TY - GEN

T1 - Microbubble tracking with a forward-backward strategy

AU - Taghavi, Iman

AU - Andersen, Sofie Bech

AU - Schou, Mikkel

AU - Nielsen, Michael Bachmann

AU - Sorensen, Charlotte Mehlin

AU - Stuart, Matthias Bo

AU - Jensen, Jorgen Arendt

N1 - Publisher Copyright: © 2022 SPIE. All rights reserved.

PY - 2022

Y1 - 2022

N2 - Microbubble (MB) tracking is an integral part of super-resolution ultrasound imaging by providing sharper images and enabling velocity estimation. Tracking the MBs from the last to the first frame can generate different trajectories than tracking from the first to the last frame, when the next positions of a track depends on its previous positions, e.g., in Kalman-based methods. Our hypothesis is that tracking in a forward-backward manner can increase the overall tracking performance. In simulations, MB positions with a parabolic flow profile were generated inside two tubes. Three different tracking methods, including nearest-neighbor, Kalman, and hierarchical Kalman, were investigated. Using the proposed forward-backward strategy, all estimated velocity profiles for all trackers were improved and were closer to the actual velocity profiles with an improvement between 28% to 40% in the relative standard deviation (RSD) of the velocity values over 10 cross-sections of the tubes. A Sprague Dawley rat kidney was scanned for 10 minutes using a BK5000 scanner and X18L5s transducer, which is a linear array probe with 150 elements. The tracking results from the in vivo experiments showed that the combined image of the forward and backward tracks had 35% additional unique track positions. It showed a clear visual enhancement in the super-resolved velocity map. Overall, the improvement in visual aspects and velocity estimates suggest forward-backward strategy as an upgrade for Kalman-based trackers.

AB - Microbubble (MB) tracking is an integral part of super-resolution ultrasound imaging by providing sharper images and enabling velocity estimation. Tracking the MBs from the last to the first frame can generate different trajectories than tracking from the first to the last frame, when the next positions of a track depends on its previous positions, e.g., in Kalman-based methods. Our hypothesis is that tracking in a forward-backward manner can increase the overall tracking performance. In simulations, MB positions with a parabolic flow profile were generated inside two tubes. Three different tracking methods, including nearest-neighbor, Kalman, and hierarchical Kalman, were investigated. Using the proposed forward-backward strategy, all estimated velocity profiles for all trackers were improved and were closer to the actual velocity profiles with an improvement between 28% to 40% in the relative standard deviation (RSD) of the velocity values over 10 cross-sections of the tubes. A Sprague Dawley rat kidney was scanned for 10 minutes using a BK5000 scanner and X18L5s transducer, which is a linear array probe with 150 elements. The tracking results from the in vivo experiments showed that the combined image of the forward and backward tracks had 35% additional unique track positions. It showed a clear visual enhancement in the super-resolved velocity map. Overall, the improvement in visual aspects and velocity estimates suggest forward-backward strategy as an upgrade for Kalman-based trackers.

KW - Particle tracking

KW - Super-resolution imaging

KW - ultrasound microscopy

KW - velocity estimation

U2 - 10.1117/12.2610753

DO - 10.1117/12.2610753

M3 - Conference article

AN - SCOPUS:85132036747

VL - 12038

JO - Progress in Biomedical Optics and Imaging

JF - Progress in Biomedical Optics and Imaging

SN - 1605-7422

M1 - 120380C

T2 - Medical Imaging 2022: Ultrasonic Imaging and Tomography

Y2 - 21 March 2022 through 27 March 2022

ER -