There are two tests that can help assess the blood flow to and in your brain. These tests may also help identify a heart problem that can affect the blood in your brain.
What is a Transcranial Doppler Study (TCD)?
A transcranial doppler study (TCD) is a safe, painless test that evaluates the blood flow to and in your brain. This test uses high-frequency sound waves that you can’t hear or feel. As the sound waves bounce off blood vessels, information is sent to a computer screen. Analyzing the information helps your doctor look for problems that might keep your brain from getting enough oxygen.
Your doctor might use a TCD study to assess:
The TCD test is also used to monitor blood flow in the brain during surgery or after a head injury.
What is a bubble study?
A bubble study is a TCD that includes injecting tiny bubbles into a blood vessel. The sound waves show whether the bubbles reach your brain.
This test is most often used to find out if you have an abnormal opening between the chambers of your heart. Normally, oxygen-poor blood comes to the right side of your heart, which sends it to the lungs to get oxygen. The oxygen-rich blood returns to the left side of your heart, which pumps it to your body. An abnormal opening can allow oxygen-poor blood to leak over to the left side. This leaked blood misses the trip to the lungs, so it’s pumped to your body without picking up the oxygen your body needs.
Because the lungs dissolve bubbles in the blood, we can use injected bubbles to see if any blood is skipping its trip to the lungs. If this happens, it means your brain is getting oxygen-poor blood.
Why might I need a TCD or bubble study?
Your doctor might recommend this test if:
What happens during a TCD study?
A TCD study takes about an hour. Here’s what happens:
The sides of your head above your ears, Under your chin, The hollows on the back of your neck (you’ll sit or lie on your side and hold your head down), or on your closed eyelids (don’t worry – the gel won’t hurt your eyes, and the transducer is moved very lightly over the skin)
What happens during a bubble study?
A bubble study takes about 20 to 30 minutes. Here’s what happens during the test:
What happens after the test?
After either type of test, here’s what happens:
Talking with your doctor about the test
The list below shows the most common potential benefits, risks and alternatives for TCD and bubble studies, but other benefits or risks may apply in your unique medical situation. Talking with your doctor is the most important part of learning about the test. If you have questions, be sure to ask.
A TCD or bubble study can:
Risks and potential complications
TCDs and bubble studies are very safe. Risks include:
Alternatives to TCD may include:
Alternatives to the bubble study may include:
For further information please contact Cardiac Center of Texas at 972-529-6939 or send us a question through the patient portal under the Patients tab at the top of the page. Thank you for visiting CardiacCenterOfTexas.com.