Dr. Madita Göb

@article{Gob:25,
author = {Madita G\"{o}b and Linh Ha-Wissel and Caren Jacobi and Jennifer E. Hundt and Robert Huber},
journal = {Biomed. Opt. Express},
keywords = {Effective refractive index; High speed imaging; Image metrics; Imaging systems; Imaging techniques; In vivo imaging},
number = {10},
pages = {4063--4078},
publisher = {Optica Publishing Group},
title = {Megahertz dynamic optical coherence tomography of blisters in human skin},
volume = {16},
month = {Oct},
year = {2025},
url = {https://opg.optica.org/boe/abstract.cfm?URI=boe-16-10-4063},
doi = {10.1364/BOE.571621},
abstract = {Detecting epidermal blisters in human skin using optical coherence tomography (OCT) is clinically valuable, particularly for diagnosing autoimmune blistering diseases. Dynamic OCT (dOCT) extends conventional structural imaging by providing motion-based contrast sensitive to tissue dynamics. In this study, we analyze the diagnostic potential of dynamic contrast in high-speed (MHz-OCT) and microscopic (mOCT) OCT for blister imaging. We first evaluate whether these systems offer sufficient structural detail for blister detection, comparing them to a clinical reference. Dynamic contrast was then examined in an ex vivo human skin blister model using mOCT, and in vivo, MHz-OCT was subsequently applied to healthy and blistered skin. Our findings demonstrate improved layer delineation and blister localization. We further discuss system-specific image characteristics, artifacts, and their implications for future OCT-based diagnostic workflows.},
}

@article{RN5536,
   author = {Burhan, Sazgar;Göb, Madita;Pieper, Mario;Laedtke, Tjalfe;Grahl, Thorge;Münter, Michael;Schulz-Hildebrandt, Hinnerk;Hüttmann, Gereon;König, Peter and Huber, Robert},
   title = {Label-free volumetric imaging of porcine kidney tissue over extended areas using dynamic MHz-OCT},
   journal = {Scientific Reports},
   volume = {15},
   number = {1},
   pages = {32426},
   ISSN = {2045-2322},
   DOI = {10.1038/s41598-025-15032-6},
   url = {https://doi.org/10.1038/s41598-025-15032-6},
   year = {2025},
   type = {Journal Article}
}

@inproceedings{10.1117/12.3046222,
author = {Sazgar Burhan and Berenice Schulte and Madita G{\"o}b and Awanish Pratap Singh and Bayan Mustafa and Simon Lotz and Wolfgang Draxinger and Philipp Lamminger and Yasmeine Saker and Tim Eixmann and Martin Ahrens and Marvin Heimke and Tillmann Heinze and Thilo Wedel and Maik Rahlves and Mark Ellrichmann and Robert Huber},
title = {{Switchable lateral resolution real-time MHz-OCT rectoscopy for enhanced colorectal disease diagnosis}},
volume = {13305},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIX},
editor = {Rainer A. Leitgeb and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1330512},
abstract = {Endoscopic optical coherence tomography (OCT) offers in vivo live visualization of transmural structures with histological resolution, making it a valuable tool in medical imaging. In gastroenterology, OCT endoscopy is particularly advantageous for assessing rectal wall layers, providing superior axial and lateral resolution compared to conventional rectal endoscopic ultrasound. However, the large diameter and uneven colon surface present challenges for comprehensive imaging. Extending the OCT imaging range addresses this issue by enabling a thorough examination of the entire colon, facilitating the detection of surface polyps, tumors, and their infiltration depth. Once these regions of interest are identified, high-resolution imaging becomes essential for detailed evaluation. To meet these demands, this study integrates two different imaging modes, an extended-range mode, and a high-detail mode, within a rigid rectoscope. The extended-range mode enables visualization of deeper structures, while the high-detail mode enhances image quality for precise, contact-based assessments. The system allows seamless, real-time transitions between the modes using a 3.2MHz-OCT system and a fiber‑optic MEMS switch.},
keywords = {Optical Coherence Tomography, Megahertz OCT, Fourier Domain Mode Locking, Three-dimensional image acquisition, Rectal Imaging, Long-Range Imaging, Non-Invasive Diagnostic Imaging, Tumor Assessment},
year = {2025},
doi = {10.1117/12.3046222},
URL = {https://doi.org/10.1117/12.3046222}
}

