What Is an Ultrasound?
An ultrasound scan is a medical test that uses high-frequency sound waves to create live images from the inside the body. Also called a sonogram or sonography, ultrasounds let doctors see the body’s soft tissues, which X-rays can’t do.
Doctors order ultrasounds for many reasons, such as to look for the causes of pain, swelling, and infection. Ultrasound scans are safe and painless.
What Is a Transcranial Doppler Ultrasound?
A transcranial Doppler ultrasound uses sound waves to evaluate blood flow (blood circulation) in and around the brain. The test is also called transcranial Doppler (TCD) ultrasonography. This test takes a bit longer to do than other types of ultrasounds. A TCD can take between 30 minutes to 1 hour.
Why Are Transcranial Doppler Ultrasounds Done?
Doctors order transcranial Doppler ultrasounds to check blood vessels when a problem is affecting blood flow to the brain. For children and teens, they might order the test:
- to screen kids and teens with sickle cell disease for their risk of stroke
- if someone has signs of an ischemic stroke (when blood flow is blocked to part of the brain)
- to look for blocked or narrowed blood vessels
- if a child had a traumatic brain injury
- to check brain function
What if I Have Questions?
If you have questions about the transcranial Doppler ultrasound or what the test results mean, talk to your doctor.