Spatiotemporal Antialiasing in Photoacoustic Computed Tomography

Area of Science:

• Biomedical Imaging
• Medical Physics
• Acoustics

Background:

• Photoacoustic computed tomography (PACT) utilizes full-ring ultrasonic transducer arrays for high-resolution imaging.
• Spatial aliasing artifacts in PACT, arising from unmet Nyquist criteria, remain under-investigated.
• These artifacts degrade image quality even when temporal sampling is adequate.

Purpose of the Study:

• To investigate the sources of spatial aliasing in full-ring PACT geometry.
• To develop and validate a method for mitigating spatial aliasing artifacts in PACT.
• To improve the fidelity of reconstructed PACT images.

Main Methods:

• Spatiotemporal analysis was employed to elucidate the origins of spatial aliasing.
• A combined approach of spatial interpolation and temporal filtering was implemented.
• The proposed method was validated using numerical simulations and in vivo experiments.

Main Results:

• The study successfully identified the root causes of spatial aliasing in PACT.
• The combination of spatial interpolation and temporal filtering demonstrated significant artifact reduction.
• Validated effectiveness of the mitigation technique in both simulated and real-world imaging scenarios.

Conclusions:

• Spatial aliasing is a critical issue affecting full-ring PACT image quality.
• The developed spatial interpolation and temporal filtering technique effectively suppresses aliasing artifacts.
• This method enhances the reliability and diagnostic potential of PACT imaging.