1. David D. Sampson

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    1. Mentioned In 156 Articles

    2. Detection of localized pulsatile motion in cutaneous microcirculation by speckle decorrelation optical coherence tomography angiography

      Detection of localized pulsatile motion in cutaneous microcirculation by speckle decorrelation optical coherence tomography angiography
      Significance: Pulsatility is a vital characteristic of the cardiovascular system. Characterization of the pulsatility pattern locally in the peripheral microvasculature is currently not readily available and would provide an additional source of information, which may prove important in understanding the pathophysiology of arterial stiffening, vascular ageing, and their linkage with cardiovascular disease development. Aim: We aim to confirm the suitability of speckle decorrelation optical coherence tomography angiography (OCTA) under various ...
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    3. Influence of tissue fixation on depth-resolved birefringence of oral cavity tissue samples

      Influence of tissue fixation on depth-resolved birefringence of oral cavity tissue samples
      Significance: To advance our understanding of the contrast observed when imaging with polarization-sensitive optical coherence tomography (PS-OCT) and its correlation with oral cancerous pathologies, a detailed comparison with histology provided via ex vivo fixed tissue is required. The effects of tissue fixation, however, on such polarization-based contrast have not yet been investigated. Aim: A study was performed to assess the impact of tissue fixation on depth-resolved (i.e., local) birefringence ...
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    4. In vivo imaging of the depth-resolved optic axis of birefringence in human skin

      In vivo imaging of the depth-resolved optic axis of birefringence in human skin
      Recent progress has enabled the reconstruction of the local (i.e., depth-resolved) optic axis (OAx) of biological tissue from measurements made with polarization-sensitive optical coherence tomography (PS-OCT). Here we demonstrate local OAx imaging in healthy human skin in vivo . The images reveal dense, weaving patterns that are imperceptible in OCT intensity tomograms or conventional PS-OCT metrics and that suggest a mesh-like tissue organization, consistent with the morphology of dermal collagen ...
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    5. Change in Leadership at OBEL, The University of Western Australia

      Change in Leadership at OBEL, The University of Western Australia
      Even before I left the University of Kent in 1993, I had noticed how cool optical coherence tomography (OCT) was and how similar it was to some of my own work on coherence multiplexing for communications. Kent was where I did my PhD, obtained my first faculty appointment, and hired my dear friend Adrian Podoleanu to work on telecoms not OCT! Back in Australia in 1995, I arranged for Eric ...
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    6. Jones matrix‐based speckle‐decorrelation angiography using polarization‐sensitive optical coherence tomography

      Jones matrix‐based speckle‐decorrelation angiography using polarization‐sensitive optical coherence tomography
      We show that polarization‐sensitive optical coherence tomography angiography (PS‐OCTA) based on full Jones matrix assessment of speckle decorrelation offers improved contrast and depth of vessel imaging over conventional OCTA. We determine how best to combine the individual Jones matrix elements and compare the resulting image quality to that of a conventional OCT scanner by co‐locating and imaging the same skin locations with closely matched scanning setups. Vessel ...
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    7. Parametric imaging of attenuation by optical coherence tomography: review of models, methods, and clinical translation

      Parametric imaging of attenuation by optical coherence tomography: review of models, methods, and clinical translation
      Significance: Optical coherence tomography (OCT) provides cross-sectional and volumetric images of backscattering from biological tissue that reveal the tissue morphology. The strength of the scattering, characterized by an attenuation coefficient, represents an alternative and complementary tissue optical property, which can be characterized by parametric imaging of the OCT attenuation coefficient. Over the last 15 years, a multitude of studies have been reported seeking to advance methods to determine the OCT ...
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    8. Vectorial birefringence imaging by optical coherence microscopy for assessing fibrillar microstructures in the cornea and limbus

      Vectorial birefringence imaging by optical coherence microscopy for assessing fibrillar microstructures in the cornea and limbus
      The organization of fibrillar tissue on the micrometer scale carries direct implications for health and disease but remains difficult to assess in vivo . Polarization-sensitive optical coherence tomography measures birefringence, which relates to the microscopic arrangement of fibrillar tissue components. Here, we demonstrate a critical improvement in leveraging this contrast mechanism by employing the improved spatial resolution of focus-extended optical coherence microscopy (1.4 m axially in air and 1.6 ...
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    9. Recent progress in optical probing and manipulation of tissue: introduction

      Recent progress in optical probing and manipulation of tissue: introduction
      This feature issue of Biomedical Optics Express represents a cross-section of the most recent work in tissue optics, including exciting developments in tissue optical clearing, deep tissue imaging, optical elastography, nanophotonics in tissue, and therapeutic applications of light, amongst others. A collection of 33 papers provides a comprehensive overview of current research in tissue optics, much of it inspired and informed by the pioneering work of Prof. Valery Tuchin. The ...
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    10. Depth-resolved birefringence imaging of collagen fiber organization in the human oral mucosa in vivo

      Depth-resolved birefringence imaging of collagen fiber organization in the human oral mucosa in vivo
      Stromal collagen organization has been identified as a potential prognostic indicator in a variety of cancers and other diseases accompanied by fibrosis. Changes in the connective tissue are increasingly considered for grading dysplasia and progress of oral squamous cell carcinoma, investigated mainly ex vivo by histopathology. In this study, polarization-sensitive optical coherence tomography (PS-OCT) with local phase retardation imaging is used for the first time to visualize depth-resolved (i.e ...
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    11. Short-time series optical coherence tomography angiography and its application to cutaneous microvasculature

