An ultrasound scan uses high-frequency sound waves to create images inside the body
It's safe, painless, and doesn't use any radiation
It's used to examine organs, muscles, and joints, or to monitor a baby during pregnancy
It can also help guide certain procedures, such as a steroid injection
There are three main types: external, internal, and endoscopic ultrasound
About Ultrasound Scans
An ultrasound scan uses high-frequency sound waves, which can't be heard by the human ear, to build a detailed picture of the inside of the body. It's a safe and generally painless method of imaging, and unlike X-rays or CT scans, it doesn't involve any radiation.
Ultrasound is used widely to examine organs such as the liver and kidneys, muscles and joints, and to monitor a baby's development during pregnancy. It's also sometimes used to help guide certain procedures, such as accurately positioning a needle for a steroid injection.
Page last reviewed: 6 March 2024 · Next review due: 6 March 2027
Ultrasound · Types
Types of Ultrasound Scan
? 4 min readReviewed: March 2024
External, Internal and Endoscopic Scans
An external ultrasound scan is the most common type, where a small handheld probe is placed on the skin and moved gently over the area being examined — this is often used to look at the heart, an unborn baby, or organs in the tummy and pelvis.
An internal ultrasound scan involves placing the probe inside the body, which can give a clearer view of certain areas, such as the womb or prostate. An endoscopic ultrasound combines an ultrasound probe with a thin, flexible tube (an endoscope), allowing it to be passed further into the body, such as into the digestive system, for a more detailed examination.
Page last reviewed: 6 March 2024 · Next review due: 6 March 2027
Ultrasound · Preparation
Preparing for Your Scan
? 4 min readReviewed: March 2024
Getting Ready
Preparation depends on which part of the body is being scanned. For an abdominal scan, you may be asked not to eat for several hours beforehand, while a scan of the pelvis or urinary tract often requires a full bladder, meaning you'll need to drink plenty of fluids and avoid the toilet shortly before your appointment. Your appointment letter will explain exactly what's needed for your particular scan.
During the scan, a gel is applied to your skin to help the probe make good contact, and you may be asked to hold your breath briefly, or change position, to get the clearest images. It's not usually painful, though it might feel a little uncomfortable if the probe presses on an area that's already sore. You're welcome to ask for a chaperone to be present if you'd like one. Results are sent to the doctor who referred you, and you may need a follow-up appointment to discuss what they mean.
Page last reviewed: 6 March 2024 · Next review due: 6 March 2027
