What is a Transcranial Doppler (TCD)?
It is used in the measurement of pressure and velocity in cerebral arteries. The test is quick, accurate and painless. TCD’s are used in the diagnosis of various conditions such as emboli, stenosis, vasospasm, headaches and subarachnoid hemorrhage.
It works by transmitting sound waves through the tissues of the skull. These sound waves reflect off the blood cells within the blood vessels and are than measured by the clinical technologist. There aren’t any special procedures to follow before the test and there are no side effects once the procedure is completed.
What happens during the TCD
- One can lie on a bed or sit in a chair during the examination.
- A small amount of non toxic water soluble gel will be applied to the area that is to be insonated.
- A transducer is than placed on the skin and a recording is taken for interpretation.
- The test lasts a few minutes and the results are interpreted by a neurologist.
- During the length of the test the patient has to remain still as this is needed for an accurate recording.
After the test
- The gel will be cleaned off and test results are discussed with the patients.