@inproceedings{10.1117/12.3000908,
author = {Alexander Altmann and Christian Schell and Ramtin Rahmanzadeh},
title = {{Assessing food degradation and microbial growth by sensor read-out with fluorescence spectroscopy}},
volume = {12861},
booktitle = {Frontiers in Biological Detection: From Nanosensors to Systems XVI},
editor = {Amos Danielli and Benjamin L. Miller and Sharon M. Weiss},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {128610A},
abstract = {Both the waste of edible food and the consumption of non-edible food within the best before date are ongoing concerns in food industry. Until now, no methods are applied to access food quality of packed food without opening of packages. We demonstrate the formulation of a sensor foil comprising of a non-toxic porphyrin on an inorganic matrix in polyethylene. The sensor foil is capable of detecting amines in the gas phase over food products, which could act as spoilage indicators during the shelf life of packaged food. The foil was optimized to prevent reactions with other analytes in the gas phase of food by the alteration of the hydrophobic polymer. We performed experiments, using model packing units, to monitor the behavior of the foil and correlated the change in the fluorescence spectra to the total viable count of bacteria on the fish. The readout of the foils was performed with fluorescence spectroscopy to yield highly accurate results in contrast to less accurate the colorimetric determination.},
keywords = {fluorescence spectroscopy, gas sensing, amine sensor, food safety, porphyrins},
year = {2024},
doi = {10.1117/12.3000908},
URL = {https://doi.org/10.1117/12.3000908}
}

@inproceedings{10.1117/12.3000912,
author = {Alexander Altmann and Mohammad Khodaygani and Martin Leucker and Christian Schell and Ramtin Rahmanzadeh},
title = {{Detection of spoiled food along the supply chain with novel sensors for packed food}},
volume = {12879},
booktitle = {Photonic Technologies in Plant and Agricultural Science},
editor = {Dag Heinemann and Gerrit Polder},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1287906},
abstract = {Along food supply chains, several critical steps can lead to inconsumable food. Especially food of animal origin undergoes rapid aging, when stored inadequately. Quality assessment of packaged food products faces serious problems ranging from the loss of integrity of the package to damage of the food and it is applied only to a low number of samples per batch. As a result, food products are either wasted or not analyzed, which results in a significant decrease in food safety. As a part of an intelligent packaging system, we designed a sensor foil that can detect amines, produced during the food aging process. Change of the fluorescence of the sensor foil can be assessed with spectroscopy or color change from green to red can be detected optically with a camera, e.g. by smartphone. The foil can be incorporated inside the single packaging units and noninvasively measured routinely by the store or consumer. The readout of the foils was performed with steady-state tabletop spectrometers, which were then compared to the results for readouts with different inexpensive handheld devices that could be used during real-life applications, e.g., at any step in a food supply chain.  Ideally, the single food product is linked to a single foil at the primary producer, measuring the first spectrum and connecting the data to the specific product, e.g. via distributed ledger. For a transparent process chain, QR-codes could be utilized to allow access to the freshness data along the shelf life of a single package. },
keywords = {fluorescence spectroscopy, gas sensing, amine sensor, food safety, porphyrins, SVM classifier, block chain, non-destructive food testing},
year = {2024},
doi = {10.1117/12.3000912},
URL = {https://doi.org/10.1117/12.3000912}
}

@inproceedings{10.1117/12.3005413,
author = {Noah Heldt and Cornelia Holzhausen and Martin Ahrens and Mario Pieper and Peter K{\"o}nig and Gereon H{\"u}ttmann},
title = {{Improved image quality in dynamic OCT imaging by reduced imaging time and machine learning based data evaluation}},
volume = {PC12830},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVIII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {PC128302A},
abstract = {Dynamic Optical Coherence Tomography combines high resolution tomographic imagery with a cell specific contrast by Fourier analysis. However, the conversion from frequency space into RGB images by binning requires a priori knowledge and artifacts due to global movements provide another obstacle for in vivo application.
We could show that an automated binning based on the Neural Gas algorithm can yield the highest spectral contrast without a priori knowledge and that motion artifacts can be reduced with shorter sequence lengths. Imaging murine airways, we observed that even just 6 frames are enough to generate dOCT images without losing important image information.},
keywords = {Dynamic OCT, Optical Coherence Tomography, Airways, Artificial Intelligence},
year = {2024},
doi = {10.1117/12.3005413},
URL = {https://doi.org/10.1117/12.3005413}
}

