Laser doppler vibrometer validation of an optical flow motion tracking algorithm

Abstract Background The use of single point laser Doppler vibrometer is well established for evaluating displacement or validation in many applications such as scientific research, defence, manufacturing, and biomedicine with other techniques. In this research, breast shaped fabricated phantoms are used in laser Doppler vibrometery to validate the optical flow motion measuring algorithm used in a mechanical vibration based breast cancer screening system. Methods Three different silicone phantoms were used: healthy; 10 mm inclusion and 20 mm inclusion. The overall goal was to use single point laser Doppler vibrometer data to validate digital image-based elasto-tomography (DIET) motion data from optical flow tracking at frequencies of 16 Hz, 24 Hz, 32 Hz, and 40 Hz. Summary of findings Results show excellent validation with errors less than 6% for healthy phantom, and errors less than 8% for 10 mm inclusion and 20 mm inclusion. Conclusions The overall results from the optical flow motion algorithm used with DIET and a laser Doppler vibrometer at every frequency show the optical flow algorithm captures surface motion of breast shaped silicone phantoms with good accuracy. The optical flow algorithm is thus suitable and robust enough for use in clinical breast screening. Finally, the errors presented quantify explicitly the error of this algorithm verses this laser-based gold standard.