1. Johannes F. de Boer

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    1. Mentioned In 83 Articles

    2. Polarization sensitive optical coherence tomography – a review [Invited]

      Polarization sensitive optical coherence tomography – a review [Invited]
      Optical coherence tomography (OCT) is now a well-established modality for high-resolution cross-sectional and three-dimensional imaging of transparent and translucent samples and tissues. Conventional, intensity based OCT, however, does not provide a tissue-specific contrast, causing an ambiguity with image interpretation in several cases. Polarization sensitive (PS) OCT draws advantage from the fact that several materials and tissues can change the lights polarization state, adding an additional contrast channel and providing quantitative ...
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    3. Enhanced Diagnostic Capability for Glaucoma of 3-Dimensional Versus 2-Dimensional Neuroretinal Rim Parameters Using Spectral Domain Optical Coherence Tomography

      Enhanced Diagnostic Capability for Glaucoma of 3-Dimensional Versus 2-Dimensional Neuroretinal Rim Parameters Using Spectral Domain Optical Coherence Tomography
      Purpose: To compare the diagnostic capability of 3-dimensional (3D) neuroretinal rim parameters with existing 2-dimensional (2D) neuroretinal and retinal nerve fiber layer (RNFL) thickness rim parameters using spectral domain optical coherence tomography (SD-OCT) volume scans. Materials and Methods: Design: Institutional prospective pilot study. Study population: 65 subjects (35 open-angle glaucoma patients, 30 normal patients). Observation procedures: One eye of each subject was included. SD-OCT was used to obtain 2D RNFL ...
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    4. Comprehensive Three-Dimensional Analysis of the Neuroretinal Rim in Glaucoma Using High-Density Spectral-Domain Optical Coherence Tomography Volume Scans

      Comprehensive Three-Dimensional Analysis of the Neuroretinal Rim in Glaucoma Using High-Density Spectral-Domain Optical Coherence Tomography Volume Scans
      Purpose : To describe spectral-domain optical coherence tomography (OCT) methods for quantifying neuroretinal rim tissue in glaucoma and to compare these methods to the traditional retinal nerve fiber layer thickness diagnostic parameter. Methods : Neuroretinal rim parameters derived from three-dimensional (3D) volume scans were compared with the two-dimensional (2D) Spectralis retinal nerve fiber layer (RNFL) thickness scans for diagnostic capability. This study analyzed one eye per patient of 104 glaucoma patients and ...
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    5. Diagnostic performance of a novel 3D neuroretinal rim parameter for glaucoma using high-density volume scans

      Diagnostic performance of a novel 3D neuroretinal rim parameter for glaucoma using high-density volume scans
      Purpose To describe optical coherence tomography angiography (OCTA) findings in multifocal choroiditis (MFC) with active lesions and to characterize the concordance between the OCTA and other traditional imaging modalities. Design Reliability and validity analysis. Methods Patients with suspected choroidal neovascularization (CNV) or acute inflammatory lesions associated with MFC were assessed in this study. All participants underwent preliminary traditional multimodal imaging including color fundus photography, fundus autofluorescence, near-infrared reflectance imaging, spectral-domain ...
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    6. Process, arrangements and systems for providing frequency domain imaging of a sample

      Process, arrangements and systems for providing frequency domain imaging of a sample
      Exemplary apparatus, arrangement and method can be provided for obtaining information associated with an anatomical structure or sample using optical microscopy. A radiation can include first electromagnetic radiation(s) directed to an anatomical sample and at least one second electromagnetic radiation directed to a reference. A wavelength of the radiation can vary over time, and the wavelength can be shorter than approximately 1150 nm. An interference can be detected between ...
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    7. Correlation of localized glaucomatous visual field defects and spectral domain optical coherence tomography retinal nerve fiber layer thinning using a modified structure–function map for OCT

