Enhancing Image Quality of Photoacoustic Tomography Using Sub-Pitch Array Translation Approach: Simulation and...

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Acoustics

Background:

• Photoacoustic tomography (PAT) is a hybrid imaging modality combining optical absorption contrast with ultrasound spatial resolution.
• Achieving high lateral resolution in PAT is crucial for detailed visualization of biological structures.
• Current methods for increasing lateral sampling often involve complex system modifications or specialized transducer arrays.

Purpose of the Study:

• To introduce a practical and convenient method for enhancing lateral discrete array sampling in PAT.
• To improve image quality, specifically lateral resolution and contrast, using a standard linear array transducer.

Main Methods:

• A linear translation-based approach was employed, moving the array transducer by sub-pitch amounts.
• This created augmented RF frame data with denser lateral spatial sampling (λ/2 and λ/4 pitch).
• Reconstruction and comparison of PAT images using simulation and phantom experiments were performed against conventional λ-pitch sampling.

Main Results:

• A 34.48% improvement in lateral resolution (LR) was achieved with λ/2-pitch configuration.
• A maximum of 7-dB improvement in contrast was observed compared to the conventional λ-pitch configuration.
• Both λ/2- and λ/4-pitch configurations demonstrated superior LR and contrast over the λ-pitch configuration.

Conclusions:

• The proposed translation-based method effectively increases lateral sampling for improved PAT image quality.
• λ/2- and λ/4-pitch configurations offer significant enhancements in lateral resolution and contrast.
• This technique provides an easy-to-integrate solution for better image quality in clinical scanners without system complexity increase.