@inproceedings{10.1117/12.3005716,
author = {Gereon Hüttmann},
title = {Mathematical model for separating signal and noise in dynamic optical coherence tomography (dOCT)},
volume = {PC12830},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVIII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {PC1283029},
abstract = {Dynamic optical coherence tomography (dOCT) uses signal fluctuation for contrasting different cellular and acellular components in living biological tissue. The autocorrelation or Fourier transform of time series of OCT measurements are converted to a color contrast. However, a quantitative analysis is still challenging. Here we investigate theoretically, how noise of the OCT measurement influences the fluctuation spectra. Probability functions are derived for the different components in the spectra and validated by numerical simulation. With an appropriate calibration of the OCT device a separation of OCT noise and a quantification the dynamic OCT should be feasible.},
keywords = {Optical coherence tomography (OCT), Dynamic optical coherence tomography (OCT), Signal to noise, Speckle statistics, Quantification},
year = {2024},
doi = {10.1117/12.3005716},
URL = {https://doi.org/10.1117/12.3005716}
}

@inproceedings{10.1117/12.2670907,
author = {Paul Strenge and Birgit Lange and Wolfgang Draxinger and Christian Hagel and Christin Grill and Veit Danicke and Dirk Theisen-Kunde and Sonja Spahr-Hess and Matteo M. Bonsanto and Robert Huber and Heinz Handels and Ralf Brinkmann},
title = {{Demarcation of brain and tumor tissue with optical coherence tomography using prior neural networks}},
volume = {12632},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media V},
editor = {Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {126321P},
keywords = {Brain Tumor, OCT, Optical Coherence Tomography, Prior Network, Glioblastoma Multiforme, Neural Network, Classification},
year = {2023},
doi = {10.1117/12.2670907},
URL = {https://doi.org/10.1117/12.2670907}
}

@inproceedings{10.1117/12.2670953,
author = {Wolfgang Draxinger and Dirk Theisen-Kunde and Lion Schuetz and Nicolas Detrez and Paul Strenge and Maximilian Rixius and Veit Danicke and Wolfgang Wieser and Jessica Kren and Patrick Kuppler and Sonja Spar-Hess and Matteo Mario Bonsanto M.D. and Ralf Brinkmann and Robert Huber},
title = {{Microscope integrated realtime high density 4D MHz-OCT in neurosurgery: a depth and tissue resolving visual contrast channel and the challenge of fused presentation}},
volume = {12627},
booktitle = {Translational Biophotonics: Diagnostics and Therapeutics III},
editor = {Zhiwei Huang and Lothar D. Lilge},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {126270W},
abstract = {Microscope integrated realtime 4D MHz-OCT operating at high scanning densities are capable of capturing additional visual contrast resolving depth and tissue. Even within a plain C-scan en-face projection structures are recognizable, that are not visible in a white light camera image. With advanced post processing methods, such as absorbtion coefficient mapping, and morphological classifiers more information is extraced. Presentation to the user in an intuitive way poses practical challenges that go beyond the implementation of a mere overlay display. We present our microscope integrated high speed 4D OCT imaging system, its clinical study use for in-vivo brain tissue imaging, and user feedback on the presentation methods we developed.},
keywords = {optical coherence tomography, neurosurgery, tissue contrast, image fusion, surgical guidance, theranostics},
year = {2023},
doi = {10.1117/12.2670953},
URL = {https://doi.org/10.1117/12.2670953}
}