      Short-time series optical coherence tomography angiography and its application to cutaneous microvasculature
      We present a new optical coherence tomography (OCT) angiography method for imaging tissue microvasculature in vivo based on the characteristic frequency-domain flow signature in a short time series of a single voxel. The angiography signal is generated by Fourier transforming the OCT signal time series from a given voxel in multiple acquisitions and computing the average magnitude of non-zero (high-pass) frequency components. Larger temporal variations of the OCT signal caused ...
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    12. Robust reconstruction of local optic axis orientation with fiber-based polarization-sensitive optical coherence tomography

      Robust reconstruction of local optic axis orientation with fiber-based polarization-sensitive optical coherence tomography
      It is challenging to recover local optic axis orientation from samples probed with fiber-based polarization-sensitive optical coherence tomography (PS-OCT). In addition to the effect of preceding tissue layers, the transmission through fiber and system elements, and imperfect system alignment, need to be compensated. Here, we present a method to retrieve the required correction factors from measurements with depth-multiplexed PS-OCT, which accurately measures the full Jones matrix. The correction considers both ...
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    13. Two-photon polymerisation 3D printed freeform micro-optics for optical coherence tomography fibre probes

      Two-photon polymerisation 3D printed freeform micro-optics for optical coherence tomography fibre probes
      Miniaturised optical coherence tomography (OCT) fibre-optic probes have enabled high-resolution cross-sectional imaging deep within the body. However, existing OCT fibre-optic probe fabrication methods cannot generate miniaturised freeform optics, which limits our ability to fabricate probes with both complex optical function and dimensions comparable to the optical fibre diameter. Recently, major advances in two-photon direct laser writing have enabled 3D printing of arbitrary three-dimensional micro/nanostructures with a surface roughness acceptable ...
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    14. 1-15 of 156 1 2 3 4 ... 9 10 11 »
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  2. About David D. Sampson

    David D. Sampson

    David Sampson is the Head of the Optical and Biomedical Engineering Laboratory at the School of Electrical, Electronic and Computer Engineering, Associate Dean of Research, Faculty of Engineering Computing & Mathematics at The University of Western Australia. Professor Sampson has over fifteen years research experience in the fields of optics and photonics, and applications in communications, sensors, and biomedicine. His early research in optical communications centred on the technique of photonic code-division multiple access (CDMA). He continues to be well cited for his contributions, which include the invention of several schemes based on broadband light, practical demonstrations, and the understanding of fundamental limits of the optical version of this widely used communications technique. He has also made contributions to wavelength-division multiplexing transmission and networking, through his studies of schemes based on spectrally slicing broadband light. His early demonstration of the modification of the gain spectrum of an optical amplifier through cascaded sections of differently doped fibres predated an explosion of work on gain flattening in optical amplifiers. At UWA, Prof. Sampson's interests switched to the field of biomedical optical engineering, with an emphasis on imaging and microscopy. His group, the Optical+Biomedical Engineering Laboratory, is involved in activities ranging from the invention and investigation of new optical techniques to the engineering of these techniques into practical instruments for application in biology or medicine. A major emphasis of his research is the coherent imaging modality optical coherence tomography, which continues the theme, begun in his communications research, of exploitation of the coherence properties of broadband light sources. His interest in coherent imaging has recently been extended to Fourier holography. He is also interested in tissue optics and diffuse light propagation in tissue. Outcomes in optical coherence tomography (OCT) span theory, technology and applications. Theoretical contributions include the determination of limits on resolution set by absorption and dispersion in tissue, and an understanding of OCT speckle. Technology outcomes have centered on frequency-domain optical delay line technology, including demonstrations of ultra-long scanning, variable and dynamic dispersion compensation, and achromatic phase shifting. His most significant practical outcome has been in the development of anatomical OCT, which has enabled the first quantitative long-term bedside observations of the human upper airway during sleep, and which is being used to study sleep apnoea. He remains vitally interested in skin cancer diagnosis through low cost means, and has demonstrated a method based on diffuse reflectance spectroscopy to differentiate between malignant melanoma and benign naevi (moles) in vivo. His most recent outcome is the demonstration of a Fourier holographic microscopy technique that can characterise microstructure in biological samples without directly resolving it, making it possible to quantify large sample areas in a single image. Prof. Sampson has formed strong collaborations with biological and medical researchers and clinicians. He is a strong promoter of the importance of interdisciplinary engagement as the basis for a stimulating and productive intellectual environment. Prof. Sampson has attracted career research funding of $10.18M, including $1.70M from industry, and published in excess of 60 journal articles with an average citation rate of 8.9 per paper and in excess of 500 ISI citations. He has been invited to speak at 17 conferences in the last five years. He has previously been an associate editor for the Optical Society of America's Applied Optics (1999-2005) and has been involved in the running of more than 20 conferences, including representing the Asia Pacific for the Optical Fiber Communications conference (1996-1998), serving as Technical Programme Chair for the Asia Pacific Communications conference (1997), co-chairing Focus on Microscopy (2006), and chairing the International Conference on Optical Fiber Sensors in 2008.

  3. Quotes

    1. This is a newsworthy application for those working in the ICU..."Infection is an ever-present risk, and an easier way to check for biofilm could see such checks done more often and infection rates lowered, which would be a great outcome.
      In OCT May Speed Detection Of Pneumonia-Related Bacteria In ICU Patients, Reports Journal Of Biomedical Optics