What is transcranial doppler ultrasound (TCD)? 1,2
- TCD is a non-invasive ultrasonic technique measuring local blood flow velocity and direction in the proximal portions of large intracranial arteries.
- TCD’s principal use is in the evaluation and management of patients with cerebrovascular disease.
- A pulsed wave transducer emits waves, and then receives their reflections off the surfaces of the red blood cells within the intracranial vasculature. This information is subsequently analyzed by the Lucid system to give us both numerical and visual output.
Advantages and Limitations of Transcranial Doppler Ultrasound 1,2
Advantages of TCD:
- can be performed at the bedside
- easily repeated or used for continuous monitoring
- is generally less expensive than other techniques
- contrast agents are not used avoiding allergic reactions and decreasing risk to the patient
Limitation of TCD:
- examination of cerebral blood flow velocities in certain segments of large intracranial vessels
- detects indirect effects (abnormal waveform characteristics) suggesting of proximal hemodynamic or distal obstructive lesions
- more valuable in specific conditions
Studies have shown that transcranial doppler ultrasound is not hazardous. There are no harmful side effects. In addition, ultrasound does not use radiation, as X-ray tests do.
Neural Analytics is committed to pioneering the expansion of the transcranial doppler ultrasound procedure with the Lucid System™ to expedite rapid brain health assessment.
1 Radiological Society of North America. Cranial Ultrasound/Head Ultrasound Accessed 2/14/2017.
2 Purkayastha S, Sorond F. Transcranial Doppler Ultrasound: Technique and Application. Semin Neurol. 2012 Sep; 32(4): 411–420.