TY - CHAP A1 - Klindt, Marco A1 - Prohaska, Steffen A1 - Baum, Daniel A1 - Hege, Hans-Christian ED - Arnold, David ED - Kaminski, Jaime ED - Niccolucci, Franco ED - Stork, Andre T1 - Conveying Archaeological Contexts to Museum Visitors: Case Study Pergamon Exhibition T2 - VAST12: The 13th International Symposium on Virtual Reality, Archaeology and Intelligent Cultural Heritage - Short Papers Y1 - 2012 UR - http://diglib.eg.org/EG/DL/PE/VAST/VAST12S/025-028.pdf U6 - https://doi.org/10.2312/PE/VAST/VAST12S/025-028 SP - 25 EP - 28 PB - Eurographics Association CY - Brighton, UK ER - TY - CHAP A1 - Klindt, Marco A1 - Baum, Daniel A1 - Prohaska, Steffen A1 - Hege, Hans-Christian T1 - iCon.text – a customizable iPad app for kiosk applications in museum exhibitions T2 - EVA 2012 Berlin Y1 - 2012 SP - 150 EP - 155 PB - Gesellschaft zur Förderung angewandter Informatik e.V. CY - Volmerstraße 3, 12489 Berlin ER - TY - JOUR A1 - Kleinfeld, David A1 - Bharioke, Arjun A1 - Blinder, Pablo A1 - Bock, David A1 - Briggman, Kevin A1 - Chklovskii, Dmitri A1 - Denk, Winfried A1 - Helmstaedter, Moritz A1 - Kaufhold, John A1 - Lee, Wei-Chung A1 - Meyer, Hanno A1 - Micheva, Kristina A1 - Oberlaender, Marcel A1 - Prohaska, Steffen A1 - Reid, R. A1 - Smith, Stephen A1 - Takemura, Shinya A1 - Tsai, Philbert A1 - Sakmann, Bert T1 - Large-scale automated histology in the pursuit of connectomes JF - Journal of Neuroscience Y1 - 2011 UR - http://www.zib.de/prohaska/docs/Kleinfeld_JNS_Connectomes_2011.pdf U6 - https://doi.org/10.1523/JNEUROSCI.4077-11.2011 VL - 31 IS - 45 SP - 16125 EP - 16138 ER - TY - JOUR A1 - Rigort, Alexander A1 - Günther, David A1 - Hegerl, Reiner A1 - Baum, Daniel A1 - Weber, Britta A1 - Prohaska, Steffen A1 - Medalia, Ohad A1 - Baumeister, Wolfgang A1 - Hege, Hans-Christian T1 - Automated segmentation of electron tomograms for a quantitative description of actin filament networks JF - Journal of Structural Biology Y1 - 2012 U6 - https://doi.org/10.1016/j.jsb.2011.08.012 VL - 177 SP - 135 EP - 144 ER - TY - CHAP A1 - Homberg, Ulrike A1 - Baum, Daniel A1 - Prohaska, Steffen A1 - Kalbe, Ute A1 - Witt, Karl Josef T1 - Automatic Extraction and Analysis of Realistic Pore Structures from µCT Data for Pore Space Characterization of Graded Soil T2 - Proceedings of the 6th International Conference on Scour and Erosion (ICSE-6) Y1 - 2012 SP - 345 EP - 352 ER - TY - JOUR A1 - Weber, Britta A1 - Greenan, Garrett A1 - Prohaska, Steffen A1 - Baum, Daniel A1 - Hege, Hans-Christian A1 - Müller-Reichert, Thomas A1 - Hyman, Anthony A1 - Verbavatz, Jean-Marc T1 - Automated tracing of microtubules in electron tomograms of plastic embedded samples of Caenorhabditis elegans embryos JF - Journal of Structural Biology Y1 - 2012 UR - http://www.sciencedirect.com/science/article/pii/S1047847711003509 U6 - https://doi.org/10.1016/j.jsb.2011.12.004 VL - 178 IS - 2 SP - 129 EP - 138 ER - TY - CHAP A1 - Ehrig, Karsten A1 - Goebbels, Jürgen A1 - Meinel, Dietmar A1 - Paetsch, Olaf A1 - Prohaska, Steffen A1 - Zobel, Valentin T1 - Comparison of Crack Detection Methods for Analyzing Damage Processes in Concrete with Computed Tomography T2 - International Symposium on Digital Industrial Radiology and Computed Tomography Y1 - 2011 ER - TY - CHAP A1 - Binner, Richard A1 - Homberg, Ulrike A1 - Prohaska, Steffen A1 - Kalbe, Ute A1 - Witt, Karl Josef T1 - Identification of Descriptive Parameters of the Soil Pore Structure using Experiments and CT Data T2 - Proceedings of the 