1. Articles from james jiang

    1-21 of 21
    1. Swept source optical coherence microscopy using a 1310 nm VCSEL light source

      Swept source optical coherence microscopy using a 1310 nm VCSEL light source

      We demonstrate high speed, swept source optical coherence microscopy (OCM) using a MEMS tunable vertical cavity surface-emitting laser (VCSEL) light source. The light source had a sweep rate of 280 kHz, providing a bidirectional axial scan rate of 560 kHz. The sweep bandwidth was 117 nm centered at 1310 nm, corresponding to an axial resolution of 13.1 µm in air, corresponding to 8.1 µm (9.6 µm spectrally shaped) in tissue. Dispersion mismatch from different objectives was compensated numerically, enabling magnification and field of view to be easily changed. OCM images were acquired with transverse resolutions between 0 ...

      Read Full Article
    2. Ultrahigh speed endoscopic optical coherence tomography using micromotor imaging catheter and VCSEL technology

      Ultrahigh speed endoscopic optical coherence tomography using micromotor imaging catheter and VCSEL technology

      We developed a micromotor based miniature catheter with an outer diameter of 3.2 mm for ultrahigh speed endoscopic swept source optical coherence tomography (OCT) using a vertical cavity surface-emitting laser (VCSEL) at a 1 MHz axial scan rate. The micromotor can rotate a micro-prism at several hundred frames per second with less than 5 V drive voltage to provide fast and stable scanning, which is not sensitive to the bending of the catheter. The side-viewing probe can be pulled back to acquire a three-dimensional (3D) data set covering a large area on the specimen. The VCSEL provides a high ...

      Read Full Article
    3. High-precision, high-accuracy ultralong-range swept-source optical coherence tomography using vertical cavity surface emitting laser light source

      High-precision, high-accuracy ultralong-range swept-source optical coherence tomography using vertical cavity surface emitting laser light source

      We demonstrate ultralong-range swept-source optical coherence tomography (OCT) imaging using vertical cavity surface emitting laser technology. The ability to adjust laser parameters and high-speed acquisition enables imaging ranges from a few centimeters up to meters using the same instrument. We discuss the challenges of long-range OCT imaging. In vivohuman-eye imaging and optical component characterization are presented. The precision and accuracy of OCT-based measurements are assessed and are important for ocular biometry and reproducible intraocular distance measurement before cataract surgery. Additionally, meter-range measurement of fiber length and multicentimeter-range imaging are reported. 3D visualization supports a class of industrial imaging applications ...

      Read Full Article
    4. Retinal, anterior segment and full eye imaging using ultrahigh speed swept source OCT with vertical-cavity surface emitting lasers

      Retinal, anterior segment and full eye imaging using ultrahigh speed swept source OCT with vertical-cavity surface emitting lasers
      We demonstrate swept source OCT utilizing vertical-cavity surface emitting laser (VCSEL) technology for in vivo high speed retinal, anterior segment and full eye imaging. The MEMS tunable VCSEL enables long coherence length, adjustable spectral sweep range and adjustable high sweeping rate (50–580 kHz axial scan rate). These features enable integration of multiple ophthalmic applications into one instrument. The operating modes of the device include: ultrahigh speed, high resolution retinal imaging (up to 580 kHz); high speed, long depth range anterior segment imaging (100 kHz) and ultralong range full eye imaging (50 kHz). High speed imaging enables wide-field retinal scanning ...
      Read Full Article
    5. MEMS tunable VCSEL light source for ultrahigh speed 60kHz - 1MHz axial scan rate and long range centimeter class OCT imaging

      MEMS tunable VCSEL light source for ultrahigh speed 60kHz - 1MHz axial scan rate and long range centimeter class OCT imaging

      This paper demonstrates new wavelength swept light source technology, MEMS tunable VCSELs, for OCT imaging. The VCSEL achieves a combination of ultrahigh sweep speeds, wide spectral tuning range, flexibility in sweep trajectory, and extremely long coherence length, which cannot be simultaneously achieved with other technologies. A second generation prototype VCSEL is optically pumped at 980nm and a low mass electrostatically tunable mirror enables high speed wavelength tuning centered at ~1310nm with ~110nm of tunable bandwidth. Record coherence length >100mm enables extremely long imaging range. By changing the drive waveform, a single 1310nm VCSEL was driven to sweep at speeds from ...

      Read Full Article
    6. 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
    7. Doppler optical coherence tomography for imaging of brain hemodynamics

      Doppler optical coherence tomography for imaging of brain hemodynamics

      Advanced microscopic techniques enable depth-resolved imaging of changes in blood flow during brain activation. ptical imaging has become an important tool in neuroscience research.1 Using methods such as optical intrinsic signal imaging (OISI), laser-Doppler imaging, and laser-speckle imaging, investigators can record changes in blood flow and blood volume in the brain, as well as alterations in blood oxygen concentration, in response to different types of stimulation. By measuring these changes, they can gain deeper insight into the functioning of the brain, which in turn can contribute to better understanding of a range of behaviors and conditions. However, these techniques ...

