1. Brett E. Bouma

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    1. Mentioned In 235 Articles

    2. Computational adaptive optics in phase-unstable optical coherence tomography

      Computational adaptive optics in phase-unstable optical coherence tomography
      We present a scheme for correction of separable aberrations in optical coherence tomography (OCT) designed to work with phase unstable systems with no hardware modifications. Our approach, termed SHARP, is based on computational adaptive optics and numerical phase correction and follows from the fact that local phase stability is sufficient for the deconvolution of optical aberrations. We demonstrate its applicability in a raster-scan polygon-laser OCT system with strong phase-jitter noise ...
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    3. Devices and arrangements for performing coherence range imaging using a common path interferometer

      Devices and arrangements for performing coherence range imaging using a common path interferometer
      Devices, arrangements and apparatus adapted to propagate at least one electro-magnetic radiation are provided. In particular, a probe housing, a sample arm section and a reference arm section can be included. For example, the sample arm section can be at least partially situated within the probe housing, and configured to propagate a first portion of the electro-magnetic radiation that is intended to be forwarded to a sample. The reference arm ...
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    4. Linear-in-wavenumber actively-mode-locked wavelength-swept laser

      Linear-in-wavenumber actively-mode-locked wavelength-swept laser
      We report on an akinetic actively-mode-locked wavelength-swept laser (ASL) with a sweep that is highly linear in wavenumber. By tailoring the drive waveform of the intracavity modulator, the wavenumber sweep was further linearized to enable high fidelity frequency-domain interferometric ranging without resampling of the acquired data. Used for catheter-based optical coherence tomography, the ASL showed comparable imaging performance to a state-of-the-art polygon-based wavelength-swept source at a matching sweep rate of ...
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    5. Intravascular Polarimetry: Clinical Translation and Future Applications of Catheter-Based Polarization Sensitive Optical Frequency Domain Imaging

      Intravascular Polarimetry: Clinical Translation and Future Applications of Catheter-Based Polarization Sensitive Optical Frequency Domain Imaging
      Optical coherence tomography (OCT) and optical frequency domain imaging (OFDI) visualize the coronary artery wall and plaque morphology in great detail. The advent of these high-resolution intracoronary imaging modalities has propelled our understanding of coronary atherosclerosis and provided enhanced guidance for percutaneous coronary intervention. Yet, the lack of contrast between distinct tissue types and plaque compositions impedes further elucidation of the complex mechanisms that contribute to acute coronary syndrome (ACS ...
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    6. Artifact Rates for 2D Retinal Nerve Fiber Layer Thickness Versus 3D Neuroretinal Rim Thickness Using Spectral-Domain Optical Coherence Tomography

      Artifact Rates for 2D Retinal Nerve Fiber Layer Thickness Versus 3D Neuroretinal Rim Thickness Using Spectral-Domain Optical Coherence Tomography
      Purpose : To compare the rates of clinically significant artifacts for two-dimensional peripapillary retinal nerve fiber layer (RNFL) thickness versus three-dimensional (3D) neuroretinal rim thickness using spectral-domain optical coherence tomography (SD-OCT). Methods : Only one eye per patient was used for analysis of 120 glaucoma patients and 114 normal patients. For RNFL scans and optic nerve scans, 15 artifact types were calculated per B-scan and per eye. Neuroretinal rim tissue was quantified ...
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    7. Massachusetts General Hospital Receives NIH Grant for Low Risk In Vivo Diagnosis of IPF with Optical Imaging

      Massachusetts General Hospital Receives NIH Grant for Low Risk In Vivo Diagnosis of IPF with Optical Imaging
      ...lly dedicated to supporting Dr. Hariri in this proposal and her transition to independence. In addition, Drs. Brett Bouma and Thomas Colby will serve on Dr. Hariri's research advisory committee and provide further respec...
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    8. Massachusetts General Hospital Receives NIH Grant for Assessing Airway Smooth Muscle Tone in Asthma with Endobronchial Optical Coherence Tomography

      Massachusetts General Hospital Receives NIH Grant for Assessing Airway Smooth Muscle Tone in Asthma with Endobronchial Optical Coherence Tomography
      ...esearch, having been directly involved in seminal studies aimed at translating OCT imaging to the clinic. Dr. Brett Bouma, co-primary mentor, of the Wellman Center for Photomedicine at MGH is one of the key progenitors o...
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    9. A Neural Network Approach to Quantify Blood Flow from Retinal OCT Intensity Time-Series Measurements

