Photoacoustic tomography of monkey brain using virtual point ultrasonic transducers.

Photoacoustic tomography of the mouse cerebral cortex with a high-numerical-aperture-based virtual point detector.

The mouse cerebral cortex was imaged in situ by photoacoustic tomography (PAT). Instead of a flat ultrasonic transducer, a virtual point detector based on a high numerical aperture (NA), positively focused transducer was used. This virtual point detector has a wide omnidirectional acceptance angle, a high sensitivity, and a negligible aperture effect. In addition, the virtual point detector can...

High-numerical-aperture-based virtual point detectors for photoacoustic tomography.

The focal point of a high-numerical-aperture (NA) ultrasonic transducer can be used as a virtual point detector. This virtual point detector detects omnidirectionally over a wide acceptance angle. It also combines a large active transducer surface and a small effective virtual detector size. Thus the sensitivity is high compared with that of a real point detector, and the aperture effect is sma...

Multiple-bandwidth photoacoustic tomography.

Photoacoustic tomography, also referred to as optoacoustic tomography, employs short laser pulses to generate ultrasonic waves in biological tissues. The reconstructed images can be characterized by the convolution of the structure of samples, the laser pulse and the impulse response of the ultrasonic transducer used for detection. Although the laser-induced ultrasonic waves cover a wide spectr...

Photoacoustic tomography of a rat cerebral cortex with a ring-based ultrasonic virtual point detector.

We image a rat cerebral cortex in situ by using a ring-based ultrasonic virtual point detector developed previously. Compared to the image generated by a finite-aperture detector, the image generated by the virtual point detector has a uniformly distributed resolution throughout the imaged area, owing to the lack of aperture effect of the ultrasonic detector. At the periphery of the image, the ...

Photoacoustic Microscopy and Photoacoustic Computed Tomography Using High-frequency Linear Array Ultrasonic Transducers