      Read Full Article
    8. 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
    9. Ultrahigh-speed volumetric ophthalmic OCT imaging at 800nm and 1050nm

      Ultrahigh-speed volumetric ophthalmic OCT imaging at 800nm and 1050nm
      The performance and imaging characteristics of ultrahigh speed ophthalmic optical coherence tomography (OCT) are investigated. In vivo imaging results are obtained at 850nm and 1050nm using different configurations of spectral and swept source / Fourier domain OCT. A spectral / Fourier domain instrument using a high speed CMOS linescan camera with SLD light source centered at 850nm achieves speeds of ~91,000 axial scans per second with ~3µm axial resolution in tissue. A spectral / Fourier domain instrument using an InGaAs linescan camera with SLD light source centered at 1050nm achieves ~47,000 axial scans per second with ~7µm resolution in tissue. A ...
      Read Full Article
    10. Investigation of pore structure and cell distribution in EH-PEG hydrogel scaffold using optical coherence tomography and fluorescence microscopy

      Investigation of pore structure and cell distribution in EH-PEG hydrogel scaffold using optical coherence tomography and fluorescence microscopy
      Macroporous EH-PEG hydrogels fabricated by porogen-leaching method are characterized by optical coherence tomography (OCT). High-resolution OCT visualizes the microstructures of the engineered tissue scaffolds in threedimensions. It also enables subsequent image processing to investigate several key morphological design parameters for macroporous scaffolds. Image processing algorithms are then presented to automatically quantify the pore size, porosity, and pore interconnectivity. The results indicated that those parameters highly depend on the porogen size. Further, fluorescence imaging was conducted to monitor the population of labeled human mesenchymal stem cells (hMSCs) loaded on the surface of the scaffolds. The results revealed the hMSCs' viability as ...
      Read Full Article
    11. Co-registered optical coherence tomography and fluorescence molecular imaging for simultaneous morphological and molecular imaging

      Abstract. Optical coherence tomography (OCT) provides high-resolution, cross-sectional imaging of tissue microstructure in situ and in real time, while fluorescence molecular imaging (FMI) enables the visualization of basic molecular processes. There is a great deal of interest in combining these two modalities so that the tissue's structural and molecular information can be obtained simultaneously. This could greatly benefit biomedical applications such as detecting early diseases and monitoring therapeutic interventions. In this research, an optical system that combines OCT and FMI was developed. The system demonstrated that it could co-register en face OCT and FMI images with a 2.4 ...
      Read Full Article
    12. 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
    13. Ultrahigh speed spectral/Fourier domain OCT imaging in ophthalmology

      Ultrahigh speed Spectral/Fourier domain ophthalmic OCT imaging at 70,000-312,500 axial scans per second is demonstrated using a high speed CMOS camera at 800 nm. Comparative imaging results of the fovea illustrate the performance tradeoffs between different imaging speeds and spectrometer configurations. Dense 3D volumetric acquisitions show minimal motion artifacts when acquired at 250,000 axial scans per second. The porous structure of the lamina cribrosa is shown in en face images extracted from a dense volumetric acquisition of the optical nerve head acquired at 106, 382 axial scans per second. Rapid repeated volume imaging (4D-OCT) shows blood ...
      Read Full Article
    14. Three-dimensional coregistered optical coherence tomography and line-scanning fluorescence laminar optical tomography

      Three-dimensional coregistered optical coherence tomography and line-scanning fluorescence laminar optical tomography
      We present a combined optical coherence tomography (OCT) and line-scanning fluorescence laminar optical tomography (FLOT) system. This hybrid system enables coregistered structural and molecular imaging in 3D with 10–100 um resolution and millimeter-scale imaging depth. Experimental results on a capillary phantom with fluorescence dye Cy5.5 using an OCT/FLOT imaging system have been demonstrated.
      Read Full Article
    15. Combining optical coherence tomography with fluorescence molecular imaging: towards simultaneous morphology and molecular imaging

      Optical coherence tomography (OCT) provides high-resolution, cross-sectional imaging of tissue microstructure in situ and in real-time, while fluorescence molecular imaging (FMI) enables the visualization of basic molecular processes. There are great interests in combining these two modalities so that the tissue's structural and molecular information can be obtained simultaneously. This could greatly benefit biomedical applications such as detecting early diseases and monitoring therapeutic interventions. In this research, a new optical system that combines OCT and FMI was developed. The system demonstrated that it could co-register en face OCT and FMI images with a 2.4 x 2.4 mm ...
      Read Full Article
    16. Non-invasive in vivo optical biopsy of skin after fractional microablative laser treatment

