Validation of photoacoustic/ultrasound dual imaging in evaluating blood oxygen saturation.

Photoacoustic imaging (PAI) was performed to evaluate oxygen saturation (O) of blood-mimicking phantoms, femoral arteries in beagles, and radial arteries in humans at various O plateaus. The accuracy (root mean square error, RMSE) of PAI O compared with reference O was calculated. In blood-mimicking phantoms, PAI achieved an accuracy of 1.

Visualizing tumor angiogenesis and boundary with polygon-scanning multiscale photoacoustic microscopy.

Recently, we developed an integrated optical-resolution (OR) and acoustic-resolution (AR) PAM, which has multiscale imaging capability using different resolutions. However, limited by the scanning method, a tradeoff exists between the imaging speed and field of view, which impedes its wider applications. Here, we present an improved multiscale PAM which achieves high-speed wide-field imaging based on a homemade polygon scanner.

[Photoacoustic imaging study on spatial structure of microvessels around acupoints in mice with acute myocardial ischemia].

Objective: To observe the changes of microvascular structure of acupoints caused by myocardial ischemia, so as to explore the application of photoacoustic imaging technology in the research of acupoint sensitization.

Methods: Twelve BALB/c mice were randomly divided into normal, sham operation and acute myocardial ischemia (AMI) model groups, with 4 mice in each group. AMI model was established by ligating the left anterior descending coronary artery.

Recovery of photoacoustic images based on accurate ultrasound positioning.

Photoacoustic microscopy is an in vivo imaging technology based on the photoacoustic effect. It is widely used in various biomedical studies because it can provide high-resolution images while being label-free, safe, and harmless to biological tissue. Polygon-scanning is an effective scanning method in photoacoustic microscopy that can realize fast imaging of biological tissue with a large field of view.

Photoacoustic visualization of the fluence rate dependence of photodynamic therapy.

This study investigates the fluence rate effect, an essential modulating mechanism of photodynamic therapy (PDT), by using photoacoustic imaging method. To the best of our knowledge, this is the first time that the fluence rate dependence is investigated at a microscopic scale, as opposed to previous studies that are based on tumor growth/necrosis or animal surviving rate. This micro-scale examination enables subtle biological responses, including the vascular damage and the self-healing response, to be studied.