1. Dirk J. Faber

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    1. Mentioned In 55 Articles

    2. OCT Amplitude and Speckle Statistics of Discrete Random Media

      OCT Amplitude and Speckle Statistics of Discrete Random Media
      Speckle, amplitude fluctuations in optical coherence tomography (OCT) images, contains information on sub-resolution structural properties of the imaged sample. Speckle statistics could therefore be utilized in the characterization of biological tissues. However, a rigorous theoretical framework relating OCT speckle statistics to structural tissue properties has yet to be developed. As a first step, we present a theoretical description of OCT speckle, relating the OCT amplitude variance to size and organization ...
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    3. 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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    4. Applicability of quantitative optical imaging techniques for intraoperative perfusion diagnostics: a comparison of laser speckle contrast imaging, sidestream dark-field microscopy, and optical coherence tomography

      Applicability of quantitative optical imaging techniques for intraoperative perfusion diagnostics: a comparison of laser speckle contrast imaging, sidestream dark-field microscopy, and optical coherence tomography
      . Patient morbidity and mortality due to hemodynamic complications are a major problem in surgery. Optical techniques can image blood flow in real-time and high-resolution, thereby enabling perfusion monitoring intraoperatively. We tested the feasibility and validity of laser speckle contrast imaging (LSCI), optical coherence tomography (OCT), and sidestream dark-field microscopy (SDF) for perfusion diagnostics in a phantom model using whole blood. Microvessels with diameters of 50, 100, and 400 m were ...
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    5. Optical Coherence Tomography as a Tool for in Vivo Staging and Grading of Upper Urinary Tract Urothelial Carcinoma: A Study for Diagnostic Accuracy

      Optical Coherence Tomography as a Tool for in Vivo Staging and Grading of Upper Urinary Tract Urothelial Carcinoma: A Study for Diagnostic Accuracy
      Purposes Biopsies and cytology are cornerstones in the diagnosis of upper urinary tract urothelial carcinoma (UTUC). However, a high rate of non-diagnostic biopsies, tumor upgrading and -staging after nephroureterectomy is observed. In this prospective in vivo study we aimed to evaluate the diagnostic accuracy of OCT for grading and staging of UTUC Material Methods Twenty-six patients underwent diagnostic URS including biopsies and OCT imaging, followed by nephroureterectomy or segmental ureter ...
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    6. Prostate cancer diagnosis by optical coherence tomography: First results from a needle based optical platform for tissue sampling

      Prostate cancer diagnosis by optical coherence tomography: First results from a needle based optical platform for tissue sampling
      The diagnostic accuracy of Optical Coherence Tomography (OCT) based optical attenuation coefficient analysis is assessed for the detection of prostate cancer. Needle-based OCT-measurements were performed on the prostate specimens. Attenuation coefficients were determined by an earlier described in-house developed software package. The mean attenuation coefficients (benign OCT data; malignant OCT data; p-value Mann-Whitney U test) were: (3.56 mm 1 ; 3.85 mm 1 ; p 0.0001) for all patients ...
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    7. Customized Tool for the Validation of Optical Coherence Tomography in Differentiation of Prostate Cancer

      Customized Tool for the Validation of Optical Coherence Tomography in Differentiation of Prostate Cancer
      Objective: To design and demonstrate a customized tool to generate histologic sections of the prostate that directly correlate with needle-based optical coherence tomography pullback measurements. Materials and Methods: A customized tool was created to hold the prostatectomy specimens during optical coherence tomography measurements and formalin fixation. Using the tool, the prostate could be sliced into slices of 4 mm thickness through the optical coherence tomography measurement trajectory. In this way ...
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    8. Validation of quantitative attenuation and backscattering coefficient measurements by optical coherence tomography in the concentration-dependent and multiple scattering regime

      Validation of quantitative attenuation and backscattering coefficient measurements by optical coherence tomography in the concentration-dependent and multiple scattering regime
      Optical coherence tomography (OCT) has the potential to quantitatively measure optical properties of tissue such as the attenuation coefficient and backscattering coefficient. However, to obtain reliable values for strong scattering tissues, accurate consideration of the effects of multiple scattering and the nonlinear relation between the scattering coefficient and scatterer concentration (concentration-dependent scattering) is required. We present a comprehensive model for the OCT signal in which we quantitatively account for both ...
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    9. Percutaneous Needle Based Optical Coherence Tomography for the Differentiation of Renal Masses: a Pilot Cohort

      Percutaneous Needle Based Optical Coherence Tomography for the Differentiation of Renal Masses: a Pilot Cohort
      To view the full text, please login as a subscribed user or purchase a subscription . Click here to view the full text on ScienceDirect. The aim of this study is to determine the ability of percutaneous needle based Optical Coherence Tomography (OCT) to differentiate renal masses, by using the attenuation coefficient (OCT, mm-1) as a quantitative measure. Percutaneous needle based OCT of the kidney was performed in patients presenting with ...
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    10. Learning curve and interobserver variance in quantification of the optical coherence tomography attenuation coefficient