      Correlation of localized glaucomatous visual field defects and spectral domain optical coherence tomography retinal nerve fiber layer thinning using a modified structure–function map for OCT
      Purpose To study the correlation between glaucomatous visual field (VF) defects assessed by standard automated perimetry (SAP) and peripapillary retinal nerve fiber layer (RNFL) thinning measured by spectral domain optical coherence tomography (OCT) using a modified OCT-based peripapillary RNFL structurefunction map. Patients and methods Perimetric glaucoma patients and age-matched normal control subjects were recruited from a university hospital clinic. All eyes underwent testing with the Spectralis spectral domain OCT and ...
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    8. Process, system and software arrangement for determining at least one location in a sample using an optical coherence tomography

      Process, system and software arrangement for determining at least one location in a sample using an optical coherence tomography
      A system, process and software arrangement are provided to determine at least one position of at least one portion of a sample. In particular, information associated with the portion of the sample is obtained. Such portion may be associated with an interference signal that includes a first electro-magnetic radiation received from the sample and a second electro-magnetic radiation received from a reference. In addition, depth information and/or lateral information ...
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    9. Loosely coupled level sets for simultaneous 3D retinal layer segmentation in optical coherence tomography

      Loosely coupled level sets for simultaneous 3D retinal layer segmentation in optical coherence tomography
      Optical coherence tomography (OCT) yields high-resolution, three-dimensional images of the retina. Reliable segmentation of the retinal layers is necessary for the extraction of clinically useful information. We present a novel segmentation method that operates on attenuation coefficients and incorporates anatomical knowledge about the retina. The attenuation coefficients are derived from in-vivo human retinal OCT data and represent an optical property of the tissue. Then, the layers in the retina are ...
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    10. Phase-resolved Doppler Optical Coherence Tomographic features in Retinal Angiomatous Proliferation

      Phase-resolved Doppler Optical Coherence Tomographic features in Retinal Angiomatous Proliferation
      Purpose To study patients diagnosed with retinal angiomatous proliferation (RAP) based on conventional imaging techniques with phase-resolved Doppler optical coherence tomography (OCT) to detect and localize blood flow in RAP lesions and to compare these findings to conventional imaging, which are mostly invasive and give limited information concerning intra- and transretinal blood flow. Design Single-center, consecutive observational case series. Methods Twelve treatment-nave patients diagnosed with RAP based on fundus examination ...
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    11. Apparatus, method and system for performing phase-resolved optical frequency domain imaging

      Apparatus, method and system for performing phase-resolved optical frequency domain imaging
      Apparatus, system and method are provided which utilize signals received from a reference and a sample. In particular, a radiation is provided which includes at least one first electro-magnetic radiation directed to the sample and at least one second electro-magnetic radiation directed to the reference. A frequency of the radiation varies over time. An interference can be detected between at least one third radiation associated with the first radiation and ...
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    12. In vivo optical microscopy of peripheral nerve myelination with polarization sensitive-optical coherence tomography

      In vivo optical microscopy of peripheral nerve myelination with polarization sensitive-optical coherence tomography
      Assessing nerve integrity and myelination after injury is necessary to provide insight for treatment strategies aimed at restoring neuromuscular function. Currently, this is largely done with electrical analysis, which lacks direct quantitative information. In vivo optical imaging with sufficient imaging depth and resolution could be used to assess the nerve microarchitecture. In this study, we examine the use of polarization sensitive-optical coherence tomography (PS-OCT) to quantitatively assess the sciatic nerve ...
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    13. Polarization sensitive optical frequency domain imaging system for endobronchial imaging

      Polarization sensitive optical frequency domain imaging system for endobronchial imaging
      A polarization sensitive endoscopic optical frequency domain imaging (PS-OFDI) system with a motorized distal scanning catheter is demonstrated. It employs a passive polarization delay unit to multiplex two orthogonal probing polarization states in depth, and a polarization diverse detection unit to detect interference signal in two orthogonal polarization channels. Per depth location four electro-magnetic field components are measured that can be represented in a complex 2x2 field matrix. A Jones ...
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    14. Correlation of localized glaucomatous visual field defects and spectral domain optical coherence tomography retinal nerve fiber layer thinning using a modified structure-function map for OCT

