1. Articles from Guillermo J. Tearney

    1-24 of 180 1 2 3 4 5 6 7 8 »
    1. Systems, methods, and media for multiple reference arm spectral domain optical coherence tomography

      Systems, methods, and media for multiple reference arm spectral domain optical coherence tomography

      In some embodiments, systems, methods, and media for multiple reference arm spectral domain optical coherence tomography are provided which, in some embodiments, includes: a sample arm coupled to a light source; a first reference arm having a first path length; a second reference arm having a longer second path length; a first optical coupler that combines light from the sample arm and the first reference arm; a second coupler that combines light from the sample arm and the second reference arm; and an optical switch comprising: a first input port coupled to the first optical coupler; a second input coupled ...

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    2. Endomicroscopy of the human cochlea using a micro-optical coherence tomography catheter

      Endomicroscopy of the human cochlea using a micro-optical coherence tomography catheter

      Sensorineural hearing loss (SNHL) is one of the most profound public health concerns of the modern era, affecting 466 million people today, and projected to affect 900 million by the year 2050. Advances in both diagnostics and therapeutics for SNHL have been impeded by the human cochlea's inaccessibility for in vivo imaging, resulting from its extremely small size, convoluted coiled configuration, fragility, and deep encasement in dense bone. Here, we develop and demonstrate the ability of a sub-millimeter-diameter, flexible endoscopic probe interfaced with a micro-optical coherence tomography (μOCT) imaging system to enable micron-scale imaging of the inner ear's ...

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    3. Postdoctoral Research Fellowships (Optical Coherence Tomography) at Massachusetts General Hospital

      Postdoctoral Research Fellowships (Optical Coherence Tomography) at Massachusetts General Hospital

      Employer Description Guillermo J. Tearney, M.D., Ph.D. Tearney Lab – Wellman Center for Photomedicine Massachusetts General Hospital Until recently, visualizing the architectural and cellular morphology of human tissue has required histopathological examination. Samples would be excised from the patient, processed, sectioned, stained and viewed under a microscope. In addition to being invasive, time consuming and costly, the static nature of conventional pathology prohibits the study of biological dynamics and function. The Tearney Laboratory at Massachusetts General Hospital has led the way in transforming the current diagnostic paradigm through the invention and translation of new noninvasive, high-resolution optical imaging modalities ...

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    4. Clinical outcomes of low-intensity area without attenuation and cholesterol crystals in non-culprit lesions assessed by optical coherence tomography

      Clinical outcomes of low-intensity area without attenuation and cholesterol crystals in non-culprit lesions assessed by optical coherence tomography

      Background and aims Pathologists have shown that intraplaque hemorrhage contributes to plaque destabilization and is frequently co-located with cholesterol crystals (CC). Optical coherence tomography (OCT)-detected low-intensity area without attenuation (LIA) may represent intraplaque hemorrhage. We aimed to examine the prevalence and impact of OCT-detected LIA + CC in untreated non-culprit lesions (NCLs) on subsequent major adverse cardiac events (MACE). Methods OCT imaged NCLs in the culprit vessel in the patients who underwent OCT-guided percutaneous coronary intervention were included. An NCL was a lesion with >90° of diseased arc (≥0.5 mm intimal thickness), length ≥2 mm, and >5 mm away ...

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    5. Dual-modality optical coherence tomography and fluorescence tethered capsule endomicroscopy

      Dual-modality optical coherence tomography and fluorescence tethered capsule endomicroscopy

      OCT tethered capsule endomicroscopy (TCE) is an emerging noninvasive diagnostic imaging technology for gastrointestinal (GI) tract disorders. OCT measures tissue reflectivity that provides morphologic image contrast, and thus is incapable of ascertaining molecular information that can be useful for improving diagnostic accuracy. Here, we introduce an extension to OCT TCE that includes a fluorescence (FL) imaging channel for attaining complementary, co-registered molecular contrast. We present the development of an OCT-FL TCE capsule and a portable, plug-and-play OCT-FL imaging system. The technology is validated in phantom experiments and feasibility is demonstrated in a methylene blue (MB)-stained swine esophageal injury model ...

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    6. Multi-channel optical fiber rotary junction

      Multi-channel optical fiber rotary junction

      Exemplary apparatus, systems, methods of making, and methods of using a rotary junction are provided. A rotary junction having multiple channels is provided herein. The rotary junction has a first coupling optic and a second coupling optic where the rotating optical fiber or other waveguide comping from the first coupling optic passes through the second coupling optics. 5271076 December 1993 5287423 February 1994 Anthony 5337734 August 1994 5347990 September 1994 Ebling et al.