@inproceedings{10.1117/12.2670957,
author = {Sazgar Burhan and Nicolas Detrez and Madita G{\"o}b and Matteo Mario Bonsanto and Ralf Brinkmann and Robert Huber},
title = {{Advanced FFT-based contrast approach for MHz optical coherence elastography}},
volume = {12632},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media V},
editor = {Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1263215},
abstract = {Optical coherence elastography represents mechanical characteristics of biological tissue in so-called mechanical contrast maps. In addition to the standard intensity image, the contrast map illustrates numerous mechanical tissue features that would otherwise be undetectable. This is of great interest as abnormal physiological changes influence the mechanical behavior of the tissue. We demonstrate an advanced mechanical contrast approach based on the phase signal of our 3.2 MHz optical coherence tomography system. The robustness and performance of this contrast approach is evaluated and discussed based on preliminary results. },
keywords = {Optical Coherence Tomography, OCT, Megahertz OCT, Fourier Domain Mode Locking, Optical Coherence Elastography, OCE, Phase-sensitive OCT, Biomechanics},
year = {2023},
doi = {10.1117/12.2670957},
URL = {https://doi.org/10.1117/12.2670957}
}

@inproceedings{10.1117/12.2670950,
author = {Madita G{\"o}b and Simon Lotz and Linh Ha-Wissel and Sazgar Burhan and Sven B{\"o}ttger and Floris Ernst and Jennifer Hundt and Robert Huber},
title = {{Advances in large area robotically assisted OCT (LARA-OCT): towards drive-by continuous motion imaging}},
volume = {12632},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media V},
editor = {Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {126321N},
abstract = {Optical coherence tomography is a powerful imaging technique to visualize and localize depth-dependent tissue structure to differentiate between healthy and pathological conditions. However, conventional OCT systems are only capable of detecting small areas. To overcome this limitation, we have developed a large area robotically assisted OCT (LARA-OCT) system for automatic acquisition of large OCT images. Using mosaic pattern acquisition and subsequent stitching, we previously demonstrated initial in vivo OCT skin images beyond 10 cm². To improve acquisition speed and reduce dead times, we here demonstrate and analyze LARA-OCT with a new drive-by continuous motion imaging protocol.},
keywords = {Optical Coherence Tomography, Fourier Domain Mode Locking, Robotically Assisted Imaging Systems, Three-dimensional image acquisition, Large Area Scanning, Skin Imaging, OCT, FDML},
year = {2023},
doi = {10.1117/12.2670950},
URL = {https://doi.org/10.1117/12.2670950}
}

@INPROCEEDINGS{10231419,
  author={Lotz, Simon and Göb, Madita and Draxinger, Wolfgang and Dick, Anneli and Huber, Robert},
  booktitle={2023 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)}, 
  title={13.4 MHz FDML Laser for Intra-Surgical Optical Coherence Tomography}, 
  year={2023},
  volume={},
  number={},
  pages={1-1},
  doi={10.1109/CLEO/Europe-EQEC57999.2023.10231419}}

@INPROCEEDINGS{10232141,
  author={Lamminger, Philipp and Hakert, Hubertus and Lotz, Simon and Kolb, Jan Philip and Kutscher, Tonio and Karpf, Sebastian and Huber, Robert},
  booktitle={2023 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)}, 
  title={Four-Wave Mixing Fast Wavelength Sweeping FDML Laser with kW Peak Power at 900 nm and 1300 nm}, 
  year={2023},
  volume={},
  number={},
  pages={1-1},
  doi={10.1109/CLEO/Europe-EQEC57999.2023.10232141}}

@INPROCEEDINGS{10232019,
  author={Klufts, M. and Lotz, S. and Bashir, M. A. and Pfeiffer, T. and Mlynek, A. and Wieser, W. and Chamorovskiy, A. and Shidlovski, V. and Podoleanu, A. and Huber, R.},
  booktitle={2023 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)}, 
  title={Dual Amplification 850 nm FDML Laser}, 
  year={2023},
  volume={},
  number={},
  pages={1-1},
  doi={10.1109/CLEO/Europe-EQEC57999.2023.10232019}}

@INPROCEEDINGS{10232661,
  author={Bashir, M. A. and Lotz, S. and Kluftsa, M. and Jirauschek, C. and Huberab, R.},
  booktitle={2023 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)}, 
  title={1190 nm FDML laser: Challenges and Strategies}, 
  year={2023},
  volume={},
  number={},
  pages={1-1},
  doi={10.1109/CLEO/Europe-EQEC57999.2023.10232661}}

