Optical cohrence tomography (OCT)

Application and development of ultrafast MHz OCT systems

OCT is a noninvasive Imaging modality which is typically used for high resolution (~10µm), three dimensional imaging of scattering tissue. By using home built FDML laser technology we achieve imaging speeds of several million depth scans per second, which is one to two orders of magnitude higher than current commercially available systems (MHz-OCT).

These high imaging speeds already proved to be very useful in clinical applications, by reducing acquisition times and therefore reducing motion artifacts. But the high speed also gives access to the phase of the detected light and will thus allow the use of new numerical approaches for image quality enhancement and functional imaging with Swept-Source-OCT.

Our working group is conducting research in the field of OCT to develop new technologies and to identify possible fields of application.

The focus areas are:

  • MHz-OCT - Ultra-fast OCT imaging with several million depth scans per second
  • LARA-OCT - Large area robotically assisted OCT
  • VR-OCT - Real-time computation and rendering of entire OCT volumes in a virtual environment
  • Eye OCT - application of MHz-OCT to the eye for visualization of the retina or the anterior segment of the eye
  • Phase sensitive OCT - enhancement of the information content of an OCT image by adding phase contrast
  • Multispectral OCT - combination of RGB and OCT images for improved visualization of morphological structures

related Publications

2020

Paul Strenge, Birgit Lange, Christin Grill, Wolfgang Draxinger, Matteo M. Bonsanto, Christian Hagel, Robert Huber, and Ralf Brinkmann,
Segmented OCT data set for depth resolved brain tumor detection validated by histological analysis, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIV , SPIE, 022020. pp. 82 -- 89.
DOI:10.1117/12.2545659
Bibtex: BibTeX
@inproceedings{Strenge2020,
author = {P. Strenge and B. Lange and C. Grill and W. Draxinger and M. M. Bonsanto and C. Hagel and R. Huber and R. Brinkmann},
title = {{Segmented OCT data set for depth resolved brain tumor detection validated by histological analysis}},
volume = {11228},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIV},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {82 -- 89},
keywords = {AG-Huber_OCT, Optical coherence tomography, OCT, FDML Laser, MHz-OCT, brain tumor, brain imaging, neurosurgery},
year = {2020},

URL = {  https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11228/112282O/Segmented-OCT-data-set-for-depth-resolved-brain-tumor-detection/10.1117/12.2545659.short}
}
Leonardo Cecchetti, Tianshi Wang, Ayla Hoogendoorn, Karen T. Witberg, Jurgen M. R. Lighthart, Joost Daemen, Heleen van Beusekom, Tom Pfeiffer, Robert Huber, Jolanda Wentzel, Antonius F. W. van der Steen, and Gijs van Soest,
In-vitro and in-vivo imaging of coronary artery stents with Heartbeat OCT, The International Journal of Cardiovascular Imaging , vol. 36, no. 6, pp. 1021-1029, 02 2020. Springer Science and Business Media LLC.
DOI:10.1007/s10554-020-01796-7
Bibtex: BibTeX
@article{Cecchetti2020,
  doi = {10.1007/s10554-020-01796-7},
  url = {https://doi.org/10.1007/s10554-020-01796-7},
  year = {2020},
  month = feb,
  publisher = {Springer Science and Business Media {LLC}},
  volume = {36},
  number = {6},
  pages = {1021--1029},
  author = {Leonardo Cecchetti and Tianshi Wang and Ayla Hoogendoorn and Karen T. Witberg and Jurgen M. R. Ligthart and Joost Daemen and Heleen M. M. van Beusekom and Tom Pfeiffer and Robert A. Huber and Jolanda J. Wentzel and Antonius F. W. van der Steen and Gijs van Soest},
  title = {In-vitro and in-vivo imaging of coronary artery stents with Heartbeat {OCT}},
  journal = {The International Journal of Cardiovascular Imaging}
}