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    7. Modeling, optimization, and validation of an extended-depth-of-field optical coherence tomography probe based on a mirror tunnel

      Modeling, optimization, and validation of an extended-depth-of-field optical coherence tomography probe based on a mirror tunnel

      The diagnostic capability of high-resolution optical coherence tomography (OCT) may be enhanced by using extended depth-of-field (EDOF) imaging that retains high transverse resolution over long depths. A recently developed mirror-tunnel optical probe design (single-mode fiber to multimode fiber to lens structure) that generates coaxially focused modes has been previously shown to enable EDOF for endoscopic OCT applications. Here, we present ray-tracing optical modeling of this optical configuration, which has the potential to guide performance improvement through optimization. The Huygens wave propagation of the field was traced through probe components with initial lengths. The irradiance along the

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    8. Improved sensitivity roll-off in dual reference, buffered spectral-domain optical coherence tomography

      Improved sensitivity roll-off in dual reference, buffered spectral-domain optical coherence tomography

      Significance: While spectral-domain optical coherence tomography (SD-OCT) is a preferred form of OCT imaging, sensitivity roll-off limits its applicability for certain biomedical imaging applications. Aim: The aim of this work is to extend the imaging range of conventional SD-OCT systems for imaging large luminal organs such as the gastrointestinal tract. Approach: We present an SD-OCT system operating at a center wavelength of 1300 nm that uses two delayed reference arms to reduce sensitivity roll-off and an optical switch and a fiber optic delay line to ensure that the interference spectra are acquired from the same sample time window. Result: The ...

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    9. Apparatus, devices and methods for in vivo imaging and diagnosis

      Apparatus, devices and methods for in vivo imaging and diagnosis

      Exemplary method and apparatus for diagnosing or characterizing an inflammation within an anatomical structure can be provided. For example, using at least one source arrangement, it is possible to provide at least one first electro-magnetic radiation to the anatomical structure at least one first wavelength in vivo. With at least one detector arrangement, it is possible to detect at least one second electro-magnetic radiation at least one second wavelength provided from the anatomical structure. The second radiation can be associated with the first radiation, and the first wavelength can be shorter than the second wavelength. The second radiation can be ...

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    10. Micro-optical coherence tomography for high-resolution morphologic imaging of cellular and nerval corneal micro-structures

      Micro-optical coherence tomography for high-resolution morphologic imaging of cellular and nerval corneal micro-structures

      We demonstrate the highest resolution (1.5×1.5×1 µm) micrometer optical coherence tomography (µOCT) imaging of the morphologic micro-structure of excised swine and non-human primate corneas. Besides epithelial, stromal, and endothelial cell morphology, this report focuses on investigating the most peripheral corneal nerve fibers, the nerve fibers of the subbasal plexus (SBP). Alterations of SBP nerve density and composition are reportedly linked to major neurologic disorders, such as diabetic neuropathy, potentially indicating earliest onsets of denervation. Here, the fine, hyperreflective, epithelial nerve structures located just above Bowman’s membrane, are i) visualized using our µOCT prototype, ii) validated ...

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    11. OCT and CMR for the Diagnosis of Patients Presenting With MINOCA and Suspected Epicardial Causes

      OCT and CMR for the Diagnosis of Patients Presenting With MINOCA and Suspected Epicardial Causes

      Background OCT is able to identify different morphologic features of coronary plaques that are well known causes of MINOCA. Furthermore, CMR has become the gold standard for detection of myocardial infarction in the setting of MINOCA. Methods In a prospective 2-center study, consecutive patients with MINOCA including ECG features of ischemia associated with corresponding WMAs underwent OCT and CMR. Results Forty patients (mean age: 50 ± 11 years, 62.5% male, 32.5% with ST-segment elevation) were enrolled. Coronary arteries were normal on coronary angiography in 10 patients (25%); 18 patients (45%) presented minimal lumen irregularities, whereas the remaining 12 patients ...

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    12. System and method for facilitating manual and/or automatic volumetric imaging with real-time tension or force feedback using a tethered imaging device

      System and method for facilitating manual and/or automatic volumetric imaging with real-time tension or force feedback using a tethered imaging device

      According to exemplary embodiments of the present disclosure, apparatus, device and method can be provided which can provide imaging of biological tissues, e.g., luminal organs in vivo, using optical techniques in an automatic or semiautomatic manner. The exemplary apparatus, device and method can utilize a tethered capsule catheter with a mechanism for manual, semi-automatic or automatic traversing in the luminal organ with a controlled velocity and/or image quality. The exemplary apparatus can include feedback information about tension applied to the catheter during its movement that can be used to adjust velocity and assure patient comfort and safety for ...

