2019

Matthias Strauch, Jan Philip Kolb, Daniel Weng, Melanie Wacker, Wolfgang Draxinger, Sebastian Karpf, and Robert Huber,
Sectioning-Free Virtual H&E Imaging of Tissue Samples with Two-Photon Microscopy, in 31st Congress of the ESP , 2019.
DOI:10.1007/s00428-019-02631-8
Bibtex: BibTeX
@InProceedings{Strauch2019,
  author    = {Strauch, Matthias and Kolb, Jan Philip and Weng, Daniel and Wacker, Melanie and Draxinger, Wolfgang and Karpf, Sebastian and Huber, Robert},
  booktitle = {31st Congress of the ESP},
  title     = {Sectioning-Free Virtual H&E Imaging of Tissue Samples with Two-Photon Microscopy},
  year      = {2019},
  keywords  = {AG-Huber_NL},
}
Hinnerk Schulz-Hildebrandt, Naja Meyer-Schell, Malte Casper, Michael Evers, and Dieter Manstein,
Monitoring temperature induced phase changes in subcutaneous fatty tissue using an astigmatism corrected dynamic needle probe, in Proc. SPIE 11073, Clinical and Preclinical Optical Diagnostics II , 2019. pp. 1--3.
DOI:10.1117/12.2527087
ISBN:9781510628397
Bibtex: BibTeX
@inproceedings{Schulz-Hildebrandt2019,
author = {Schulz-Hildebrandt, Hinnerk and Meyer-Schell, Naja and Casper, Malte and Evers, Michael and Birngruber, Reginald and Manstein, Dieter and H{\"{u}}ttmann, Gereon},
booktitle = {Proc. SPIE 11073, Clinical and Preclinical Optical Diagnostics II},
doi = {10.1117/12.2527087},
isbn = {9781510628397},
number = {110730L},
pages = {1--3},
title = {{Monitoring temperature induced phase changes in subcutaneous fatty tissue using an astigmatism corrected dynamic needle probe}},
keywords = {OCT, Endoskope},
year = { 2019}
}

2018

Hinnerk Schulz-Hildebrandt, Michael Münter, Martin Ahrens, Hendrik Spahr, Dierck Hillmann, Peter König, and Gereon Hüttmann,
Coherence and diffraction limited resolution in microscopic OCT by a unified approach for the correction of dispersion and aberrations, in 2nd Canterbury Conference on OCT with Emphasis on Broadband Optical Sources , 2018. pp. 105910O.
DOI:10.1117/12.2303755
ISBN:9781510616745
Bibtex: BibTeX
@inproceedings{Schulz-Hildebrandt2018a,
title = {Coherence and diffraction limited resolution in microscopic OCT by a unified approach for the correction of dispersion and aberrations},
author = {Schulz-Hildebrandt,H; M\"{u}nter, M; Ahrens,M; Spahr, H; Hillmann, D; K\"{o}nig, P and  H\"{u}ttmann, G},
doi = {10.1117/12.2303755},
isbn = {9781510616745},
year = {2018},
date = {2018-03-05},
booktitle = {2nd Canterbury Conference on OCT with Emphasis on Broadband Optical Sources},
volume = {10591},
pages = {105910O},
abstract = {Optical coherence tomography (OCT) images scattering tissues with 5 to 15 μm resolution. This is usually not sufficient for a distinction of cellular and subcellular structures. Increasing axial and lateral resolution and compensation of artifacts caused by dispersion and aberrations is required to achieve cellular and subcellular resolution. This includes defocus which limit the usable depth of field at high lateral resolution. OCT gives access the phase of the scattered light and hence correction of dispersion and aberrations is possible by numerical algorithms. Here we present a unified dispersion/aberration correction which is based on a polynomial parameterization of the phase error and an optimization of the image quality using Shannon’s entropy. For validation, a supercontinuum light sources and a costume-made spectrometer with 400 nm bandwidth were combined with a high NA microscope objective in a setup for tissue and small animal imaging. Using this setup and computation corrections, volumetric imaging at 1.5 μm resolution is possible. Cellular and near cellular resolution is demonstrated in porcine cornea and the drosophila larva, when computational correction of dispersion and aberrations is used. Due to the excellent correction of the used microscope objective, defocus was the main contribution to the aberrations. In addition, higher aberrations caused by the sample itself were successfully corrected. Dispersion and aberrations are closely related artifacts in microscopic OCT imaging. Hence they can be corrected in the same way by optimization of the image quality. This way microscopic resolution is easily achieved in OCT imaging of static biological tissues.},
keywords = {OCM},
pubstate = {published},
tppubtype = {inproceedings}
}
D Smits, and E.B Vander Poorten,
Development and Experimental Validation of a Combined FBG Force and OCT Distance Sensing Needle for Robot-Assisted Retinal Vein Cannulation, 2018. pp. 129-134.
