TY - JOUR

T1 - Super Resolution Ultrasound Imaging Using the Erythrocytes

T2 - II: Velocity Images

AU - Naji, Mostafa Amin

AU - Taghavi, Iman

AU - Schou, Mikkel

AU - Praesius, Sebastian Kazmarek

AU - Hansen, Lauge Naur

AU - Panduro, Nathalie Sarup

AU - Andersen, Sofie Bech

AU - Sogaard, Stinne Byrholdt

AU - Gundlach, Carsten

AU - Kjer, Hans Martin

AU - Tomov, Borislav Gueorguiev

AU - Thomsen, Erik Vilain

AU - Nielsen, Michael Bachmann

AU - Larsen, Niels Bent

AU - Dahl, Anders Bjorholm

AU - Sorensen, Charlotte Mehlin

AU - Jensen, Jorgen Arendt

PY - 2024/6/10

Y1 - 2024/6/10

N2 - Super resolution ultrasound imaging using the erythrocytes (SURE) has recently been introduced. The method uses erythrocytes as targets instead of fragile microbubbles (MBs). The abundance of erythrocyte scatterers makes it possible to acquire SURE data in just a few seconds compared to several minutes in ultrasound localization microscopy (ULM) using MBs. A high number of scatterers can reduce the acquisition time, however, the tracking of uncorrelated and high-density scatterers is quite challenging. This paper hypothesizes that it is possible to detect and track erythrocytes as targets to obtain vascular flow images. A SURE tracking pipeline is used with modules for beamforming, recursive synthetic aperture imaging, motion estimation, echo canceling, peak detection, and recursive nearest neighbor tracker. The SURE tracking pipeline is capable of distinguishing the flow direction and separating tubes of a simulated Field II phantom with 125 to 25 μm wall-to-wall tube distances, as well as a 3D-printed hydrogel micro-flow phantom with 100 to 60 μm wall-to-wall channel distances. The comparison of an in-vivo SURE scan of a Sprague-Dawley rat kidney with ULM and micro-CT scans with voxel sizes of 26.5μm and 5μm demonstrated consistent findings. A microvascular structure composed of 16 vessels exhibited similarities across all imaging modalities. The flow direction and velocity profiles in the SURE scan were found to be concordant with those from ULM.

AB - Super resolution ultrasound imaging using the erythrocytes (SURE) has recently been introduced. The method uses erythrocytes as targets instead of fragile microbubbles (MBs). The abundance of erythrocyte scatterers makes it possible to acquire SURE data in just a few seconds compared to several minutes in ultrasound localization microscopy (ULM) using MBs. A high number of scatterers can reduce the acquisition time, however, the tracking of uncorrelated and high-density scatterers is quite challenging. This paper hypothesizes that it is possible to detect and track erythrocytes as targets to obtain vascular flow images. A SURE tracking pipeline is used with modules for beamforming, recursive synthetic aperture imaging, motion estimation, echo canceling, peak detection, and recursive nearest neighbor tracker. The SURE tracking pipeline is capable of distinguishing the flow direction and separating tubes of a simulated Field II phantom with 125 to 25 μm wall-to-wall tube distances, as well as a 3D-printed hydrogel micro-flow phantom with 100 to 60 μm wall-to-wall channel distances. The comparison of an in-vivo SURE scan of a Sprague-Dawley rat kidney with ULM and micro-CT scans with voxel sizes of 26.5μm and 5μm demonstrated consistent findings. A microvascular structure composed of 16 vessels exhibited similarities across all imaging modalities. The flow direction and velocity profiles in the SURE scan were found to be concordant with those from ULM.

U2 - 10.1109/TUFFC.2024.3411795

DO - 10.1109/TUFFC.2024.3411795

M3 - Journal article

C2 - 38857146

VL - PP

JO - I E E E Transactions on Ultrasonics, Ferroelectrics and Frequency Control

JF - I E E E Transactions on Ultrasonics, Ferroelectrics and Frequency Control

SN - 0885-3010

ER -