Quick answer
What is an ultrasound scan?
An ultrasound scan uses sound waves to create images of inside the body without using any radiation. It is used in pregnancy and to check for gallstones, DVT, organ problems, and to guide some procedures. Gel is applied to the skin and a probe is moved over the area, and the scan is usually painless.
How an ultrasound scan works
An ultrasound scan works by sending sound waves into the body, which reflect off different tissues to create an image. Because the images are produced in real time, the person carrying out the scan can move the probe to look at different areas as needed.
Common uses of ultrasound scans
Ultrasound scans are commonly used in pregnancy, and to examine the abdomen, pelvis, thyroid and for suspected DVT. They are also used to guide procedures such as biopsies, helping to make sure the right area is targeted.
Preparing for an ultrasound scan
You should follow the instructions in your appointment letter about eating beforehand and whether you need a full bladder. Wearing loose clothing on the day can also make the scan more comfortable and straightforward.
Limitations of ultrasound scans
Gas in the bowel can obscure the view during an abdominal ultrasound scan, making some areas harder to assess. Higher body weight can also sometimes reduce the quality of the images obtained.
Common questions about the ultrasound scan
- Does an ultrasound scan hurt?
- An ultrasound scan is generally painless, though the pressure from the probe can feel uncomfortable if it is moved over a tender area. Most people find the scan quick and straightforward.
- Do you need to fast before an abdominal ultrasound scan?
- Fasting for around six hours is often needed before a gallbladder ultrasound scan. You should always follow the specific instructions given in your appointment letter, as requirements can vary.
- What is an internal ultrasound scan?
- An internal ultrasound scan usually involves a transvaginal probe to examine the pelvis, giving clearer views in early pregnancy and for gynaecological conditions. It is a common and routine part of pregnancy and gynaecology care.
- When do you get the results of an ultrasound scan?
- Results are often discussed with you on the same day as your ultrasound scan. A more formal written report is then sent to the doctor who referred you.