Raphael André

Master-Student


Uni- München


Thomas Klein, Raphael André, Wolfgang Wieser, Tom Pfeiffer, and Robert Huber,
Joint aperture detection for speckle reduction and increased collection efficiency in ophthalmic MHz OCT, Biomed. Opt. Express , vol. 4, no. 4, pp. 619-634, 04 2013. Optica Publishing Group.
DOI:10.1364/BOE.4.000619
Bibtex: BibTeX
@article{Klein:13,
author = {Thomas Klein and Raphael Andr\'{e} and Wolfgang Wieser and Tom Pfeiffer and Robert Huber},
journal = {Biomed. Opt. Express},
keywords = {Speckle; Medical optics instrumentation; Medical and biological imaging; Optical coherence tomography; Functional imaging; High speed imaging; Image quality; Imaging techniques; Medical imaging; Ophthalmic imaging},
number = {4},
pages = {619--634},
publisher = {Optica Publishing Group},
title = {Joint aperture detection for speckle reduction and increased collection efficiency in ophthalmic MHz OCT},
volume = {4},
month = {Apr},
year = {2013},
url = {https://opg.optica.org/boe/abstract.cfm?URI=boe-4-4-619},
doi = {10.1364/BOE.4.000619},
abstract = {Joint-aperture optical coherence tomography (JA-OCT) is an angle-resolved OCT method, in which illumination from an active channel is simultaneously probed by several passive channels. JA-OCT increases the collection efficiency and effective sensitivity of the OCT system without increasing the power on the sample. Additionally, JA-OCT provides angular scattering information about the sample in a single acquisition, so the OCT imaging speed is not reduced. Thus, JA-OCT is especially suitable for ultra high speed in-vivo imaging. JA-OCT is compared to other angle-resolved techniques, and the relation between joint aperture imaging, adaptive optics, coherent and incoherent compounding is discussed. We present angle-resolved imaging of the human retina at an axial scan rate of 1.68 MHz, and demonstrate the benefits of JA-OCT: Speckle reduction, signal increase and suppression of specular and parasitic reflections. Moreover, in the future JA-OCT may allow for the reconstruction of the full Doppler vector and tissue discrimination by analysis of the angular scattering dependence.},
}
Cedric Blatter, Branislav Grajciar, Tilman Schmoll, Rainer A. Leitgeb, Thomas Klein, Wolfgang Wieser, Raphael André, and Robert Huber,
Ultrahigh-speed non-invasive widefield angiography, Journal of Biomedical Optics , vol. 17, no. 7, pp. 070505, 06 2012. SPIE.
DOI:10.1117/1.JBO.17.7.070505
Bibtex: BibTeX
@article{10.1117/1.JBO.17.7.070505,
author = {Cedric Blatter and Branislav Grajciar and Tilman Schmoll and Rainer A. Leitgeb and Thomas Klein and Wolfgang Wieser and Raphael J. Andr{\'e} and Robert Huber},
title = {{Ultrahigh-speed non-invasive widefield angiography}},
volume = {17},
journal = {Journal of Biomedical Optics},
number = {7},
publisher = {SPIE},
pages = {070505},
abstract = {Retinal and choroidal vascular imaging is an important diagnostic benefit for ocular diseases such as age-related macular degeneration. The current gold standard for vessel visualization is fluorescence angiography. We present a potential non-invasive alternative to image blood vessels based on functional Fourier domain optical coherence tomography (OCT). For OCT to compete with the field of view and resolution of angiography while maintaining motion artifacts to a minimum, ultrahigh-speed imaging has to be introduced. We employ Fourier domain mode locking swept source technology that offers high quality imaging at an A-scan rate of up to 1.68 MHz. We present retinal angiogram over ∼ 48  deg acquired in a few seconds in a single recording without the need of image stitching. OCT at 1060 nm allows for high penetration in the choroid and efficient separate characterization of the retinal and choroidal vascularization.},
keywords = {Angiography, Optical coherence tomography, Image segmentation, Retina, Capillaries, Tissues, Visualization, Diagnostics, Gold, Vascular imaging},
year = {2012},
doi = {10.1117/1.JBO.17.7.070505},
URL = {https://doi.org/10.1117/1.JBO.17.7.070505}
}
Thomas Klein, Wolfgang Wieser, Raphael André, Tom Pfeiffer, Christoph M. Eigenwillig, and Robert Huber,
Multi-MHz FDML OCT: snapshot retinal imaging at 6.7 million axial-scans per second, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XVI , Joseph A. Izatt and James G. Fujimoto and Valery V. Tuchin, Eds. SPIE, 022012. pp. 82131E.
DOI:10.1117/12.908798
Bibtex: BibTeX
@inproceedings{10.1117/12.908798,
author = {Thomas Klein and Wolfgang Wieser and Raphael Andr{\'e} and Tom Pfeiffer and Christoph M. Eigenwillig and Robert Huber},
title = {{Multi-MHz FDML OCT: snapshot retinal imaging at 6.7 million axial-scans per second}},
volume = {8213},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XVI},
editor = {Joseph A. Izatt and James G. Fujimoto and Valery V. Tuchin},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {82131E},
abstract = {We demonstrate the acquisition of densely sampled wide-field 3D OCT datasets of the human retina in 0.3s. This
performance is achieved with a multi-MHz Fourier domain mode-locked (FDML) laser source operating at 1050nm. A two-beam
setup doubles the 3.35MHz laser sweep rate to 6.7MHz, which is 16x faster than results achieved with any non-FDML
source used for retinal OCT. We discuss two main benefits of these high line rates: First, large datasets over an ultra-wide
field of view can be acquired with a low probability of distortions. Second, even if eye movements occur, now the scan rate
is high enough to directly correct even the fastest saccades without loss of information.},
keywords = {Optical coherence tomography, OCT, MHz OCT, Fourier-domain mode-locking, FDML, retinal imaging},
year = {2012},
doi = {10.1117/12.908798},
URL = {https://doi.org/10.1117/12.908798}
}