An ultrasound is a diagnostic tool, also referred to as
sonography. Ultrasound works to create
precise images using high-frequency sound waves. Doctors use this imaging technique to examine body structures so that they can diagnose various health conditions or determine the overall health of the patient.
Some ultrasounds are internal, but in most cases, the ultrasound device is used on the outside of the body to get images.
Ultrasound can be done for dozens of diseases and conditions. The most common reasons for an ultrasound include:
- Assessing the unborn baby (fetus) during pregnancy
- Evaluating blood flow in the blood vessels
- Evaluating a breast lump
- Studying the heart
- Diagnosing certain types of cancer
- Evaluating tendon and muscle abnormalities
- Diagnosing gallbladder disease
- Guiding a needle for treatments or biopsies
- Checking the thyroid
- Diagnosing certain types of infection
- Looking for certain prostate and genital abnormalities
Ultrasound is considered as a very safe diagnostic technique and there are no direct risks associated with this type of imaging. No ionization radiations (e.g. X-rays) are used and the images are created directly from sound waves.
The biggest issue with ultrasound is that it comes with limitations. Any part of the body that contains gas and bones do not respond well to ultrasound because sound waves do not travel through bone or air well. If a doctor needs to analyze such areas of the body, different imaging techniques must be used to ensure adequate pictures.
Preparation depends on the part of the body that your doctor orders to be examined. For most parts of the body, ultrasound testing does not require any preparation, but preparations are generally necessary for the following:
- Gallbladder: About six hours prior to your ultrasound, the patient will need to avoid food and drinks.
- Pelvic: If the doctor ordered a pelvic ultrasound, the patient will need a full bladder. This acts like a window for better visualization of the ovaries, uterus and prostate.
The procedure begins with the patient lying on an examination table. The ultrasound technician will apply water-based gel to the skin in the area where the ultrasound will be done. This gel is necessary to allow the ultrasound probe to glide and to prevent air pocket formation between the body and the probe. The technician presses the probe against the skin and moves it around as necessary to get the right pictures. Most ultrasounds are performed this way, but there are a few other kinds of ultrasound your doctor may order to get images of specific parts of the body.
These different types include:
- Transesophageal Echocardiogram: This ultrasound works to get pictures near your heart. The technician inserts the specific type of probe (wand part) of the machine into the esophagus. Since this is a bit more invasive than a traditional ultrasound, the patient typically receives sedation before the procedure.
- Transvaginal Ultrasound: This works to view the ovaries and uterus.
- Transrectal Ultrasound: This is done to get images of the prostate gland. Ultrasound
After the examination, the radiologist at the clinic or hospital will review the images and send the final results to the doctor. The doctor will explain the results to the patient.