@inproceedings{10.1117/12.3046216,
author = {Sazgar Burhan and Madita G{\"o}b and Mario Pieper and Tjalfe Laedtke and Thorge Grahl and Michael M{\"u}nter and Hinnerk Schulz-Hildebrandt and Gereon H{\"u}ttmann and Peter K{\"o}nig and Robert Huber},
title = {{Large-area dynamic contrast MHz optical coherence tomography for label-free imaging of porcine tissue}},
volume = {13305},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIX},
editor = {Rainer A. Leitgeb and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1330502},
abstract = {We demonstrate a 3.2 MHz-OCT system for inter-volumetric dynamic optical coherence tomography of ex vivo porcine kidney tissue. Employing a home-built Fourier Domain mode locking (FDML) laser with a 1310 nm wavelength, the system achieved a lateral resolution of 3.48 μm and a frame rate of 612 Hz. A motorized XYZ positioning stage enabled the precise acquisition of multiple volumes, which were seamlessly stitched together to generate a comprehensive dataset with a total area of 2.6 × 2.6 mm<sup>2</sup>. Validations against histological sections confirmed the system’s ability to visualize cellular tissue structures.},
keywords = {Optical Coherence Tomography, Megahertz OCT, Fourier Domain Mode Locking, Dynamic OCT, Functional OCT, Three-dimensional image acquisition, Tissue Dynamics, Kidney},
year = {2025},
doi = {10.1117/12.3046216},
URL = {https://doi.org/10.1117/12.3046216}
}

@Article{ebj6040054,
author = {Larsen, Beke Sophie and Straube, Tina and Kelly, Kathrin and Huber, Robert and Göb, Madita and Siebert, Julia and Wünsch, Lutz and Lindert, Judith},
title = {Assessment of Attenuation Coefficient and Blood Flow at Depth in Pediatric Thermal Hand Injuries Using Optical Coherence Tomography: A Clinical Study},
journal = {European Burn Journal},
volume = {6},
year = {2025},
number = {4},
article-number = {54},
url = {https://www.mdpi.com/2673-1991/6/4/54},
issn = {2673-1991},
abstract = {Background: Optical Coherence Tomography (OCT) is a high-resolution imaging technique capable of quantifying Blood Flow at Depth (BD) and the Attenuation Coefficient (AC). However, the clinical relevance of these parameters in burn assessment remains unclear. This study investigated whether OCT-derived metrics can differentiate between superficial and deep pediatric hand burns. Method: This prospective, single-center study analyzed 73 OCT scans from 37 children with thermal hand injuries. A structured algorithm was used to evaluate AC and BD. Results: The mean AC was 1.61 mm−1 (SD ± 0.48), with significantly higher values in deep burns (2.11 mm−1 ± 0.53) compared to superficial burns (1.49 mm−1 ± 0.38; p < 0.001), reflecting increased optical density in more severe burns. BD did not differ significantly between burn depths, although superficial burns more often showed visible capillary networks. Conclusions: This is the first study to assess both AC and BD using OCT in pediatric hand burns. AC demonstrated potential as a diagnostic marker for burn depth, whereas BD had limited utility. Image quality limitations highlight the need for technical improvements to enhance OCT’s clinical application.},
doi = {10.3390/ebj6040054}
}