DOI:10.1109/ICRA.2018.8460983
Bibtex: BibTeX
@inproceedings{Smits2018,
title = {Development and Experimental Validation of a Combined FBG Force and OCT Distance Sensing Needle for Robot-Assisted Retinal Vein Cannulation},
author = {Smits, J; Ourak, M; Gijbels, A;  Esteveny, L; Borghesan, G; Schoevaerdts, L; Willekens; Stalmans, P; Lankenau, E; Schulz-Hildebrandt, H; H\"{u}ttmann, G; Reynaerts, D and  Vander Poorten, E.B},

doi = {10.1109/ICRA.2018.8460983},
year = {2018},
date = {2018-09-20},
journal = {2018 IEEE Intern Conf Robot a Automation (ICRA)},
pages = {129-134},
abstract = {Retinal Vein Occlusion is a common retinal vascular disorder which can cause severe loss of vision. Retinal vein cannulation followed by injection of an anti-coagulant into the affected vein is a promising treatment. However, given the scale and fragility of the surgical workfield, this procedure is considered too high-risk to perform manually. A first successful robot-assisted procedure has been demonstrated. Even though successful, the procedure remains extremely challenging. This paper aims at providing a solution for the limited perception of instrument-tissue interaction forces as well as depth estimation during retinal vein cannulation. The development of a novel combined force and distance sensing cannulation needle relying on Fiber Bragg grating (FBG) and Optical Coherence Tomography (OCT) A-scan technology is reported. The design, the manufacturing process, the calibration method, and the experimental characterization of the produced sensor are discussed. 
The functionality of the combined sensing modalities and the real-time distance estimation algorithm are validated respectively on in-vitro and ex-vivo models.},
keywords = {Endoskope},
pubstate = {published},
tppubtype = {inproceedings}
}
Gijs Cecchetti,
Heartbeat optical coherence tomography enables accurate in vivo stents imaging: a quantitative image processing study (Conference Presentation), in Diagnostic and Therapeutic Applications of Light in Cardiology 2019 , International Society for Optics and Photonics, 2018. pp. 1085506.
Bibtex: BibTeX
@inproceedings{Cecchetti2019,
   author = {Cecchetti, Leonardo;Wang, Tianshi;Pfeiffer, Tom;Wieser, Wolfgang;van der Steen, Antonius FW;Huber, Robert;van Soest, Gijs and Huber, Robert Alexander},
   title = {Heartbeat optical coherence tomography enables accurate in vivo stents imaging: a quantitative image processing study (Conference Presentation)},
   booktitle = {Diagnostic and Therapeutic Applications of Light in Cardiology 2019},
   publisher = {International Society for Optics and Photonics},
   volume = {10855},
   pages = {1085506},
   type = {Conference Proceedings}
}
Ralph Hakert,
Label-free imaging of tumorous tissue in the Raman fingerprint region with time-encoded (TICO) stimulated Raman scattering (Conference Presentation), in Multiphoton Microscopy in the Biomedical Sciences XIX , International Society for Optics and Photonics, 2018. pp. 108821R.
Bibtex: BibTeX
@inproceedings{Hakert2019,
   author = {Hakert, Hubertus;Eibl, Matthias;Karpf, Sebastian;Wollenberg, Barbara;Pries, Ralph and Huber, Robert},
   title = {Label-free imaging of tumorous tissue in the Raman fingerprint region with time-encoded (TICO) stimulated Raman scattering (Conference Presentation)},
   booktitle = {Multiphoton Microscopy in the Biomedical Sciences XIX},
   publisher = {International Society for Optics and Photonics},
   volume = {10882},
   pages = {108821R},
   type = {Conference Proceedings}
}
Robert Wang, and Gijs van Soest,
Megahertz intravascular Doppler optical coherence tomography enables simultaneous morphological and flow pattern imaging, in Diagnostic and Therapeutic Applications of Light in Cardiology 2019 , International Society for Optics and Photonics, 2018. pp. 1085503.
Bibtex: BibTeX
@inproceedings{Wang2019-3,
   author = {Wang, Tianshi;Pfeiffer, Tom;Daemen, Joost;Mastik, Frits;Wieser, Wolfgang;van der Steen, AFW;Huber, Robert and van Soest, Gijs},
   title = {Megahertz intravascular Doppler optical coherence tomography enables simultaneous morphological and flow pattern imaging},
   booktitle = {Diagnostic and Therapeutic Applications of Light in Cardiology 2019},
   publisher = {International Society for Optics and Photonics},
   volume = {10855},
   pages = {1085503},
   type = {Conference Proceedings}
}
Robert Wang, and Gijs van Soest,
Thermo-elastic optical coherence tomography, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIII , International Society for Optics and Photonics, 2018. pp. 108672C.
Bibtex: BibTeX
@inproceedings{Wang2019-1,
   author = {Wang, Tianshi;Pfeiffer, Tom;Wieser, Wolfgang;van Beusekom, Heleen;Draxinger, Wolfgang;van der Steen, Antonius FW;Huber, Robert and van Soest, Gijs},
   title = {Thermo-elastic optical coherence tomography},
   booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIII},
   publisher = {International Society for Optics and Photonics},
   volume = {10867},
   pages = {108672C},
   type = {Conference Proceedings}
}
R Uzunbajakava, and A Vogel,
Highlighting the nuances behind interaction of picosecond pulses with human skin: Relating distinct laser-tissue interactions to their potential in cutaneous interventions, in Progress in Biomedical Optics and Imaging - Proceedings of SPIE , 2018.
