“Light in and Sound Out”: Review of Photoacoustic Imaging in Cardiovascular Medicine

Abstract

Photoacoustic imaging (PAI) is one of the most recent additions to the expanding armamentarium of diagnostic imaging technologies. Based on the working principles of optics and ultrasound, PAI provides relatively accurate, differential, and comprehensive information for a variety of physiological and pathological conditions in a real-time fashion. PAI was previously put to use in the field clinical oncology and has only recently been attempted in diseases of the heart and vessels. Notwithstanding the fact that it is still in the pre-clinical stage, PAI, with its important advances, has shown considerable potential to make a significant, transformative leap forward in cardiovascular imaging. The applications of PAI-based techniques in cardiovascular medicine include, but are not limited to, the identification and evaluation of atherosclerotic vulnerable plaque (with or without the use of tissue-specific extraneous contrast), the visualization of clots in different thrombosis-related diseases, the detection of myocardial lesions during catheter ablation of cardiac arrhythmias, the real-time monitoring of blood rheology and hemodynamics, and so on. In this contemporary literature review, we have summarized major applications of different PAI-based techniques for various cardiovascular situations, highlighted key innovations, and their respective clinical feasibilities, and then discussed future perspectives of these versatile methodologies in the practice of cardiovascular imaging. In our view, the unique advantages of PAI render it immensely promising to open up new avenues in the study of cardiovascular diseases.

Photoacoustic imaging for microcirculation

“…PAI offers a potential alternative with its high penetration depth and ability to provide multiparametric information. PAI has been employed for studying the morphology of atherosclerotic plaques and the detection of blood clots 91–95 . Another application of PAI is its ability to aid radiofrequency ablation to treat atrial fibrillation as it can provide reliable imaging of lesions in real time with high resolution and depth 91,96 …”

“…PAI has been employed for studying the morphology of atherosclerotic plaques and the detection of blood clots. [91][92][93][94][95] Another application of PAI is its ability to aid radiofrequency ablation to treat atrial fibrillation as it can provide reliable imaging of lesions in real time with high resolution and depth. 91,96 Lv et al 97 used PAT to image thoracic vessels and whole heart morphology with a spatial resolution of ~200 μm at 10-mm deep in a mouse heart.…”

“…[91][92][93][94][95] Another application of PAI is its ability to aid radiofrequency ablation to treat atrial fibrillation as it can provide reliable imaging of lesions in real time with high resolution and depth. 91,96 Lv et al 97 used PAT to image thoracic vessels and whole heart morphology with a spatial resolution of ~200 μm at 10-mm deep in a mouse heart. They could ascertain areas affected by myocardial infractions and show their progression with time.…”

Photoacoustic imaging of live chicken embryo at multiple developmental stages

“…A low-cost non-invasive imaging modality which can provide both high resolution and good optical contrast may be a suitable option for studying growth of chicken embryo. Photoacoustic imaging (PAI) is an emerging imaging technology which has gained importance in the last two decades due to its advantages of high optical contrast and good acoustic resolution [12][13][14][15][16][17]. PAT is a hybrid imaging modality wherein a nanosecond laser pulse is used to irradiate an object.…”

Enhancement of photoacoustic imaging systems for biomedical applications

“…The drawbacks of above-mentioned optical imaging technologies have led to rapid evolution of photoacoustic imaging (PAI) [19][20][21][22][23][24][25][26][27]. PAI [also called optoacoustic imaging (OAI)] is a hybrid imaging modality that combines the advantages of optical excitation and acoustic detection.…”