Wide-field three-dimensional photoacoustic/ultrasound scanner using a two-dimensional matrix transducer array.

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Acoustic Imaging

Background:

• Two-dimensional matrix transducer arrays are optimal for dual-modal 3D photoacoustic (PA)/ultrasound (US) imaging.
• Small footprints of these arrays limit the field-of-view (FOV) to <10 mm × 10 mm, degrading spatial resolution.

Purpose of the Study:

• To develop a dual-modal PA/US imaging system with an enlarged FOV for volumetric imaging.
• To overcome the FOV limitations of conventional 2D matrix transducer arrays.

Main Methods:

• A dual-modal PA/US imaging system was developed using a 2D matrix transducer array and a motorized 2D scanning system.
• Multiple PA volumes were acquired and merged to create a wide-field image.
• In vivo imaging was performed on rat sentinel lymph nodes and bladders.

Main Results:

• The developed system successfully enlarged the FOV to approximately 45 mm × 45 mm.
• Volumetric PA/US imaging was demonstrated in vivo.
• Methylene blue was used as a contrast agent for imaging.

Conclusions:

• The volumetric PA/US imaging technique utilizing a 2D matrix transducer array can significantly expand the FOV.
• This technique is a valuable tool for both narrow-field real-time monitoring and wide-field imaging in preclinical and clinical studies.