2019

Antonio López-Marín, Geert Springeling, Robert Beurskens, Heleen van Beusekom, Antonius F. W. van der Steen, Arjun D. Koch, Brett E. Bouma, Robert Huber, Gijs van Soest, and Tianshi Wang,
Motorized capsule for shadow-free OCT imaging and synchronous beam control, Opt Lett , vol. 44, no. 15, pp. 3641-3644, 08 2019. Optica Publishing Group.
DOI:10.1364/OL.44.003641
Bibtex: BibTeX
@article{Lopez-Marin:19,
author = {Antonio L\'{o}pez-Mar\'{i}n and Geert Springeling and Robert Beurskens and Heleen van Beusekom and Antonius F. W. van der Steen and Arjun D. Koch and Brett E. Bouma and Robert Huber and Gijs van Soest and Tianshi Wang},
journal = {Opt. Lett.},
keywords = {Image reconstruction; Light beams; Magnetic fields; Optical coherence tomography; Optical imaging; Reflector design},
number = {15},
pages = {3641--3644},
publisher = {Optica Publishing Group},
title = {Motorized capsule for shadow-free OCT imaging and synchronous beam control},
volume = {44},
month = {Aug},
year = {2019},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-44-15-3641},
doi = {10.1364/OL.44.003641},
abstract = {We demonstrate a tethered motorized capsule for unobstructed optical coherence tomography (OCT) imaging of the esophagus. By using a distal reflector design, we avoided the common shadow artifact induced by the motor wires. A synchronous driving technique features three types of beam-scanning modes of the capsule, i.e., circumferential beam scanning, localized beam scanning, and accurate beam positioning. We characterized these three modes and carried out ex vivo imaging experiments using the capsule. The results show that the capsule can potentially be a useful tool for diagnostic OCT imaging and OCT-guided biopsy and therapy of the esophagus.},
}
Julian Klee, Jan Philip Kolb, Christin Grill, Wolfgang Draxinger, Tom Pfeiffer, and Robert Huber,
Zero roll-off retinal MHz-OCT using an FDML-laser, in Optical Coherence Imaging Techniques and Imaging in Scattering Media III , SPIE, 072019. pp. 110780S.
DOI:10.1117/12.2527034
File: 12.2527034.short
Bibtex: BibTeX
@inproceedings{10.1117/12.2527034,
author = {Julian Klee and Jan Philip Kolb and Christin Grill and Wolfgang Draxinger and Tom Pfeiffer and Robert Huber},
title = {{Zero roll-off retinal MHz-OCT using an FDML-laser}},
volume = {11078},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media III},
editor = {Maciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {110780S},
abstract = {Optical coherence tomography (OCT) applications like ultra-widefield and full eye-length imaging are of high interest for various diagnostic purposes. In swept-source OCT these techniques require a swept light source, which is coherent over the whole imaging depth. We present a zero roll-off 1060 nm Fourier Domain Mode Locked-Laser (FDML-Laser) for retinal OCT imaging at 1.7 MHz A-scan rate and first long-range imaging results with it. Several steps such as improved dispersion compensation and frequency regulation were performed and will be discussed. Besides virtually no loss in OCT signal over the maximum depth range of 4.6 mm and very good dynamic range was observed. Roll-off measurements show no decrease of the point-spread function (PSF), while maintaining a high dynamic range.},
keywords = {optical coherence tomography, OCT, tunable laser, Fourier Domain Mode Locking, FDML, MHz OCT},
year = {2019},
doi = {10.1117/12.2527034},
URL = {https://doi.org/10.1117/12.2527034}
}
Madita Göb, Tom Pfeiffer, and Robert Huber,
Towards combined optical coherence tomography and multi-spectral imaging with MHz a-scan rates for endoscopy, in Optical Coherence Imaging Techniques and Imaging in Scattering Media III , aciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh, Eds. 072019. pp. 110780Y.
DOI:10.1117/12.2526796
Bibtex: BibTeX
@inproceedings{10.1117/12.2526796,
author = {Madita G{\"o}b and Tom Pfeiffer and Robert Huber},
title = {{Towards combined optical coherence tomography and multi-spectral imaging with MHz a-scan rates for endoscopy}},
volume = {11078},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media III},
editor = {Maciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {110780Y},
abstract = {We demonstrate a preliminary setup of a combined MHz-OCT and RGB narrowband reflection microscope and investigate the performance of the new RGB branch and different display modes of colored OCT data sets.},
keywords = {MHz OCT, multi-spectral imaging, Optical Coherence Tomography, Fourier Domain Mode Locked , FDML, RGB, Color },
year = {2019},
doi = {10.1117/12.2526796},
URL = {https://doi.org/10.1117/12.2526796}
}
Yoko Miura, Wolfgang Draxinger, Christin Grill, Tom Pfeiffer, Salvatore Grisanti, and Robert Huber,
MHz-OCT for low latency virtual reality guided surgery: first wet lab experiments on ex-vivo porcine eye, in Optical Coherence Imaging Techniques and Imaging in Scattering Media III , Maciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh, Eds. SPIE, 072019. pp. 110780E.
DOI:10.1117/12.2527123
Bibtex: BibTeX
@inproceedings{10.1117/12.2527123,
author = {Yoko Miura and Wolfgang Draxinger and Christin Grill and Tom Pfeiffer and Salvatore Grisanti and Robert Huber},
title = {{MHz-OCT for low latency virtual reality guided surgery: first wet lab experiments on ex-vivo porcine eye
}},
volume = {11078},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media III},
editor = {Maciej Wojtkowski and Stephen A. Boppart and Wang-Yuhl Oh},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {110780E},
abstract = {MHz-OCT systems based on FDML swept laser sources combined with the massive parallel processing capabilities of modern computer hardware enable volumetric imaging, processing and stereoscopic display at video rates. The increasing image quality and speed might enable new fields of application where the volumetric OCT completely replaces stereoscopic microscopes instead of being a mere supplement. Aside from the depth resolving capability, a particular advantage is the ability to display a whole image volume from arbitrary points of view without the need to move the actual microscope or to rotate the patient’s eye. Purely digital microscopy is already offered as alternative to traditional through-an-eyepiece surgical microscope. We explore the use of virtual reality to present digital OCT microscopy images to a trained surgeon, carrying out a series of surgical procedures ex-vivo on a porcine eye model.},
keywords = {virtual reality, surgery guidance , real-time OCT, user experience},
year = {2019},
doi = {10.1117/12.2527123},
URL = {https://doi.org/10.1117/12.2527123}
}
Jan Philip Kolb, Wolfgang Draxinger, Julian Klee, Tom Pfeiffer, Matthias Eibl, Thomas Klein, Wolfgang Wieser, and Robert Huber,
Live video rate volumetric OCT imaging of the retina with multi-MHz A-scan rates, PLOS ONE , vol. 14, no. 7, pp. e0213144, 03 2019.
DOI:10.1371/journal.pone.0213144
Bibtex: BibTeX
@article{Kolb2019,
   author = {Kolb, J P;Draxinger, W;Klee, J;Pfeiffer, T;Eibl, M;Klein, T;Wieser, W and Huber, R},
   title = {Live video rate volumetric OCT imaging of the retina with multi-MHz A-scan rates},
   journal = {J pone},
 keywords = {AG-Huber_OCT},
   url = {https://doi.org/10.1371/journal.pone.0213144},
   pages = {e0213144},
   ISSN = {1932-6203},
   
