17 results on '"Daniel Razansky"'
Search Results
2. Author Correction: The AP-1 transcription factor Fosl-2 drives cardiac fibrosis and arrhythmias under immunofibrotic conditions
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Mara Stellato, Matthias Dewenter, Michal Rudnik, Amela Hukara, Çagla Özsoy, Florian Renoux, Elena Pachera, Felix Gantenbein, Petra Seebeck, Siim Uhtjaerv, Elena Osto, Daniel Razansky, Karin Klingel, Joerg Henes, Oliver Distler, Przemysław Błyszczuk, and Gabriela Kania
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Medicine (miscellaneous) ,General Agricultural and Biological Sciences ,General Biochemistry, Genetics and Molecular Biology - Published
- 2023
3. Multi-scale optoacoustic molecular imaging of brain diseases
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Daniel Razansky, Jan Klohs, Ruiqing Ni, University of Zurich, and Ni, Ruiqing
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0301 basic medicine ,Multi-spectral optoacoustic tomography (MSOT) ,Computer science ,Neuroimaging ,610 Medicine & health ,Review Article ,Optical imaging ,Photoacoustic Techniques ,03 medical and health sciences ,0302 clinical medicine ,Animals ,2741 Radiology, Nuclear Medicine and Imaging ,Radiology, Nuclear Medicine and imaging ,Brain Neoplasms ,Photoacoustics ,Brain ,11359 Institute for Regenerative Medicine (IREM) ,General Medicine ,Molecular Imaging ,3. Good health ,030104 developmental biology ,Molecular imaging ,Tomography, X-Ray Computed ,Neuroscience ,030217 neurology & neurosurgery ,Optoacoustic imaging - Abstract
The ability to non-invasively visualize endogenous chromophores and exogenous probes and sensors across the entire rodent brain with the high spatial and temporal resolution has empowered optoacoustic imaging modalities with unprecedented capacities for interrogating the brain under physiological and diseased conditions. This has rapidly transformed optoacoustic microscopy (OAM) and multi-spectral optoacoustic tomography (MSOT) into emerging research tools to study animal models of brain diseases. In this review, we describe the principles of optoacoustic imaging and showcase recent technical advances that enable high-resolution real-time brain observations in preclinical models. In addition, advanced molecular probe designs allow for efficient visualization of pathophysiological processes playing a central role in a variety of neurodegenerative diseases, brain tumors, and stroke. We describe outstanding challenges in optoacoustic imaging methodologies and propose a future outlook.
- Published
- 2021
4. Volumetric Optoacoustic Tomography Differentiates Myocardial Remodelling
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Melanie A. Kimm, Daniel Razansky, Ivana Ivankovic, Moritz Wildgruber, Helena Haas, and Xosé Luís Deán-Ben
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Cancer Research ,medicine.medical_specialty ,Cardiac cycle ,business.industry ,Regeneration (biology) ,medicine.disease ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Left coronary artery ,Oncology ,chemistry ,Internal medicine ,medicine.artery ,Occlusion ,medicine ,Cardiology ,Radiology, Nuclear Medicine and imaging ,Myocardial infarction ,business ,Reperfusion injury ,Indocyanine green ,Perfusion - Abstract
Myocardial healing following myocardial infarction (MI) is a complex process that is yet to be fully understood. Clinical attempts in regeneration of the injured myocardium using cardiac stem cells faced major challenges, calling for a better understanding of the processes involved at a more basic level in order to foster translation. We examined the feasibility of volumetric optoacoustic tomography (VOT) in studying healing of the myocardium in different models of MI, including permanent occlusion (PO) of the left coronary artery, temporary occlusion (ischemia-reperfusion—I/R) and infarcted c-kit mutants, a genetic mouse model with impaired cardiac healing. Murine hearts were imaged at 100 Hz frame rate using 800 nm excitation wavelength, corresponding to the peak absorption of indocyanine green (ICG) in plasma and the isosbestic point of haemoglobin. The non-invasive real-time volumetric imaging capabilities of VOT have allowed the detection of significant variations in the pulmonary transit time (PTT), a parameter affected by MI, across different murine models. Upon intravenous injection of ICG, we were able to track alterations in cardiac perfusion in I/R models, which were absent in wild-type (wt) PO or kitW/kitW-v PO mice. The wt-PO and I/R models further exhibited irregularities in their cardiac cycles. Clear differences in the PTT, ICG perfusion and cardiac cycle patterns were identified between the different models and days post MI. Overall, the results highlight the unique capacity of VOT for multi-parametric characterization of morphological and functional changes in murine models of MI.
