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handheld optoacoustic

Angelos Karlas, Josefine Reber, Gael Diot, Dmitry Bozhko, Maria Anastasopoulou, Tareq Ibrahim, Markus Schwaiger, Fabien Hyafil, Vasilis Ntziachristos
Label-free multispectral optoacoustic tomography (MSOT) has recently shown superior performance in visualizing the morphology of human vasculature, especially of smaller vessels, compared to ultrasonography. Herein, we extend these observations towards MSOT interrogation of macrovascular endothelial function. We employed a real-time handheld MSOT scanner to assess flow-mediated dilatation (FMD), a technique used to characterize endothelial function. A data processing scheme was developed to quantify the dimensions and diameter changes of arteries in humans and determine wall distensibility parameters...
July 1, 2017: Biomedical Optics Express
Amalina Binte Ebrahim Attia, Sai Yee Chuah, Daniel Razansky, Chris Jun Hui Ho, Pinky Malempati, U S Dinish, Renzhe Bi, Chit Yaw Fu, Steven J Ford, Joyce Siong-See Lee, Melissa Wee Ping Tan, Malini Olivo, Steven Tien Guan Thng
Currently, imaging technologies that enable dermsurgeons to visualize non-melanoma skin cancers (NMSC) in vivo preoperatively are lacking, resulting in excessive or incomplete removal. Multispectral optoacoustic tomography (MSOT) is a volumetric imaging tool to differentiate tissue chromophores and exogenous contrast agents, based on differences in their spectral signatures and used for high-resolution imaging of functional and molecular contrast at centimeter scale depth. We performed MSOT imaging with two- and three-dimensional handheld scanners on 21 Asian patients with NMSC...
September 2017: Photoacoustics
X L Deán-Ben, S Gottschalk, B Mc Larney, S Shoham, D Razansky
Visualization of dynamic functional and molecular events in an unperturbed in vivo environment is essential for understanding the complex biology of living organisms and of disease state and progression. To this end, optoacoustic (photoacoustic) sensing and imaging have demonstrated the exclusive capacity to maintain excellent optical contrast and high resolution in deep-tissue observations, far beyond the penetration limits of modern microscopy. Yet, the time domain is paramount for the observation and study of complex biological interactions that may be invisible in single snapshots of living systems...
April 18, 2017: Chemical Society Reviews
K Gerrit Held, Michael Jaeger, Jaro Rička, Martin Frenz, H Günhan Akarçay
Spectral optoacoustic (OA) imaging enables spatially-resolved measurement of blood oxygenation levels, based on the distinct optical absorption spectra of oxygenated and de-oxygenated blood. Wavelength-dependent optical attenuation in the bulk tissue, however, distorts the acquired OA spectrum and thus makes quantitative oxygenation measurements challenging. We demonstrate a correction for this spectral distortion without requiring a priori knowledge of the tissue optical properties, using the concept of multiple irradiation sensing: recording the OA signal amplitude of an absorbing structure (e...
June 2016: Photoacoustics
Alexander Dima, Vasilis Ntziachristos
We interrogated the application and imaging features obtained by non-invasive and handheld optoacoustic imaging of the thyroid in-vivo. Optoacoustics can offer complementary contrast to ultrasound, by resolving optical absorption-based and offering speckle-free imaging. In particular we inquired whether vascular structures could be better resolved using optoacoustics. For this reason we developed a compact handheld version of real-time multispectral optoacoustic tomography (MSOT) using a detector adapted to the dimensions and overall geometry of the human neck...
June 2016: Photoacoustics
Adrian Taruttis, Arwin C Timmermans, Philip C Wouters, Marcin Kacprowicz, Gooitzen M van Dam, Vasilis Ntziachristos
Purpose To investigate whether multispectral optoacoustic tomography (MSOT) developed for deep-tissue imaging in humans could enable the clinical assessment of major blood vessels and microvasculature. Materials and Methods The study was approved by the Institutional Review Board of the University Medical Center Groningen (CCMO-NL-43587) and registered in the Dutch National Trial Registry (NTR4125). The authors designed a real-time handheld optoacoustic scanner for human use, based on a concave 8-MHz transducer array, attaining 135° angular coverage...