   year = {2019},
   type = {Journal Article}
}
Dominic Kastner, Torben Blömker, Tom Pfeiffer, Christin Grill, Mark Schmidt, Christian Jirauschek, and Robert Huber,
Measurement of Inter-Sweep Phase Stability of an FDML Laser with a 10 kHz Tunable Ring Laser, in 2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference , Optical Society of America, 2019. pp. 1-1.
DOI:10.1109/CLEOE-EQEC.2019.8872860
Bibtex: BibTeX
@inproceedings{Kastner:19,
author = {Kastner, D; Bl\"{o}mker, T; Pfeiffer, T; Grill, C; Schmidt, M; Jirauschek, C and Huber, R},
booktitle = {2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference},
journal = {2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference},
keywords = {Fourier domain mode locking; Image quality; Optical coherence tomography; Phase noise; Ring lasers; Tunable lasers},
pages = {cj_7_5},
publisher = {Optical Society of America},
title = {Measurement of Inter-Sweep Phase Stability of an FDML Laser with a 10 kHz Tunable Ring Laser},
year = {2019},
keywords = {AG-Huber_FDML, AG-Huber_OCT},
doi = { 10.1109/CLEOE-EQEC.2019.8872860},
abstract = {Fourier Domain Mode Locking (FDML) lasers are light sources that generate a sequence of narrowband optical frequency sweeps at the fundamental or harmonic of the cavity repetition rate \[1\]. This frequency swept output can also be considered as a sequence of strongly chirped, long pulses. FDML lasers are mainly used in swept source optical coherence tomography (SS-OCT), a medical imaging technique. The coherence length of the source, i.e. the intra-sweep phase stability of an FDML sweep, is decisive for the image quality and performance of OCT imaging \[2\].},
}