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- 2020
5. Deep learning optoacoustic tomography with sparse data
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Daniel Razansky, Neda Davoudi, and Xosé Luís Deán-Ben
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0301 basic medicine ,Computer Networks and Communications ,Computer science ,Image quality ,business.industry ,Deep learning ,Image Quantification ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Iterative reconstruction ,Convolutional neural network ,Human-Computer Interaction ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Data acquisition ,Artificial Intelligence ,Temporal resolution ,Computer vision ,Computer Vision and Pattern Recognition ,Tomography ,Artificial intelligence ,business ,030217 neurology & neurosurgery ,Software - Abstract
The rapidly evolving field of optoacoustic (photoacoustic) imaging and tomography is driven by a constant need for better imaging performance in terms of resolution, speed, sensitivity, depth and contrast. In practice, data acquisition strategies commonly involve sub-optimal sampling of the tomographic data, resulting in inevitable performance trade-offs and diminished image quality. We propose a new framework for efficient recovery of image quality from sparse optoacoustic data based on a deep convolutional neural network and demonstrate its performance with whole body mouse imaging in vivo. To generate accurate high-resolution reference images for optimal training, a full-view tomographic scanner capable of attaining superior cross-sectional image quality from living mice was devised. When provided with images reconstructed from substantially undersampled data or limited-view scans, the trained network was capable of enhancing the visibility of arbitrarily oriented structures and restoring the expected image quality. Notably, the network also eliminated some reconstruction artefacts present in reference images rendered from densely sampled data. No comparable gains were achieved when the training was performed with synthetic or phantom data, underlining the importance of training with high-quality in vivo images acquired by full-view scanners. The new method can benefit numerous optoacoustic imaging applications by mitigating common image artefacts, enhancing anatomical contrast and image quantification capacities, accelerating data acquisition and image reconstruction approaches, while also facilitating the development of practical and affordable imaging systems. The suggested approach operates solely on image-domain data and thus can be seamlessly applied to artefactual images reconstructed with other modalities. Optoacoustic imaging can achieve high spatial and temporal resolution but image quality is often compromised by suboptimal data acquisition. A new method employing deep learning to recover high-quality images from sparse or limited-view optoacoustic scans has been developed and demonstrated for whole-body mouse imaging in vivo.
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- 2019
6. Rapid volumetric optoacoustic imaging of neural dynamics across the mouse brain
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Magdalena Anastasia Hutter, Daniel Razansky, Johannes Rebling, Sven Gottschalk, Benedict Mc Larney, Xosé Luís Deán-Ben, Oleksiy Degtyaruk, Shy Shoham, University of Zurich, and Razansky, Daniel
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0301 basic medicine ,Time Factors ,Biomedical Engineering ,10050 Institute of Pharmacology and Toxicology ,2204 Biomedical Engineering ,Medicine (miscellaneous) ,610 Medicine & health ,Bioengineering ,Somatosensory system ,Fluorescence ,Photoacoustic Techniques ,170 Ethics ,03 medical and health sciences ,Imaging, Three-Dimensional ,0302 clinical medicine ,Optical imaging ,Neuroimaging ,In vivo ,Evoked Potentials, Somatosensory ,Microscopy ,1706 Computer Science Applications ,Animals ,Premovement neuronal activity ,10237 Institute of Biomedical Engineering ,1502 Bioengineering ,Chemistry ,Brain ,2701 Medicine (miscellaneous) ,Electric Stimulation ,Computer Science Applications ,Mice, Inbred C57BL ,030104 developmental biology ,1305 Biotechnology ,Calcium ,Female ,Neuroscience ,030217 neurology & neurosurgery ,Ex vivo ,Optoacoustic imaging ,Biotechnology - Abstract
Efforts to scale neuroimaging towards the direct visualization of mammalian brain-wide neuronal activity have faced major challenges. Although high-resolution optical imaging of the whole brain in small animals has been achieved ex vivo, the real-time and direct monitoring of large-scale neuronal activity remains difficult, owing to the performance gap between localized, largely invasive, optical microscopy of rapid, cellular-resolved neuronal activity and whole-brain macroscopy of slow haemodynamics and metabolism. Here, we demonstrate both ex vivo and non-invasive in vivo functional optoacoustic (OA) neuroimaging of mice expressing the genetically encoded calcium indicator GCaMP6f. The approach offers rapid, high-resolution three-dimensional snapshots of whole-brain neuronal activity maps using single OA excitations, and of stimulus-evoked slow haemodynamics and fast calcium activity in the presence of strong haemoglobin background absorption. By providing direct neuroimaging at depths and spatiotemporal resolutions superior to optical fluorescence imaging, functional OA neuroimaging bridges the gap between functional microscopy and whole-brain macroscopy.