      Correlation of localized glaucomatous visual field defects and spectral domain optical coherence tomography retinal nerve fiber layer thinning using a modified structure-function map for OCT
      Purpose To study the correlation between glaucomatous visual field (VF) defects assessed by standard automated perimetry (SAP) and peripapillary retinal nerve fiber layer (RNFL) thinning measured by spectral domain optical coherence tomography (OCT) using a modified OCT-based peripapillary RNFL structurefunction map. Patients and methods Perimetric glaucoma patients and age-matched normal control subjects were recruited from a university hospital clinic. All eyes underwent testing with the Spectralis spectral domain OCT and ...
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    15. Direct Blood Flow Measurements in a Free RPE-Choroid Graft with Phase-Resolved Doppler OCT

      Direct Blood Flow Measurements in a Free RPE-Choroid Graft with Phase-Resolved Doppler OCT
      Purpose: We directly demonstrated the revascularization in a free retinal pigment epithelium (RPE)-choroid graft with direct blood flow detection by experimental phase-resolved Doppler optical coherence tomography (PRD-OCT). Methods: Seven patients with age-related macular degeneration underwent an RPE-choroid graft translocation in a prospective institutional cohort study. Spectral domain optical coherence tomography (SD-OCT) was used to measure the revascularization stage. With PRD-OCT the presence of flow was imaged postoperatively. Results: The ...
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    16. Fiber-based polarization-sensitive OCT of the human retina with correction of system polarization distortions

      Fiber-based polarization-sensitive OCT of the human retina with correction of system polarization distortions
      In polarization-sensitive optical coherence tomography (PS-OCT) the use of single-mode fibers causes unpredictable polarization distortions which can result in increased noise levels and erroneous changes in calculated polarization parameters. In the current paper this problem is addressed by a new Jones matrix analysis method that measures and corrects system polarization distortions as a function of wavenumber by spectral analysis of the sample surface polarization state and deeper located birefringent tissue ...
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  2. About Johannes F. de Boer

    Johannes F. de Boer

    Johannes F. de Boer is a professor in the Department of Physics at Vrije Universiteit, Amsterdam The Netherlands.  His research interests: The long-term goal of the research is to develop minimally invasive optical imaging and microscopy technologies for 3-dimensional structural and functional mapping of biological tissues and specimens. A main thrust of my research is in the area of Optical Coherence Tomography (OCT). OCT creates in-vivo cross-sectional images approaching the cellular level in a non-invasive or minimally invasive way. OCT can potentially provide “optical biopsies” for real time in-vivo diagnosis, and since tissue does not need to be excised, allows functional biopsies of living tissue. My group has pioneered Polarization Sensitive OCT (PS-OCT). Over the past years we have played a leading role in the development of Spectral Domain OCT (SD/FD-OCT and OFDI) that is a hundred to a thousand times more sensitive than current state of the art OCT. The increase of light detection efficiency by 2 to 3 orders of magnitude allows In-vivo video rate imaging of biological structures with better signal to noise and enhanced depth resolution. The increase in speed represents a paradigm shift from point sampling to 3-dimensional screening of large tissue volumes. We were the first to demonstrate video rate OCT and ultra-high resolution imaging of the human retina. The superior phase stability of the new technology results in sensitivity enhancements to functional OCT, such as Doppler velocimetry and polarization and phase sensitivity. This allows video rate mapping of functionality such as flow velocity profiles in retinal arteries and characterization of structural properties such as retinal nerve fiber layer birefringence. We are developing comprehensive 3-D retinal mapping of structure, flow velocity and retinal nerve fiber layer birefringence for a better understanding of a variety of diseases in ophthalmology, in particular glaucoma. In addition, the current research projects include human studies in the area of otolaryngology and skin and small animal imaging. A second and rapidly expanding research area is optical coherence phase contrast microscopy. Phase contrast techniques give motion resolution on the order of 1-2 nm, permitting non-contact optical detection of action potentials in nerve tissue. Combined with the depth discrimination of OCT, this provides the ability to isolate phase changes to within the coherence length of the light source, i.e., 2-3 micron. The combination of structural and phase sensitive microscopy with sub-wavelength resolution allows 3-D phase contrast imaging of cell dynamics.