Reverberation clutter from subcutaneous tissue layers: simulation and in vivo demonstrations

Area of Science:

• Medical imaging
• Acoustics
• Biomedical engineering

Background:

• Ultrasonic image quality is often degraded by aberration and reverberation.
• While aberration is well-understood, the sources and impact of reverberation remain largely unknown.

Purpose of the Study:

• To investigate the sources and characteristics of reverberation-induced clutter in ultrasonic imaging.
• To understand the role of tissue interfaces and connective tissue in generating reverberation.

Main Methods:

• Simulations of wave propagation in realistic and simplified abdominal wall models.
• Analysis of coherent and diffuse clutter generated by reverberation.
• Observation of clutter magnitude variation with connective tissue angle and density.

Main Results:

• Multi-path scattering from connective tissue/fat interfaces is a dominant source of reverberation clutter.
• Diffuse reverberation clutter is maximal when connective tissue is near normal to the beam and increases with tissue density.
• Thick fascial layers and abdominal compression affect reverberation clutter magnitude and decay.

Conclusions:

• Connective tissue properties significantly influence reverberation clutter.
• Transducer manipulation and beamforming techniques can reduce clutter.
• Simulation findings are supported by in vivo human bladder images.