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- 2019
7. Accounting for speed of sound variations in volumetric hand-held optoacoustic imaging
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X. Luís Deán-Ben, Ali Ozbek, and Daniel Razansky
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business.industry ,Computer science ,Hand held ,Ultrasound ,Graphics processing unit ,Translation (geometry) ,01 natural sciences ,030218 nuclear medicine & medical imaging ,Electronic, Optical and Magnetic Materials ,Visualization ,010309 optics ,03 medical and health sciences ,0302 clinical medicine ,Speed of sound ,0103 physical sciences ,Computer vision ,Artificial intelligence ,Tomography ,Electrical and Electronic Engineering ,business ,Optoacoustic imaging - Abstract
Hand-held implementations of recently introduced real-time volumetric tomography approaches represent a promising path toward clinical translation of the optoacoustic technology. To this end, rapid acquisition of optoacoustic image data with spherical matrix arrays has attained exquisite visualizations of three-dimensional vascular morphology and function deep in human tissues. Nevertheless, significant reconstruction inaccuracies may arise from speed of sound (SoS) mismatches between the imaged tissue and the coupling medium used to propagate the generated optoacoustic responses toward the ultrasound sensing elements. Herein, we analyze the effects of SoS variations in three-dimensional hand-held tomographic acquisition geometries. An efficient graphics processing unit (GPU)-based reconstruction framework is further proposed to mitigate the SoS-related image quality degradation without compromising the high-frame-rate volumetric imaging performance of the method, essential for real-time visualization during hand-held scans.
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- 2017
8. Transmission–reflection optoacoustic ultrasound (TROPUS) computed tomography of small animals
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Elena Merčep, Daniel Razansky, Joaquin L. Herraiz, and Xosé Luís Deán-Ben
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lcsh:Applied optics. Photonics ,Image quality ,Multispectral image ,02 engineering and technology ,Iterative reconstruction ,01 natural sciences ,Article ,010309 optics ,0103 physical sciences ,lcsh:QC350-467 ,Tomographic reconstruction ,business.industry ,Ultrasound ,lcsh:TA1501-1820 ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,ddc ,3. Good health ,Electronic, Optical and Magnetic Materials ,Ultrasound Tomography ,Tomography ,0210 nano-technology ,business ,lcsh:Optics. Light ,Acoustic attenuation ,Biomedical engineering - Abstract
Rapid progress in the development of multispectral optoacoustic tomography techniques has enabled unprecedented insights into biological dynamics and molecular processes in vivo and noninvasively at penetration and spatiotemporal scales not covered by modern optical microscopy methods. Ultrasound imaging provides highly complementary information on elastic and functional tissue properties and further aids in enhancing optoacoustic image quality. We devised the first hybrid transmission–reflection optoacoustic ultrasound (TROPUS) small animal imaging platform that combines optoacoustic tomography with both reflection- and transmission-mode ultrasound computed tomography. The system features full-view cross-sectional tomographic imaging geometry for concomitant noninvasive mapping of the absorbed optical energy, acoustic reflectivity, speed of sound, and acoustic attenuation in whole live mice with submillimeter resolution and unrivaled image quality. Graphics-processing unit (GPU)-based algorithms employing spatial compounding and bent-ray-tracing iterative reconstruction were further developed to attain real-time rendering of ultrasound tomography images in the full-ring acquisition geometry. In vivo mouse imaging experiments revealed fine details on the organ parenchyma, vascularization, tissue reflectivity, density, and stiffness. We further used the speed of sound maps retrieved by the transmission ultrasound tomography to improve optoacoustic reconstructions via two-compartment modeling. The newly developed synergistic multimodal combination offers unmatched capabilities for imaging multiple tissue properties and biomarkers with high resolution, penetration, and contrast., Hybridized optoacoustic ultrasound computed tomography A three-in-one imaging platform combines the advantages of each individual technique to provide whole body tomographic imaging of small animals. Developed by the group of Daniel Razansky from the University of Zurich and ETH Zurich in Switzerland and collaborators in Germany and Spain, the hybrid platform combines optoacoustic tomography with reflection and transmission mode ultrasonography. By launching ultrasound and laser pulses into tissues, the technique allows the construction of cross-sectional tomographic images that reveal fine details on organ function, tissue vascularization, reflectivity, stiffness and density. As an added value of the hybrid combination, images retrieved by one modality are also used to enhance the reconstruction quality of the other two modalities. The platform could thus be used for probing and quantifying multiple anatomical, functional and molecular properties of tissues in health and disease.