      A Neural Network Approach to Quantify Blood Flow from Retinal OCT Intensity Time-Series Measurements
      Many diseases of the eye are associated with alterations in the retinal vasculature that are possibly preceded by undetected changes in blood flow. In this work, a robust blood flow quantification framework is presented based on optical coherence tomography (OCT) angiography imaging and deep learning. The analysis used a forward signal model to simulate OCT blood flow data for training of a neural network (NN). The NN was combined with ...
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    10. Automated noise estimation in polarization-sensitive optical coherence tomography

      Automated noise estimation in polarization-sensitive optical coherence tomography
      Advanced signal reconstruction in polarization-sensitive optical coherence tomography (OCT) frequently relies on an accurate determination of the signal noise floor. However, current methods for evaluating the noise floor are often impractical and subjective. Here we present a method using the degree of polarization uniformity and known speckle intensity statistics to model and estimate the OCT noise floor automatically. We establish the working principle of our method with a series of ...
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    11. Noise and bias in optical coherence tomography intensity signal decorrelation

      Noise and bias in optical coherence tomography intensity signal decorrelation
      Functional optical coherence tomography (OCT) imaging based on the decorrelation of the intensity signal has been used extensively in angiography and is finding use in flowmetry and therapy monitoring. In this work, we present a rigorous analysis of the autocorrelation function, introduce the concepts of contrast bias, statistical bias and variability, and identify the optimal definition of the second-order autocorrelation function (ACF) g (2) to improve its estimation from limited ...
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    12. Forward multiple scattering dominates speckle decorrelation in whole-blood flowmetry using optical coherence tomography

      Forward multiple scattering dominates speckle decorrelation in whole-blood flowmetry using optical coherence tomography
      Quantitative blood flow measurements using optical coherence tomography (OCT) have a wide potential range of medical research and clinical applications. Flowmetry based on the temporal dynamics of the OCT signal may have the ability to measure three-dimensional flow profiles regardless of the flow direction. State-of-the-art models describing the OCT signal temporal statistics are based on dynamic light scattering (DLS), a model which is inherently limited to single scattering regimes. DLS ...
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    13. 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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    14. Stable multi-megahertz circular-ranging optical coherence tomography at 1.3 µm

      Stable multi-megahertz circular-ranging optical coherence tomography at 1.3 µm
      In Fourier-domain optical coherence tomography (OCT), the finite bandwidth of the acquisition electronics constrains the depth range and speed of the system. Circular-ranging (CR) OCT methods use optical-domain compression to surpass this limit. However, the CR-OCT system architectures of prior reports were limited by poor stability and were confined to the 1.55 m wavelength range. In this work, we describe a novel CR-OCT architecture that is free from these ...
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    15. 1-15 of 235 1 2 3 4 ... 14 15 16 »
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  2. About Brett E. Bouma

    Brett E. Bouma

    Brett E. Bouma is an Associate Professor at the Wellman Center for Photomedicine at the Massachusetts General Hospital. Research focus is on the development of novel optical instrumentation and methods that address challenges in clinical medicine and basic biological research. Light is uniquely well suited for non-invasively interrogating the microscopic structure, molecular composition, and biomechanical properties of biological tissues. Realizing these capabilities in a practical instrument requires a multidisciplinary approach, focused on specific challenges, that integrates advanced concepts from physics, engineering and material science with biology and clinical experience. The location of our laboratory on the campus of a major clinical research hospital fosters regular interaction across these disciplinary areas.

  3. Quotes

    1. We expect to see commercial devices available in a one- to two-year time frame.
      In America wakes up to 3-D human coronary artery imaging
    2. For diagnosing early-stage disease, the clinician has been basically looking for a needle in a haystack; so sampling only a few microscopic points of an organ, as we could with OCT, is clearly not sufficient.
      In Optical Technique Provides Improved 'Virtual Biopsies' Of Internal Surfaces
    3. One of the most exciting concepts would be to directly link OFDI with the delivery of therapy, such as laser treatment for early cancer.
      In Optical Technique Provides Improved 'Virtual Biopsies' Of Internal Surfaces