3-D Vector Flow Estimation With Row-Column-Addressed Arrays.

Area of Science:

• Ultrasound imaging
• Biomedical engineering
• Fluid dynamics

Background:

• Accurate blood flow measurement is crucial for diagnosing cardiovascular diseases.
• Traditional ultrasound methods often struggle with precise 3-D vector flow estimation.

Purpose of the Study:

• To develop and validate a 3-D transverse oscillation (TO) velocity estimator for a 2-D row-column (RC) array.
• To optimize the estimator's parameters using simulations and experimental data for improved accuracy.

Main Methods:

• A parametric simulation study varied flow direction, ensemble length, pulse cycles, steering angles, and apodization profiles.
• The optimized estimator was implemented on a 3-MHz RC array prototype and tested on a flow rig with laminar and pulsating flow phantoms.
• Measurements included M-mode and steered transmit sequences, with 3-D vector flow estimated at various angles.

Main Results:

• The 3-D TO velocity estimator demonstrated low bias and standard deviation for vector components (vx, vy, vz) at a 90° beam-to-flow angle.
• Peak velocity estimation showed a -3% bias.
• Volumetric flow rate estimation yielded a -11.1% bias in laminar flow and -9.7% bias in pulsating flow.

Conclusions:

• The developed 3-D transverse oscillation velocity estimator is effective for accurate 3-D vector flow estimation using a 2-D row-column addressed array.
• The method shows potential for enhanced clinical applications requiring precise blood flow quantification.