It is best to leave all jewelry at home because you will be required to remove it before the procedure.