5th International Conference on Scour and Erosion (ICSE-5) Y1 - 2010 SP - 397 EP - 407 PB - American Society of Civil Engineers (ASCE) ER - TY - JOUR A1 - Lindow, Norbert A1 - Baum, Daniel A1 - Prohaska, Steffen A1 - Hege, Hans-Christian T1 - Accelerated Visualization of Dynamic Molecular Surfaces JF - Comput. Graph. Forum Y1 - 2010 U6 - https://doi.org/10.1111/j.1467-8659.2009.01693.x VL - 29 SP - 943 EP - 952 ER - TY - CHAP A1 - Reininghaus, Jan A1 - Günther, David A1 - Hotz, Ingrid A1 - Prohaska, Steffen A1 - Hege, Hans-Christian T1 - TADD: A Computational Framework for Data Analysis Using Discrete Morse Theory T2 - Mathematical Software - ICMS 2010 Y1 - 2010 U6 - https://doi.org/10.1007/978-3-642-15582-6_35 VL - 6327 SP - 198 EP - 208 PB - Springer ER - TY - JOUR A1 - Kuß, Anja A1 - Gensel, Maria A1 - Meyer, Björn A1 - Dercksen, Vincent J. A1 - Prohaska, Steffen T1 - Effective Techniques to Visualize Filament-Surface Relationships JF - Comput. Graph. Forum Y1 - 2010 VL - 29 SP - 1003 EP - 1012 ER - TY - GEN A1 - Günther, David A1 - Reininghaus, Jan A1 - Prohaska, Steffen A1 - Weinkauf, Tino A1 - Hege, Hans-Christian ED - Peikert, Ronny ED - Hauser, Helwig ED - Carr, Hamish T1 - Efficient Computation of a Hierarchy of Discrete 3D Gradient Vector Fields T2 - Topological Methods in Data Analysis and Visualization II Y1 - 2012 U6 - https://doi.org/10.1007/978-3-642-23175-9_2 SP - 15 EP - 29 PB - Springer ER - TY - CHAP A1 - Homberg, Ulrike A1 - Baum, Daniel A1 - Prohaska, Steffen ED - Mücklich, Frank ED - Slussallek, Philipp ED - Schladitz, Katja T1 - Describing and Analyzing the Dual Structures of Porous Media T2 - Proc. 3D-Microstructure Meeting Y1 - 2011 SP - 24 EP - 25 ER - TY - CHAP A1 - Weber, Britta A1 - Möller, Marit A1 - Verbavatz, Jean-Marc A1 - Baum, Daniel A1 - Hege, Hans-Christian A1 - Prohaska, Steffen T1 - Fast Tracing of Microtubule Centerlines in Electron Tomograms T2 - BioVis 2011 Abstracts, 1st IEEE Symposium on Biological Data Visualization Y1 - 2011 ER - TY - CHAP A1 - Clasen, Malte A1 - Prohaska, Steffen T1 - Image-Error-Based Level of Detail for Landscape Visualization T2 - Proc. VMV 2010 Y1 - 2010 SP - 267 EP - 274 ER - TY - JOUR A1 - Ziegler, Alexander A1 - Ogurreck, Malte A1 - Steinke, Thomas A1 - Beckmann, Felix A1 - Prohaska, Steffen A1 - Ziegler, Andreas T1 - Opportunities and challenges for digital morphology JF - Biology Direct Y1 - 2010 U6 - https://doi.org/10.1186/1745-6150-5-45 VL - 5 IS - 1 SP - 45 ER - TY - CHAP A1 - Homberg, Ulrike A1 - Binner, Richard A1 - Prohaska, Steffen A1 - Dercksen, Vincent J. A1 - Kuß, Anja A1 - Kalbe, Ute T1 - Determining Geometric Grain Structure from X-Ray Micro-Tomograms of Gradated Soil T2 - Workshop Internal Erosion Y1 - 2009 VL - 21 SP - 37 EP - 52 ER - TY - CHAP A1 - Mehlhorn, Tobias A1 - Prohaska, Steffen A1 - Homberg, Ulrike A1 - Slowik, Volker T1 - Modelling and Analysis of Particle and Pore Structures in Soils T2 - Workshop Internal Erosion Y1 - 2009 VL - 21 SP - 53 EP - 60 ER - TY - CHAP A1 - Semar, Olivier A1 - Binner, Richard A1 - Homberg, Ulrike A1 - Kalbe, Ute A1 - Mehlhorn, Tobias A1 - Prohaska, Steffen A1 - Slowik, Volker A1 - Witt, Karl Josef T1 - Conditions for Suffosive Erosion Phemomena in Soils – Concept and Approach T2 - Workshop Internal Erosion Y1 - 2009 VL - 21 SP - 29 EP - 35 ER - TY - JOUR A1 - Petz, Christoph A1 - Kasten, Jens A1 - Prohaska, Steffen A1 - Hege, Hans-Christian T1 - Hierarchical Vortex Regions in Swirling Flow JF - Computer