Cardiovascular optoacoustics: From mice to men – A review

Abstract

Imaging has become an indispensable tool in the research and clinical management of cardiovascular disease (CVD). An array of imaging technologies is considered for CVD diagnostics and therapeutic assessment, ranging from ultrasonography, X-ray computed tomography and magnetic resonance imaging to nuclear and optical imaging methods. Each method has different operational characteristics and assesses different aspects of CVD pathophysiology; nevertheless, more information is desirable for achieving a comprehensive view of the disease. Optoacoustic (photoacoustic) imaging is an emerging modality promising to offer novel information on CVD parameters by allowing high-resolution imaging of optical contrast several centimeters deep inside tissue. Implemented with illumination at several wavelengths, multi-spectral optoacoustic tomography (MSOT) in particular, is sensitive to oxygenated and deoxygenated hemoglobin, water and lipids allowing imaging of the vasculature, tissue oxygen saturation and metabolic or inflammatory parameters. Progress with fast-tuning lasers, parallel detection and advanced image reconstruction and data-processing algorithms have recently transformed optoacoustics from a laboratory tool to a promising modality for small animal and clinical imaging. We review progress with optoacoustic CVD imaging, highlight the research and diagnostic potential and current applications and discuss the advantages, limitations and possibilities for integration into clinical routine.

Fluoro‐Photoacoustic Polymeric Renal Reporter for Real‐Time Dual Imaging of Acute Kidney Injury

“…[ 2 ] Despite the fact that many materials have been exploited as contrast agents for PA imaging such as small molecular dyes, [ 3 ] gold nanoparticles, [ 4 ] carbon nanotubes, [ 5 ] and semiconducting polymer nanoparticles, [ 6,7 ] most of them rely on passive accumulation at the disease region to cause signal enhancement relative to healthy tissue. These accumulation agents have been used to detect primary and metastatic tumors, [ 6 ] vascular, [ 8 ] ocular, and lymphatic diseases. [ 9 ] In contrast, activatable PA probes that only emit signal responding to disease biomarkers provide specific and accurate molecular information for disease diagnosis.…”

Real-time spectroscopic photoacoustic/ultrasound (PAUS) scanning with simultaneous fluence compensation and motion correction for quantitative molecular imaging

“…For 25 years, PA imaging has been an active area and is now one of the hottest topics in biomedical optics. PA tomography (PAT) and microscopy (PAM) have numerous diagnostic applications [9][10][11], providing both endogenous [12][13][14][15] and exogenous molecular contrast in structural and functional images [15][16][17]. In particular, PA spectroscopy has produced functional images in the brain and heart [10,[18][19][20], and molecular images using the unique spectra of nanoengineered contrast agents [16,[20][21][22].…”

“…PA tomography (PAT) and microscopy (PAM) have numerous diagnostic applications [9][10][11], providing both endogenous [12][13][14][15] and exogenous molecular contrast in structural and functional images [15][16][17]. In particular, PA spectroscopy has produced functional images in the brain and heart [10,[18][19][20], and molecular images using the unique spectra of nanoengineered contrast agents [16,[20][21][22]. These tools have been extended to clinical breast cancer screening [23][24][25][26], skin lesion diagnosis [27,28], biopsy guidance [29,30], gastrointestinal imaging [31], and tumor metastases and lymph node screening [32].…”

“…PA spectroscopic imaging has been extensively studied in small animal models [10,12,13,16,[20][21][22]51]. However, small animals greatly simplify imaging conditions.…”

A Sparse Deep Learning Approach for Automatic Segmentation of Human Vasculature in Multispectral Optoacoustic Tomography

“…The abundant presence of hemoglobin in the blood renders multispectral optoacoustic tomography (MSOT) an ideal technique for imaging vasculature [1][2][3]. By illuminating tissue at multiple different light wavelengths at the near infrared range (~680-980 nm), MSOT is capable of resolving several tissue chromophores, in particular oxy-(HbO 2 ) and deoxy-hemoglobin (Hb), with a wide range of clinical applications, such as Crohn's disease, systemic sclerosis, breast cancer, brown adipose tissue imaging and thyroid disease [4][5][6][7][8].…”