@inproceedings{10.1117/12.2648505,
author = {Wolfgang Draxinger and Dirk Theisen-Kunde and Lion Sch{\"u}tzeck and Nicolas Detrez and Paul Strenge and Veit Danicke and Jessica Kren and Patrick Kuppler and Sonja Spahr-Hess and Matteo Mario Bonsanto and Ralf Brinkmann and Robert Huber},
title = {{High speed 4D in-vivo OCT imaging of the human brain: creating high density datasets for machine learning toward identification of malign tissue in real time}},
volume = {12390},
booktitle = {High-Speed Biomedical Imaging and Spectroscopy VIII},
editor = {Kevin K. Tsia and Keisuke Goda},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {123900D},
abstract = {Neuro-surgery is challenged by the difficulties of determining brain tumor boundaries during excisions. Optical coherence tomography is investigated as an imaging modality for providing a viable contrast channel. Our MHz-OCT technology enables rapid volumetric imaging, suitable for surgical workflows. We present a surgical microscope integrated MHz-OCT imaging system, which is used for the collection of in-vivo images of human brains, with the purpose of being used in machine learning systems that shall be trained to identify and classify tumorous tissue.},
keywords = {optical coherence tomography, brain tumor, neurosurgery, machine learning, contrast augmentation, histology dataset, clinical study, in-vivo imaging},
year = {2023},
doi = {10.1117/12.2648505},
URL = {https://doi.org/10.1117/12.2648505}
}

@inproceedings{10.1117/12.2649646,
author = {M. Klufts and S. Lotz and M. A. Bashir and T. Pfeiffer and A. Mlynek and W. Wieser and A. Chamorovskiy and V. Shidlovski and R. Huber},
title = {{850 nm FDML: performance and challenges}},
volume = {12367},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1236705},
abstract = {We demonstrate a Fourier domain mode locked (FDML) laser centered around 850 nm with a sweeping range of 50 nm, a fundamental repetition rate of 2×416 kHz and an output power of 2 mW. A new cavity design using three chirped Fiber Bragg gratings is required to overcome sweeping limitations caused by high dispersion. Other solutions to address challenges such as high loss and high polarization mode dispersion will be discussed along with performance. A main application of this laser will be retinal imaging, but it might also be applicable for TiCo-Raman and SLIDE microscopy. },
keywords = {Swept source, FDML, Laser, Ophthalmic imaging, OCT, 800 nm, retinal imaging, light sources},
year = {2023},
doi = {10.1117/12.2649646},
URL = {https://doi.org/10.1117/12.2649646}
}

@inproceedings{10.1117/12.2652884,
author = {M. A. Bashir and S. Lotz and M. Klufts and I. Krestnikov and C. Jirauschek and R. Huber},
title = {{1190 nm Fourier domain mode locked (FDML) laser for optical coherence tomography (OCT)}},
volume = {12367},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1236707},
abstract = {We demonstrate a Fourier domain mode locked (FDML) laser centered at 1190 nm with 2×410 kHz sweep repetition rate, a sweeping range of 100 nm and 2.5 mW output power. The laser is based on a quantum dot-semiconductor optical amplifier with small linewidth enhancement factor. The laser could be used as a probe laser in stimulated Raman scattering microscopy and it may be attractive for optical coherence tomography due to low water absorption and the spectral signature of lipids around 1200nm. Moreover, it is ideal to close the gap between FDML lasers at 1064 nm and 1300 nm. Combining these three lasers can enable ultrawideband sweeping to improve the axial OCT resolution down to 2 μm. },
keywords = {FDML, Swept source, laser, SS-OCT, OCT, Tunable lasers},
year = {2023},
doi = {10.1117/12.2652884},
URL = {https://doi.org/10.1117/12.2652884}
}