DOI:10.1117/12.2307804
Bibtex: BibTeX
@inproceedings{Vogel2018,
   author = {Uzunbajakava, N E; Varghese, B; Botchkareva, N V; Verhagen, R and Vogel, A},
   title = {Highlighting the nuances behind interaction of picosecond pulses with human skin: Relating distinct laser-tissue interactions to their potential in cutaneous interventions},
   booktitle = {Progress in Biomedical Optics and Imaging - Proceedings of SPIE},
   volume = {10492} ,
   DOI = {10.1117/12.2307804},
   year = {2018},
date = {2018-20-02},
   type = {Conference Proceedings},
year = { 2018}
}

2017

Tianshi Wang, Tom Pfeiffer, Min Wu, Wolfgang Wieser, Gaetano Amenta, Wolfgang Draxinger, Antonius F. W. van der Steen, Robert Huber, and Gijs van Soest,
Thermo-elastic optical coherence tomography, Optica Publishing Group, Sep.2017. pp. 3466-3469.
DOI:10.1364/OL.42.003466
Bibtex: BibTeX
@article{Wang:17,
author = {Tianshi Wang and Tom Pfeiffer and Min Wu and Wolfgang Wieser and Gaetano Amenta and Wolfgang Draxinger and Antonius F. W. van der Steen and Robert Huber and Gijs van Soest},
journal = {Opt. Lett.},
keywords = {Imaging systems; Medical and biological imaging; Optical coherence tomography; Lasers, pulsed ; Fourier domain mode locking; Functional imaging; Laser beams; Nanosecond pulses; Optical coherence tomography; Phantom studies},
number = {17},
pages = {3466--3469},
publisher = {Optica Publishing Group},
title = {Thermo-elastic optical coherence tomography},
volume = {42},
month = {Sep},
year = {2017},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-42-17-3466},
doi = {10.1364/OL.42.003466},
abstract = {The absorption of nanosecond laser pulses induces rapid thermo-elastic deformation in tissue. A sub-micrometer scale displacement occurs within a few microseconds after the pulse arrival. In this Letter, we investigate the laser-induced thermo-elastic deformation using a 1.5 MHz phase-sensitive optical coherence tomography (OCT) system. A displacement image can be reconstructed, which enables a new modality of phase-sensitive OCT, called thermo-elastic OCT. An analysis of the results shows that the optical absorption is a dominating factor for the displacement. Thermo-elastic OCT is capable of visualizing inclusions that do not appear on the structural OCT image, providing additional tissue type information.},
}
Jan Philip Kolb, Julian Klee, Tom Pfeiffer, and Robert Huber,
1060nm FDML laser with centimeter coherence length and 1.67 MHz sweep rate for full eye length and retinal ultra-widefield OCT, in Optical Coherence Imaging Techniques and Imaging in Scattering Media II , Maciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh, Eds. SPIE, Aug.2017. pp. 104160J.
DOI:10.1117/12.2286854
Bibtex: BibTeX
@inproceedings{10.1117/12.2286854,
author = {Jan Philip Kolb and Julian Klee and Tom Pfeiffer and Robert Huber},
title = {{1060nm FDML laser with centimeter coherence length and 1.67 MHz sweep rate for full eye length and retinal ultra-widefield OCT}},
volume = {10416},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media II},
editor = {Maciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {104160J},
abstract = {We present a new design of a 1060nm Fourier Domain Mode Locked-Laser (FDML-Laser) that combines 1.67 MHz A-scan rate with a centimeter scale coherence length. The extended coherence length is achieved by synchronizing the cavity roundtrip time over the 75 nm sweep with a relative accuracy of 10<sup>-7</sup>. We will show that this requires careful combination of multiple fiber types in the cavity with a gradient heated chirped Fiber Bragg grating.},
keywords = {optical coherence tomograhy, OCT, tunable laser, Fourier domain mode locking, FDML, MHz OCT},
year = {2017},
doi = {10.1117/12.2286854},
URL = {https://doi.org/10.1117/12.2286854}
}
Tom Pfeiffer, Wolfgang Draxinger, Christin Grill, and Robert Huber,
Long-range live 3D-OCT at different spectral zoom levels, in Optical Coherence Imaging Techniques and Imaging in Scattering Media II , Maciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh, Eds. SPIE, Aug.2017. pp. 104160L.
