What is an ultrasound scan?
An ultrasound scan is a procedure that uses high-frequency sound waves to create an image of part of the inside of the body.
Ultrasound scans can be used to monitor unborn babies, diagnose a condition, or guide a practitioner during certain procedures.
How ultrasound scans work
A small device called an ultrasound probe is used. High-frequency sound waves come out of the probe.
You can’t hear these sound waves, but when they bounce off different parts of the body, they create “echoes” that are picked up by the probe and turned into a moving image. This image is displayed on a monitor while the scan is carried out.
It may be necessary for you to lie in different positions and you may be asked to hold your breath while pictures are taken.
Before the scan, you may be asked to follow certain instructions to help improve the quality of the images produced. For example, you may be advised to:
- Drink water and not go to the toilet until after the scan.
- Avoid eating or drinking for several hours before the scan.
Your ultrasound scan
Ultrasound scans are carried out slightly different depending upon the condition you are being scanned for.
Different types of scan include:
- General ultrasound scans
- Vascular ultrasound scans
- Musculoskeletal ultrasound scans
- Ultrasound guided biopsy
- Ultrasound guided fine needle aspiration (FNA) or biopsy of neck
- Ultrasound guided injection of local anaesthetic or steroid medication
