1. Articles from Peter M. Andrews

    1-12 of 12
    1. Optical coherence tomography and computer-aided diagnosis of a murine model of chronic kidney disease

      Optical coherence tomography and computer-aided diagnosis of a murine model of chronic kidney disease

      Chronic kidney disease (CKD) is characterized by a progressive loss of renal function over time. Histopathological analysis of the condition of glomeruli and the proximal convolutional tubules over time can provide valuable insights into the progression of CKD. Optical coherence tomography (OCT) is a technology that can analyze the microscopic structures of a kidney in a nondestructive manner. Recently, we have shown that OCT can provide real-time imaging of kidney microstructures in vivo without administering exogenous contrast agents. A murine model of CKD induced by intravenous Adriamycin (ADR) injection is evaluated by OCT. OCT images of the rat kidneys have ...

      Read Full Article
    2. Monitoring Kidney Microanatomy Changes During Ischemia-Reperfusion Process Using Texture Analysis of OCT Images

      Monitoring Kidney Microanatomy Changes During Ischemia-Reperfusion Process Using Texture Analysis of OCT Images

      Impact Statement: Tubular diameter has been developed previously as a potential biomarker for the transplant kidney. However, the tubular lumens were segmented out based on an empirically-determined threshold. In our study, a fully automatic texture analysis algorithm has been developed for OCT image analysis of kidney microanatomy during ischemia-reperfusion process. Our method can potentially be applicable in evaluating the status of donor kidneys prior to and after their transplantation. Abstract: Kidney ischemia-reperfusion (I/R) accounts for the majority of acute kidney injury cases, whose consequences are commonly encountered after kidney transplantation. Optical coherence tomography (OCT) has been applied to image ...

      Read Full Article
    3. Optical Coherence Tomography of the Aging Kidney

      Optical Coherence Tomography of the Aging Kidney

      Objectives: The aging kidney exhibits a progressive decline in renal function with characteristic histopathologic changes and is a risk factor for renal transplant. However, the degree to which the kidney exhibits this decline depends on several factors that vary from one individual to the next. Optical coherence tomography is an evolving noninvasive imaging technology that has recently been used to evaluate acute tubular necrosis of living-human donor kidneys before their transplant. With the increasing use of kidneys from older individuals, it is important to determine whether optical coherence tomography also can distinguish the histopathology associated with aging. Materials and Methods ...

      Read Full Article
    4. Optical coherence tomography (OCT) of a murine model of chronic kidney disease

      Optical coherence tomography (OCT) of a murine model of chronic kidney disease

      Chronic Kidney Disease (CKD) is characterized by a progressive loss in renal function over time. Pathology can provide valuable insights into the progression of CKD by analyzing the status of glomeruli and the uriniferous tubules over time. Optical coherence tomography (OCT) is a new procedure that can analyze the microscopic structure of the kidney in a non-invasive manner. This is especially important because there are significant artifacts associated with excision biopsies and immersion fixation procedures. Recently, we have shown that OCT can provide real time images of kidney microstructure and Doppler OCT (DOCT) can image glomerular renal blood flow in ...

      Read Full Article
    5. Mannitol Infusion Within 15 Min of Cross-Clamp Improves Living Donor Kidney Preservation

      Mannitol Infusion Within 15 Min of Cross-Clamp Improves Living Donor Kidney Preservation

      BACKGROUND: Optical coherence tomography (OCT) revealed that cells lining proximal convoluted tubules of living donor kidneys (LDKs) procured by laparoscopic procedures were very swollen in response to the brief period of ischemia experienced between the time of arterial vessel clamping and flushing the excised kidney with cold preservation solution. Damage to the tubules as a result of this cell swelling resulted in varying degrees of acute tubular necrosis (ATN) that slowed the recovery of the donor kidneys during the first 2 weeks after their transplantation. METHODS: To prevent this cell damage during LDK procurement, we changed the protocol for intravenous ...

      Read Full Article
    6. Using Optical Coherence Tomography (OCT) to Evaluate Human Donor Kidneys Prior to and Following Transplantation

      Using Optical Coherence Tomography (OCT) to Evaluate Human Donor Kidneys Prior to and Following Transplantation

      The most common insult to donor kidneys destined for transplantation is Acute Tubular Necrosis (ATN). The extent of ATN will affect post-transplant function and is a significant risk factor for long-term graft function and survival. Optical Coherence Tomography (OCT) is a rapidly emerging imaging modality that can function as a type of “optical biopsy”, providing non-invasive images of tissue morphology in situ and in real-time. In this paper, we review studies that support the use of OCT and Doppler based OCT (i.e., DOCT) to image the renal microstructure and blood flow of human donor kidneys. We conclude that OCT ...

      Read Full Article
    7. Optical Coherence Tomography of the Living Human Kidney

      Optical Coherence Tomography of the Living Human Kidney

      Acute tubular necrosis (ATN) induced by ischemia is the most common insult to donor kidneys destined for transplantation. ATN results from swelling and subsequent damage to cells lining the kidney tubules. In this study, we demonstrate the capability of optical coherence tomography (OCT) to image the renal microstructures of living human donor kidneys and potentially provide a measure to determine the extent of ATN. We also found that Doppler-based OCT (i.e., DOCT) reveals renal blood flow dynamics that is another major factor which could relate to post-transplant renal function. All OCT/DOCT observations were performed in a noninvasive, sterile ...