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    13. Imaging intracellular motion with dynamic micro-optical coherence tomography

      Imaging intracellular motion with dynamic micro-optical coherence tomography

      This paper describes a new technology that uses 1-µm-resolution optical coherence tomography (µOCT) to obtain cross-sectional images of intracellular dynamics with dramatically enhanced image contrast. This so-called dynamic µOCT (d-µOCT) is accomplished by acquiring a time series of µOCT images and conducting power frequency analysis of the temporal fluctuations that arise from intracellular motion on a pixel-per-pixel basis. Here, we demonstrate d-µOCT imaging of freshly excised human esophageal and cervical biopsy samples. Depth-resolved d-µOCT images of intact tissue show that intracellular dynamics provides a new contrast mechanism for µOCT that highlights subcellular morphology and activity in ...

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    14. Stromal Nerve Imaging and Tracking Using Micro-Optical Coherence Tomography

      Stromal Nerve Imaging and Tracking Using Micro-Optical Coherence Tomography

      urpose : To image, track and map the nerve fiber distribution in excised rabbit corneas over the entire stromal thickness using micro-optical coherence tomography (µOCT) to develop a screening tool for early peripheral neuropathy. Methods : Excised rabbit corneas were consecutively imaged by a custom-designed µOCT prototype and a commercial laser scanning fluorescence confocal microscope. The µOCT images with a field of view of approximately 1 × 1 mm were recorded with axial and transverse resolutions of approximately 1 µm and approximately 4 µm, respectively. In the volumetric µOCT image data, network maps of hyper-reflective, branched structures traversing different stromal compartments were segmented ...

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    15. Devices, systems, methods and storage mediums using full range optical coherence tomography

      Devices, systems, methods and storage mediums using full range optical coherence tomography

      One or more devices, systems, methods and storage mediums for performing continuously, full range optical coherence tomography (OCT) without losing A-lines are provided. Examples of such applications include imaging, evaluating and diagnosing biological objects, such as, but not limited to, for cardio and/or ophthalmic applications, and being obtained via one or more optical instruments, such as, but not limited to, optical probes (e.g., common path probes), catheters, endoscopes, phase shift units (e.g., galvanometer scanner) and bench top systems. Preferably, the OCT devices, systems methods and storage mediums include or involve a phase shift device including at least ...

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    16. All fiber polarization insensitive detection for spectrometer based optical coherence tomography using optical switch

      All fiber polarization insensitive detection for spectrometer based optical coherence tomography using optical switch

      Polarization dependent image artifacts are common in optical coherence tomography imaging. Polarization insensitive detection scheme for swept source based optical coherence tomography systems is well established but is yet to be demonstrated for all fiber spectrometer-based Fourier domain optical coherence tomography systems. In this work, we present an all fiber polarization insensitive detection scheme for spectrometer based optical coherence tomography systems. Images from chicken breast muscle tissue were acquired to demonstrate the effectiveness of this scheme for the conventional Fourier domain optical coherence tomography system.

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    17. 3D cellular-resolution imaging in arteries using few-mode interferometry

      3D cellular-resolution imaging in arteries using few-mode interferometry

      Article Open Access Published: 21 November 2019 3D cellular-resolution imaging in arteries using few-mode interferometry Biwei Yin , Zhonglie Piao , Kensuke Nishimiya , Chulho Hyun , Joseph A. Gardecki , Adam Mauskapf , Farouc A. Jaffer & Guillermo J. Tearney Light: Science & Applications volume 8 , Article number: 104 ( 2019 ) Cite this article Article metrics 3 Altmetric Metrics details Abstract Cross-sectional visualisation of the cellular and subcellular structures of human atherosclerosis in vivo is significant, as this disease is fundamentally caused by abnormal processes that occur at this scale in a depth-dependent manner. However, due to the inherent resolution-depth of focus tradeoff of conventional focusing optics, today ...