DOI:10.1117/12.2287484
Bibtex: BibTeX
@inproceedings{10.1117/12.2287484,
author = {Tom Pfeiffer and Wolfgang Draxinger and Christin Grill and Robert Huber},
title = {{Long-range live 3D-OCT at different spectral zoom levels}},
volume = {10416},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media II},
editor = {Maciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {104160L},
abstract = {We demonstrate that the 3.2 MHz a-scan rate and the improved coherence of our new low noise FDML laser enables live 3D-OCT with different spectral zooms and up to 10 cm of imaging range.},
keywords = {Optical coherence tomography, Fourier Domain Mode Locking, FDML, OCT},
year = {2017},
doi = {10.1117/12.2287484},
URL = {https://doi.org/10.1117/12.2287484}
}
Matthias Eibl, Sebastian Karpf, Hubertus Hakert, Daniel Weng, Tom Pfeiffer, Jan Philip Kolb, and Robert Huber,
Single pulse two-photon fluorescence lifetime imaging (SP-FLIM) with MHz pixel rate and an all fiber based setup, in Advances in Microscopic Imaging , Emmanuel Beaurepaire and Francesco Saverio Pavone and Peter T. C. So, Eds. SPIE, Jul.2017. pp. 1041403.
DOI:10.1117/12.2286035
Bibtex: BibTeX
@inproceedings{10.1117/12.2286035,
author = {Matthias Eibl and Sebastian Karpf and Hubertus Hakert and Daniel Weng and Tom Pfeiffer and Jan Philip Kolb and Robert Huber},
title = {{Single pulse two-photon fluorescence lifetime imaging (SP-FLIM) with MHz pixel rate and an all fiber based setup }},
volume = {10414},
booktitle = {Advances in Microscopic Imaging},
editor = {Emmanuel Beaurepaire and Francesco Saverio Pavone and Peter T. C. So},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1041403},
abstract = {Newly developed microscopy methods have the goal to give researches in bio-molecular science a better understanding of processes ongoing on a cellular level. Especially two-photon excited fluorescence (TPEF) microscopy is a readily applied and widespread modality. Compared to one photon fluorescence imaging, it is possible to image not only the surface but also deeper lying structures. Together with fluorescence lifetime imaging (FLIM), which provides information on the chemical composition of a specimen, deeper insights on a molecular level can be gained. However, the need for elaborate light sources for TPEF and speed limitations for FLIM hinder an even wider application. In this contribution, we present a way to overcome this limitations by combining a robust and inexpensive fiber laser for nonlinear excitation with a fast analog digitization method for rapid FLIM imaging. The applied sub nanosecond pulsed laser source is perfectly suited for fiber delivery as typically limiting non-linear effects like self-phase or cross-phase modulation (SPM, XPM) are negligible. Furthermore, compared to the typically applied femtosecond pulses, our longer pulses produce much more fluorescence photons per single shot. In this paper, we show that this higher number of fluorescence photons per pulse combined with a high analog bandwidth detection makes it possible to not only use a single pulse per pixel for TPEF imaging but also to resolve the exponential time decay for FLIM. To evaluate our system, we acquired FLIM images of a dye solution with single exponential behavior to assess the accuracy of our lifetime determination and also FLIM images of a plant stem at a pixel rate of 1 MHz to show the speed performance of our single pulse two-photon FLIM (SP-FLIM) system.},
keywords = {Nonlinear microscopy, Fluorescence microscopy, Fiber optics imaging, Lifetime-based sensing, Lasers, fiber, Nonlinear optics, fibers},
year = {2017},
doi = {10.1117/12.2286035},
URL = {https://doi.org/10.1117/12.2286035}
}
Hubertus Hakert, Matthias Eibl, Sebastian Karpf, and Robert Huber,
Sparse-sampling with time-encoded (TICO) stimulated Raman scattering for fast image acquisition, in Advances in Microscopic Imaging , Emmanuel Beaurepaire and Francesco Saverio Pavone and Peter T. C. So, Eds. SPIE, Jul.2017. pp. 1041408.
DOI:10.1117/12.2287947
Bibtex: BibTeX
@inproceedings{10.1117/12.2287947,
author = {Hubertus Hakert and Matthias Eibl and Sebastian Karpf and Robert Huber},
title = {{Sparse-sampling with time-encoded (TICO) stimulated Raman scattering for fast image acquisition}},
volume = {10414},
booktitle = {Advances in Microscopic Imaging},
editor = {Emmanuel Beaurepaire and Francesco Saverio Pavone and Peter T. C. So},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1041408},
abstract = {Modern biomedical imaging modalities aim to provide researchers a multimodal contrast for a deeper insight into a
specimen under investigation. A very promising technique is stimulated Raman scattering (SRS) microscopy, which can
unveil the chemical composition of a sample with a very high specificity. Although the signal intensities are enhanced
manifold to achieve a faster acquisition of images if compared to standard Raman microscopy, there is a trade-off between
specificity and acquisition speed. Commonly used SRS concepts either probe only very few Raman transitions as the
tuning of the applied laser sources is complicated or record whole spectra with a spectrometer based setup. While the first
approach is fast, it reduces the specificity and the spectrometer approach records whole spectra -with energy differences
where no Raman information is present-, which limits the acquisition speed. Therefore, we present a new approach based
on the TICO-Raman concept, which we call sparse-sampling. The TICO-sparse-sampling setup is fully electronically
controllable and allows probing of only the characteristic peaks of a Raman spectrum instead of always acquiring a whole
spectrum. By reducing the spectral points to the relevant peaks, the acquisition time can be greatly reduced compared to a
uniformly, equidistantly sampled Raman spectrum while the specificity and the signal to noise ratio (SNR) are maintained.