Graphics Forum Y1 - 2009 VL - 28 IS - 3 SP - 863 EP - 870 ER - TY - CHAP A1 - Dercksen, Vincent J. A1 - Weber, Britta A1 - Günther, David A1 - Oberlaender, Marcel A1 - Prohaska, Steffen A1 - Hege, Hans-Christian T1 - Automatic alignment of stacks of filament data T2 - Proc. IEEE International Symposium on Biomedical Imaging Y1 - 2009 SP - 971 EP - 974 PB - IEEE press CY - Boston, USA ER - TY - CHAP A1 - Rosanwo, Olufemi A1 - Petz, Christoph A1 - Prohaska, Steffen A1 - Hotz, Ingrid A1 - Hege, Hans-Christian ED - Eades, Peter ED - Ertl, Thomas ED - Shen, Han-Wei T1 - Dual Streamline Seeding T2 - Proceedings of the IEEE Pacific Visualization Symposium Y1 - 2009 SP - 9 EP - 16 CY - Beijing, China ER - TY - CHAP A1 - Kuß, Anja A1 - Prohaska, Steffen A1 - Meyer, Björn A1 - Rybak, Jürgen A1 - Hege, Hans-Christian T1 - Ontology-Based Visualization of Hierarchical Neuroanatomical Structures T2 - Proceedings of the Eurographics Workshop on Visual Computing for Biomedicine VCBM 2008 Y1 - 2008 SP - 177 EP - 184 ER - TY - CHAP A1 - Petz, Christoph A1 - Prohaska, Steffen A1 - Goubergrits, Leonid A1 - Kertzscher, Ulrich A1 - Hege, Hans-Christian T1 - Near-Wall Flow Visualization in Flattened Surface Neighborhoods T2 - Proc. Simulation and Visualization 2008 Y1 - 2008 UR - http://www.simvis.org/Tagung2008/sv-proceedings.html SP - 93 EP - 105 CY - Magdeburg, Germany ER - TY - JOUR A1 - Sahner, Jan A1 - Weber, Britta A1 - Lamecker, Hans A1 - Prohaska, Steffen T1 - Extraction of feature Lines on surface meshes based on discrete Morse theory JF - Computer Graphics Forum Y1 - 2008 U6 - https://doi.org/10.1111/j.1467-8659.2008.01202.x VL - 27 IS - 3 SP - 735 EP - 742 CY - Eindhoven, Netherlands ER - TY - CHAP A1 - Kuß, Anja A1 - Prohaska, Steffen A1 - Rybak, Jürgen T1 - Using Ontologies for the Visualization of Hierarchical Neuroanatomical Structures T2 - Frontiers in Neuroinformatics. Conference Abstract: 2nd INCF Congress of Neuroinformatics Y1 - 2009 U6 - https://doi.org/10.3389/conf.neuro.11.2009.08.017 ER - TY - JOUR A1 - Saparin, Peter A1 - Thomsen, Jesper A1 - Prohaska, Steffen A1 - Zaikin, Alexei A1 - Kurths, Jürgen A1 - Hege, Hans-Christian A1 - Gowin, Wolfgang T1 - Quantification of spatial structure of human proximal tibial bone biopsies using 3D measures of complexity JF - Acta Astronautica Y1 - 2005 U6 - https://doi.org/10.1016/j.actaastro.2005.01.007 VL - 56 IS - 9-12 SP - 820 EP - 830 ER - TY - JOUR A1 - Prohaska, Steffen A1 - Dreher, Matthew A1 - Dewhirst, Mark A1 - Chilkoti, Ashutosh A1 - Pries, Axel T1 - 3-D reconstruction of tumor vascular networks JF - J. Vas. Res. Y1 - 2004 VL - 41 SP - 463 ER - TY - CHAP A1 - Prohaska, Steffen A1 - Hutanu, Andrei A1 - Kähler, Ralf A1 - Hege, Hans-Christian T1 - Interactive exploration of large remote micro-CT scans T2 - Proc. IEEE Visualization 2004 Y1 - 2004 U6 - https://doi.org/10.1109/VIS.2004.51 SP - 345 EP - 352 CY - Austin, Texas ER - TY - CHAP A1 - Fouard, Céline A1 - Malandain, Grégoire A1 - Prohaska, Steffen A1 - Westerhoff, Malte A1 - Cassot, Francis A1 - Mazel, Christophe A1 - Asselot, Didier A1 - Marc-Vergnes, Jean-Pierre T1 - Skeletonization by blocks for large 3D datasets: Application to brain microcirculation T2 - IEEE International Symposium on Biomedical Imaging: From Nano to Macro (ISBI'04) Y1 - 2004 U6 - https://doi.org/10.1109/ISBI.2004.1398481 SP - 89 EP - 92 CY - Arlington, Virginia ER - TY - CHAP A1 - Fouard, Céline A1 - Malandain, Grégoire A1 - Prohaska, Steffen A1 - Westerhoff, Malte A1 - Cassot, Francis A1 - Mazel, Christophe A1 - Asselot, Didier A1 - Marc-Vergnes, Jean-Pierre T1 - Squelettisation par blocs pour des grands volumes de données 3D T2 - Reconnaissance des Formes et Intelligence Artificielle (RFIA 2004) Y1 - 2004 CY - Toulouse, France ER - TY - JOUR A1 - Hutanu, Andrei A1 - Allen, Gabrielle A1 - Beck, Stephen A1 - Holub, Petr A1 - Kaiser, Hartmut A1 - Kulshrestha, Archit A1 - Liska, Milos A1 - MacLaren, Jon A1 - Matyska, Ludek A1 - Paruchuri, Ravi A1 - Prohaska, Steffen A1 - Seidel, Edward A1 - Ullmer, Brygg A1 - Venkataraman, Shalini T1 - Distributed and collaborative visualization of large data sets using high-speed networks JF - Future Generation Comp. Syst Y1 - 2006 U6 - https://doi.org/10.1016/j.future.2006.03.026 VL - 22(8) SP - 1004 EP - 1010 ER - TY - JOUR A1 - Hege, Hans-Christian A1 - Weinkauf, Tino A1 - Prohaska, Steffen A1 - Hutanu, Andrei T1 - Towards distributed visualization and analysis of large flow data JF - JSME International Journal, Series B Y1 - 2005 VL - 48 (2) SP - 241 EP - 246 ER - TY - CHAP A1 - Dercksen, Vincent J. A1 - Prohaska, Steffen A1 - Hege, Hans-Christian T1 - Fast cross-sectional display of large data sets T2 - IAPR Conference on Machine Vision Applications Y1 - 2005 SP - 336 EP - 339 CY - Tsukuba, Japan ER - TY - CHAP A1 - Prohaska, Steffen T1 - Interaktive Visualisierung und Datenanalyse: Herausforderungen durch wachsende Datenmengen T2 - Kartographische Schriften Y1 - 2006 VL - 10 SP - 103 EP - 110 ER - TY - CHAP A1 - Kähler, Ralf A1 - Prohaska, Steffen A1 - Hutanu, Andrei A1 - Hege, Hans-Christian T1 - Visualization of time-dependent remote adaptive mesh refinement data T2 - Proc. IEEE Visualization 2005 Y1 - 2005 U6 - https://doi.org/10.1109/VISUAL.2005.1532793 SP - 175 EP - 182 CY - Minneapolis, USA ER - TY - JOUR A1 - Thomsen, Jesper A1 - Laib, Andreas A1 - Koller, Bruno A1 - Prohaska, Steffen A1 - Mosekilde, L. A1 - Gowin, Wolfgang T1 - Stereological measures of trabecular bone structure: Comparison of 3D micro computed tomography with 2D histological sections in human proximal tibial bone biopsies JF - Journal of Microscopy Y1 - 2005 VL - 218 SP - 171 EP - 179 ER - TY - CHAP A1 - Prohaska, Steffen A1 - Hutanu, Andrei T1 - Remote data access for interactive visualization T2 - 13th Annual Mardi Gras Conference: Frontiers of Grid Applications and Technologies Y1 - 2005 SP - 17 EP - 22 ER - TY - JOUR A1 - Fouard, Céline A1 - Malandain, Grégoire A1 - Prohaska, Steffen A1 - Westerhoff, Malte T1 - Blockwise processing applied to brain micro-vascular network study JF - IEEE Transactions on Medical Imaging Y1 - 2006 U6 - https://doi.org/10.1109/TMI.2006.880670 VL - 25 IS - 10 SP - 1319 EP - 1328 ER - TY - JOUR A1 - Zaikin, Alexei A1 - Saparin, Peter A1 - Kurths, Jürgen A1 - Prohaska, Steffen A1 - Gowin, Wolfgang T1 - Modeling resorption in 2D-CT and 3D μ-CT bone images JF - Int. J. of Bif. and Chaos Y1 - 2005 VL - 15(9) SP - 2995 EP - 3009 ER - TY - JOUR A1 - Weber, Britta A1 - Tranfield, Erin M. A1 - Höög, Johanna L. A1 - Baum, Daniel A1 - Antony, Claude A1 - Hyman, Tony A1 - Verbavatz, Jean-Marc A1 - Prohaska, Steffen T1 - Automated stitching of microtubule centerlines across serial electron tomograms JF - PLoS ONE Y1 - 2014 U6 - https://doi.org/10.1371/journal.pone.0113222 SP - e113222 ER - TY - GEN A1 - Redemann, Stefanie A1 - Weber, Britta A1 - Möller, Marit A1 - Verbavatz, Jean-Marc A1 - Hyman, Anthony A1 - Baum, Daniel A1 - Prohaska, Steffen A1 - Müller-Reichert, Thomas T1 - The Segmentation of Microtubules in Electron Tomograms Using Amira T2 - Mitosis: Methods and Protocols Y1 - 2014 U6 - https://doi.org/10.1007/978-1-4939-0329-0_12 SP - 261 EP - 278 PB - Springer ER - TY - GEN A1 - Costa, Marta A1 - Ostrovsky, Aaron D. A1 - Manton, James D. A1 - Prohaska, Steffen A1 - Jefferis, Gregory S.X.E. T1 - NBLAST: Rapid, sensitive comparison of neuronal structure and construction of neuron family databases T2 - bioRxiv preprint Y1 - 2015 U6 - https://doi.org/10.1101/006346 ER - TY - GEN A1 - Hoerth, Rebecca M. A1 - Baum, Daniel A1 - Knötel, David A1 - Prohaska, Steffen A1 - Willie, Bettina M. A1 - Duda, Georg A1 - Hege, Hans-Christian A1 - Fratzl, Peter A1 - Wagermaier, Wolfgang T1 - Registering 2D and 3D Imaging Data of Bone during Healing N2 - Purpose/Aims of the Study: Bone’s hierarchical structure can be visualized using a variety of methods. Many techniques, such as light and electron microscopy generate two-dimensional (2D) images, while micro computed tomography (μCT) allows a direct representation of the three-dimensional (3D) structure. In addition, different methods provide complementary structural information, such as the arrangement of organic or inorganic compounds. The overall aim of the present study is to answer bone research questions by linking information of different 2D and 3D imaging techniques. A great challenge in combining different methods arises from the fact that they usually reflect different characteristics of the real structure. Materials and Methods: We investigated bone during healing by means of μCT and a couple of 2D methods. Backscattered electron images were used to qualitatively evaluate the tissue’s calcium content and served as a position map for other experimental data. Nanoindentation and X-ray scattering experiments were performed to visualize mechanical and structural properties. Results: We present an approach for the registration of 2D data in a 3D μCT reference frame, where scanning electron microscopies serve as a methodic link. Backscattered electron images are perfectly suited for registration into μCT reference frames, since both show structures based on the same physical principles. We introduce specific registration tools that have been developed to perform the registration process in a semi-automatic way. Conclusions: By applying this routine, we were able to exactly locate structural information (e.g. mineral particle properties) in the 3D bone volume. In bone healing studies this will help to better understand basic formation, remodeling and mineralization processes. T3 - ZIB-Report - 15-01 Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-53426 SN - 1438-0064 ER - TY - JOUR A1 - Hoerth, Rebecca M. A1 - Baum, Daniel A1 - Knötel, David A1 - Prohaska, Steffen A1 - Willie, Bettina M. A1 - Duda, Georg A1 - Hege, Hans-Christian A1 - Fratzl, Peter A1 - Wagermaier, Wolfgang T1 - Registering 2D and 3D Imaging Data of Bone during Healing JF - Connective Tissue Research Y1 - 2015 U6 - https://doi.org/10.3109/03008207.2015.1005210 VL - 56 IS - 2 SP - 133 EP - 143 PB - Taylor & Francis ER - TY - GEN A1 - Weber, Britta A1 - Tranfield, Erin M. A1 - Höög, Johanna L. A1 - Baum, Daniel A1 - Antony, Claude A1 - Hyman, Tony A1 - Verbavatz, Jean-Marc A1 - Prohaska, Steffen T1 - Automated stitching of microtubule centerlines across serial electron tomograms N2 - Tracing microtubule centerlines in serial section electron tomography requires microtubules to be stitched across sections, that is lines from different sections need to be aligned, endpoints need to be matched at section boundaries to establish a correspondence between neighboring sections, and corresponding lines need to be connected across multiple sections. We present computational methods for these tasks: 1) An initial alignment is computed using a distance compatibility graph. 