2018

Josef Maertz, Jan Philip Kolb, Thomas Klein, Kathrin J. Mohler, Matthias Eibl, Wolfgang Wieser, Robert Huber, Siegfried Priglinger, and Armin Wolf,
Combined in-depth, 3D, en face imaging of the optic disc, optic disc pits and optic disc pit maculopathy using swept-source megahertz OCT at 1050 nm, Graefes Arch Clin Exp Ophthalmol , vol. 256, no. 2, pp. 289-298, Dec. 2018.
DOI:10.1007/s00417-017-3857-9
Bibtex: BibTeX
@article{Maertz2018,
   author = {Maertz, J; Kolb, J P; Klein, T; Mohler, K J; Eibl, M; Wieser, W; Huber, R; Priglinger, S and Wolf, A},
   title = {Combined in-depth, 3D, en face imaging of the optic disc, optic disc pits and optic disc pit maculopathy using swept-source megahertz OCT at 1050 nm},
   journal = {Graefe's Archive for Clinical and Experimental Ophthalmology},
   number = {2},
   pages = {289-298},
   DOI = {10.1007/s00417-017-3857-9},
   url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85032262413&doi=10.1007%2fs00417-017-3857-9&partnerID=40&md5=a46c315f12cf5e633ea0f7e644116eb3},
   year = {2018},
   Keywords= {En face imaging, Optical coherence tomography, Swept-source OCT, Megahertz OCT, 3D rendering, Optic disc, Optic disc pit, Optic disc pit maculopathy, AG-Huber_OCT},
   type = {Journal Article}
}
Hinnerk Schulz-Hildebrandt, Tom Pfeiffer, Tim Eixmann, Sabrina Lohmann, Martin Ahrens, Josua Rehra, Wolfgang Draxinger, Peter König, Robert Huber, and Gereon Hüttmann,
High-speed fiber scanning endoscope for volumetric multi-megahertz optical coherence tomography, Opt. Lett. , vol. 43, no. 18, pp. 4386-4389, 09 2018. Optica Publishing Group.
DOI:10.1364/OL.43.004386
Bibtex: BibTeX
@article{Schulz-Hildebrandt:18,
author = {Hinnerk Schulz-Hildebrandt and Tom Pfeiffer and Tim Eixmann and Sabrina Lohmann and Martin Ahrens and Joshua Rehra and Wolfgang Draxinger and Peter K\"{o}nig and Robert Huber and Gereon H\"{u}ttmann},
journal = {Opt. Lett.},
keywords = {Fiber optics imaging; Endoscopic imaging; Medical and biological imaging; Optical coherence tomography; Fourier domain mode locking; Image quality; Optical coherence tomography; Single mode fibers; Step index fibers; Three dimensional imaging},
number = {18},
pages = {4386--4389},
publisher = {Optica Publishing Group},
title = {High-speed fiber scanning endoscope for volumetric multi-megahertz optical coherence tomography},
volume = {43},
month = {Sep},
year = {2018},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-43-18-4386},
doi = {10.1364/OL.43.004386},
abstract = {We present a forward-viewing fiber scanning endoscope (FSE) for high-speed volumetric optical coherence tomography (OCT). The reduction in size of the probe was achieved by substituting the focusing optics by an all-fiber-based imaging system which consists of a combination of scanning single-mode fibers, a glass spacer, made from a step-index multi-mode fiber, and a gradient-index fiber. A lateral resolution of 11 $\mu$m was achieved at a working distance of 1.2 mm. The newly designed piezo-based FSE has an outer diameter of 1.6 mm and a rigid length of 13.5 mm. By moving the whole imaging optic in spirals for scanning the sample, the beam quality remains constant over the entire field of view with a diameter of 0.8 mm. The scanning frequency was adjusted to 1.22 kHz for use with a 3.28 MHz Fourier domain mode locked OCT system. Densely sampled volumes have been imaged at a rate of 6 volumes per second.},
}
Jan Philip Kolb, Tom Pfeiffer, Matthias Eibl, Hubertus Hakert, and Robert Huber,
High-resolution retinal swept source optical coherence tomography with an ultra-wideband Fourier-domain mode-locked laser at MHz A-scan rates, Biomed. Opt. Express , vol. 9, no. 1, pp. 120-130, 01 2018. Optica Publishing Group.
DOI:10.1364/BOE.9.000120
Bibtex: BibTeX
@article{Kolb:18,
author = {Jan Philip Kolb and Tom Pfeiffer and Matthias Eibl and Hubertus Hakert and Robert Huber},
journal = {Biomed. Opt. Express},
keywords = {Medical optics instrumentation; Lasers, fiber; Medical and biological imaging; Ophthalmic optics and devices ; Optical coherence tomography; Adaptive optics; Image quality; In vivo imaging; Mode locking; Ophthalmic imaging; Three dimensional imaging},
number = {1},
pages = {120--130},
publisher = {Optica Publishing Group},
title = {High-resolution retinal swept source optical coherence tomography with an ultra-wideband Fourier-domain mode-locked laser at MHz A-scan rates},
volume = {9},
month = {Jan},
year = {2018},
url = {https://opg.optica.org/boe/abstract.cfm?URI=boe-9-1-120},
doi = {10.1364/BOE.9.000120},
abstract = {We present a new 1060 nm Fourier domain mode locked laser (FDML laser) with a record 143 nm sweep bandwidth at 2\&\#x2219;\&\#x202F;417 kHz\&\#x202F; $=$ \&\#x202F;834 kHz and 120 nm at 1.67 MHz, respectively. We show that not only the bandwidth alone, but also the shape of the spectrum is critical for the resulting axial resolution, because of the specific wavelength-dependent absorption of the vitreous. The theoretical limit of our setup lies at 5.9 \&\#x00B5;m axial resolution. In vivo MHz-OCT imaging of human retina is performed and the image quality is compared to the previous results acquired with 70 nm sweep range, as well as to existing spectral domain OCT data with 2.1 \&\#x00B5;m axial resolution from literature. We identify benefits of the higher resolution, for example the improved visualization of small blood vessels in the retina besides several others.},
}

