Cardiac 2-D Shear Wave Imaging Using a New Dedicated Clinical Ultrasound System: A Phantom Study

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Biomedical Engineering

Background:

• Shear wave elastography (SWE) is a non-invasive ultrasound technique for assessing tissue stiffness.
• Accurate stiffness measurements are crucial for diagnosing and monitoring various cardiac conditions.
• Evaluating new ultrasound systems and probes is essential for advancing diagnostic capabilities.

Purpose of the Study:

• To evaluate the performance of the MACH 30 ultrasound system for cardiac shear wave imaging.
• To compare the accuracy and homogeneity of stiffness measurements with a previous system (Aixplorer).
• To assess the impact of different probes (linear and phased array) and measurement locations on accuracy.

Main Methods:

• Comparison of MACH 30 and Aixplorer systems using Elasticity QA phantoms.
• Assessment of stiffness measurement accuracy using mean percentage error (MPE).
• Quantile-quantile plots and standard deviation of MPE were used to evaluate distribution agreement and homogeneity.

Main Results:

• The MACH 30 and Aixplorer systems showed similar accuracy for linear probes (MPE 8 ± 14% vs. 20 ± 21%).
• Optimal transthoracic cardiac probe performance was achieved at depths of 4-10 cm (MPE 29.5 ± 25%).
• Measurements outside the optimal depth range or below 20 kPa showed significant differences from the reference.

Conclusions:

• The MACH 30 system with a sectorial probe and cardiac settings provides homogenous stiffness measurements.
• Optimal performance for cardiac shear wave imaging is achieved at depths between 4 and 10 cm.
• These phantom findings support the design of future in vivo cardiac studies.