Furthermore, all laser sources are completely fiber based. The synchronized detection enables a full resolution of the
Raman signal, whereas the analogue and digital balancing allows shot noise limited detection. First imaging results with
polystyrene (PS) and polymethylmethacrylate (PMMA) beads confirm the advantages of TICO sparse-sampling. We
achieved a pixel dwell time as low as 35 μs for an image differentiating both species. The mechanical properties of the
applied voice coil stage for scanning the sample currently limits even faster acquisition.},
keywords = {nonlinear microscopy, fiber optics imaging, stimulated raman scattering microscopy, time encoded, sparse sampling, Raman spectroscopy , Fourier Domain Mode Locked Laser, FDML, Lasers, fiber},
year = {2017},
doi = {10.1117/12.2287947},
URL = {https://doi.org/10.1117/12.2287947}
}
Matthias Eibl, Sebastian Karpf, Hubertus Hakert, Daniel Weng, Torben Blömker, and Robert Huber,
Pulse-to-pulse wavelength switching of diode based fiber laser for multi-color multi-photon imaging, in Fiber Lasers XIV: Technology and Systems , Craig A. Robin and Ingmar Hartl, Eds. SPIE, Mä.2017. pp. 100831C.
DOI:10.1117/12.2251965
Bibtex: BibTeX
@inproceedings{10.1117/12.2251965,
author = {Matthias Eibl and Sebastian Karpf and Hubertus Hakert and Daniel Weng and Torben Bl{\"o}mker and Robert Huber},
title = {{Pulse-to-pulse wavelength switching of diode based fiber laser for multi-color multi-photon imaging}},
volume = {10083},
booktitle = {Fiber Lasers XIV: Technology and Systems},
editor = {Craig A. Robin and Ingmar Hartl},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {100831C},
abstract = {We present an entirely fiber based laser source for non-linear imaging with a novel approach for multi-color excitation. The high power output of an actively modulated and amplified picosecond fiber laser at 1064 nm is shifted to longer wavelengths by a combination of four-wave mixing and stimulated Raman scattering. By combining different fiber types and lengths, we control the non-linear wavelength conversion in the delivery fiber itself and can switch between 1064 nm, 1122 nm, and 1186 nm on-the-fly by tuning the pump power of the fiber amplifier and modulate the seed diodes. This is a promising way to enhance the applicability of short pulsed laser diodes for bio-molecular non-linear imaging by reducing the spectral limitations of such sources. In comparison to our previous work [1, 2], we show for the first time two-photon imaging with the shifted wavelengths and we demonstrate pulse-to-pulse switching between the different wavelengths without changing the configuration.},
keywords = {stimulated raman scattering, two-photon imaging, fiber amplifier, four-wave-mixing, wavelength conversion, non-linear imaging},
year = {2017},
doi = {10.1117/12.2251965},
URL = {https://doi.org/10.1117/12.2251965}
}
Max-Heinrich Laves, Andreas Schoob, Lüder A. Kahrs, Tom Pfeiffer, Robert Huber, and Tobias Ortmaier,
Feature tracking for automated volume of interest stabilization on 4D-OCT images, in Medical Imaging 2017: Image-Guided Procedures, Robotic Interventions, and Modeling , Robert J. Webster III and Baowei Fei, Eds. SPIE, Mä.2017. pp. 101350W.
DOI:10.1117/12.2255090
Bibtex: BibTeX
@inproceedings{10.1117/12.2255090,
author = {Max-Heinrich Laves and Andreas Schoob and L{\"u}der A. Kahrs and Tom Pfeiffer and Robert Huber and Tobias Ortmaier},
title = {{Feature tracking for automated volume of interest stabilization on 4D-OCT images}},
volume = {10135},
booktitle = {Medical Imaging 2017: Image-Guided Procedures, Robotic Interventions, and Modeling},
editor = {Robert J. Webster III and Baowei Fei},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {101350W},
abstract = {A common representation of volumetric medical image data is the triplanar view (TV), in which the surgeon manually selects slices showing the anatomical structure of interest. In addition to common medical imaging such as MRI or computed tomography, recent advances in the field of optical coherence tomography (OCT) have enabled live processing and volumetric rendering of four-dimensional images of the human body. Due to the region of interest undergoing motion, it is challenging for the surgeon to simultaneously keep track of an object by continuously adjusting the TV to desired slices. To select these slices in subsequent frames automatically, it is necessary to track movements of the volume of interest (VOI). This has not been addressed with respect to 4DOCT images yet. Therefore, this paper evaluates motion tracking by applying state-of-the-art tracking schemes on maximum intensity projections (MIP) of 4D-OCT images. Estimated VOI location is used to conveniently show corresponding slices and to improve the MIPs by calculating thin-slab MIPs. Tracking performances are evaluated on an in-vivo sequence of human skin, captured at 26 volumes per second. Among investigated tracking schemes, our recently presented tracking scheme for soft tissue motion provides highest accuracy with an error of under 2.2 voxels for the first 80 volumes. Object tracking on 4D-OCT images enables its use for sub-epithelial tracking of microvessels for image-guidance.},
keywords = {4D imaging, maximum intensity projection, optical coherence tomography, feature tracking},
year = {2017},
doi = {10.1117/12.2255090},
URL = {https://doi.org/10.1117/12.2255090}
}
Matthias Eibl, Sebastian Karpf, Hubertus Hakert, Daniel Weng, and Robert Huber,
Two-photon-excited fluorescence (TPEF) and fluorescence lifetime imaging (FLIM) with sub-nanosecond pulses and a high analog bandwidth signal detection, in Multiphoton Microscopy in the Biomedical Sciences XVII , Ammasi Periasamy and Peter T. C. So and Karsten König and Xiaoliang S. Xie, Eds. SPIE, Feb.2017. pp. 100691F.