      Read Full Article
    8. In vivo, label-free, three-dimensional quantitative imaging of kidney microcirculation using Doppler optical coherence tomography

      In vivo, label-free, three-dimensional quantitative imaging of kidney microcirculation using Doppler optical coherence tomography
      Doppler optical coherence tomography (DOCT) is a functional extension of optical coherence tomography (OCT) and is currently being employed in several clinical arenas to quantify blood flow in vivo. In this study, the objective was to investigate the feasibility of DOCT to image kidney microcirculation, specifically, glomerular blood flow. DOCT is able to capture three-dimensional (3D) data sets consisting of a series of cross-sectional images in real time, which enables label-free and non-destructive quantification of glomerular blood flow. The kidneys of adult, male Munich–Wistar rats were exposed through laparotomy procedure after being anesthetized. Following exposure of the kidney beneath ...
      Read Full Article
    9. Optical Coherence Tomography of Human Kidney

      Optical Coherence Tomography of Human Kidney
      Purpose To determine histopathological status of living human kidneys in real time and a noninvasive fashion would be a significant advancement in renal disease diagnosis. Recently we reported that optical coherence tomography has the requisite high spatial resolution to noninvasively determine histopathological changes in rodent kidneys with μm scale resolution. We established whether optical coherence tomography could 1) effectively penetrate the connective tissue capsule surrounding human kidneys, 2) provide a global survey of the human renal surface and 3) determine histopathological changes in human renal microstructure. Materials and Methods Using a high speed optical coherence tomography system equipped with a ...
      Read Full Article
    10. Feature Of The Week 9/6/09: Automated Quantification of Microstructural Dimensions of the Human Kidney using Optical Coherence Tomography

      Feature Of The Week 9/6/09: Automated Quantification of Microstructural Dimensions of the Human Kidney using Optical Coherence Tomography
      Feature Of The Week 9/6/09: Optical coherence tomography (OCT) is a rapidly emerging imaging modality that can non-invasively provide cross-sectional, high-resolution images of tissue morphology in situ and in real-time. Recent development in high-speed OCT enables the acquisition of a large amount of three-dimensional image d
      Read Full Article
    11. Automated quantification of microstructural dimensions of the human kidney using optical coherence tomography (OCT)

      Automated quantification of microstructural dimensions of the human kidney using optical coherence tomography (OCT)
      Optical coherence tomography (OCT) is a rapidly emerging imaging modality that can non-invasively provide cross-sectional, highresolution images of tissue morphology in situ and in real-time. We previously demonstrated that OCT is capable of visualizing characteristic kidney anatomic structures, including blood vessels, uriniferous tubules,glomeruli, and renal capsules on a Munich–Wistar rat model. Because the viability of a donor kidney is closely correlated with its tubular morphology, and a large amount of image datasets are expected when using OCT to scan the entire kidney to provide a global assessment of its viability, it is necessary to develop automatic image analysis ...
      Read Full Article
    12. High-resolution optical coherence tomography imaging of the living kidney

      Optical coherence tomography (OCT) is a rapidly emerging imaging modality that can provide non-invasive, cross-sectional, high-resolution images of tissue morphology in situ and in real-time. In the present series of studies, we used a high-speed OCT imaging system equipped with a frequency-swept laser light source (1.3 m wavelength) to study living kidneys in situ. Adult, male Munich–Wistar rats were anesthetized, a laparotomy was performed and the living kidneys were exposed for in situ observation. We observed the kidneys prior to, during and following exposure to renal ischemia induced by clamping the renal artery. The effects of intravenous mannitol ...
      Read Full Article
    1-12 of 12
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Topics in the News

    1. (12 articles) University of Maryland
    2. (6 articles) Georgetown University
    3. (5 articles) Thorlabs
    4. (2 articles) Boston University
    5. (2 articles) Massachusetts General Hospital
    6. (1 articles) Harvard University
    7. (1 articles) Massachusetts General Hospital
    8. (1 articles) Fujian Normal University
    9. (1 articles) Ludwig Maximilian University of Munich
    10. (1 articles) Massachusetts Institute of Technology
    11. (1 articles) Nara Medical University
    12. (1 articles) University of Maryland
    13. (1 articles) University of Ulsan
    14. (1 articles) FDA
    15. (1 articles) Duke University
    16. (1 articles) University of Queensland
    17. (1 articles) Cleveland Clinic
    18. (1 articles) Kobe University Graduate School of Medicine
  3. Popular Articles

  4. Picture Gallery

    Automated quantification of microstructural dimensions of the human kidney using optical coherence tomography (OCT) Feature Of The Week 9/6/09: Automated Quantification of Microstructural Dimensions of the Human Kidney using Optical Coherence Tomography Optical Coherence Tomography of Human Kidney In vivo, label-free, three-dimensional quantitative imaging of kidney microcirculation using Doppler optical coherence tomography Optical Coherence Tomography of the Living Human Kidney Mannitol Infusion Within 15 Min of Cross-Clamp Improves Living Donor Kidney Preservation Optical coherence tomography (OCT) of a murine model of chronic kidney disease Optical Coherence Tomography of the Aging Kidney Optical coherence tomography and computer-aided diagnosis of a murine model of chronic kidney disease A novel algorithm for multiplicative speckle noise reduction in ex vivo human brain OCT images Volumetric characterization of microvasculature in ex vivo human brain samples by serial sectioning optical coherence tomography Depth of focus extension in optical coherence tomography using ultrahigh chromatic dispersion of zinc selenide