October 2016: Radiology
Volker Neuschmelting, Neal C Burton, Hannah Lockau, Alexander Urich, Stefan Harmsen, Vasilis Ntziachristos, Moritz F Kircher
A handheld approach to optoacoustic imaging is essential for the clinical translation. The first 2- and 3-dimensional handheld multispectral optoacoustic tomography (MSOT) probes featuring real-time unmixing have recently been developed. Imaging performance of both probes was determined in vitro and in a brain melanoma metastasis mouse model in vivo. T1-weighted MR images were acquired for anatomical reference. The limit of detection of melanoma cells in vitro was significantly lower using the 2D than the 3D probe...
March 2016: Photoacoustics
Steven J Ford, Paul L Bigliardi, Thomas C P Sardella, Alexander Urich, Neal C Burton, Marcin Kacprowicz, Mei Bigliardi, Malini Olivo, Daniel Razansky
Visualizing anatomical and functional features of hair follicle development in their unperturbed environment is key in understanding complex mechanisms of hair pathophysiology and in discovery of novel therapies. Of particular interest is in vivo visualization of the intact pilosebaceous unit, vascularization of the hair bulb, and evaluation of the hair cycle, particularly in humans. Furthermore, noninvasive visualization of the sebaceous glands could offer crucial insight into the pathophysiology of follicle-related diseases and dry or seborrheic skin, in particular by combining in vivo imaging with other phenotyping, genotyping, and microbial analyses...
April 2016: Journal of Investigative Dermatology
Vladimir Ermolayev, Xose Luis Dean-Ben, Subhamoy Mandal, Vasilis Ntziachristos, Daniel Razansky
OBJECTIVES: Intravital imaging within heterogenic solid tumours is important for understanding blood perfusion profiles responsible for establishment of multiple parameters within the tumour mass, such as hypoxic and nutrition gradients, cell viability, proliferation and drug response potentials. METHODS: Herein, we developed a method based on a volumetric multispectral optoacoustic tomography (vMSOT) for cancer imaging in preclinical models and explored its capacity for three-dimensional imaging of anatomic, vascular and functional tumour profiles in real time...
June 2016: European Radiology
X Luís Deán-Ben, Thomas F Fehm, Monika Gostic, Daniel Razansky
Existing mammographic screening solutions are generally associated with several major drawbacks, such as exposure to ionizing radiation or insufficient sensitivity in younger populations with radiographically-dense breast. Even when combined with ultrasound or magnetic resonance imaging, X-Ray mammography may still attain unspecific or false positive results. Thus, development of new breast imaging tools represents a timely medical challenge. We report on a new approach to high-resolution functional and anatomical breast angiography using volumetric hand-held optoacoustic tomography, which employs light intensities safe for human use...
March 2016: Journal of Biophotonics
Xosé Deán-Ben, Thomas Felix Fehm, Daniel Razansky
The exclusive combination of high optical contrast and excellent spatial resolution makes optoacoustics (photoacoustics) ideal for simultaneously attaining anatomical, functional and molecular contrast in deep optically opaque tissues. While enormous potential has been recently demonstrated in the application of optoacoustics for small animal research, vast efforts have also been undertaken in translating this imaging technology into clinical practice. We present here a newly developed optoacoustic tomography approach capable of delivering high resolution and spectrally enriched volumetric images of tissue morphology and function in real time...
2014: Journal of Visualized Experiments: JoVE
Xosé Luís Deán-Ben, Daniel Razansky
Optoacoustic imaging provides a unique combination of high optical contrast and excellent spatial resolution, making it ideal for simultaneous imaging of tissue anatomy as well as functional and molecular contrast in deep optically opaque tissues. We report on development of a portable clinical system for three-dimensional optoacoustic visualization of deep human tissues at video rate. Studies in human volunteers have demonstrated powerful performance in delivering high resolution volumetric multispectral optoacoustic tomography (vMSOT) images of tissue morphology and function, such as blood oxygenation parameters, in real time...
December 2013: Photoacoustics
Michael Jaeger, Jeffrey C Bamber, Martin Frenz
This paper investigates a novel method which allows clutter elimination in deep optoacoustic imaging. Clutter significantly limits imaging depth in clinical optoacoustic imaging, when irradiation optics and ultrasound detector are integrated in a handheld probe for flexible imaging of the human body. Strong optoacoustic transients generated at the irradiation site obscure weak signals from deep inside the tissue, either directly by propagating towards the probe, or via acoustic scattering. In this study we demonstrate that signals of interest can be distinguished from clutter by tagging them at the place of origin with localised tissue vibration induced by the acoustic radiation force in a focused ultrasonic beam...