2) A fine alignment is then computed with a probabilistic variant of the iterative closest points algorithm, which we extended to handle the orientation of lines by introducing a periodic random variable to the probabilistic formulation. 3) Endpoint correspondence is established by formulating a matching problem in terms of a Markov random field and computing the best matching with belief propagation. Belief propagation is not generally guaranteed to converge to a minimum. We show how convergence can be achieved, nonetheless, with minimal manual input. In addition to stitching microtubule centerlines, the correspondence is also applied to transform and merge the electron tomograms. We applied the proposed methods to samples from the mitotic spindle in C. elegans, the meiotic spindle in X. laevis, and sub-pellicular microtubule arrays in T. brucei. The methods were able to stitch microtubules across section boundaries in good agreement with experts’ opinions for the spindle samples. Results, however, were not satisfactory for the microtubule arrays. For certain experiments, such as an analysis of the spindle, the proposed methods can replace manual expert tracing and thus enable the analysis of microtubules over long distances with reasonable manual effort. T3 - ZIB-Report - 14-41 KW - electron tomography KW - microtubules KW - serial sectioning KW - image analysis KW - geometry reconstruction KW - image and geometry alignment KW - point correspondence Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-52958 SN - 1438-0064 ER - TY - GEN A1 - Kaplan, Bernhard A1 - Laufer, Jan A1 - Prohaska, Steffen A1 - Buchmann, Jens T1 - Monte-Carlo-based inversion scheme for 3D quantitative photoacoustic tomography N2 - The goal of quantitative photoacoustic tomography (qPAT) is to recover maps of the chromophore distributions from multiwavelength images of the initial pressure. Model-based inversions that incorporate the physical processes underlying the photoacoustic (PA) signal generation represent a promising approach. Monte-Carlo models of the light transport are computationally expensive, but provide accurate fluence distributions predictions, especially in the ballistic and quasi-ballistic regimes. Here, we focus on the inverse problem of 3D qPAT of blood oxygenation and investigate the application of the Monte-Carlo method in a model-based inversion scheme. A forward model of the light transport based on the MCX simulator and acoustic propagation modeled by the k-Wave toolbox was used to generate a PA image data set acquired in a tissue phantom over a planar detection geometry. The combination of the optical and acoustic models is shown to account for limited-view artifacts. In addition, the errors in the fluence due to, for example, partial volume artifacts and absorbers immediately adjacent to the region of interest are investigated. To accomplish large-scale inversions in 3D, the number of degrees of freedom is reduced by applying image segmentation to the initial pressure distribution to extract a limited number