@inproceedings{Gob:25,
author = {Madita G\"{o}b and Sazgar Burhan and Gereon H\"{u}ttmann and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Clinical applications; Imaging techniques; In vivo imaging; Optical coherence tomography; Three dimensional imaging; Tissue characterization},
pages = {Tu3C.4},
publisher = {Optica Publishing Group},
title = {In vivo Megahertz Dynamic Optical Coherence Tomography of Human Skin},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-Tu3C.4},
doi = {10.1364/ECBO.2025.Tu3C.4},
abstract = {We demonstrate Megahertz optical coherence tomography (MHz-OCT) for in vivo skin imaging with dynamic contrast at different resolutions. This study presents recent advances and discusses challenges for clinical translation and real-time in vivo applications.},
}

@inproceedings{Draxinger:25,
author = {Wolfgang Draxinger and Simon Lotz and Allegra Behr and Madita G\"{o}b and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Absolute distance measurement; Field programmable gate arrays; Imaging systems; Light sources; Scanners; Swept sources},
pages = {W5D.5},
publisher = {Optica Publishing Group},
title = {Lifting constraints on multi-kHz raster-line scanning frequency matching in multi-MHz Swept-Source OCT imaging systems},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-W5D.5},
doi = {10.1364/ECBO.2025.W5D.5},
abstract = {The established synchronization scheme of SS-OCT calls for the raster-line frequency to be a remainder-less divider of the sweep frequency. Two methods are presented that increase flexibility in scanner operation.},
}

@inproceedings{Singh:25,
author = {Awanish Pratap Singh and Madita G\"{o}b and Sazgar Burhan and Nikolay Tesmer and Wolfgang Draxinger and Simon Lotz and Berenice Schulte and Mark Ellrichmann and Robert Huber and Maik Rahlves},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Clinical applications; Endoscopic imaging; Imaging systems; Laser sources; Optical components; Three dimensional reconstruction},
pages = {M1C.1},
publisher = {Optica Publishing Group},
title = {Multi-MHz-OCT Endoscopic Imaging with an Automated Pullback Mechanism},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-M1C.1},
doi = {10.1364/ECBO.2025.M1C.1},
abstract = {We present an automated pullback mechanism for MHz-OCT rectoscopy to address non-uniform motion artifacts via consistent probe retraction. High-resolution images of a test sample demonstrate uniform frame spacing, reduced distortion, and improved imaging accuracy, validating its potential for in-vivo clinical applications.},
}

@inproceedings{Burhan:25,
author = {Sazgar Burhan and Madita G\"{o}b and Gereon H\"{u}ttmann and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Imaging techniques; In vivo imaging; Optical coherence tomography; Optical systems; Spatial resolution; Tissue imaging},
pages = {S4B.3},
publisher = {Optica Publishing Group},
title = {Non-Equidistant Temporal Scanning in Dynamic MHz-OCT for Higher Speed},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-S4B.3},
doi = {10.1364/ECBO.2025.S4B.3},
abstract = {We investigate advanced scanning strategies to improve speed in dynamic MHz-OCT, demonstrating that temporally non-uniform sampling outperforms uniform scanning by achieving faster imaging speeds while largely preserving image clarity.},
}

@inproceedings{Laedtke:25,
author = {Tjalfe Laedtke and Sazgar Burhan and Simon Lotz and Madita G\"{o}b and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Image registration; Imaging systems; Phase shift; Spatial resolution; Speckle noise; Speckle patterns},
pages = {W1D.4},
publisher = {Optica Publishing Group},
title = {Speckle Reduction Through Angular Compounding in Robotically Assisted MHz-OCT},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-W1D.4},
doi = {10.1364/ECBO.2025.W1D.4},
abstract = {We demonstrate speckle reduction in robotically assisted MHz-OCT by angular compounding. The robot is used to acquire images from different angles, which, after registration, are used for efficient speckle averaging without loss of spatial resolution.},
}

