A non-invasive procedure that uses high-frequency sound waves to assess different structures in the body. Diagnostic ultrasound is an imaging method that produces images of structures within your body. These images provide valuable information for diagnosing and treating a variety of diseases and conditions.
Most ultrasound examinations are done using an ultrasound device outside your body, although some examinations involve placing a device inside your body.
Ultrasound is used for many reasons, including to:
- View the uterus and ovaries during pregnancy and monitor the developing baby’s health
- Diagnose gallbladder disease
- Evaluate blood flow
- Check your thyroid gland
- Detect genital and prostate problems
- Evaluate metabolic bone disease
Types of Ultrasounds
Abdominal Ultrasound
An abdominal ultrasound is a useful way of examining internal organs, including the liver, gallbladder, spleen, pancreas, kidneys, and bladder. Because these images are captured in real time, they can show movement of internal tissues and organs and enable physicians to see blood flow. This can help diagnose a variety of conditions and assess damage caused by illness.
Obstetric Ultrasound
Obstetric ultrasound refers to the specialized use of sound waves to visualize and determine the condition of a pregnant woman and her embryo or fetus. Obstetric ultrasound should be performed only when clinically indicated, such as to:
- Establish the presence of a living embryo/fetus
- Estimate the age of the pregnancy
- Diagnose congenital abnormalities
- Evaluate the position of the fetus
- Evaluate the position of the placenta
- Determine if there are multiple pregnancies
Pelvic Ultrasound
For women, pelvic ultrasound is most often used to examine the uterus and ovaries, and during pregnancy, to monitor the health and development of the embryo or fetus. Millions of expectant parents have seen the first “picture” of their unborn child thanks to pelvic ultrasound examinations.
For men, a pelvic ultrasound usually focuses on the bladder and the prostate gland. There are three methods of performing pelvic ultrasound: abdominal (transabdominal), vaginal (transvaginal, endovaginal) in women, and rectal (transrectal) in men. The same principles of high-frequency sound apply in each technique.
Vascular (Carotid & Abdominal Aorta) Ultrasound
Ultrasound of the carotid arterial system provides a fast, non-invasive means of identifying blockages of blood flow in the neck arteries to the brain that might produce a stroke or mini-stroke. Ultrasound of the abdominal aorta is primarily used to evaluate for an aneurysm, which is an abnormal enlargement of the aorta usually from atherosclerotic disease.
BEFORE THE TEST
There are different types of ultrasound tests. Some tests will require no preparation, some will require you to drink large amounts of liquid prior to the test, and others will require you to not eat or drink for hours before the test. Consult your physician for any specific instructions for your particular test.
Before your ultrasound begins, you may be asked to remove jewelry from the area being examined. You may also be asked to remove your clothing and wear a gown.
DURING THE TEST
You’ll be asked to lie on an examination table. Gel is applied to your skin over the area being examined. It helps prevent air pockets, which can block the sound waves that create the images. This water-based gel is easy to remove from skin and, if needed, clothing.
A trained technician (sonographer) presses a small, hand-held device (transducer) against the area being studied and moves it as needed to capture the images. The transducer sends sound waves into your body, collects the ones that bounce back, and sends them to a computer, which creates the images.
Sometimes, ultrasounds are done inside your body. In this case, the transducer is attached to a probe that’s inserted into a natural opening in your body. Examples include:
- Transesophageal Echocardiogram – A transducer, inserted into your esophagus, obtains heart images. It’s usually done while you are sedated.
- Transvaginal Ultrasound – A special transducer is gently inserted into the vagina to get a quick look at the uterus and ovaries.
Ultrasound is usually painless. However, you may experience mild discomfort as the sonographer guides the transducer over your body, especially if you’re required to have a full bladder, or inserts it into your body. A typical ultrasound exam takes between 30 minutes to 1 hour.
AFTER THE TEST
Once the test is completed, you may return to your normal activities.