      We have demonstrated that the 1.3 m Swept-Source Optical Coherence Tomography (SS-OCT) may be used in vivo in a non invasive manner to analyze the characteristics of microablative injuries produced by fractional laser treatments. We have found that the depth of the ablative columns depended approximately linearly on the pulse energy ranging from 180±20 m for 5 mJ laser pulses to 420±60 m for 20 mJ pulses.
      Read Full Article
    17. Ultrahigh speed spectral/Fourier domain ophthalmic OCT imaging

      Ultrahigh speed spectral / Fourier domain optical coherence tomography (OCT) imaging using a CMOS line scan camera with acquisition rates of 70,000 - 312,500 axial scans per second is investigated. Several design configurations are presented to illustrate trade-offs between acquisition speed, sensit ... [Proc. SPIE 7163, 716307 (2009)] published Wed Feb 18, 2009.
      Read Full Article
    18. Live imaging of blood flow in mammalian embryos using Doppler swept-source optical coherence tomography

      Live imaging of blood flow in mammalian embryos using Doppler swept-source optical coherence tomography

      Studying hemodynamic changes during early mammalian embryonic development is critical for further advances in prevention, diagnostics, and treatment of congenital cardiovascular (CV) birth defects and diseases. Doppler optical coherence tomography (OCT) has been shown to provide sensitive measurements of blood flow in avian and amphibian embryos. We combined Doppler swept-source optical coherence tomography (DSS-OCT) and live mouse embryo culture to analyze blood flow dynamics in early embryos. SS-OCT structural imaging was used for the reconstruction of embryo morphology and the orientation of blood vessels, which is required for calculating flow velocity from the Doppler measurements. Spatially and temporally resolved blood ...

      Read Full Article
    19. Ultrahigh speed Spectral / Fourier domain OCT ophthalmic imaging at 70,000 to 312,500 axial scans per second

      Ultrahigh speed Spectral / Fourier domain OCT ophthalmic imaging at 70,000 to 312,500 axial scans per second
      We demonstrate ultrahigh speed spectral / Fourier domain optical coherence tomography (OCT) using an ultrahigh speed CMOS line scan camera at rates of 70,000 - 312,500 axial scans per second. Several design configurations are characterized to illustrate trade-offs between acquisition speed, ... [Opt. Express 16, 15149-15169 (2008)]
      Read Full Article
    20. Speckle variance detection of microvasculature using swept-source optical coherence tomography

      Speckle variance detection of microvasculature using swept-source optical coherence tomography
      Adrian Mariampillai, Beau A. Standish, Eduardo H. Moriyama, Mamta Khurana, Nigel R. Munce, Michael K. Leung, James Jiang, Alex Cable, Brian C. Wilson, I. Alex Vitkin, Victor X. Yang. We report on imaging of microcirculation by calculating the speckle variance of optical coherence tomography (OCT) structural images acquired using a Fourier domain mode-locked swept-wavelength laser. The algorithm calculates interframe speckle variance in two-dimensional and three-dimensional OCT ... [Opt. Lett. 33, 1530-1532 (2008)]
      Read Full Article
    21. 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
    1-21 of 21
  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. (21 articles) Alex E. Cable
    2. (21 articles) Thorlabs
    3. (20 articles) James Y. Jiang
    4. (11 articles) Massachusetts Institute of Technology
    5. (11 articles) James G. Fujimoto
    6. (9 articles) Benjamin M. Potsaid
    7. (8 articles) University of Maryland
    8. (8 articles) Yu Chen
    9. (5 articles) Vivek J. Srinivasan
    10. (5 articles) Vijay Jayaraman
  3. Popular Articles

  4. Picture Gallery

    Speckle variance detection of microvasculature using swept-source optical coherence tomography Ultrahigh speed Spectral / Fourier domain OCT ophthalmic imaging at 70,000 to 312,500 axial scans per second Live imaging of blood flow in mammalian embryos using Doppler swept-source optical coherence tomography Automated quantification of microstructural dimensions of the human kidney using optical coherence tomography (OCT) Investigation of pore structure and cell distribution in EH-PEG hydrogel scaffold using optical coherence tomography and fluorescence microscopy Ultrahigh-speed volumetric ophthalmic OCT imaging at 800nm and 1050nm Optical Coherence Tomography of Human Kidney Doppler optical coherence tomography for imaging of brain hemodynamics MEMS tunable VCSEL light source for ultrahigh speed 60kHz - 1MHz axial scan rate and long range centimeter class OCT imaging Optical Coherence Tomography in Macular Diseases and Glaucoma - Basic Knowledge Optical Coherence Tomography of Magnesium Bioresorbable Scaffold Restenosis Bioresorbable Vascular Scaffold Thrombosis: Clinical and Optical Coherence Tomography Findings