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- 2019
9. Volumetric optoacoustic tomography enables non-invasive in vivo characterization of impaired heart function in hypoxic conditions
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Agnes Görlach, Andreas Petry, Hsiao-Chun Amy Lin, Xosé Luís Deán-Ben, Benjamin Trautz, Daniel Razansky, Ivana Ivankovic, Zuwen Zhang, University of Zurich, and Razansky, Daniel
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0301 basic medicine ,lcsh:Medicine ,10050 Institute of Pharmacology and Toxicology ,Muscle, Smooth, Vascular ,170 Ethics ,Mice ,0302 clinical medicine ,3-D reconstruction ,lcsh:Science ,Hypoxia ,Lung ,Multidisciplinary ,Heart ,Cone-Beam Computed Tomography ,3. Good health ,ddc ,Cardiology ,Tomography ,medicine.medical_specialty ,Hypertension, Pulmonary ,610 Medicine & health ,Pulmonary Artery ,Vascular Remodeling ,Article ,Cardiovascular Physiological Phenomena ,Photoacoustic Techniques ,03 medical and health sciences ,In vivo ,Right ventricular hypertrophy ,Internal medicine ,medicine ,Animals ,Humans ,10237 Institute of Biomedical Engineering ,1000 Multidisciplinary ,Hypertrophy, Right Ventricular ,business.industry ,Photoacoustics ,lcsh:R ,Non invasive ,medicine.disease ,Pulmonary hypertension ,Disease Models, Animal ,030104 developmental biology ,Concomitant ,lcsh:Q ,Histopathology ,business ,030217 neurology & neurosurgery ,Ex vivo - Abstract
Exposure to chronic hypoxia results in pulmonary hypertension characterized by increased vascular resistance and pulmonary vascular remodeling, changes in functional parameters of the pulmonary vasculature, and right ventricular hypertrophy, which can eventually lead to right heart failure. The underlying mechanisms of hypoxia-induced pulmonary hypertension have still not been fully elucidated while no curative treatment is currently available. Commonly employed pre-clinical analytic methods are largely limited to invasive studies interfering with cardiac tissue or otherwise ex vivo functional studies and histopathology. In this work, we suggest volumetric optoacoustic tomography (VOT) for non-invasive assessment of heart function in response to chronic hypoxia. Mice exposed for 3 consecutive weeks to normoxia or chronic hypoxia were imaged in vivo with heart perfusion tracked by VOT using indocyanide green contrast agent at high temporal (100 Hz) and spatial (200 µm) resolutions in 3D. Unequivocal difference in the pulmonary transit time was revealed between the hypoxic and normoxic conditions concomitant with the presence of pulmonary vascular remodeling within hypoxic models. Furthermore, a beat-to-beat analysis of the volumetric image data enabled identifying and characterizing arrhythmic events in mice exposed to chronic hypoxia. The newly introduced non-invasive methodology for analysis of impaired pulmonary vasculature and heart function under chronic hypoxic exposure provides important inputs into development of early diagnosis and treatment strategies in pulmonary hypertension.
