A computed tomography (CT) angiograph is an imaging device that provides a comprehensive look at the blood vessels and arteries in different parts of the body, such as the heart and brain. This type of scan is used to diagnose a wide range of medical conditions. Computed tomography angiograms provide a noninvasive review of the body with only a minimal exposure to radiation.
Just before a CT angiography scan, a nurse will attach an intravenous line to the arm to administer a dye, called a contrast medium. This dye will travel through the circulatory system and improve the contrast and details of the images. The patient will then be slid into the CT machine for the CT angiography procedure, which takes about 30 minutes. Once the scan is complete, the patient is free to leave.
During the scan, x-rays and x-ray detectors will revolve around the patient. The detectors will record the amount of x-ray radiation that is taken up by the body and produce an image. The image will represent a slice through the body, much like a slice of bread. Gradually the patient will be moved through the CT tube so that many slices can be gathered. The slices will then be reconfigured using a computer program to create multidimensional views of the circulatory system.
CT angiography is used to diagnose many different medical conditions. This procedure can be used to check for aneurisms, blockage of the arteries, or any abnormality in the pattern of the blood vessels. Angiography scans can also help prepare surgeons for heart surgery or for organ transplants by showing the exact location of blood vessels. An oncologist may also use a CT angiography to review the vascularization of a malignant tumor.
Angiography coupled with a CT scan has many benefits. This diagnostic tool can eliminate, in a noninvasive way, the need for some types of exploratory surgeries once used to look at the health of the circulatory system. The procedure also eliminates the need for a catheter-dependent angiography and, in almost all cases, this procedure provides greater details than a catheter angiography.
There are a few risks of using this imaging device, however. The patient is exposed to a low level of radiation during the test. In addition, some patients have an allergic reaction to the contrast medium used during the exam. If this occurs, the allergy should be noted on the patient’s medical records to avoid future problems. Finally, some patients are uncomfortable in the enclosed space of the scanner and can become anxious and uncomfortable. This can be avoided by giving the patient a sedative prior to the scan.
To prepare for a CT angiography, a patient should wear comfortable, loose-fitting clothing that will allow access to the arms for the injection. If a sedative is to be given, the patient should follow all guidelines given in preparation for the medication, such as fasting or bringing a friend to drive him home. Any pain or discomfort at the injection site during the procedure or following the test should be reported to the doctor.