of regions with homogeneous optical parameters. The absorber concentration in the tissue phantom was estimated using a coordinate descent parameter search based on the comparison between measured and modeled PA spectra. The estimated relative concentrations using this approach lie within 5 % compared to the known concentrations. Finally, we discuss the feasibility of this approach to recover the blood oxygenation from experimental data. T3 - ZIB-Report - 17-04 KW - quantitative photoacoustic tomography KW - model-based inversion KW - oxygen saturation KW - chromophore concentration KW - photoacoustic imaging KW - Monte Carlo methods for light transport KW - boundary conditions KW - coordinate search Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-62318 SN - 1438-0064 ER - TY - CHAP A1 - Kaplan, Bernhard A1 - Buchmann, Jens A1 - Prohaska, Steffen A1 - Laufer, Jan T1 - Monte-Carlo-based inversion scheme for 3D quantitative photoacoustic tomography T2 - Proc. of SPIE, Photons Plus Ultrasound: Imaging and Sensing 2017 N2 - The goal of quantitative photoacoustic tomography (qPAT) is to recover maps of the chromophore distributions from multiwavelength images of the initial pressure. Model-based inversions that incorporate the physical processes underlying the photoacoustic (PA) signal generation represent a promising approach. Monte-Carlo models of the light transport are computationally expensive, but provide accurate fluence distributions predictions, especially in the ballistic and quasi-ballistic regimes. Here, we focus on the inverse problem of 3D qPAT of blood oxygenation and investigate the application of the Monte-Carlo method in a model-based inversion scheme. A forward model of the light transport based on the MCX simulator and acoustic propagation modeled by the k-Wave toolbox was used to generate a PA image data set acquired in a tissue phantom over a planar detection geometry. The combination of the optical and acoustic models is shown to account for limited-view artifacts. In addition, the errors in the fluence due to, for example, partial volume artifacts and absorbers immediately adjacent to the region of interest are investigated. To accomplish large-scale inversions in 3D, the number of degrees of freedom is reduced by applying image segmentation to the initial pressure distribution to extract a limited number of regions with homogeneous optical parameters. The absorber concentration in the tissue phantom was estimated using a coordinate descent parameter search based on the comparison between measured and modeled PA spectra. The estimated relative concentrations using this approach lie within 5 % compared to the known concentrations. Finally, we discuss the feasibility of this approach to recover the blood oxygenation from experimental data. Y1 - 2017 U6 - https://doi.org/10.1117/12.2251945 VL - 10064 SP - 100645J EP - 100645J-13 ER - TY - CHAP A1 - Buchmann, Jens A1 - Kaplan, Bernhard A1 - Prohaska, Steffen A1 - Laufer, Jan T1 - Experimental validation of a Monte-Carlo-based inversion scheme for 3D quantitative photoacoustic tomography T2 - Proc. of SPIE, Photons Plus Ultrasound: Imaging and Sensing N2 - Quantitative photoacoustic tomography (qPAT) aims to extract physiological parameters, such as blood oxygen saturation (sO2), from measured multi-wavelength image data sets. The challenge of this approach lies in the inherently nonlinear fluence distribution in the tissue, which has to be accounted for by