@inproceedings{10.1117/12.2652955,
author = {Awanish Pratap Singh and Madita G{\"o}b and Martin Ahrens and Tim Eixmann and Hinnerk Schulz-Hildebrandt and Gereon H{\"u}ttmann and Robert Huber and Maik Rahlves},
title = {{Synchronous high-speed OCT imaging with sensor less brushless DC motor and FDML laser in a phase-locked loop}},
volume = {12367},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1236703},
abstract = {High-speed endoscopic optical coherence tomography (OCT) imaging in the MHz range has shown great potential in various medical applications ranging from cancer screening to vascular disease monitoring. High-speed imaging always suffers from non-uniform rotational distortion (NURD) due to asynchronous motor rotation with the OCT system. Several research groups have previously attempted to solve this problem, using either an expensive motor with a sensor or numerical correction after data acquisition. However, both techniques pose challenges for practical use. Therefore, in this study, we use an inexpensive sensorless brushless DC motor with a Fourier domain mode-locked (FDML) laser-based MHz OCT system and try to resolve the problem of synchronization using three different modalities, (i) Slave-mode: The FDML frequency serves as a master frequency for the motor, which is phase-locked to the FDML frequency, (ii) Master-mode: The revolution trigger obtained from the motor’s back electromotive force (BEMF) signal serves as a trigger signal for the OCT imaging system, (iii) Both: Fully synchronized setup, where the motor rotation is synchronized with the laser and the imaging system is synchronized with the motor to achieve phase-stable OCT imaging. The first case slightly fluctuates in live preview and imaging due to the absence of a revolution trigger, while the second has varying motor speeds. Therefore, we use the third case to phase-lock the motor with FDML and get a distortion-free live preview and image acquisition. Finally, we demonstrate high-speed SS-OCT structural imaging (at 3.3 MHz A-scan rates) of a finger with a 16 mm diameter probe (at 40,000 rpm).},
keywords = {Optical Coherence Tomography, Endoscopy, FDML , Closed Loop Motor Control, NURD compensation, Brushless DC Motor, Back Electromotive Force},
year = {2023},
doi = {10.1117/12.2652955},
URL = {https://doi.org/10.1117/12.2652955}
}

@inproceedings{10.1117/12.2648301,
author = {Sazgar Burhan and Nicolas Detrez and Katharina Rewerts and Madita G{\"o}b and Christian Hagel and Matteo Mario Bonsanto and Dirk Theisen-Kunde and Robert Huber and Ralf Brinkmann},
title = {{Characterization of brain tumor tissue by time-resolved, phase-sensitive optical coherence elastography at 3.2 MHz line rate}},
volume = {12368},
booktitle = {Advanced Biomedical and Clinical Diagnostic and Surgical Guidance Systems XXI},
editor = {Caroline Boudoux and James W. Tunnell},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {123680F},
abstract = {Optical coherence elastography (OCE) offers the possibility of obtaining the mechanical behavior of a tissue. When also  using a non-contact mechanical excitation, it mimics palpation without interobserver variability. One of the most frequently  used techniques is phase-sensitive OCE. Depending on the system, depth-resolved changes in the sub-µm to nm range can  be detected and visualized volumetrically. Such an approach is used in this work to investigate and detect transitions  between healthy and tumorous brain tissue as well as inhomogeneities in the tumor itself to assist the operating surgeon  during tumor resection in the future. We present time-resolved, phase-sensitive OCE measurements on various ex vivo brain tumor samples using an ultra-fast 3.2 MHz swept-source optical coherence tomography (SS-OCT) system with a frame rate of 2.45 kHz. 4 mm line scans are acquired which, in combination with the high imaging speed, allow monitoring and investigation of the sample's behavior in response to the mechanical load. Therefore, an air-jet system applies a 200 ms  short air pulse to the sample, whose non-contact property facilitates the possibility for future in vivo measurements. Since we can temporally resolve the response of the sample over the entire acquisition time, the mechanical properties are evaluated at different time points with depth resolution. This is done by unwrapping the phase data and performing subsequent assessment. Systematic ex vivo brain tumor measurements were conducted and visualized as distribution maps.  The study outcomes are supported by histological analyses and examined in detail.},
keywords = { Optical Coherence Tomography, Optical Coherence Elastography, Phase-sensitive OCT, Fourier Domain Mode Locking, Brain Tumor, Phase Unwrapping, Tissue Characterization, Biomechanics},
year = {2023},
doi = {10.1117/12.2648301},
URL = {https://doi.org/10.1117/12.2648301}
}