- Published
- 2018
10. Simultaneous visualization of tumour oxygenation, neovascularization and contrast agent perfusion by real-time three-dimensional optoacoustic tomography
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Subhamoy Mandal, Xosé Luís Deán-Ben, Daniel Razansky, Vasilis Ntziachristos, and Vladimir Ermolayev
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Indocyanine Green ,Pathology ,medicine.medical_specialty ,media_common.quotation_subject ,Contrast Media ,Mice, Nude ,Mammary Neoplasms, Animal ,01 natural sciences ,030218 nuclear medicine & medical imaging ,Photoacoustic Techniques ,010309 optics ,Neovascularization ,03 medical and health sciences ,Imaging, Three-Dimensional ,Oxygen Consumption ,0302 clinical medicine ,0103 physical sciences ,medicine ,Animals ,Humans ,Contrast (vision) ,Radiology, Nuclear Medicine and imaging ,Tomography ,media_common ,Neuroradiology ,Neovascularization, Pathologic ,business.industry ,Ultrasound ,General Medicine ,Tumour oxygenation ,Perfusion ,Cross-Sectional Studies ,Female ,Radiology ,Molecular imaging ,medicine.symptom ,business ,Neoplasm Transplantation ,Biomedical engineering - Abstract
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. 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. In contrast to methods based on cross-sectional (2D) image acquisition as a basis for 3D rendering, vMSOT has attained concurrent observations from the entire tumour volume at 10 volumetric frames per second. This truly four dimensional imaging performance has enabled here the simultaneous assessment of blood oxygenation gradients and vascularization in solid breast tumours and revealed different types of blood perfusion profiles in-vivo. The newly introduced capacity for high-resolution three-dimensional tracking of fast tumour perfusion suggests vMSOT as a powerful method in preclinical cancer research and theranostics. As the imaging setup can be equally operated in both stationary and handheld mode, the solution is readily translatable for perfusion monitoring in a clinical setting. • vMSOT visualizes 3D anatomic, vascular and functional tumour profiles in real time. • Three types of blood perfusion profiles are revealed in breast tumour model. • The method is readily adaptable to operate in a handheld clinical mode.
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- 2015
11. Optoacoustic monitoring of cutting efficiency and thermal damage during laser ablation
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Erwin Bay, Daniel Razansky, and Alexandre Douplik
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Laser surgery ,Laser ablation ,Materials science ,Pulse (signal processing) ,business.industry ,medicine.medical_treatment ,Transducers ,Pulse duration ,Lasers, Solid-State ,Dermatology ,Laser ,Ablation ,Signal ,law.invention ,Photoacoustic Techniques ,Radiation Injuries, Experimental ,Transducer ,Optics ,law ,medicine ,Animals ,Cattle ,Surgery ,Laser Therapy ,business - Abstract
Successful laser surgery is characterized by a precise cut and effective hemostasis with minimal collateral thermal damage to the adjacent tissues. Consequently, the surgeon needs to control several parameters, such as power, pulse repetition rate, and velocity of movements. In this study we propose utilizing optoacoustics for providing the necessary real-time feedback of cutting efficiency and collateral thermal damage. Laser ablation was performed on a bovine meat slab using a Q-switched Nd-YAG laser (532 nm, 4 kHz, 18 W). Due to the short pulse duration of 7.6 ns, the same laser has also been used for generation of optoacoustic signals. Both the shockwaves, generated due to tissue removal, as well as the normal optoacoustic responses from the surrounding tissue were detected using a single broadband piezoelectric transducer. It has been observed that the rapid reduction in the shockwave amplitude occurs as more material is being removed, indicating decrease in cutting efficiency, whereas gradual decrease in the optoacoustic signal likely corresponds to coagulation around the ablation crater. Further heating of the surrounding tissue leads to carbonization accompanied by a significant shift in the optoacoustic spectra. Our results hold promise for real-time monitoring of cutting efficiency and collateral thermal damage during laser surgery. In practice, this could eventually facilitate development of automatic cut-off mechanisms that will guarantee an optimal tradeoff between cutting and heating while avoiding severe thermal damage to the surrounding tissues.
