High frame rate multi-perspective cardiac ultrasound imaging using phased array probes.

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Cardiovascular Technology

Background:

• Ultrasound (US) imaging is crucial for assessing cardiac disease, but single-probe systems face limitations like restricted field-of-view and anisotropic resolution.
• These inherent physical constraints hinder comprehensive evaluation of cardiac structures, particularly the left ventricle (LV).

Purpose of the Study:

• To develop and evaluate an interleaved multi-perspective 2-D ultrasound imaging system for improved cardiac visualization.
• The aim was to overcome single-probe limitations by acquiring simultaneous data from two phased array probes at a high frame rate.

Main Methods:

• An ex-vivo experiment using a porcine heart was conducted with two phased array probes acquiring parasternal long-axis and apical views.
• Interleaved multi-probe ultrasound data were captured at 170 frames per second (FPS) using diverging wave imaging.
• Image registration and fusion algorithms were employed to align and combine data from the two probes.

Main Results:

• The fused multi-perspective images demonstrated a 34.4% reduction in histogram overlap and a 27.3% increase in contrast-to-noise ratio (CNR) between endocardium and myocardium.
• Image resolution significantly improved, becoming more isotropic (0.35 mm × 0.18 mm) compared to single-perspective imaging (0.59 mm × 0.21 mm).
• Enhanced image details of myocardial tissue were observed, with a 74.4% increase in mean gradient (MG) and a 23.1% increase in entropy.

Conclusions:

• The developed interleaved multi-perspective high frame rate ultrasound system effectively enlarges the field-of-view for cardiac imaging.
• This novel approach significantly improves image contrast and resolution, offering superior visualization of cardiac structures.
• The system shows promise for more accurate diagnosis and assessment of cardiac diseases.