DOI:10.1117/12.2250831
Bibtex: BibTeX
@inproceedings{10.1117/12.2250831,
author = {Matthias Eibl and Sebastian Karpf and Hubertus Hakert and Daniel Weng and Robert Huber},
title = {{Two-photon-excited fluorescence (TPEF) and fluorescence lifetime imaging (FLIM) with sub-nanosecond pulses and a high analog bandwidth signal detection}},
volume = {10069},
booktitle = {Multiphoton Microscopy in the Biomedical Sciences XVII},
editor = {Ammasi Periasamy and Peter T. C. So and Karsten K{\"o}nig and Xiaoliang S. Xie},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {100691F},
abstract = {Two-photon excited fluorescence (TPEF) microscopy and fluorescence lifetime imaging (FLIM) are powerful imaging techniques in bio-molecular science. The need for elaborate light sources for TPEF and speed limitations for FLIM, however, hinder an even wider application. We present a way to overcome this limitations by combining a robust and inexpensive fiber laser for nonlinear excitation with a fast analog digitization method for rapid FLIM imaging. The applied sub nanosecond pulsed laser source is synchronized to a high analog bandwidth signal detection for single shot TPEF- and single shot FLIM imaging. The actively modulated pulses at 1064nm from the fiber laser are adjustable from 50ps to 5ns with kW of peak power. At a typically applied pulse lengths and repetition rates, the duty cycle is comparable to typically used femtosecond pulses and thus the peak power is also comparable at same cw-power. Hence, both types of excitation should yield the same number of fluorescence photons per time on average when used for TPEF imaging. However, in the 100ps configuration, a thousand times more fluorescence photons are generated per pulse. In this paper, we now show that the higher number of fluorescence photons per pulse combined with a high analog bandwidth detection makes it possible to not only use a single pulse per pixel for TPEF imaging but also to resolve the exponential time decay for FLIM. To evaluate the performance of our system, we acquired FLIM images of a Convallaria sample with pixel rates of 1 MHz where the lifetime information is directly measured with a fast real time digitizer. With the presented results, we show that longer pulses in the many-10ps to nanosecond regime can be readily applied for TPEF imaging and enable new imaging modalities like single pulse FLIM.},
keywords = {FLIM, TPEF, fiber laser, endoscope, MOPA, Nonlinear microscopy, Fluorescence microscopy, Lifetime-based sensing},
year = {2017},
doi = {10.1117/12.2250831},
URL = {https://doi.org/10.1117/12.2250831}
}
Tianshi Wang, Tom Pfeiffer, Min Wu, Wolfgang Wieser, Wolfgang Draxinger, Antonius F. W. van der Steen, Robert Huber, and Gijs van Soest,
Short pulse laser induced thermo-elastic deformation imaging, in Optical Interactions with Tissue and Cells XXVIII , E. Duco Jansen and Hope Thomas Beier, Eds. SPIE, Feb.2017. pp. 100620C.
DOI:10.1117/12.2251502
Bibtex: BibTeX
@inproceedings{10.1117/12.2251502,
author = {Tianshi Wang and Tom Pfeiffer and Min Wu and Wolfgang Wieser and Wolfgang Draxinger and Antonius F. W. van der Steen and Robert Huber and Gijs van Soest},
title = {{Short pulse laser induced thermo-elastic deformation imaging}},
volume = {10062},
booktitle = {Optical Interactions with Tissue and Cells XXVIII},
editor = {E. Duco Jansen and Hope Thomas Beier},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {100620C},
abstract = {Absorption of nanosecond laser pulses induces rapid thermo-elastic deformation in tissue, i.e. a sub-micrometer scale displacement happens within a couple of microseconds. In this study, we initially investigate the depth-resolved deformation using a 1.5 MHz phase-sensitive optical coherence tomography (OCT) system. Functional images can be reconstructed based on the detected deformation, which enables a new imaging modality called thermo-elastic deformation imaging (TDI). Our results show that the associated displacement is related to the optical absorption of the short laser pulses. The TDI images can provide tissue type information in addition to the conventional OCT images.},
keywords = {thermal-elastic deformation, optical coherence tomography},
year = {2017},
doi = {10.1117/12.2251502},
URL = {https://doi.org/10.1117/12.2251502}
}
Tom Pfeiffer, Wolfgang Draxinger, Wolfgang Wieser, Thomas Klein, Markus Petermann, and Robert Huber,
Analysis of FDML lasers with meter range coherence, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXI , James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin, Eds. SPIE, 2017. pp. 100531T.