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    18. Excess mucus viscosity and airway dehydration impact COPD airway clearance

      Excess mucus viscosity and airway dehydration impact COPD airway clearance

      The mechanisms by which cigarette smoking impairs airway mucus clearance are not well understood. We recently established a ferret model of cigarette smoke-induced chronic obstructive pulmonary disease (COPD) exhibiting chronic bronchitis. We investigated the effects of cigarette smoke on mucociliary transport (MCT). Adult ferrets were exposed to cigarette smoke for 6 months, with in vivo mucociliary clearance (MCC) measured by Tc-labeled DTPA (Tc-DTPA) retention. Excised tracheae were imaged with micro-optical coherence tomography. Mucus changes in primary human airway epithelial cells and ex vivo ferret airways were assessed by histology and particle tracking microrheology. Linear mixed models for repeated measures identified ...

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    19. Co-cultured microfluidic model of the airway optimized for microscopy and micro-optical coherence tomography imaging

      Co-cultured microfluidic model of the airway optimized for microscopy and micro-optical coherence tomography imaging

      We have developed a human bronchial epithelial (HBE) cell and endothelial cell co-cultured microfluidic model to mimic the in vivo human airway. This airway-on-a-chip was designed with a central epithelial channel and two flanking endothelial channels, with a three-dimensional monolayers of cells growing along the four walls of the channel, forming central clear lumens. These cultures mimic airways and microvasculature in vivo . The central channel cells are grown at air-liquid interface and show features of airway differentiation including tight-junction formation, mucus production, and ciliated cells. Combined with novel micro-optical coherence tomography, this chip enables functional imaging of the interior of ...

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    20. Intranasal micro-optical coherence tomography imaging for cystic fibrosis studies

      Intranasal micro-optical coherence tomography imaging for cystic fibrosis studies

      Cystic fibrosis (CF) is a genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. Although impairment of mucociliary clearance contributes to severe morbidity and mortality in people with CF, a clear understanding of the pathophysiology is lacking. This is, in part, due to the absence of clinical imaging techniques capable of capturing CFTR-dependent functional metrics at the cellular level. Here, we report the clinical translation of a 1-μm resolution micro-optical coherence tomography (μOCT) technology to quantitatively characterize the functional microanatomy of human upper airways. Using a minimally invasive intranasal imaging approach, we performed a clinical ...

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    21. Imaging the Human Prostate Gland Using 1-μm-Resolution Optical Coherence Tomography

      Imaging the Human Prostate Gland Using 1-μm-Resolution Optical Coherence Tomography

      Context.— The accuracy of needle biopsy for the detection of prostate cancer is limited by well-known sampling errors. Thus, there is an unmet need for a microscopic screening tool that can screen large regions of the prostate comprehensively for cancer. Previous prostate imaging by optical coherence tomography (OCT) has had insufficient resolution for imaging cellular features related to prostate cancer. We have recently developed micro-optical coherence tomography (μOCT) that generates depth-resolved tissue images at a high frame rate with an isotropic resolution of 1 μm. Objective.— To demonstrate that optical images obtained with μOCT provide cellular-level contrast in prostate specimens ...

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    22. Plaque burden can be assessed using intravascular optical coherence tomography and a dedicated automated processing algorithm: a comparison study with intravascular ultrasound

      Plaque burden can be assessed using intravascular optical coherence tomography and a dedicated automated processing algorithm: a comparison study with intravascular ultrasound

      Aims Plaque burden (PB) measurement using intravascular optical coherence tomography (IVOCT) is currently thought to be inferior to intravascular ultrasound (IVUS). We developed an automated IVOCT image processing algorithm to enhance the external elastic lamina (EEL) contour. Thus, we investigated the accuracies of standard IVOCT and an IVOCT enhancement algorithm for measuring PB using IVUS as the reference standard. Methods and results The EEL-enhancement algorithm combined adaptive attenuation compensation, exponentiation, angular registration, and image averaging using three sequential frames. In two different laboratories with intravascular imaging expertise, PB was quantified on 200 randomized, matched IVOCT and IVUS images by four ...

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    23. Methods, systems, arrangements and computer-accessible medium for providing micro-optical coherence tomography procedures

      Methods, systems, arrangements and computer-accessible medium for providing micro-optical coherence tomography procedures

      Exemplary apparatus and method can be provided for obtaining data regarding a plurality of samples. For example, using at least one arrangement, it is possible to receive interferometric information that is based on radiations provided from a reference and the samples that are provided in respective chambers. Alternatively and/or in addition, based on the interferometric information, it is possible to discriminate between agents to identify a particular agent that affects a particular function within at least one of the samples.

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    1-24 of 180 1 2 3 4 5 6 7 8 »
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