Cost-efficient laser-diode-induced optical-resolution photoacoustic microscopy for two-dimensional/three-dimensional biomedical imaging.

Solid-state laser systems, such as traditional Nd:YAG-based lasers, are commonly used for noninvasive biomedical photoacoustics with nanosecond pulse duration and millijoule pulse energy. However, such lasers are both bulky and expensive for use as a handy tool for clinical applications. As an alternative, a semiconductor light source has the advantages of being compact, inexpensive, and robust.

Noninvasive photoacoustic detecting intraocular foreign bodies with an annular transducer array.

We present a fast photoacoustic imaging system based on an annular transducer array for detection of intraocular foreign bodies. An eight-channel data acquisition system is applied to capture the photoacoustic signals using multiplexing and the total time of data acquisition and transferring is within 3 s. A limited-view filtered back projection algorithm is used to reconstruct the photoacoustic images.

3D-visual laser-diode-based photoacoustic imaging.

We present a 3D-visual laser-diode-based photoacoustic imaging (LD-PAI) system with a pulsed semiconductor laser source, which has the properties of being inexpensive, portable, and durable. The laser source was operated at a wavelength of 905 nm with a repetition rate of 0.8 KHz.

Microwave-induced thermoacoustic scanning CT for high-contrast and noninvasive breast cancer imaging.

A fast thermoacoustic computed tomography system with a multielement linear transducer array was developed to image biological tissues with circular scanning. The spatial resolution of the imaging system and the spectra of the thermoacoustic signals were analyzed. A modified integration backprojection algorithm using velocity potential was employed to recover the direct energy deposition distribution, signal processing methods, and reconstruction algorithms were validated by imaging a phantom.

Detection of foreign body using fast thermoacoustic tomography with a multielement linear transducer array.

Current imaging modalities face challenges in clinical applications due to limitations in resolution or contrast. Microwave-induced thermoacoustic imaging may provide a complementary modality for medical imaging, particularly for detecting foreign objects due to their different absorption of electromagnetic radiation at specific frequencies. A thermoacoustic tomography system with a multielement linear transducer array was developed and used to detect foreign objects in tissue.

High antinoise photoacoustic tomography based on a modified filtered backprojection algorithm with combination wavelet.

How to extract the weak photoacoustic signals from the collected signals with high noise is the key to photoacoustic signal processing. We have developed a modified filtered backprojection algorithm based on combination wavelet for high antinoise photoacoustic tomography. A Q-switched-Nd: yttrium-aluminum-garnet laser operating at 532 nm is used as light source.

Real-time optoacoustic monitoring of vascular damage during photodynamic therapy treatment of tumor.

The optoacoustic technique is a noninvasive imaging method with high spatial resolution. It potentially can be used to monitor anatomical and physiological changes. Photodynamic therapy (PDT)-induced vascular damage is one of the important mechanisms of tumor destruction, and real-time monitoring of vascular changes can have therapeutic significance.