DOI:10.1117/12.2254792
Bibtex: BibTeX
@inproceedings{10.1117/12.2254792,
author = {Tom Pfeiffer and Wolfgang Draxinger and Wolfgang Wieser and Thomas Klein and Markus Petermann and Robert Huber},
title = {{Analysis of FDML lasers with meter range coherence}},
volume = {10053},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXI},
editor = {James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {100531T},
abstract = {FDML lasers provide sweep rates in the MHz range at wide optical bandwidths, making them ideal sources for high
speed OCT. Recently, at lower speed, ultralong-range swept-source OCT has been demonstrated using a tunable
vertical cavity surface emitting laser (VCSEL) and also using a Vernier-tunable laser. These sources provide relatively
high sweep rates and meter range coherence lengths. In order to achieve similar coherence, we developed an extremely
well dispersion compensated Fourier Domain Mode Locked (FDML) laser, running at 3.2 MHz sweep rate and 120 nm
spectral bandwidth. We demonstrate that this laser offers meter range coherence and enables volumetric long range OCT
of moving objects.},
keywords = {Optical coherence tomography, OCT, tunable laser, Fourier domain mode locking, FDML, MHz OCT},
year = {2017},
doi = {10.1117/12.2254792},
URL = {https://doi.org/10.1117/12.2254792}
}
R Bliedtner, and Amelink A,
Real Time Speckle Monitoring to Control Retinal Photocoagulation, in Proc. SPIE , 2017. pp. 1041308-1-7.
Datei: 12.2287815
Bibtex: BibTeX
@inproceedings{Bliedtner2017,
   author = {Bliedtner, K; Seifert, E; Brinkmann, R and  Amelink A},
   title = {Real Time Speckle Monitoring to Control Retinal Photocoagulation},
   booktitle = {Proc. SPIE},
   
   pages = {1041308-1-7},
  
url = { https://doi.org/10.1117/12.2287815},
Year = { 2017}
}

2016

H P Urbach,
Surface harmonics on liquid lenses, in 2016 IEEE Photonics Conference (IPC) , Okt.2016. pp. 248-249.
DOI:10.1109/IPCon.2016.7831063
Bibtex: BibTeX
@INPROCEEDINGS{Strauch2017,
author={Strauch, M and Urbach, H P},
booktitle={2016 IEEE Photonics Conference (IPC)},
title={Surface harmonics on liquid lenses},
year={2016},

pages={248-249},
keywords={lenses;optical harmonic generation;optical tuning;oscillations;surface harmonics;liquid lenses;tunability;nonspherical surfaces;surface oscillations;Lenses;Liquids;Surface waves;Optical surface waves;Harmonic analysis;Shape;Optical switches},
doi={10.1109/IPCon.2016.7831063},
ISSN={},
month={Oct},}
Sijia Wang, Gereon Hüttmann, Tayyaba Hasan, and Ramtin Rahmanzadeh,
Molecular targeted PDT with selective delivery of ICG Photo-Immunoconjugates(Conference Presentation), in Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XXV , David H. Kessel and Tayyaba Hasan, Eds. SPIE, Apr.2016. pp. 96940O.
DOI:10.1117/12.2217572
Datei: 12.2217572
Bibtex: BibTeX
@inproceedings{10.1117/12.2217572,
author = {Sijia Wang and Gereon H{\"u}ttmann and Tayyaba Hasan and Ramtin Rahmanzadeh},
title = {{Molecular targeted PDT with selective delivery of ICG Photo-Immunoconjugates
(Conference Presentation)}},
volume = {9694},
booktitle = {Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XXV},
editor = {David H. Kessel and Tayyaba Hasan},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {96940O},
keywords = {photodynamic therapy, liposome, endosomal entrapment, nanotechnology, cell proliferation, photochemical internalization},
year = {2016},
doi = {10.1117/12.2217572},
URL = {https://doi.org/10.1117/12.2217572}
}
Mario Pieper, Hinnerk Schulz-Hildebrandt, Gereon Hüttmann, and Peter König,
Imaging of mucus clearance in the airways of living spontaneously breathing mice by optical coherence microscopy (Conference Presentation), 2016. pp. 969116-969116-1.
