Publications de Rainer Leitgeb

Laser Doppler imaging for intraoperative human brain mapping

Michaël Unser, Dimitri Nestor Alice Van De Ville, Theo Lasser, Marcel Leutenegger, Rainer Leitgeb, Erica Martin-Williams

The identification and accurate location of centers of brain activity are vital both in neuro-surgery and brain research. This study aimed to provide a non-invasive, non-contact, accurate, rapid and user-friendly means of producing functional images intrao ...

Elsevier2009

In vivo imaging of murine endocrine islets of Langerhans with extended-focus optical coherence microscopy

Theo Lasser, Rainer Leitgeb, Anne Grapin-Botton, Martin Villiger, Joan Goulley, Michael Friedrich

Aims/hypothesis Structural and functional imaging of the islets of Langerhans and the insulin-secreting beta cells represents a significant challenge and a long-lasting objective in diabetes research. In vivo microscopy offers a valuable insight into beta ...

Springer Verlag2009

Information Limits of Optical Coherence Imaging Through Scattering Media

Theo Lasser, Rainer Leitgeb

We develop an information-theoretic framework for the quantitative assessment of the maximum amount of information provided by optical coherence imaging through scattering media. We use our approach to investigate the fundamental dependence of the extracta ...

2009

See the Brain at Work—Intraoperative Laser Doppler Functional Brain Imaging

Michaël Unser, Theo Lasser, Marcel Leutenegger, Dimitri Nestor Alice Van De Ville, Rainer Leitgeb, Antonio Lopez, Erica Martin-Williams

During open brain surgery we acquire perfusion images non-invasively using laser Doppler imaging. The regions of brain activity show a distinct signal in response to stimulation providing intraoperative functional brain maps of remarkably strong contrast. ...

2009

Optical apparatus for dual beam heterodyne Fourier domain optical coherence tomography, has detector that synchronizes phase shift such that sample signal or sample interface moving at arbitrary velocity is detected by phase change

Theo Lasser, Rainer Leitgeb, Martin Villiger, Adrian Bachmann, Roland Michaely

NOVELTY - The apparatus has an optical unit for splitting a source field to produce and combine reference and biomedical sample light fields. An optical and electronic unit records a spectral interference pattern between combined light fields. A controlled ...

2008

Frequency encoded assessment of retinal physiology

Theo Lasser, Adrian Bachmann, Rainer Leitgeb, Roland Michaely, Cédric Blatter

We demonstrate in-vivo functional imaging of the human retina with Fourier domain optical coherence tomography employing frequency encoding of an excitation pattern. The principle is based on projecting a modulated rectangular pattern across the foveal reg ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2008

Theoretical analysis of complex-conjugate-ambiguity suppression in frequency-domain optical-coherence tomography

Michaël Unser, Rainer Leitgeb, Roland Michaely

New phase-shifting techniques have recently been proposed to suppress the complex-conjugate ambiguity in frequency-domain optical-coherence tomography. A phase shift is introduced, in an elegant fashion, by incorporating a small beam offset at the scanning ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2008

Exact and Efficient Signal Reconstruction in Frequency-Domain Optical-Coherence Tomography

Michaël Unser, Rainer Leitgeb, Chandra Sekhar Seelamantula

We address the problem of tomogram reconstruction in frequency-domain optical-coherence tomography. We propose a new technique for suppressing the autocorrelation artifacts that are commonly encountered with the conventional Fourier-transform-based approac ...

OSA2008

Vectorial retinal blood flow and optical vessel vivisection for 3D angiography with high resolution resonant Doppler OCT

Theo Lasser, Martin Villiger, Rainer Leitgeb, Cédric Blatter, Adrian Bachmann, Roland Michaely

PURPOSE: To perform high speed and completely non-invasive 3D angiography at the optic nerve head region and to reconstruct vectorial 3D blood flow from optically segmented blood vessel structure as a pre-requisite for testing retinal function and physiolo ...

2007

Intensity based quantification of fast retinal blood flow in 3D via high resolution resonant Doppler spectral OCT

Theo Lasser, Cédric Blatter, Rainer Leitgeb, Martin Villiger, Adrian Bachmann, Roland Michaely

Resonant Doppler Fourier Domain Optical Coherence Tomography is a functional imaging modality for quantifying fast tissue flow. The method profits from the effect of interference fringe blurring in spectrometer-based FDOCT in the presence of sample motion. ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2007