Related Experiment Video
Updated: May 28, 2026
07:44
Assessment of Cerebral Lateralization in Children using Functional Transcranial Doppler Ultrasound (fTCD)
Published on: September 27, 2010
Problems with implementing a standardised transcranial Doppler screening programme: impact of instrumentation
Soundrie T Padayachee1, Nicholas Thomas, Andrew J Arnold
1Ultrasonic Angiology Department, Borough Wing, Guy's Hospital, Guy's & St Thomas' NHS Foundation Trust, St Thomas Street, London, UK. soundrie.padayachee@gstt.nhs.uk
Pediatric Radiology
|October 18, 2011
Summary
Lowering transcranial Doppler (TCD) imaging velocity thresholds for sickle cell anemia screening may lead to unnecessary transfusions. Validating TCD practices is crucial for accurate patient selection in stroke prevention.
Area of Science:
- Neurology
- Pediatrics
- Hematology
Background:
- The Stroke Prevention Trial in Sickle Cell Anaemia (STOP) established transcranial Doppler (TCD) ultrasound screening for selective transfusion.
- Differences between imaging and non-imaging TCD have led some centers to lower imaging velocity thresholds.
Purpose of the Study:
- To retrospectively compare velocity measurements from non-imaging and imaging TCD using a standardized protocol.
- To assess how varying velocity thresholds impact STOP classification for sickle cell anemia patients.
Main Methods:
- Reviewed TCD data from 23 pediatric patients (ages 2-19).
- Focused on a protocol to capture the highest audible Doppler frequency.
- Applied STOP velocity thresholds and values reduced by 5-15% for comparison.
Main Results:
- Non-imaging and imaging TCD velocities showed a close correlation with minimal bias.
- Lowering imaging TCD velocity thresholds increased abnormal and conditional classifications.
- Abnormal TCD imaging classifications varied from 1.9% to 37% based on threshold adjustments.
Conclusions:
- Current methods of applying STOP thresholds to imaging TCD may be unnecessary.
- Centers must validate their imaging TCD protocols to prevent inappropriate patient selection for transfusions.
