Sonography
Sonography is a diagnostic medical test that employs high-frequency sound waves, known as ultrasound waves, to produce images of tissues, glands, organs, and blood or fluid flow within the body. This test is also called an ultrasound or sonogram.
During a sonography procedure, a device called a transducer is placed on the skin’s surface to emit ultrasound waves and capture their echoes. These waves are then converted into images by a computer. A trained technician can view, measure, and identify structures within these images, which are subsequently analyzed by a healthcare provider to diagnose potential issues or conditions.
Purpose of the Test
A sonogram captures live images of the body’s interior, functioning like a camera that takes real-time pictures of body parts or processes.
Sonography is valuable for assessing the size, shape, and density of tissues, aiding in the diagnosis of various medical conditions. Traditionally, ultrasound imaging excels at examining the abdomen without invasive procedures.
Abdominal ultrasounds are commonly used to diagnose:
- Gallbladder disease or gallstones
- Kidney stones or kidney disease
- Liver disease
- Appendicitis
- Ovarian cysts
- Ectopic pregnancy
- Uterine growths, fibroids, and other conditions
A sonogram is most frequently used to monitor the development of the uterus and fetus during pregnancy. It can also evaluate glands, breast lumps, joint conditions, bone diseases, testicular lumps, or guide needles during biopsies.
Sonography can detect blood or fluid flow toward or away from the transducer, using color overlays on the image to indicate the direction of the flow. However, very hard and dense tissues or empty spaces, such as gas-filled organs, do not conduct ultrasound waves and are not visible on a sonogram.
Physicians often order a sonogram before proceeding to imaging technologies with higher complication risks. For example, computerized tomography (CT) exposes patients to significant radiation levels.
Magnetic resonance imaging (MRI) uses a powerful magnet to capture images. The strength of an MRI magnet can restrict its use in patients with metal or devices in their bodies, such as certain pacemakers.
During the Test
A sonogram is performed bedside by a single technician. You will be asked to undress enough to expose the area to be examined and to lie down on the bed.
The technician will apply a conductive gel to the transducer, which feels similar to lubricant jelly. If possible, the gel will be warmed. The technician will then slide the transducer over your skin, sometimes applying firm pressure, which can occasionally cause mild discomfort.
The technician will use the transducer to highlight areas of interest, capturing images on a computer. They may use a mouse to draw lines across the screen for measurements, functioning like a virtual yardstick. You can watch the entire procedure and ask questions throughout.