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Ultra Sound

An ultrasound test is a radiology technique, which uses high- frequency sound waves to produce images of the organs and structures of the body. The sound waves are sent through body tissues with a device called a transducer. The transducer is placed directly on top of the skin, which has a gel applied to the surface. The sound waves that are sent by the transducer through the body are then reflected by internal structures as "echoes." These echoes return to the transducer and are transmitted electrically onto a viewing monitor. The echo images are then recorded on a plane film and can also be recorded on videotape. After the ultrasound, the gel is easily wiped off.

The technical term for ultrasound testing and recording is "sonography." Ultrasound testing is painless and harmless. Ultrasound tests involve no radiation and studies have not revealed any adverse effects

For what purposes are ultrasounds performed?

Ultrasound examinations can be used in various areas of the body for a variety of purposes. These purposes include examination of the chest, abdomen, blood vessels (such as to detect blood clots in leg veins) and the evaluation of pregnancy. In the chest, ultrasound can be used to obtain detailed images of the size and function of the heart. Ultrasound can detect abnormalities of the heart valves, such as mitral valve prolapse, aortic stenosis, and infection (endocarditis). Ultrasound is commonly used to guide fluid withdrawal (aspiration) from the chest, lungs, or around the heart. Ultrasound is also commonly used to examine internal structures of the abdomen. Gallstones in the gallbladder are easily detected, as are kidney stones. The size and structure of the kidneys, the ureters, liver, spleen, pancreas, and aorta within the abdomen can be examined. Ultrasound can detect fluid, cysts, tumors or abscess in the abdomen or liver. Impaired blood flow from clots or arteriosclerosis in the legs can be detected by ultrasound. Aneurysms of the aorta can also be seen. Ultrasound is also commonly used to evaluate the structure of the thyroid gland in the neck.

How does a patient prepare for CAT scanning, and how is it performed?

In preparation for a CAT scan, patients are often asked to avoid food, especially when contrast material is to be used. Contrast material may be injected intravenously, or administered by mouth or by an enema in order to increase the distinction between various organs or areas of the body. Therefore, fluids and food may be restricted for several hours prior to the examination. If the patient has a history of allergy to contrast material (such as iodine), the requesting physician and radiology staff should be notified. All metallic materials and certain clothing around the body are removed because they can interfere with the clarity of the images.
Patients are placed on a movable table, and the table is slipped into the center of a large donut-shaped machine which takes the x-ray images around the body. The actual procedure can take from a half an hour to an hour and a half. If specific tests, biopsies, or intervention are performed by the radiologist during CAT scanning, additional time and monitoring may be required. It is important during the CAT scan procedure that the patient minimize any body movement by remaining as still and quiet as is possible. This significantly increases the clarity of the x-ray images. The CAT scan technologist tells the patient when to breathe or hold his/her breath during scans of the chest and abdomen. If any problems are experienced during the CAT scan, the technologist should be informed immediately. The technologist directly watches the patient through an observation window during the procedure and there is an intercom system in the room for added patient safety.