- Published
- 2013
12. Volumetric real-time multispectral optoacoustic tomography of biomarkers
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Daniel Razansky, Vasilis Ntziachristos, and Andreas Buehler
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Scanner ,Optical contrast ,Computer science ,Multispectral image ,Contrast Media ,Mice, Nude ,02 engineering and technology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,010309 optics ,Mice ,Image reconstruction algorithm ,0103 physical sciences ,Image Processing, Computer-Assisted ,Calibration ,Animals ,Whole Body Imaging ,Computer vision ,Tomography ,Multispectral data ,business.industry ,021001 nanoscience & nanotechnology ,Visualization ,Artificial intelligence ,0210 nano-technology ,business ,Algorithms ,Biomarkers - Abstract
Multispectral optoacoustic tomography (MSOT) has recently been developed to enable visualization of optical contrast and tissue biomarkers, with resolution and speed representative of ultrasound. In the implementation described here, MSOT enables operation in real-time mode by capturing single cross-sectional images in
- Published
- 2011
13. Anatomical and microstructural imaging of angiogenesis
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Fabian Kiessling, Frauke Alves, and Daniel Razansky
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medicine.medical_specialty ,Neovascularization, Pathologic ,medicine.diagnostic_test ,Angiogenesis ,Computer science ,Neovascularization, Physiologic ,Computed tomography ,General Medicine ,Molecular Imaging ,Multiphoton fluorescence microscope ,In vivo ,medicine ,Animals ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiology ,Ex vivo ,Biomedical engineering - Abstract
This article reviews and discusses different options for visualizing the microarchitecture of vessels ex vivo and in vivo with respect to reliability, practicability and availability.The investigation of angiogenesis by standard histological methods, like microvessel density counts, is limited since the three-dimensional (3-D) architecture and the functionality of vessels cannot be considered properly. Coregistration of immunostained images of vessels may be performed but is time consuming and often not sufficiently accurate. Confocal fluorescence microscopy is an alternative, but only enables 3-D stacks of less than 500 nm in thickness. Multiphoton microscopy and other advanced technologies, such as optical coherence tomography and optical frequency domain imaging, provide a deeper view into tissues and allow for in vivo imaging of microvessels, which is a precondition for longitudinal studies. Besides these microscopic techniques, the vascularization in larger tissue samples can be investigated using corrosion casts in combination with scanning electron microscopy, or microcomputed tomography (microCT). Furthermore, recent improvements in microCT technology open up new perspectives for in vivo scans with high resolution and tolerable X-ray doses. Also 3-D contrast-enhanced high-frequency ultrasound has been shown to be sensitive for angiogenic vessels and even distinguishing between mature and immature vessels appears feasible. Microvessel architecture can also be visualized by MRI. Here, T1-weighted angiography techniques after injection of blood pool contrast agents appear preferable. Optoacoustic tomographic imaging has more recently shown promise for high-resolution in vivo mapping of the microvasculature in rodents using intrinsic haemoglobin-based contrast and exogenous contrast agents.
- Published
- 2010
14. Multispectral opto-acoustic tomography of deep-seated fluorescent proteins in vivo
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Daniel Razansky, Rui Ma, Vasilis Ntziachristos, Claudio Vinegoni, Martin Distel, Reinhard W. Köster, and Norbert Perrimon
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business.industry ,ved/biology ,Multispectral image ,ved/biology.organism_classification_rank.species ,Iterative reconstruction ,Fluorescence ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Green fluorescent protein ,Biophotonics ,Optics ,Fluorescence microscope ,Biophysics ,Tomography ,business ,Model organism - Abstract
Fluorescent proteins have become essential reporter molecules for studying life at the cellular and sub-cellular level, re-defining the ways in which we investigate biology. However, because of intense light scattering, most organisms and tissues remain inaccessible to current fluorescence microscopy techniques at depths beyond several hundred micrometres. We describe a multispectral opto-acoustic tomography technique capable of high-resolution visualization of fluorescent proteins deep within highly light-scattering living organisms. The method uses multiwavelength illumination over multiple projections combined with selective-plane opto-acoustic detection for artifact-free data collection. Accurate image reconstruction is enabled by making use of wavelength-dependent light propagation models in tissue. By performing whole-body imaging of two biologically important and optically diffuse model organisms, Drosophila melanogaster pupae and adult zebrafish, we demonstrate the facility to resolve tissue-specific expression of eGFP and mCherrry fluorescent proteins for precise morphological and functional observations in vivo.
- Published
- 2009
15. Erratum: High-frame rate four dimensional optoacoustic tomography enables visualization of cardiovascular dynamics and mouse heart perfusion
- Author
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Xosé Luís Deán-Ben, Steven James Ford, and Daniel Razansky
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Multidisciplinary - Abstract
Functional imaging of mouse models of cardiac health and disease provides a major contribution to our fundamental understanding of the mammalian heart. However, imaging murine hearts presents significant challenges due to their small size and rapid heart rate. Here we demonstrate the feasibility of high-frame-rate, noninvasive optoacoustic imaging of the murine heart. The temporal resolution of 50 three-dimensional frames per second provides functional information at important phases of the cardiac cycle without the use of gating or other motion-reduction methods. Differentiation of the blood oxygenation state in the heart chambers was enabled by exploiting the wavelength dependence of optoacoustic signals. Real-time volumetric tracking of blood perfusion in the cardiac chambers was also evaluated using indocyanine green. Taken together, the newly-discovered capacities offer a unique tool set for in-vivo structural and functional imaging of the whole heart with high spatio-temporal resolution in all three dimensions.
