Diagnostic Imaging

OLYMPUS DIGITAL CAMERAUltrasound / Echocardiogram

This is a noninvasive test that uses sound waves to produce a study of the motion of the heart’s chambers and valves, as well as the flow of blood inside the heart. It is also used to detect fluid around the heart. Images are obtained by passing an ultrasound transducer over the chest area overlying the heart.

An echocardiogram may either be done alone or in association with a stress test. There is no need for any particular preparation. The study takes from 30 to 60 minutes. The data is reviewed by your physicians and recommendations are made based on your clinical presentation and the indication for the test.

The test is very good at detecting valvular problems, either leakage or narrowing, as well as determining if any particular areas of the heart muscle have suffered a heart attack or are simply not working properly due to a blockage in the artery supplying that area of the heart.

Nuclear Imaging

Nuclear ImagingBy detecting radiation from different parts of the body following the administration of a radioactive tracer material, images of internal organs are produced. Other imaging techniques are able to show how organs appear, but nuclear imaging is able to evaluate how organs function. It is a safe procedure with no side effects.

 

A special camera is used to scan the body and take a number of pictures. Connected to the camera is a computer which detects the radiation from the specific body area being examined. A series of images are formed based on this information. This technique measures the biochemistry and physiology of the heart muscle and is used to assess the overall condition of the heart.

Toshiba 64-Slice CT

What does the equipment look like?

64slicectpicA CT scanner is a specialized x-ray machine that looks like a large square doughnut. It has an opening measuring about two feet in diameter that surrounds a narrow table. Inside the frame of the scanner is a rotating device with an x-ray tube mounted on one side and a banana-shaped detector opposite it. CTA studies use an advanced type of unit called a spiral CT machine that looks like any other type of CT unit, but is able to record a large number of pictures in a short time. This means that patients do not have to hold their breath for a prolonged period.

How does the procedure work?

Before the actual exam begins, you will have a dose of contrast material injected into a vein to make the blood vessels stand out. An automatic injector machine is used that controls the timing and rate of injection, which may continue during part of the time images are recorded. During the examination, the rotating device spins around the patient, creating a fan-shaped beam of x-rays, and the detector takes snapshots of the beam after it passes through the patient. As many as one thousand of these pictures may be recorded in one turn of the detector. The real work of CTA comes after the images are acquired, when powerful computer programs process the images and make it possible to display them in different ways, for instance, in cross-sectional slices or as three-dimensional “casts” of the blood vessels.

How is the procedure performed?

Most of the time for a CTA examination is spent setting everything up. Actually recording the images takes only seconds. After changing into a hospital gown and having an IV set up, you will answer questions about things that might complicate the exam (such as allergies) and then will lie down on a narrow table. The part of your body to be examined will be placed inside the opening of the CT unit with the aid of criss-crossed positioning lights. A test image is taken to determine the best position, and a small dose of contrast material is given to see how long it takes to reach the area under study. Then the IV is hooked up to an automatic injector, contrast material is injected, and the scan begins. Afterwards, the images will be reviewed and, if necessary, some will be repeated. No special measures are needed after the procedure.

What will I experience during the procedure?

ctheartCTA takes about 10 to 25 minutes from the time the actual examination begins. Overall, you can expect to be in or near the examining room for 20 to 60 minutes. You may feel warm all over when contrast material is injected before the scan, but you should not feel pain at any time. Any CT study requires that you remain still during the exam. Pillows and foam pads may help make it more comfortable. At the same time the nurse or technologist may use pads or Velcro straps to keep the area from moving. The examination table will move into and out of the scanner opening, but it is not enclosed and only a small part of your body will be inside at any one time. You may be asked to hold your breath for nearly 10 seconds to be sure that the images will not be blurred. During the time that no actual imaging is taking place you are free to ask questions or talk to the technologist, but friends or relatives will not be allowed in the examining room. Once the needed images have been recorded, you will be free to leave. You can eat immediately and it is a good idea to drink plenty of fluids in the hours after the exam to help flush contrast material out of the system.

Who interprets the results and how do I get them?

Typically the results of CTA are available within 24 hours, although in complicated cases special computer analysis may take somewhat longer. The cardiologist will report the findings to you or to your referring physician, who in turn will discuss them with you.