A Transcranial Doppler (TCD) test is a painless, non-invasive ultrasound that allows doctors to evaluate cerebral blood flow, helping diagnose and manage conditions such as strokes, traumatic brain injuries, and other cerebrovascular disorders.
A technician will apply gel to your skin (temples, eyelids, neck) and move a wand (transducer) over these areas, sending sound waves through your skull to measure blood flow in your brain's arteries.
A TCD can take between 30 minutes to 1 hour to complete, sometimes involving an IV line.
How the Test is Performed:
- You lie on your back on a padded table with your head and neck on a pillow.
- The technician applies a water-based gel on your temples.
- Some tests may include bubble studies (injecting saline) to check for heart-to-brain vascular pathways.
- A transducer is moved over the area being tested. The transducer sends out sound waves. The sound waves go through your body and bounce off the area being studied (in this case, your brain and blood vessels).
- A computer looks at the pattern that the sound waves create when they bounce back.
- You may be asked to move or lift your arms to see if there are any changes with position.
- The test can take 30 minutes to 1 hour to complete. No special preparation is needed for this test.