An ultrasound scan (USS) uses sound waves to create accurate 3D images of small areas of the inside of your body. The sound waves bounce off tissues inside your body and it is how the sound waves bounce back from surfaces that are measured creating the image. The sound waves are extremely high frequency so you will not be able to hear them. Ultrasound scanning is extremely safe, pain-free, and does not use any radiation (unlike X-ray, PET, and CT scan). Ultrasound scanning can be used for looking at many areas of the body, in particular, monitoring a baby’s progression in pregnancy, looking at certain organs or lumps to help with diagnosing, and looking at muscle, joint, and tendon injuries.
Most ultrasounds are done externally on the body where a gel is put onto the skin (which usually feels cold!) and then an ultrasound probe rolls over this gel and produces an image on a screen. A small number of ultrasounds are done internally when looking at specific areas such as a transvaginal ultrasound that can be used to look at the uterus (womb) or an endoscopic ultrasound which is a very small ultrasound probe that can go through the mouth to look at your oesophagus.
There are no risks associated with ultrasound scans so they can be used in anyone when needed. If you are having the much less common endoscopic ultrasound, you may be given some sedation which will come with its own risks and will be explained to you prior to the scan.