Three-dimensional aperture-driven photoacoustic tomography (3D-ADPAT)

Area of Science:

• Biomedical imaging
• Photoacoustic computed tomography (PACT)
• Ultrasound technology

Background:

• Photoacoustic computed tomography (PACT) is vital for in vivo biomedical research, merging optical specificity with acoustic penetration.
• Current PACT systems face limitations in ultrasound detection aperture and sensitivity, impacting image contrast, resolution, and depth.

Purpose of the Study:

• To introduce three-dimensional aperture-driven photoacoustic tomography (3D-ADPAT) to overcome PACT's inherent performance trade-offs.
• To enhance image quality, including contrast, resolution, and penetration depth, for advanced biomedical visualization.

Main Methods:

• Developed 3D-ADPAT by integrating a high-numerical-aperture focused ultrasonic transducer (HNA-FUT) with a phase-inverted focusing-equivalent reconstruction (PIFER) algorithm.
• Validated the system through extensive simulations, phantom studies, and in vivo whole-body imaging.

Main Results:

• Achieved approximately a 2.21-fold enhancement in spatial resolution.
• Demonstrated a tenfold increase in contrast-to-noise ratio.
• Successfully visualized deep-seated anatomies and tracked metabolic pathways in vivo.

Conclusions:

• 3D-ADPAT significantly improves spatial resolution and contrast-to-noise ratio in photoacoustic imaging.
• The technology enables detailed visualization of deep tissues and metabolic processes, advancing biomedical research.
• A barrel-shaped array implementation supports dynamic imaging across large fields of view and variable scales.