1. Johannes F. de Boer

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    1. Mentioned In 108 Articles

    2. Subretinal Fibrosis Detection Using Polarization Sensitive Optical Coherence Tomography

      Subretinal Fibrosis Detection Using Polarization Sensitive Optical Coherence Tomography
      Purpose : Subretinal fibrosis (SRFib) is an important cause of permanent loss-of-vision diseases with submacular neovascularization, but a reliable diagnostic method is currently missing. This study uses polarization-sensitive optical coherence tomography (PS-OCT) to detect SRFib within retinal lesions by measurement of its birefringent collagen fibers. Methods : Twenty-five patients were enrolled with retinal pathology in one or both eyes containing (1) suspected SRFib, (2) lesions suspected not to be fibrotic, or (3 ...
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    3. Toward clinical elastography of dermal tissues: A medical device to probe skin’s elasticity through suction, with subsurface imaging via optical coherence tomography

      Toward clinical elastography of dermal tissues: A medical device to probe skin’s elasticity through suction, with subsurface imaging via optical coherence tomography
      ABSTRACT The mechanical behavior of dermal tissues is unarguably recognized for its diagnostic ability and in the last decades received a steadily increasing interest in dermatology practices. Among the various methods to investigate the mechanics of skin in clinical environments, suction-based ones are especially noteworthy, thanks to their qualities of minimal invasiveness and relative simplicity of setups and data analysis. In such experiments, structural visualization of the sample is highly ...
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    4. Detailed optical coherence tomography angiographic short‐term response of type 3 neovascularization to combined treatment with photodynamic therapy and intravitreal bevacizumab

      Detailed optical coherence tomography angiographic short‐term response of type 3 neovascularization to combined treatment with photodynamic therapy and intravitreal bevacizumab
      Purpose To explore the short‐term vascular and structural changes of type 3 neovascularization using optical coherence tomography angiography (OCT‐A) when treated with a combination of photodynamic therapy (PDT) and intravitreal bevacizumab (IVB), and to evaluate the course of different sequences of the combined therapies. Methods Thirty eyes of 29 treatment‐nave patients with a type 3 neovascularization were included in this prospective observational cohort study. They were all ...
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    5. Artifact Rates for 2D Retinal Nerve Fiber Layer Thickness Versus 3D Retinal Nerve Fiber Layer Volume

      Artifact Rates for 2D Retinal Nerve Fiber Layer Thickness Versus 3D Retinal Nerve Fiber Layer Volume
      Purpose : To compare artifact rates in two-dimensional (2D) versus three-dimensional (3D) retinal nerve fiber layer (RNFL) scans using Spectralis optical coherence tomography (OCT) Methods : Thirteen artifact types in 2D and 3D RNFL scans were identified in 106 glaucomatous eyes and 95 normal eyes. Artifact rates were calculated per B-scan and per eye. In 3D volume scans, artifacts were counted only for the 97 B-scans used to calculate RNFL parameters for ...
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    6. Analysis of Neuroretinal Rim by Age, Race, and Sex Using High-Density 3-Dimensional Spectral-Domain Optical Coherence Tomography

      Analysis of Neuroretinal Rim by Age, Race, and Sex Using High-Density 3-Dimensional Spectral-Domain Optical Coherence Tomography
      rcis: Neuroretinal rim minimum distance band (MDB) thickness is significantly lower in older subjects and African Americans compared with whites. It is similar in both sexes. Purpose: To evaluate the relationship between age, race, and sex with the neuroretinal rim using high-density spectral-domain optical coherence tomography optic nerve volume scans of normal eyes. Methods: A total of 256 normal subjects underwent Spectralis spectral-domain optical coherence tomography optic nerve head volume ...
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    7. Optical coherence tomography velocimetry based on decorrelation estimation of phasor pair ratios (DEPPAIR)

      Optical coherence tomography velocimetry based on decorrelation estimation of phasor pair ratios (DEPPAIR)
      Quantitative velocity estimations in optical coherence tomography requires the estimation of the axial and lateral flow components. Optical coherence tomography measures the depth resolved complex field reflected from a sample. While the axial velocity component can be determined from the Doppler shift or phase shift between a pair of consecutive measurements at the same location, the estimation of the lateral component for in vivo applications is still challenging. One approach ...
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    8. 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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    9. 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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    10. 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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    11. 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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    12. 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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    13. 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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    14. 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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    15. 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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    16. 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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  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.