      Learning curve and interobserver variance in quantification of the optical coherence tomography attenuation coefficient
      The learning curve and interobserver variance of attenuation coefficient ( OCT ) determination from optical coherence tomography (OCT) images were quantified. The OCT of normal and diseased vulvar tissues was determined at five time points by three novice students and three OCT experts who reached consensus for reference. Students received feedback between time points. Eventually, variance in OCT was smaller in images of diseased tissue than in images of normal vulvar tissue ...
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    11. Assesment of apoptosis induced changes in scattering using optical coherence tomography

      Assesment of apoptosis induced changes in scattering using optical coherence tomography
      The aim of this study is to identify changes in scattering with optical coherence tomography (OCT) and relate these measurements with mitochondrial changes during the initiation of apoptosis. Human retinal pigment epithelial cells were cultured and apoptosis was induced using 10% alcohol. Using the attenuation coefficient and backscattering, changes were measured during cell death in a cell-pellet and monolayer respectively. To confirm apoptosis, fluorescent activated cell sorting was used. Mitochondrial ...
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    12. Optical coherence tomography accurately identifies patients with penile (pre) malignant lesions: A single center prospective study

      Optical coherence tomography accurately identifies patients with penile (pre) malignant lesions: A single center prospective study
      Introduction: Currently, (multiple) biopsies are taken to obtain histopathological diagnosis of suspicious lesions of the penile skin. Optical coherence tomography (OCT) provides noninvasive in vivo images from which epidermal layer thickness and attenuation coefficient (m oct ) can be quantified. We hypothesize that qualitative (image assessment) and quantitative (epidermal layer thickness and attenuation coefficient, m oct ) analysis of penile skin with OCT is possible and may differentiate benign penile tissue from ...
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    13. Prostate cancer diagnosis: the feasibility of needle-based optical coherence tomography

      Prostate cancer diagnosis: the feasibility of needle-based optical coherence tomography
      The objective of this study is to demonstrate the feasibility of needle-based optical coherence tomography (OCT) and functional analysis of OCT data along the full pullback trajectory of the OCT measurement in the prostate, correlated with pathology. OCT images were recorded using a commercially available C7-XR OCT Intravascular Imaging System interfaced to a C7 Dragonfly intravascular 0.9-mm-diameter imaging probe. A computer program was constructed for automated image attenuation analysis ...
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    14. Detection of buried Barrett’s glands after radiofrequency ablation with volumetric laser endomicroscopy

      Detection of buried Barrett’s glands after radiofrequency ablation with volumetric laser endomicroscopy
      Background and Aims The prevalence and clinical relevance of buried Barretts glands (BB) after radiofrequency ablation (RFA) in Barretts esophagus (BE) are debated. Recent optical coherence tomography studies demonstrated a high prevalence of BBs. Direct histological correlation, however, has been lacking. Volumetric laser endomicroscopy (VLE) is a second-generation optical coherence tomography system capable of scanning a large surface of the esophageal wall layers with low-power microscopy resolution. The aim was ...
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    15. Volumetric laser endomicroscopy in Barrett's esophagus: a feasibility study on histological correlation

      Volumetric laser endomicroscopy in Barrett's esophagus: a feasibility study on histological correlation
      Volumetric laser endomicroscopy (VLE) is a novel balloon-based optical coherence tomography (OCT) imaging technique that may improve detection of early neoplasia in Barrett's esophagus (BE). Most OCT studies lack a direct correlation between histology and OCT images. The aim is to investigate the optimal approach for achieving one-to-one correlation of ex-vivo VLE images of endoscopic resection (ER) specimens with histology. BE patients with and without early neoplasia underwent ER ...
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    16. In Vivo, Percutaneous, Needle Based, Optical Coherence Tomography of Renal Masses

      In Vivo, Percutaneous, Needle Based, Optical Coherence Tomography of Renal Masses
      Optical coherence tomography (OCT) is the optical equivalent of ultrasound imaging, based on the backscattering of near infrared light. OCT provides real time images with a 15 m axial resolution at an effective tissue penetration of 2-3 mm. Within the OCT images the loss of signal intensity per millimeter of tissue penetration, the attenuation coefficient, is calculated. The attenuation coefficient is a tissue specific property, providing a quantitative parameter for ...
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  2. About Dirk J. Faber

    Dirk J. Faber

    Dirk J. Faber is with the Department of Biomedical Engineering and Physics at the Academic Medical Center at the University of Amsterdam.

  3. Quotes

    1. It has to have some size. If you could use OCT to look at the molecular level then you could image cells directly.
      In Biomedical Optics & Medical Imaging: Tiny treatments promise big results
    2. The advantages of nanoparticles are that you can bind them to anything you want to and they can be designed to have really good contrast. You can't do this with fluorophores, for example. They just fluoresce at certain wavelengths.
      In Tiny treatments promise big results