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, 092017. 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.},
}
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, 082017. 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}
}
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, 082017. 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}
}
Josef Maertz, Kathrin J. Mohler, Jan Philip Kolb, Thomas Klein, Aljoscha Neubauer, Anselm Kampik, Siegfried Priglinger, Wolfgang Wieser, Robert Huber, and Armin Wolf,
INTRAPAPILLARY PROLIFERATION IN OPTIC DISK PITS: Clinical Findings and Time-Related Changes, Retina , vol. 37, no. 5, pp. 906-914, 05 2017.
DOI:10.1097/iae.0000000000001260
Bibtex: BibTeX
@article{Maertz2017,
   author = {Maertz, J. and Mohler, K. J. and Kolb, J. P. and Klein, T. and Neubauer, A. and Kampik, A. and Priglinger, S. and Wieser, W. and Huber, R. and Wolf, A.},
   title = {INTRAPAPILLARY PROLIFERATION IN OPTIC DISK PITS: Clinical Findings and Time-Related Changes},
   journal = {Retina},
   volume = {37},
   number = {5},
   pages = {906-914},
   DOI = {10.1097/iae.0000000000001260},
   year = {2017},
keywords = {AG-Huber_OCT},
   type = {Journal Article}
}
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, 032017. 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}
}
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, 022017. 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}
}
Thomas Klein, and Robert Huber,
High-speed OCT light sources and systems [Invited], Biomed. Opt. Express , vol. 8, no. 2, pp. 828-859, 02 2017. Optica Publishing Group.
DOI:10.1364/BOE.8.000828
Bibtex: BibTeX
@article{Klein:17,
author = {Thomas Klein and Robert Huber},
journal = {Biomed. Opt. Express},
keywords = {Imaging systems; Optical coherence tomography; Lasers and laser optics; Lasers, tunable; Optical coherence tomography; Full field optical coherence tomography; High speed imaging; Image quality; Imaging systems; Light wavelength; X ray imaging},
number = {2},
pages = {828--859},
publisher = {Optica Publishing Group},
title = {High-speed OCT light sources and systems \[Invited\]},
volume = {8},
month = {Feb},
year = {2017},
url = {https://opg.optica.org/boe/abstract.cfm?URI=boe-8-2-828},
doi = {10.1364/BOE.8.000828},
abstract = {Imaging speed is one of the most important parameters that define the performance of optical coherence tomography (OCT) systems. During the last two decades, OCT speed has increased by over three orders of magnitude. New developments in wavelength-swept lasers have repeatedly been crucial for this development. In this review, we discuss the historical evolution and current state of the art of high-speed OCT systems, with focus on wavelength swept light sources and swept source OCT systems.},
}
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}
}

