Overview
Because leukemia is a cancer of the blood cells, rather than one that routinely forms solid tumors, imaging studies - tests that obtain pictures of the inside of the body - are not always ordered. They are useful in some circumstances, however.
X-rays
A chest X-ray may be used to see if there is any sort of mass in the chest. X-rays may also be ordered to see if leukemia cells have affected the bones or if an infection is present.
Ultrasound
An ultrasound examination may be used to see if leukemia is affecting the kidneys or other organs. An ultrasound uses sound waves to create an image of internal tissues. It may be used in conjunction with a CT scan if a specific abnormality is found. During the test, a gel is first spread on the skin. A hand-held wand (transducer) is then slowly passed over the skin; it emits sound waves that bounce off tissues and back to the transducer. Different types of tissues reflect back different amounts of sound and that data is translated by a computer into an image. The examination is painless.
Computed Tomography (CT Scan)
A computed tomography scan may be used to see whether leukemia is affecting certain lymph nodes. A CT scan is essentially an X-ray, but rather than taking just one picture of the region, a special X-ray machine rotates around the patient and takes images from many different angles. The images are combined in a computer to create a 3-dimensional picture.
Magnetic Resonance Imaging (MRI)
An MRI may be used to see if the leukemia is affecting other parts of the body, such as the brain. An MRI uses a very large magnet to detect differences in tissues. During the exam the patient lies on a table that slides into a machine that contains the magnet. The magnet then causes certain elements in the cells to line up. Another device in the machine causes these elements to briefly wobble out of position. As they return to their lined-up position, the elements emit radio waves of various strengths. These waves are detected by the machine and are translated into an image on a computer. An MRI is painless, but some people are uncomfortable with the noise of the machine or having to stay still in a tube. Using earplugs or listening to music might help.
Echocardiogram
An echocardiogram may be used to measure how well a patient's heart is working before chemotherapy drugs are administered. It may also be used to see if any heart damage has occurred due to treatment. An echocardiogram uses ultrasound to form a picture of the heart and see how much blood is being ejected with each heartbeat. During the test, a gel is first spread on the skin. A hand-held wand (transducer) is then slowly passed over the skin; it emits sound waves that bounce off tissues and back to the transducer. Different types of tissues reflect back different amounts of sound and that data is translated by a computer into an image. The examination is painless.