@article{Lotz:24,
author = {Simon Lotz and Madita G\"{o}b and Sven B\"{o}ttger and Linh Ha-Wissel and Jennifer Hundt and Floris Ernst and Robert Huber},
journal = {Biomed. Opt. Express},
keywords = {Angiography; Biomedical imaging; In vivo imaging; Machine vision; Point clouds; Spectral domain optical coherence tomography},
number = {6},
pages = {3993--4009},
publisher = {Optica Publishing Group},
title = {Large area robotically assisted optical coherence tomography (LARA-OCT)},
volume = {15},
month = {Jun},
year = {2024},
url = {https://opg.optica.org/boe/abstract.cfm?URI=boe-15-6-3993},
doi = {10.1364/BOE.525524},
abstract = {We demonstrate large-area robotically assisted optical coherence tomography (LARA-OCT), utilizing a seven-degree-of-freedom robotic arm in conjunction with a 3.3\&\#x2005;MHz swept-source OCT to raster scan samples of arbitrary shape. By combining multiple fields of view (FOV), LARA-OCT can probe a much larger area than conventional OCT. Also, nonplanar and curved surfaces like skin on arms and legs can be probed. The lenses in the LARA-OCT scanner with their normal FOV can have fewer aberrations and less complex optics compared to a single wide field design. This may be especially critical for high resolution scans. We directly use our fast MHz-OCT for tracking and stitching, making additional machine vision systems like cameras, positioning, tracking or navigation devices obsolete. This also eliminates the need for complex coordinate system registration between OCT and the machine vision system. We implemented a real time probe-to-surface control that maintains the probe alignment orthogonal to the sample by only using surface information from the OCT images. We present OCT data sets with volume sizes of 140\&\#x2009;\&\#x00D7;\&\#x2009;170\&\#x2009;\&\#x00D7;\&\#x2009;20 mm3, captured in 2.5 minutes.},
}

@article{https://doi.org/10.1111/jdv.20097,
author = {Ha-Wissel, L. and Graßhoff, H. and Göb, M. and Mustafa, B. and Huber, R. and Zirpel, H. and Yasak, H. and Thaçi, D. and Hundt, J. E.},
title = {Optical coherence tomography-based imaging biomarkers for disease activity monitoring in plaque psoriasis},
journal = {Journal of the European Academy of Dermatology and Venereology},
volume = {n/a},
number = {n/a},
pages = {},
doi = {https://doi.org/10.1111/jdv.20097},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/jdv.20097},
eprint = {https://onlinelibrary.wiley.com/doi/pdf/10.1111/jdv.20097}
}

@article{10.1093/ecco-jcc/jjae034,
    author = {Ellrichmann, Mark and Schulte, Berenice and Conrad, Claudio C and Schoch, Stephan and Bethge, Johannes and Seeger, Marcus and Huber, Robert and Goeb, Madita and Arlt, Alexander and Nikolaus, Susanna and Röcken, Christoph and Schreiber, Stefan},
    title = "{Contrast enhanced endoscopic ultrasound detects early therapy response following anti-TNF-therapy in patients with ulcerative colitis}",
    journal = {Journal of Crohn's and Colitis},
    pages = {jjae034},
    year = {2024},
    month = {03},
    abstract = "{Though colonoscopy plays a crucial role in assessing active ulcerative colitis (aUC), its scope is limited to the mucosal surface. Endoscopic ultrasound (EUS) coupled with contrast-enhancement (dCEUS) can precisely quantify bowel wall thickness and microvascular circulation, potentially enabling the quantitative evaluation of inflammation.We conducted a prospective, longitudinal study to assess therapy response using dCEUS in aUC patients undergoing treatment with adalimumab (ADA) or infliximab (IFX).30 ADA- and 15 IFX-treated aUC patients were examined at baseline and at 2, 6, 14 weeks of therapy and 48 weeks of follow-up. Bowel wall thickness (BWT) was measured by EUS in the rectum. Vascularity was quantified by dCEUS using Rise Time (RT) and Time To Peak (TTP). Therapy response was defined after 14 weeks using the Mayo Score.Patients with aUC displayed a mean BWT of 3.9±0.9 mm. In case of response to ADA/IFX a significant reduction in BWT was observed after 2 weeks (p=0.04), whereas non-responders displayed no significant changes. The TTP was notably accelerated at baseline and significantly normalised by week 2 in responders (p=0.001), while non-responders exhibited no significant alterations (p=0.9). At week 2, the endoscopic Mayo score did not exhibit any changes, thus failing to predict treatment responses.dCEUS enables the early detection of therapy response in patients with aUC, which serves as a predictive marker for long term clinical success. Therefore, dCEUS serves as a diagnostic tool for assessing the probability of future therapy success.}",
    issn = {1873-9946},
    doi = {10.1093/ecco-jcc/jjae034},
    url = {https://doi.org/10.1093/ecco-jcc/jjae034},
    eprint = {https://academic.oup.com/ecco-jcc/advance-article-pdf/doi/10.1093/ecco-jcc/jjae034/56911128/jjae034.pdf},
}

