1. Johannes F. de Boer

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    1. Mentioned In 96 Articles

    2. Classification and treatment follow-up of a juxtapapillary retinal hemangioblastoma with optical coherence tomography angiography

      Classification and treatment follow-up of a juxtapapillary retinal hemangioblastoma with optical coherence tomography angiography
      Purpose Only an endophytic growth pattern in juxtapapillary retinal hemangioblastoma (JRH) is an indication for surgical treatment, but classification of growth types is difficult using conventional imaging techniques. This case report describes the use of optical coherence tomography angiography (OCT-A) features for classification and treatment follow-up in a case with JRH. Observations The JRH of this patient was easily detected with two different OCT-A methods in both en-face and cross-sectional ...
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    3. Optical coherence tomography to detect acute esophageal radiation-induced damage in mice: a validation study

      Optical coherence tomography to detect acute esophageal radiation-induced damage in mice: a validation study
      Radiation therapy for patients with non-small-cell lung cancer is hampered by acute radiation-induced toxicity in the esophagus. This study aims to validate that optical coherence tomography (OCT), a minimally invasive imaging technique with high resolution (~10 m), is able to visualize and monitor acute radiation-induced esophageal damage (ARIED) in mice. We compare our findings with histopathology as the gold standard. Irradiated mice receive a single dose of 40 Gy at ...
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    4. Precision analysis and optimization in phase decorrelation OCT velocimetry

      Precision analysis and optimization in phase decorrelation OCT velocimetry
      Quantitative flow velocimetry in Optical Coherence Tomography is used to determine both the axial and lateral flow component at the level of individual voxels. The lateral flow is determined by analyzing the statistical properties of reflected electro-magnetic fields for repeated measurements at (nearly) the same location. The precision or statistical fluctuation of the quantitative velocity estimation depends on the number of repeated measurements and the method to determine quantitative flow ...
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    5. Effects of Age, Race, and Ethnicity on the Optic Nerve and Peripapillary Region Using Spectral-Domain OCT 3D Volume Scans

      Effects of Age, Race, and Ethnicity on the Optic Nerve and Peripapillary Region Using Spectral-Domain OCT 3D Volume Scans
      Purpose : To evaluate the effects of age, race, and ethnicity on the optic nerve and peripapillary retina using spectral-domain optical coherence tomography (SD-OCT) three-dimensional (3D) volume scans in normal subjects. Methods : This is a cross-sectional study performed at a single institution in Boston. All patients received retinal nerve fiber layer (RNFL) scans and an optic nerve 3D volume scan. The SD-OCT software calculated peripapillary RNFL thickness, retinal thickness (RT), and ...
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    6. Diagnostic Capability of Three-Dimensional Macular Parameters for Glaucoma Using Optical Coherence Tomography Volume Scans

      Diagnostic Capability of Three-Dimensional Macular Parameters for Glaucoma Using Optical Coherence Tomography Volume Scans
      Purpose : To compare the diagnostic capability of three-dimensional (3D) macular parameters against traditional two-dimensional (2D) retinal nerve fiber layer (RNFL) thickness using spectral domain optical coherence tomography. To determine if manual correction and interpolation of B-scans improve the ability of 3D macular parameters to diagnose glaucoma. Methods : A total of 101 open angle glaucoma patients (29 with early glaucoma) and 57 healthy subjects had peripapillary 2D RNFL thickness and 3D ...
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    7. Feasibility of using optical coherence tomography to detect radiation-induced fibrosis and residual cancer extent after neoadjuvant chemo-radiation therapy: an ex vivo study

      Feasibility of using optical coherence tomography to detect radiation-induced fibrosis and residual cancer extent after neoadjuvant chemo-radiation therapy: an ex vivo study
      Treatment of resectable esophageal cancer includes neoadjuvant chemo-radiation therapy (nCRT) followed by esophagectomy in operable patients. High-risk surgery may have been avoided in patients with a pathological complete response (pCR). We investigated the feasibility of optical coherence tomography (OCT) to detect residual cancer and radiation-induced fibrosis in 10 esophageal cancer patients that underwent nCRT followed by esophagectomy. We compared our OCT findings with histopathology. Overall, OCT was able to differentiate ...
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    8. Feasibility of using optical coherence tomography to detect acute radiation-induced esophageal damage in small animal models