- Published
- 2015
16. Spiral volumetric optoacoustic tomography visualizes multi-scale dynamics in mice
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Thomas Felix Fehm, Steven J. Ford, Daniel Razansky, X. Luís Deán-Ben, and Sven Gottschalk
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Image quality ,Computer science ,Dynamic imaging ,Whole body imaging ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,multi-spectral imaging ,Field of view ,whole-body imaging ,01 natural sciences ,030218 nuclear medicine & medical imaging ,Rendering (computer graphics) ,010309 optics ,03 medical and health sciences ,0302 clinical medicine ,Optics ,Optical coherence tomography ,0103 physical sciences ,medicine ,real-time imaging ,medicine.diagnostic_test ,optoacoustic tomography ,business.industry ,Multi-scale Dynamics ,Multi-spectral Imaging ,Optoacoustic Tomography ,Real-time Imaging ,Whole-body Imaging ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,multi-scale dynamics ,Original Article ,Tomography ,Molecular imaging ,business - Abstract
Imaging dynamics at different temporal and spatial scales is essential for understanding the biological complexity of living organisms, disease state and progression. Optoacoustic imaging has been shown to offer exclusive applicability across multiple scales with excellent optical contrast and high resolution in deep-tissue observations. Yet, efficient visualization of multi-scale dynamics remained difficult with state-of-the-art systems due to inefficient trade-offs between image acquisition time and effective field of view. Herein, we introduce the spiral volumetric optoacoustic tomography technique that provides spectrally enriched high-resolution contrast across multiple spatiotemporal scales. In vivo experiments in mice demonstrate a wide range of dynamic imaging capabilities, from three-dimensional high-frame-rate visualization of moving organs and contrast agent kinetics in selected areas to whole-body longitudinal studies with unprecedented image quality. The newly introduced paradigm shift in imaging of multi-scale dynamics adds to the multifarious advantages provided by the optoacoustic technology for structural, functional and molecular imaging. A rapid-fire laser technique from researchers in Germany can image the entire body of a living mouse in sharp, three-dimensional detail. Optoacoustic imaging uses nanosecond-long laser pulses to briefly heat tissue, creating ultrasonic pressure waves that can be used to non-invasively detect tissue shapes. Switching between fields of view in this technique often requires unsafe acquisition times, but Luis Dean-Ben from the Helmholtz Zentrum Munchen research institute and colleagues have solved this issue with spiral volumetric optoacoustic tomography. In this method, the laser beam follows a spiral trajectory around a live mouse and pressure waves are spotted using a spherical detector with 256 sensitive elements. On-the-fly image rendering could capture dynamic events at millisecond time scales, such as beat-by-beat characterization of heart motion to whole-body studies of the growth of breast cancer tumours.
- Published
- 2016
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17. Adding fifth dimension to optoacoustic imaging: volumetric time-resolved spectrally enriched tomography
- Author
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Xosé Luís Deán-Ben and Daniel Razansky
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Millisecond ,Materials science ,business.industry ,Ultrasound ,Multispectral image ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,01 natural sciences ,Signal ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,010309 optics ,Wavelength ,Optics ,law ,0103 physical sciences ,Tomography ,0210 nano-technology ,business ,biophotonics ,multispectral ,optoacoustic imaging ,photoacoustic tomography ,Ultrashort pulse - Abstract
Xose Luis Dean-Ben and Daniel Razansky at the Technical University of Munich and the Helmholtz Centre Munich have demonstrated three-dimensional multispectral optoacoustic bioimaging in real time. Optoacoustic imaging is a technique wherein a laser beam absorbed by biological tissue induces the creation of a characteristic acoustic signal, which is then detected in the same way as an ultrasound. The technique plays an important role in imaging biological processes in the body due to its excellent optical contrast and high spatial resolution in deep tissues. To detect various substances such as contrast agents in living tissue, scans at multiple wavelengths are required. By employing an ultrafast millisecond timescale laser wavelength tuning along with instantaneous acquisition of volumetric image data, the researchers demonstrated a fully five-dimensional imaging system, thus providing unprecedented flexibility in the mapping of biological processes in-vivo.
- Published
- 2014
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