@article{RN5474,
   author = {Schulte, Berenice;Göb, Madita;Singh, Awanish Pratap;Lotz, Simon;Draxinger, Wolfgang;Heimke, Marvin;pieper, Mario;Heinze, Tillmann;Wedel, Thilo;Rahlves, Maik;Huber, Robert and Ellrichmann, Mark},
   title = {High-resolution rectoscopy using MHz optical coherence tomography: a step towards real time 3D endoscopy},
   journal = {Scientific Reports},
   volume = {14},
   number = {1},
   pages = {4672},
   ISSN = {2045-2322},
   DOI = {10.1038/s41598-024-55338-5},
   url = {https://doi.org/10.1038/s41598-024-55338-5},
   year = {2024},
   type = {Journal Article}
}

@article{Singh:24,
author = {Awanish Pratap Singh and Madita G\"{o}b and Martin Ahrens and Tim Eixmann and Berenice Schulte and Hinnerk Schulz-Hildebrandt and Gereon H\"{u}ttmann and Mark Ellrichmann and Robert Huber and Maik Rahlves},
journal = {Opt. Express},
keywords = {Biomedical imaging; Endoscopic imaging; Imaging systems; Optical coherence tomography; Real time imaging; Vertical cavity surface emitting lasers},
number = {4},
pages = {5809--5825},
publisher = {Optica Publishing Group},
title = {Virtual Hall sensor triggered multi-MHz endoscopic OCT imaging for stable real-time visualization},
volume = {32},
month = {Feb},
year = {2024},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-32-4-5809},
doi = {10.1364/OE.514636},
abstract = {Circumferential scanning in endoscopic imaging is crucial across various disciplines, and optical coherence tomography (OCT) is often the preferred choice due to its high-speed, high-resolution, and micron-scale imaging capabilities. Moreover, real-time and high-speed 3D endoscopy is a pivotal technology for medical screening and precise surgical guidance, among other applications. However, challenges such as image jitter and non-uniform rotational distortion (NURD) are persistent obstacles that hinder real-time visualization during high-speed OCT procedures. To address this issue, we developed an innovative, low-cost endoscope that employs a brushless DC motor for scanning, and a sensorless technique for triggering and synchronizing OCT imaging with the scanning motor. This sensorless approach uses the motor\&\#x2019;s electrical feedback (back electromotive force, BEMF) as a virtual Hall sensor to initiate OCT image acquisition and synchronize it with a Fourier Domain Mode-Locked (FDML)-based Megahertz OCT system. Notably, the implementation of BEMF-triggered OCT has led to a substantial reduction in image jitter and NURD (\<4 mrad), thereby opening up a new window for real-time visualization capabilities. This approach suggests potential benefits across various applications, aiming to provide a more accurate, deployable, and cost-effective solution. Subsequent studies can explore the adaptability of this system to specific clinical scenarios and its performance under practical endoscopic conditions.},
}