@inproceedings{10.1117/12.2649663,
author = {Philipp Lamminger and Hubertus Hakert and Simon Lotz and Jan Philip Kolb and Tonio Kutscher and Sebastian Karpf and Robert Huber},
title = {{900 nm swept source FDML laser with kW peak power}},
volume = {12400},
booktitle = {Fiber Lasers XX: Technology and Systems},
editor = {V.  R. Supradeepa},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {124001I},
abstract = {A wavelength agile 900 nm 2.5 kW peak power fiber laser is created by four-wave mixing (FWM) in a photonic crystal fiber (PCF), while amplifying a 1300 nm Fourier-domain mode-locked (FDML) laser. The FWM process is pumped by a home-built 1064 nm master oscillator power amplifier (MOPA) laser and seeded by a home-built 1300 nm FDML laser, generating high power pulses at wavelengths, where amplification by active fiber media is difficult. The 900 nm pulses have a spectral linewidth of 70 pm, are tunable over 54 nm and have electronic pulse-to-pulse tuning capability. These pulses can be used for nonlinear imaging like two-photon or coherent anti-Stokes Raman microscopy (CARS) microscopy including spectro-temporal laser imaging by diffracted excitation (SLIDE) and time-encoded (Tico) stimulated Raman microscopy.},
keywords = {Fourier domain mode locking,  FDML, Raman, two photon microscopy, SLIDE, 900 nm, fiber laser, photonic crystal fiber, swept source},
year = {2023},
doi = {10.1117/12.2649663},
URL = {https://doi.org/10.1117/12.2649663}
}

@inproceedings{10.1117/12.2652616,
author = {Madita G{\"o}b and Simon Lotz and Linh Ha-Wissel and Sazgar Burhan and Sven B{\"o}ttger and Floris Ernst and Jennifer Hundt and Robert Huber},
title = {{Large area robotically assisted optical coherence tomography (LARA-OCT) for skin imaging with MHz-OCT surface tracking}},
volume = {12367},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {123670C},
abstract = {Optical coherence tomography (OCT) is a powerful imaging technique to non-invasively differentiate between healthy skin and pathological conditions. Unfortunately, commercially available OCT-systems are typically slow and not capable of scanning large areas at reasonable speed. Since skin lesions may extend over several square centimeters, potential inflammatory infiltrates remain undetected. Here, we present large area robotically assisted OCT (LARA-OCT) for skin imaging. Therefor a collaborative robot is combined with an existing, home-built 3.3 MHz-OCT-system and for surface tracking an online probe-to-surface control is implemented which is solely based on the OCT surface signal. It features a combined surface-distance and surface-orientation closed-loop control algorithm, which enables automatic positioning and alignment of the probe across the target while imaging. This allows to acquire coherent OCT images of skin areas beyond 10 cm<sup>2</sup>. },
keywords = {Optical Coherence Tomography, Fourier Domain Mode Locking, Robotically Assisted Imaging Systems, Three-dimensional image acquisition, Large Area Scanning, Skin Imaging , OCT, FDML},
year = {2023},
doi = {10.1117/12.2652616},
URL = {https://doi.org/10.1117/12.2652616}
}

