transcranial Doppler
Also written as: TCD — transcranial Doppler
Non-invasive ultrasound technique used to measure blood flow velocity in cerebral arteries for stroke risk assessment in sickle cell disease.
Full Definition
Transcranial Doppler (TCD) ultrasonography is a non-invasive imaging technique that uses pulsed Doppler ultrasound to measure blood flow velocities in the major intracranial arteries. In pediatric sickle cell disease management, TCD is the standard screening tool for identifying children at high risk for stroke. Elevated time-averaged mean maximum velocities (≥200 cm/s) in the middle cerebral or internal carotid arteries indicate increased stroke risk and warrant initiation of chronic transfusion therapy. Annual TCD screening is recommended for children with sickle cell disease ages 2-16 years.
Usage
Usage note: Capitalize Doppler (proper name). Can abbreviate as TCD after first mention.
In Context
- "Annual transcranial Doppler screening showed normal velocities in both middle cerebral arteries." — Sickle cell clinic note
- "The TCD revealed elevated velocities requiring initiation of chronic transfusion therapy." — Stroke prevention protocol