2016

Tianshi Wang, Tom Pfeiffer, Evelyn Regar, Wolfgang Wieser, Heleen van Beusekom, Charles T. Lancee, Geert Springeling, Ilona Krabbendam-Peters, Antonius F. W. van der Steen, Robert Huber, and Gijs van Soest,
Heartbeat OCT and Motion-Free 3D In Vivo Coronary Artery Microscopy, JACC: Cardiovascular Imaging , vol. 9, no. 5, pp. 622-623, 2016.
DOI:10.1016/j.jcmg.2015.08.010
Bibtex: BibTeX
@article{WANG2016622,
title = {Heartbeat OCT and Motion-Free 3D In Vivo Coronary Artery Microscopy},
journal = {JACC: Cardiovascular Imaging},
volume = {9},
number = {5},
pages = {622-623},
year = {2016},
issn = {1936-878X},
doi = {https://doi.org/10.1016/j.jcmg.2015.08.010},
url = {https://www.sciencedirect.com/science/article/pii/S1936878X15006713},
author = {Tianshi Wang and Tom Pfeiffer and Evelyn Regar and Wolfgang Wieser and Heleen {van Beusekom} and Charles T. Lancee and Geert Springeling and Ilona Krabbendam-Peters and Antonius F.W. {van der Steen} and Robert Huber and Gijs {van Soest}}
}
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}
}

