Multispectral optoacoustic tomography of lipid and hemoglobin contrast in human carotid atherosclerosis

Abstract

Several imaging techniques aim at identifying features of carotid plaque instability but come with limitations, such as the use of contrast agents, long examination times and poor portability. Multispectral optoacoustic tomography (MSOT) employs light and sound to resolve lipid and hemoglobin content, both features associated with plaque instability, in a label-free, fast and highly portable way. Herein, 5 patients with carotid atherosclerosis, 5 healthy volunteers and 2 excised plaques, were scanned with handheld MSOT. Spectral unmixing allowed visualization of lipid and hemoglobin content within three ROIs: whole arterial cross-section, plaque and arterial lumen. Calculation of the fat-blood-ratio (FBR) value within the ROIs enabled the differentiation between patients and healthy volunteers (P = 0.001) and between plaque and lumen in patients (P = 0.04). Our results introduce MSOT as a tool for molecular imaging of human carotid atherosclerosis and open new possibilities for research and clinical assessment of carotid plaques.

Evaluation of Tracheal Stenosis in Rabbits Using Multispectral Optoacoustic Tomography

“…Endobronchial OCT, as a new method for airway image in both animal (Mahmood et al, 2006;Lin et al, 2013;Lee et al, 2014) and human (Balakrishnan et al, 2018;Goorsenberg et al, 2018;Kozlowski et al, 2019) may cause airway mucosa injury or aggravate airway stenosis, due to its invasive detection. Furthermore, PAT and MSOT could be an accurate imaging modality for assessment of blood vessel diseases (Yang et al, 2019;Bok et al, 2021;Karlas et al, 2021), highlighting the potential of them as a new tool to evaluate structural and functional information in tubular structures like artery, vein, trachea and bowel. Here we have developed a new non-invasive PAT-based method with high temporal and spatial resolution, which is capable of acquiring structural and functional information of trachea.…”

“…In recent years, tremendous developments in PAT have been achieved, allowing a wide range of applications in preclinical and clinical research, including imaging of thyroid (Dima and Ntziachristos, 2016;Roll et al, 2019), breast (Xu et al, 2019;Yang et al, 2020), tumors (Li et al, 2015;Yamada et al, 2020;Karmacharya et al, 2021;Knorring and Mogensen, 2021;Wang et al, 2021) and skin lesions (Petri et al, 2016;Dahlstrand et al, 2020), as well as functional neuroimaging (Wang et al, 2003;Wu et al, 2019a;Lv et al, 2020). More recently, MSOT is found to be a method with a multitude of possible applications ranging from the small animal studies, to clinical imaging applications (Taruttis et al, 2013;Anne et al, 2020;Karlas et al, 2021), indicating its ability of providing potent structural, functional, and molecular information. Furthermore, PAT and MSOT could be an accurate imaging modality for assessment of blood vessels diseases in vivo (Yang et al, 2019;Bok et al, 2021;Karlas et al, 2021), highlighting the potential of them as a new tool to evaluate structural and functional information in tubular structures like artery, vein, trachea and bowel.…”

“…More recently, MSOT is found to be a method with a multitude of possible applications ranging from the small animal studies, to clinical imaging applications (Taruttis et al, 2013;Anne et al, 2020;Karlas et al, 2021), indicating its ability of providing potent structural, functional, and molecular information. Furthermore, PAT and MSOT could be an accurate imaging modality for assessment of blood vessels diseases in vivo (Yang et al, 2019;Bok et al, 2021;Karlas et al, 2021), highlighting the potential of them as a new tool to evaluate structural and functional information in tubular structures like artery, vein, trachea and bowel.…”

Advanced Ultrasound and Photoacoustic Imaging in Cardiology

“…Please note that the MSOT systems have been given clinical approval, which may enable more opportunities of (pre)clinical studies for a wide range of diagnostic imaging applications in general. Specifically, promising results have been reported recently and demonstrated the great potential of MSOT to visualize vulnerable plaque in carotid artery in patient [ 140 , 141 ], which may accelerate the clinical translation of PA imaging in cardiology.…”

Multi-Aspect Optoacoustic Imaging of Breast Tumors under Chemotherapy with Exogenous and Endogenous Contrasts: Focus on Apoptosis and Hypoxia

“…The chromophores can be endogenous, such as oxygenated (HbO 2 ) and deoxygenated (Hb) hemoglobin, lipids and water, or exogenously administered agents, such as dyes and nanoparticles [17,19]. Based on this principle, MSOT has already been used in several preclinical, translational or even clinical studies, such as: (i) label-free imaging of tissue perfusion/oxygenation in breast cancer, inflammatory bowel diseases, cardiovascular and endocrinology applications, the musculoskeletal system and adipose tissues [17,[20][21][22][23][24][25][26][27][28][29][30] or (ii) imaging of genetically-encoded probes, small-molecule dyes, nanoparticles (e.g., gold and carbon) or photoconvertible proteins [19,[31][32][33].…”