@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{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{10.1117/12.2652616,
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{10.1117/12.2652955,
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{10.1117/12.2652847,
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}
}

@article{JACOBI2022S288,
title = {620 Screening an inhibitor library for new drug candidates to promote wound healing},
journal = {Journal of Investigative Dermatology},
volume = {142},
number = {12, Supplement },
pages = {S288},
year = {2022},
note = {ESDR 2022 Meeting Abstract Supplement},
issn = {0022-202X},
doi = {https://doi.org/10.1016/j.jid.2022.09.637},
url = {https://www.sciencedirect.com/science/article/pii/S0022202X22025714},
author = {C. Jacobi and M. Göb and R. Huber and R.J. Ludwig and J.E. Hundt}
}

@inproceedings{10.1117/12.2612171,
author = {Madita G{\"o}b and Sazgar Burhan and Simon Lotz and Robert Huber},
title = {{Towards ultra-large area vascular contrast skin imaging using multi-MHz-OCT}},
volume = {11948},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVI},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1194807},
abstract = {We demonstrate ultra-large field of view OCT scanning using standard optics, a X-Y-galvanometer scanner and a synchronously driven motorized XYZ-positioning stage. The integration of a movable stage into our self-built 3.3 MHz- OCT system allows acquiring coherent ultra-large area images, fully leveraging the high speed potential of our system. For fast OCT-angiography, one galvanometer axis scanner is driven in a repetitive sawtooth pattern, fully synchronized to the movement of the linear stage, to obtain multiple measurements at each position. This technique requires exact synchronization, precise repositioning, and uniform movements with low tolerances to ensure a minimum revisitation error. We analyze error and performance of our setup and demonstrate angiographic imaging.},
keywords = {Optical Coherence Tomography, Fourier Domain Mode Locking, FDML, Optical Coherence Angiography, OCTA, Medical optics and biotechnology, Medical imaging, Three-dimensional image acquisition, Scanners, Microscopy},
year = {2022},
doi = {10.1117/12.2612171},
URL = {https://doi.org/10.1117/12.2612171}
}

@article{Gob:22,
author = {Madita G\"{o}b and Tom Pfeiffer and Wolfgang Draxinger and Simon Lotz and Jan Philip Kolb and Robert Huber},
journal = {Biomed. Opt. Express},
keywords = {High speed imaging; Image processing; Image quality; In vivo imaging; Range imaging; Vertical cavity surface emitting lasers},
number = {2},
pages = {713--727},
publisher = {Optica Publishing Group},
title = {Continuous spectral zooming for in vivo live 4D-OCT with MHz A-scan rates and long coherence},
volume = {13},
month = {Feb},
year = {2022},
url = {https://opg.optica.org/boe/abstract.cfm?URI=boe-13-2-713},
doi = {10.1364/BOE.448353},
abstract = {We present continuous three-dimensional spectral zooming in live 4D-OCT using a home-built FDML based OCT system with 3.28 MHz A-scan rate. Improved coherence characteristics of the FDML laser allow for imaging ranges up to 10 cm. For the axial spectral zoom feature, we switch between high resolution and long imaging range by adjusting the sweep range of our laser. We present a new imaging setup allowing for synchronized adjustments of the imaging range and lateral field of view during live OCT imaging. For this, a novel inline recalibration algorithm was implemented that enables numerical k-linearization of the raw OCT fringes for every frame instead of every volume. This is realized by acquiring recalibration data within the dead time of the raster scan at the turning points of the fast axis scanner. We demonstrate in vivo OCT images of fingers and hands at different resolution modes and show real three-dimensional zooming during live 4D-OCT. A three-dimensional spectral zooming feature for live 4D-OCT is expected to be a useful tool for a wide range of biomedical, scientific and research applications, especially in OCT guided surgery.},
}