How is the procedure performed?
Patients must remove their clothing and most medical centers will give the patient a loose-fitting gown to wear. They will also be asked to remove all metallic jewelry that may interfere with the x-rays. Normally, the patient will stand with the chest pressed to the photographic plate, with hands on hips and elbows pushed in front in a somewhat exaggerated position. The technologist will ask the patient to be still and to take a deep breath and hold it. This not only reduces the possibility of a blurred image but also enhances the quality of the image since air-filled lungs are easier to see on x-ray film than deflated lungs. Next, the technologist will go to another small room or cubicle and activate the radiographic equipment, which will send a beam of x-rays from behind the patient, through the patient’s chest, to the film behind the plate, thus exposing the film. Some newer equipment is designed to accommodate patients who cannot stand for chest x-rays.
A.A nurse or technologist will take you into a special PET examination room. You will lie down on an examination table and be given the radioactive substance as an intravenous injection (although, in some cases it will be given through an intravenous line or inhaled as a gas). It will then take qpproximately 30-60 minutes for the substance to travel through your body and be absorbed by the tissue under study. After that time, scanning begins. This takes an additional 30-45 minutes.Some patients, specifically those with heart disease, may undergo a stress test in which PET scans are obtained while they are at rest, then after undergoing the administration of the pharmaceutical, to alter the blood flow to the heart.Usually, there are no restrictions on daily routine after the test, although you should drink plenty of fluids to flush the radioactive substance from your body.
The patient is usually positioned on an examination table. A clear gel is applied to the patient’s body in the area to be examined to help the transducer make secure contact with the skin. The sound waves produced by the transducer cannot penetrate air so the gel helps eliminate air pockets between the transducer and the skin. The technologist or radiologist presses the transducer firmly against the skin and sweeps it back and forth to image the area of interest. When the examination is complete the patient may be asked to dress and wait while the ultrasound images are reviewed either on film or on a TV monitor. Often though, the technologist or radiologist is able to review the ultrasound images in real time as they are acquired and the patient can be released immediately.
After positioning the patient on the adjustable examination table, the technologist will apply a liquid jelly to the skin to make close contact between the skin and transducer, eliminating air pockets. This will ensure that the sound waves are freely conducted into and out of the body. The radiologist or technologist presses the transducer firmly to the skin and moves it back and forth to obtain complete images of areas of interest. The entire area of interest will be scanned, obtaining images from different perspectives. Sometimes the examiner may want to obtain images while you are standing upright. You will be asked to relax and remain calm during the examination. The radiologist also may ask you health-related questions during the exam and may repeat some images to clarify the findings.
(A) The technologist positions the patient on the examination table, places a film holder (cassette) under the table in the area of the body to be imaged. Then the technologist steps behind a radiation barrier and asks the patient to hold very still without breathing for a few seconds. The x-ray equipment is activated, sending a beam of x-rays through the body to expose the film. The technologist then repositions the patient for another view, and the process is repeated.
