Ultrasonic Imaging of Deeper Bone Defect Using Virtual Source Synthetic Aperture with Phased Shift Migration: A...

Area of Science:

• Medical Ultrasound
• Biomedical Imaging
• Acoustic Imaging

Background:

• Ultrasound imaging of bone presents challenges due to limited penetration depth and energy.
• Traditional synthetic aperture (SA) techniques offer good lateral resolution but are limited in imaging depth.
• Virtual source (VS) synthetic aperture enables simultaneous multi-element emission, increasing ultrasonic energy for deeper imaging.

Purpose of the Study:

• To develop and validate a novel virtual source phase shift migration (VS-PSM) method for enhanced ultrasound imaging of deeper bone defects.
• To evaluate the performance of VS-PSM in multilayered structures, particularly for visualizing bone defects.
• To compare the imaging quality of VS-PSM against traditional SA and delay-and-sum (DAS) methods.

Main Methods:

• Proposed the virtual source phase shift migration (VS-PSM) method for ultrasonic bone imaging.
• Validated the VS-PSM method using soft tissue and bone phantoms with artificial defects.
• Assessed image quality using contrast-to-noise ratios (CNR) and scatter/defect amplitudes at various depths.

Main Results:

• VS-PSM achieved high-quality imaging of soft tissues with improved scattering amplitude and preserved resolution.
• The phase shift migration (PSM) component demonstrated superior background noise suppression compared to delay-and-sum (DAS).
• VS-PSM significantly improved CNR by an average of 50% for deeper bone defects compared to traditional SA-PSM across different frequencies.

Conclusions:

• The proposed VS-PSM method effectively images deeper bone defects in multilayered structures.
• VS-PSM offers superior contrast-to-noise ratios for bone imaging compared to traditional SA-PSM.
• This technique holds potential for improving the diagnosis of bone diseases using ultrasound.