What is the more common method of obtaining velocity measurements in carotid artery studies; a 60 degree insonation angle versus a convenient insonation angle?

Introduction: Stenosis of the internal carotid arteries (ICAs) increases the risk of stroke. ICA stenosis is routinely assessed with Doppler ultrasound. The current need for diagnostic imaging accuracy and unity is invaluable. Limits are in place to complete ultrasound examinations using insonation angles of 60° or less. The diagnostic community is separated into two groups: (1) those that use a constant 60° angle and (2) those that use an angle of 60° or less. Methods: A pilot study was undertaken where a survey was circulated throughout a single private company with 19 sonographers of varying experience participating. The aim was to evaluate the most common method of ICA Doppler insonation used. Results: Results depicted discontinuity among sonographers with 52.6% utilising a constant Doppler angle of 60° and 47.4% using a convenient angle. Eighty percent with >10 years use a convenient angle, 80% with 5 to 10 years use a constant 60°, and sonographers with 1 to 5 years' experience were more evenly split with 43% utilising a constant 60° and 57% using a convenient angle. Discussion: Trends between experience and method were established. Further research with larger numbers to ascertain why sonographers choose a particular method is warranted.