using an appropriate model, and the large scale of the inverse problem. In addition, the accuracy of experimental and scanner-specific parameters, such as the wavelength dependence of the incident fluence, the acoustic detector response, the beam profile and divergence, needs to be considered. This study aims at quantitative imaging of blood sO2, as it has been shown to be a more robust parameter compared to absolute concentrations. We propose a Monte-Carlo–based inversion scheme in conjunction with a reduction in the number of variables achieved using image segmentation. The inversion scheme is experimentally validated in tissue-mimicking phantoms consisting of polymer tubes suspended in a scattering liquid. The tubes were filled with chromophore solutions at different concentration ratios. 3-D multi-spectral image data sets were acquired using a Fabry-Perot based PA scanner. A quantitative comparison of the measured data with the output of the forward model is presented. Parameter estimates of chromophore concentration ratios were found to be within 5 % of the true values. Y1 - 2017 U6 - https://doi.org/10.1117/12.2252359 VL - 10064 SP - 1006416 EP - 1006416-8 ER - TY - GEN A1 - Zhukova, Yulia A1 - Hiepen, Christian A1 - Knaus, Petra A1 - Osterland, Marc A1 - Prohaska, Steffen A1 - Dunlop, John W. C. A1 - Fratzl, Peter A1 - Skorb, Ekaterina V. T1 - The role of titanium surface nanotopography on preosteoblast morphology, adhesion and migration N2 - Surface structuring of titanium-based implants with appropriate nanotopographies can significantly modulate their impact on the biological behavior of cells populating these implants. Implant assisted bone tissue repair and regeneration require functional adhesion and expansion of bone progenitors. The surface nanotopography of implant materials used to support bone healing and its effect on cell behavior, in particular cell adhesion, spreading, expansion, and motility, is still not clearly understood. The aim of this study is to investigate preosteoblast proliferation, adhesion, morphology, and migration on different titanium materials with similar surface chemistry, but distinct nanotopographical features. Sonochemical treatment and anodic oxidation were employed to fabricate disordered – mesoporous titania (TMS), and ordered – titania nanotubular (TNT) topographies respectively. The morphological evaluation revealed a surface dependent shape, thickness, and spreading of cells owing to different adherence behavior. Cells were polygonal-shaped and well-spread on glass and TMS, but displayed an elongated fibroblast-like morphology on TNT surfaces. The cells on glass however, were much flatter than on nanostructured surfaces. Both nanostructured surfaces impaired cell adhesion, but TMS was more favorable for cell growth due to its support of cell attachment and spreading in contrast to TNT. Quantitative wound healing assay in combination with live-cell imaging revealed that cells seeded on TMS surfaces migrated in close proximity to neighboring cells and less directed when compared to the migratory behavior on other surfaces. The results indicate distinctly different cell adhesion and migration on ordered and disordered titania nanotopographies, providing important information that could be used in optimizing titanium-based scaffold design to foster bone tissue growth and repair. T3 - ZIB-Report - 17-06 Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-63053 SN - 1438-0064 ER -