      Feasibility of using optical coherence tomography to detect acute radiation-induced esophageal damage in small animal models
      Lung cancer survival is poor, and radiation therapy patients often suffer serious treatment side effects. The esophagus is particularly sensitive leading to acute radiation-induced esophageal damage (ARIED). We investigated the feasibility of optical coherence tomography (OCT) for minimally invasive imaging of the esophagus with high resolution (10m) to detect ARIED in mice. Thirty mice underwent cone-beam computed tomography imaging for initial setup assessment and dose planning followed by a single-dose ...
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    9. In vivo polarization-sensitive optical coherence tomography of human burn scars: birefringence quantification and correspondence with histologically determined collagen density

      In vivo polarization-sensitive optical coherence tomography of human burn scars: birefringence quantification and correspondence with histologically determined collagen density
      Obtaining adequate information on scar characteristics is important for monitoring their evolution and the effectiveness of clinical treatment. The aberrant type of collagen in scars may give rise to specific birefringent properties, which can be determined using polarization-sensitive optical coherence tomography (PS-OCT). The aim of this pilot study was to evaluate a method to quantify the birefringence of the scanned volume and correlate it with the collagen density as measured ...
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    10. Visibility of Fiducial Markers used for Image-Guided Radiation Therapy on Optical Coherence Tomography for Registration with CT: an Esophageal Phantom Study

      Visibility of Fiducial Markers used for Image-Guided Radiation Therapy on Optical Coherence Tomography for Registration with CT: an Esophageal Phantom Study
      Purpose Optical coherence tomography (OCT) is of interest to visualize microscopic esophageal tumor extensions to improve tumor delineation for radiation therapy (RT) planning. Fiducial marker placement is a common method to ensure target localization during planning and treatment. Visualization of these fiducial markers on OCT permits integrating OCT and computed tomography (CT) images used for RT planning via image registration. We studied the visibility of 13 (8 types) commercially available ...
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    11. Diagnostic Capability of Peripapillary 3D Retinal Nerve Fiber Layer Volume for Glaucoma Using Optical Coherence Tomography Volume Scans

      Diagnostic Capability of Peripapillary 3D Retinal Nerve Fiber Layer Volume for Glaucoma Using Optical Coherence Tomography Volume Scans
      Purpose To determine the diagnostic capability of peripapillary 3-dimensional (3D) retinal nerve fiber layer (RNFL) volume measurements from spectral domain optical coherence tomography (OCT) volume scans for open angle glaucoma (OAG). Design Assessment of diagnostic accuracy. Methods Setting: Academic clinical setting. Study population : 180 patients (113 OAG and 67 normal subjects). Observation procedures : One eye per subject was included. Peripapillary 3D RNFL volumes were calculated for global, quadrant, and sector ...
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    12. Twenty-five years of optical coherence tomography: the paradigm shift in sensitivity and speed provided by Fourier domain OCT

      Twenty-five years of optical coherence tomography: the paradigm shift in sensitivity and speed provided by Fourier domain OCT
      Optical coherence tomography (OCT) has become one of the most successful optical technologies implemented in medicine and clinical practice mostly due to the possibility of non-invasive and non-contact imaging by detecting back-scattered light. OCT has gone through a tremendous development over the past 25 years. From its initial inception in 1991 [Science 254 , 1178 (1991)] it has become an indispensable medical imaging technology in ophthalmology. Also in fields like cardiology ...
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    13. Introduction to the feature issue on the 25 year anniversary of optical coherence tomography

      Introduction to the feature issue on the 25 year anniversary of optical coherence tomography
      This feature issue commemorates the approximately 25 year history of Optical Coherence Tomography (OCT), one of the most successful biophotonic technologies. While OCT has technological origins traceable to ultrafast laser development and fiber optic system test instrumentation of the 1980s, innovations in low coherence interferometry for optical ranging and imaging for biomedical applications in the U.S., Europe and Japan by the early 1990s led to coinage of the now ...
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    14. Automatic estimation of retinal nerve fiber bundle orientation in SD-OCT images using a structure-oriented smoothing filter

      Automatic estimation of retinal nerve fiber bundle orientation in SD-OCT images using a structure-oriented smoothing filter
      Optical coherence tomography (OCT) yields high-resolution, three-dimensional images of the retina. A better understanding of retinal nerve fiber bundle (RNFB) trajectories in combination with visual field data may be used for future diagnosis and monitoring of glaucoma. However, manual tracing of these bundles is a tedious task. In this work, we present an automatic technique to estimate the orientation of RNFBs from volumetric OCT scans. Our method consists of several ...
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    15. 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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    16. 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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  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.