Datei: 12.2209054
Bibtex: BibTeX
@inproceedings{Pieper2016,
   author = {Pieper, Mario and Schulz-Hildebrandt, Hinnerk and Hüttmann, Gereon and König, Peter},
   title = {Imaging of mucus clearance in the airways of living spontaneously breathing mice by optical coherence microscopy (Conference Presentation)},
   volume = {9691},
   pages = {969116-969116-1},
year = { 2016},
   note = {10.1117/12.2209054},
   abstract = {Mucus transport is essential to remove inhaled particles and pathogens from the lung. Impaired removal of mucus often results in worsening of lung diseases. To understand the mechanisms of mucus transport and to monitor the impact of therapeutic strategies, it is essential to visualize airways and mucus in living animals without disturbing transport processes by intubation or surgically opening the airways. We developed a custom-built optical coherence microscope (OCM) providing a lateral and axial resolution of approximately 1.5 µm with a field of view of 2 mm at up to 150 images/s. Images of the intact trachea and its mucus transport were recorded in anesthetized spontaneously breathing mice. NaCl solution (0.9% and 7%) or Lipopolysaccharide were applied intranasally. OCM resolved detailed structure of the trachea and enabled measuring the airway surface liquid (ASL) thickness through the tracheal wall. Without stimulation, the amount of ASL was only a few µm above the epithelium and remained constant. After intranasal application of 30 µl saline at different concentrations, an early fast cough-like fluid removal with velocities higher than 1 mm/s was observed that removed a high amount of liquid. The ASL thickness increased transiently and quickly returned to levels before stimulation. In contrast to saline, application of Lipopolysaccharide induced substantial mucus release and an additional slow mucus transport by ciliary beating (around 100 µm/s) towards the larynx was observed. In conclusion, OCM is appropriate unique tool to study mechanisms of mucus transport in the airways and effects of therapeutic interventions in living animals.},
   url = {http://dx.doi.org/10.1117/12.2209054},
   type = {Conference Proceedings}
}
Hendrik Spahr, Dierck Hillmann, Carola Hain, Clara Pfäffle, Helge Sudkamp, Gesa Franke, and Gereon Hüttmann,
Imaging vascular dynamics in human retina using full-field swept-source optical coherence tomography (Conference Presentation), 2016. pp. 96970E-96970E-1.
DOI:10.1117/12.2214303
Datei: 12.2214303
Bibtex: BibTeX
@inproceedings{Spahr2016,
   author = {Spahr, Hendrik and Hillmann, Dierck and Hain, Carola and Pfäffle, Clara and Sudkamp, Helge and Franke, Gesa and Hüttmann, Gereon},
   title = {Imaging vascular dynamics in human retina using full-field swept-source optical coherence tomography (Conference Presentation)},
   volume = {9697},
   pages = {96970E-96970E-1},
   note = {10.1117/12.2214303},
   abstract = {We demonstrate a new non-invasive method to assess the functional condition of the retinal vascular system. Phase-sensitive full-field swept-source optical coherence tomography (PhS-FF-SS-OCT) is used to investigate retinal vascular dynamics at unprecedented temporal resolution. Motion of retinal tissue, that is induced by expansion of the vessels therein, is measured with an accuracy of about 10 nm. The pulse shape of arterial and venous pulsation, their temporal delay as well as the frequency dependent pulse propagation through the capillary bed are determined. For the first time, imaging speed and motion sensitivity are sufficient for a direct measurement of pulse waves propagating with more than 600 mm/s in retinal vessels of a healthy young subject.},
   url = {http://dx.doi.org/10.1117/12.2214303},
   type = {Conference Proceedings},
year = { 2016}
}
Jan Philip Kolb, Thomas Klein, Matthias Eibl, Tom Pfeiffer, Wolfgang Wieser, and Robert Huber,
Megahertz FDML laser with up to 143nm sweep range for ultrahigh resolution OCT at 1050nm, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XX , Joseph A. Izatt and James G. Fujimoto and Valery V. Tuchin, Eds. SPIE, 2016. pp. 969703.
DOI:10.1117/12.2214758
Bibtex: BibTeX
@inproceedings{10.1117/12.2214758,
author = {Jan Philip Kolb and Thomas Klein and Matthias Eibl and Tom Pfeiffer and Wolfgang Wieser and Robert Huber},
title = {{Megahertz FDML laser with up to 143nm sweep range for ultrahigh resolution OCT at 1050nm}},
volume = {9697},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XX},
editor = {Joseph A. Izatt and James G. Fujimoto and Valery V. Tuchin},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {969703},
abstract = {We present a new design of a Fourier Domain Mode Locked laser (FDML laser), which provides a new record in sweep
range at ~1&mu;m center wavelength: At the fundamental sweep rate of 2x417 kHz we reach 143nm bandwidth and 120nm
with 4x buffering at 1.67MHz sweep rate. The latter configuration of our system is characterized: The FWHM of the
point spread function (PSF) of a mirror is 5.6&mu;m (in tissue). Human in vivo retinal imaging is performed with the MHz
laser showing more details in vascular structures. Here we could measure an axial resolution of 6.0μm by determining
the FWHM of specular reflex in the image. Additionally, challenges related to such a high sweep bandwidth such as
water absorption are investigated.},
keywords = {Optical coherence tomography, OCT, tunable laser, Fourier domain mode locking, FDML, MHz OCT},
year = {2016},
doi = {10.1117/12.2214758},
URL = {https://doi.org/10.1117/12.2214758}
}