Development of an anatomical carotid artery flow phantom for the calibration of doppler ultrasound systems

Cardiovascular diseases are responsible for over 50% of all deaths in the UK. Current measurement techniques involve non-invasive Doppler ultrasound imaging of blood velocity, however it is known that measured velocity may be in error by typically 20-60%. This paper presents the development of anatomically correct tissue equivalent vessels for calibration of Doppler ultrasound by particle imaging techniques. Patient specific arterial MRI data is used as the basis for construction of a 3D CAD model. The model was modified to simulate varying degrees of stenosis (narrowing). The arterial geometry is fabricated by Stereolithography to generate investment cast patterns from low melting point alloy. The expendable cores are then used in the construction of optically transparent models for particle image velocimetry (PIV) analysis and for agar models using an acoustically matched tissue mimic material for Doppler ultrasound measurement. Issues concerning the fabrication of models for direct comparison of Doppler and PIV data will be discussed.