A beamforming study for implementation of vibro-acoustography with a 1.75-D array transducer

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Acoustics

Background:

• Vibro-acoustography (VA) is an ultrasound imaging method utilizing radiation force from dual-frequency ultrasound beams to induce tissue vibration.
• This vibration generates an acoustic field detected by a hydrophone, enabling image formation.
• Previous implementations utilized 1-D linear-array transducers on clinical ultrasound systems.

Purpose of the Study:

• To investigate vibro-acoustography beamforming and image formation using a 1.75-D array transducer.
• To compare the performance of 1.75-D arrays against traditional 1-D linear arrays for VA imaging.
• To analyze subaperture configurations for optimizing VA imaging with 1.75-D arrays.

Main Methods:

• Numerical simulations were employed to evaluate the point-spread functions of six subaperture configurations for VA imaging.
• Four selected configurations underwent experimental validation using a needle hydrophone.
• Imaging was performed on a urethane breast phantom and an ex vivo human prostate.

Main Results:

• The 1.75-D array transducer demonstrated improved elevation focusing capabilities compared to 1-D linear arrays.
• Analysis revealed enhanced image resolution and contrast in VA imaging with the 1.75-D array.
• Simulations and experimental results confirmed the advantages of the 1.75-D array for VA imaging.

Conclusions:

• Vibro-acoustography utilizing 1.75-D array transducers offers significant advantages over 1-D linear arrays.
• Improved elevation focusing leads to superior image resolution and contrast in VA imaging.
• This advancement holds promise for enhanced diagnostic accuracy in ultrasound-based medical imaging.