@inproceedings{10.1117/12.2649963,
author = {Paul Strenge and Birgit Lange and Wolfgang Draxinger and Christian Hagel and Christin Grill and Veit Danicke and Dirk Theisen-Kunde and Sonja Spahr-Hess and Matteo M. Bonsanto and Robert Huber and Heinz Handels and Ralf Brinkmann},
title = {{Dual wavelength analysis and classification of brain tumor tissue with optical coherence tomography}},
volume = {12368},
booktitle = {Advanced Biomedical and Clinical Diagnostic and Surgical Guidance Systems XXI},
editor = {Caroline Boudoux and James W. Tunnell},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1236805},
abstract = {The ill-defined tumor borders of glioblastoma multiforme pose a major challenge for the surgeon during tumor resection,  since the goal of the tumor resection is the complete removal, while saving as much healthy brain tissue as possible. In  recent years, optical coherence tomography (OCT) was successfully used to classify white matter from tumor infiltrated  white matter by several research groups. Motivated by these results, a dataset was created, which consisted of sets of  corresponding ex vivo OCT images, which were acquired by two OCT-systems with different properties (e.g. wavelength  and resolution). Each image was annotated with semantic labels. The labels differentiate between white and gray matter  and three different stages of tumor infiltration. The data from both systems not only allowed a comparison of the ability of  a system to identify the different tissue types present during the tumor resection, but also enable a multimodal tissue  analysis evaluating corresponding OCT images of the two systems simultaneously. A convolutional neural network with  dirichlet prior was trained, which allowed to capture the uncertainty of a prediction. The approach increased the sensitivity  of identifying tumor infiltration from 58 % to 78 % for data with a low prediction uncertainty compared to a previous  monomodal approach. },
keywords = {optical coherence tomography, oct, brain, classification, tumor, dual wavelength, glioblastoma multiforme, tissue analysis},
year = {2023},
doi = {10.1117/12.2649963},
URL = {https://doi.org/10.1117/12.2649963}
}

@inproceedings{10.1117/12.2670881,
author = {Dirk Theisen-Kunde and Florian Sommer and Veit Danicke and Lion Sch{\"u}tzeck and Stefan Meyer and Christopher Kren and Maximilian Rixius and Sebastian Karpf},
title = {{Small footprint SLIDE demonstrator for 40Hz volume rate multiphoton microscopy}},
volume = {12630},
booktitle = {Advances in Microscopic Imaging IV},
editor = {Emmanuel Beaurepaire and Adela Ben-Yakar and YongKeun Park},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {126300Q},
keywords = {multiphoton microscopy, flow cytometry, Fourier Domain Mode Locked Laser, SLIDE, kHz- Imaging},
year = {2023},
doi = {10.1117/12.2670881},
URL = {https://doi.org/10.1117/12.2670881}
}

@inproceedings{10.1117/12.2652847,
author = {Sazgar Burhan and Nicolas Detrez and Katharina Rewerts and Madita G{\"o}b and Steffen Buschschl{\"u}ter and Christian Hagel and Matteo Mario Bonsanto M.D. and Dirk Theisen-Kunde and Robert Huber and Ralf Brinkmann},
title = {{Phase analysis strategies for MHz OCE in the large displacement regime}},
volume = {12367},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {123670Q},
abstract = {In neurosurgical tumor operations on the central nervous system, intraoperative haptic information often assists for discrimination between healthy and diseased tissue. Thus, it can provide the neurosurgeon with additional intraoperative source of information during resection, next to the visual information by the light microscope, fluorescent dyes and neuronavigation. One approach to obtain elastic and viscoelastic tissue characteristics non-subjectively is phase-sensitive optical coherence elastography (OCE), which is based on the principle of optical coherence tomography (OCT). While phase-sensitive OCE offers significantly higher displacement sensitivity inside a sample than commonly used intensity-based correlation methods, it requires a reliable algorithm to recover the phase signal, which is mathematically restricted in the -π to π range. This problem of phase wrapping is especially critical for inter-frame phase analysis since the time intervals between two referenced voxels is long. Here, we demonstrate a one-dimensional unwrapping algorithm capable of removing up to 4π-ambiguities between two frames in the complex phase data obtained from a 3.2 MHz-OCT system. The high sampling rate allows us to resolve large sample displacements induced by a 200 ms air pulse and acquires pixel-precise detail information. The deformation behavior of the tissue can be monitored over the entire acquisition time, offering various subsequent mechanical analysis procedures. The reliability of the algorithm and imaging concept was initially evaluated using different brain tumor mimicking phantoms. Additionally, results from human ex vivo brain tumor samples are presented and correlated with histological findings supporting the robustness of the algorithm.},
keywords = {Optical Coherence Tomography, Megahertz OCT, Fourier Domain Mode Locking, Optical Coherence Elastography, Phase-sensitive OCT, Phase Unwrapping, Brain tumor, Biomechanics},
year = {2023},
doi = {10.1117/12.2652847},
URL = {https://doi.org/10.1117/12.2652847}
}