Ultrafast 3D transesophageal echocardiographic (TEE) imaging, combined with 3D echo particle image velocimetry
(ePIV), would be ideal for tracking the complex blood flow patterns in the heart. We are developing a miniature pediatric
matrix TEE transducer that employs micro-beamforming (μBF) and allows high framerate in 3D. In this paper, we assess
the feasibility of 3D ePIV with a high frame rate, small aperture transducer and the influence of the micro-beamforming
technique. We compare the results of 3D ePIV on simulated images using the μBF transducer and an idealized, fully
sampled (FS) matrix transducer.
For the two transducers, we have simulated high-framerate imaging of an 8.4mm diameter artery having a known 4D
velocity field. The simulations were performed in FieldII. 1000 3D volumes, at a rate of 1000 volumes/sec, were created
using a single diverging transmission per volume. The error in the 3D velocity estimation was measured by comparing
the ePIV results of both transducers to the ground truth.
The results on the simulated volumes show that ePIV can estimate the 4D velocity field of the arterial phantom using
these small-aperture transducers suitable for pediatric 3D TEE. The μBF transducer (RMSE 44.0%) achieved
comparable ePIV accuracy to that of the FS transducer (RMSE 42.6%).
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