2015

Tianshi Wang, Tom Pfeiffer, Evelyn Regar, Wolfgang Wieser, Heleen van Beusekom, Charles T. Lancee, Geert Springeling, Ilona Krabbendam, Antonius F. W. van der Steen, Robert Huber, and Gijs van Soest,
Heartbeat OCT: in vivo intravascular megahertz-optical coherence tomography, Biomed. Opt. Express , vol. 6, no. 12, pp. 5021-5032, Dec. 2015. Optica Publishing Group.
DOI:10.1364/BOE.6.005021
Bibtex: BibTeX
@article{Wang:15,
author = {Tianshi Wang and Tom Pfeiffer and Evelyn Regar and Wolfgang Wieser and Heleen van Beusekom and Charles T. Lancee and Geert Springeling and Ilona Krabbendam and Antonius F.W. van der Steen and Robert Huber and Gijs van Soest},
journal = {Biomed. Opt. Express},
keywords = {Fiber optics imaging; Three-dimensional image acquisition; Medical optics instrumentation; Scanners; Endoscopic imaging; Medical and biological imaging; Optical coherence tomography; Image quality; Image registration; Imaging techniques; Laser modes; Mode locking; Optical coherence tomography},
number = {12},
pages = {5021--5032},
publisher = {Optica Publishing Group},
title = {Heartbeat OCT: in vivo intravascular megahertz-optical coherence tomography},
volume = {6},
month = {Dec},
year = {2015},
url = {https://opg.optica.org/boe/abstract.cfm?URI=boe-6-12-5021},
doi = {10.1364/BOE.6.005021},
abstract = {Cardiac motion artifacts, non-uniform rotational distortion and undersampling affect the image quality and the diagnostic impact of intravascular optical coherence tomography (IV-OCT). In this study we demonstrate how these limitations of IV-OCT can be addressed by using an imaging system that we called \&\#x201C;Heartbeat OCT\&\#x201D;, combining a fast Fourier Domain Mode Locked laser, fast pullback, and a micromotor actuated catheter, designed to examine a coronary vessel in less than one cardiac cycle. We acquired in vivo data sets of two coronary arteries in a porcine heart with both Heartbeat OCT, working at 2.88 MHz A-line rate, 4000 frames/s and 100 mm/s pullback speed, and with a commercial system. The in vivo results show that Heartbeat OCT provides faithfully rendered, motion-artifact free, fully sampled vessel wall architecture, unlike the conventional IV-OCT data. We present the Heartbeat OCT system in full technical detail and discuss the steps needed for clinical translation of the technology.},
}
Kathrin J. Mohler, Wolfgang Draxinger, Thomas Klein, Jan Philip Kolb, Wolfgang Wieser, Christos Haritoglou, Anselm Kampik, James G. Fujimoto, Aljoscha Neubauer, Armin Wolf, and Robert Huber,
Combined 60° Wide-Field Choroidal Thickness Maps and High-Definition En Face Vasculature Visualization Using Swept-Source Megahertz OCT at 1050 nm60° High-Definition MHz-OCT Imaging of the Choroid, Investigative Ophthalmology & Visual Science , vol. 56, no. 11, pp. 6284--6293, Oct. 2015.
DOI:10.1167/iovs.15-16670
Bibtex: BibTeX
@article{10.1167/iovs.15-16670,
    author = {Mohler, Kathrin J. and Draxinger, Wolfgang and Klein, Thomas and Kolb, Jan Philip and Wieser, Wolfgang and Haritoglou, Christos and Kampik, Anselm and Fujimoto, James G. and Neubauer, Aljoscha S. and Huber, Robert and Wolf, Armin},
    title = "{Combined 60° Wide-Field Choroidal Thickness Maps and High-Definition En Face Vasculature Visualization Using Swept-Source Megahertz OCT at 1050 nm}",
    journal = {Investigative Ophthalmology & Visual Science},
    volume = {56},
    number = {11},
    pages = {6284-6293},
    year = {2015},
    month = {10},
    abstract = "{   To demonstrate ultrahigh-speed swept-source optical coherence tomography (SS-OCT) at 1.68 million A-scans/s for choroidal imaging in normal and diseased eyes over a ∼60° field of view. To investigate and correlate wide-field three-dimensional (3D) choroidal thickness (ChT) and vascular patterns using ChT maps and coregistered high-definition en face images extracted from a single densely sampled Megahertz-OCT (MHz-OCT) dataset.    High-definition, ∼60° wide-field 3D datasets consisting of 2088 × 1024 A-scans were acquired using a 1.68 MHz prototype SS-OCT system at 1050 nm based on a Fourier-domain mode-locked laser. Nine subjects (nine eyes) with various chorioretinal diseases or without ocular pathology are presented. Coregistered ChT maps, choroidal summation maps, and depth-resolved en face images referenced to either the retinal pigment epithelium or the choroidal–scleral interface were generated using manual segmentation.    Wide-field ChT maps showed a large inter- and intraindividual variance in peripheral and central ChT. In only four of the nine eyes, the location with the largest ChT was coincident with the fovea. The anatomy of the large lumen vessels of the outer choroid seems to play a major role in determining the global ChT pattern. Focal ChT changes with large thickness gradients were observed in some eyes.    Different ChT and vascular patterns could be visualized over ∼60° in patients for the first time using OCT. Due to focal ChT changes, a high density of thickness measurements may be favorable. High-definition depth-resolved en face images are complementary to cross sections and thickness maps and enhance the interpretation of different ChT patterns.  }",
    issn = {1552-5783},
    doi = {10.1167/iovs.15-16670},
    url = {https://doi.org/10.1167/iovs.15-16670},
    eprint = {https://arvojournals.org/arvo/content\_public/journal/iovs/934564/i1552-5783-56-11-6284.pdf},
}
Lukas Reznicek, Jan Philip Kolb, Thomas Klein, Kathrin J. Mohler, Wolfgang Wieser, Robert Huber, Marcus Kernt, Josef Märtz, and Aljoscha Neubauer,
Wide-Field Megahertz OCT Imaging of Patients with Diabetic Retinopathy, Journal of Diabetes Research , vol. 2015, pp. 305084, 07 2015. Hindawi Publishing Corporation.
DOI:10.1155/2015/305084
Bibtex: BibTeX
@article{Reznicek2015,
   author = {Reznicek, Lukas and Kolb, Jan P. and Klein, Thomas and Mohler, Kathrin J. and Wieser, Wolfgang and Huber, Robert and Kernt, Marcus and Märtz, Josef and Neubauer, Aljoscha S.},
   title = {Wide-Field Megahertz OCT Imaging of Patients with Diabetic Retinopathy},
   journal = {Journal of Diabetes Research},
   volume = {2015, Article ID 305084},
   pages = {1-5},
   DOI = {10.1155/2015/305084},
   url = {http://dx.doi.org/10.1155/2015/305084},
   year = {2015},
keywords = {AG-Huber_OCT},
   type = {Journal Article}

}