1. Johannes F. de Boer

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    1. Mentioned In 102 Articles

    2. Optical coherence tomography (OCT) to image active and inactive retinoblastomas as well as retinomas

      Optical coherence tomography (OCT) to image active and inactive retinoblastomas as well as retinomas
      Purpose To illustrate Optical Coherence Tomography (OCT) images of active and inactive retinoblastoma (Rb) tumours. Methods Current observational study included patients diagnosed with retinoblastoma and retinoma who were presented at Amsterdam UMC and Jules‐Gonin Eye Hospital, between November 2010 and October 2017. Patients aged between 0 and 4 years were imaged under general anaesthesia with handheld OCT in supine position. Patients older than 4 years were imaged with the ...
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    3. Optic axis uniformity as a metric to improve the contrast of birefringent structures and analyze the retinal nerve fiber layer in polarization-sensitive optical coherence tomography

      Optic axis uniformity as a metric to improve the contrast of birefringent structures and analyze the retinal nerve fiber layer in polarization-sensitive optical coherence tomography
      A new metric is used to improve the contrast of birefringent structures in biological tissue using polarization-sensitive optical coherence tomography. This metric, optic axis uniformity (OAxU), is based on the optic axis of birefringence and quantifies the uniformity of the optic axis direction. OAxU provides surprisingly strong contrast for fibrous structures such as muscle and the retinal nerve fiber layer (RNFL). We used OAxU for automatic segmentation of the RNFL ...
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    4. PhD Position on Biomedical Optics, Vrije University Amsterdam

      PhD Position on Biomedical Optics, Vrije University Amsterdam
      JOB DESCRIPTION Due to ageing, the impact of vision threatening diseases such as diabetic retinopathy (DR) and age-related macular degeneration ( AMD ) on the health care system will only increase. In this project we will develop techniques to quantitatively assess the oxygen saturation status of the retinal microvasculature. Reduced blood oxygen levels may lead to hypoxia, which is one of the key drivers of the formation of new blood vessels. These ...
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    5. Three-Dimensional Optical Coherence Tomography Imaging for Glaucoma Associated with Boston Keratoprosthesis Type I and II

      Three-Dimensional Optical Coherence Tomography Imaging for Glaucoma Associated with Boston Keratoprosthesis Type I and II
      Precis: 3D spectral domain OCT volume scans of the optic nerve head and the peripapillary area are useful in the management of glaucoma in patients with a type I or II Boston Keratoprosthesis (KPro). Purpose: To report the use of spectral domain optical coherence tomography (OCT) in the management of glaucoma in patients with a type I or II Boston Keratoprosthesis (KPro). Methods: Observational case series. Four consecutive patients with ...
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    6. Diagnostic Capability of 3D Peripapillary Retinal Volume for Glaucoma Using Optical Coherence Tomography Customized Software

      Diagnostic Capability of 3D Peripapillary Retinal Volume for Glaucoma Using Optical Coherence Tomography Customized Software
      Prcis: The diagnostic capability of peripapillary retinal volume is similar to peripapillary retinal nerve fiber layer thickness for diagnosing glaucoma, but with fewer artifacts. Purpose: To compare the diagnostic capability of three-dimensional (3D) peripapillary retinal volume (RV) versus two-dimensional (2D) peripapillary retinal nerve fiber layer (RNFL) thickness for open-angle glaucoma . Patients and Methods: A retrospective cross-sectional analysis was conducted. A total of 180 subjects [113 open-angle glaucomas (OAG), 67 normal ...
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    7. In vivo multifunctional optical coherence tomography at the periphery of the lungs

      In vivo multifunctional optical coherence tomography at the periphery of the lungs
      Remodeling of tissue, such as airway smooth muscle (ASM) and extracellular matrix, is considered a key feature of airways disease. No clinically accepted diagnostic method is currently available to assess airway remodeling or the effect of treatment modalities such as bronchial thermoplasty in asthma, other than invasive airway biopsies. Optical coherence tomography (OCT) generates cross-sectional, near-histological images of airway segments and enables identification and quantification of airway wall layers based ...
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    8. 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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    9. 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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    10. 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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    11. 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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    12. 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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    13. 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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    14. 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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    15. 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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    16. 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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  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.