May 2013: Photoacoustics
Xosé Luís Deán-Ben, Erwin Bay, Daniel Razansky
The breakthrough capacity of optoacoustics for three-dimensional visualization of dynamic events in real time has been recently showcased. Yet, efficient spectral unmixing for functional imaging of entire volumetric regions is significantly challenged by motion artifacts in concurrent acquisitions at multiple wavelengths. Here, we introduce a method for simultaneous acquisition of multispectral volumetric datasets by introducing a microsecond-level delay between excitation laser pulses at different wavelengths...
2014: Scientific Reports
Wolfgang Bost, Robert Lemor, Marc Fournelle
We developed a combined imaging platform allowing optoacoustic and ultrasound imaging based on a low energy laser and a handheld probe. The device is based on a sensitive single element 35-MHz focused transducer, a 2-D piezoscanner and a dual-wavelength switchable Nd:YAG laser. Acoustical detection and optical illumination are confocal for optimization of optoacoustic signal-to-noise ratio. The system allows to scan over a range up to 12 mm ×12 mm in xy-direction with an isotropic lateral resolution of about 90 μm...
September 2014: IEEE Transactions on Medical Imaging
Andreas Buehler, X Luís Deán-Ben, Daniel Razansky, Vasilis Ntziachristos
Optoacoustic (photoacoustic) imaging based on cylindrically focused 1-D transducer arrays comes with powerful characteristics in visualizing optical contrast. Parallel reading of multiple detectors arranged around a tissue cross section enables capturing data for generating images of this plane within micro-seconds. Dedicated small animals scanners and handheld systems using 1-D cylindrically focused ultrasound transducer arrays have demonstrated real-time cross-sectional imaging and high in-plane resolution...
April 2014: IEEE Transactions on Medical Imaging
X Luis Dean-Ben, Ali Ozbek, Daniel Razansky
Optoacoustic tomography provides a unique possibility for ultra-high-speed 3-D imaging by acquiring complete volumetric datasets from interrogation of tissue by a single nanosecond-duration laser pulse. Yet, similarly to ultrasound, optoacoustics is a time-resolved imaging method, thus, fast 3-D imaging implies real-time acquisition and processing of high speed data from hundreds of detectors simultaneously, which presents significant technological challenges. Herein we present a highly efficient graphical processing unit (GPU) framework for real-time reconstruction and visualization of 3-D tomographic optoacoustic data...
November 2013: IEEE Transactions on Medical Imaging
Andreas Buehler, Marcin Kacprowicz, Adrian Taruttis, Vasilis Ntziachristos
Multispectral optoacoustic tomography (MSOT) of functional and molecular contrast has the potential to find broad deployment in clinical practice. We have developed the first handheld MSOT imaging device with fast wavelength tuning achieving a frame rate of 50 Hz. In this Letter, we demonstrate its clinical potential by dynamically resolving multiple disease-relevant tissue chromophores, including oxy-/deoxyhemoglobin, and melanin, in human volunteers.
May 1, 2013: Optics Letters
Alexander Dima, Vasilis Ntziachristos
INTRODUCTION: Optoacoustic (photoacoustic) imaging offers visualization of optical contrast in tissues, within several millimeters to centimeters, with resolutions that are typical of ultrasound imaging. This performance can offer a natural extension to widespread optical microscopy approaches, for applications from small animals to humans. AREAS COVERED: An increasing number of optoacoustic approaches are considered for biomedical imaging. Implementations range from handheld and endoscopic operations to fixed scanner set-ups that can address a wide range of preclinical and clinical needs...
May 2011: Expert Opinion on Medical Diagnostics
Alexander Dima, Vasilis Ntziachristos
The high prevalence of atherosclerosis and the corresponding derived morbidity drives the investigation of novel imaging tools for disease diagnosis and assessment. Multi-spectral optoacoustic tomography (MSOT) can resolve structural, hemodynamic and molecular parameters that relate to cardiovascular disease. Similarly to ultrasound imaging, optoacoustic (photoacoustic) imaging can be implemented as a handheld arrangement which further brings dissemination potential to point of care applications. Correspondingly, we experimentally investigate herein the performance of non-invasive optoacoustic scanning developed for carotid imaging, in phantoms and humans...
October 22, 2012: Optics Express
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