1. Articles from Norman S. Nishioka

    1-19 of 19
    1. Balloon catheter-based radiofrequency ablation monitoring in porcine esophagus using optical coherence tomography

      Balloon catheter-based radiofrequency ablation monitoring in porcine esophagus using optical coherence tomography

      We present a microscopic image guidance platform for radiofrequency ablation (RFA) using a clinical balloon-catheter-based optical coherence tomography (OCT) system, currently used in the surveillance of Barrett’s esophagus patients. Our integrated thermal therapy delivery and monitoring platform consists of a flexible, customized bipolar RFA electrode array designed for use with a clinical balloon OCT catheter and a processing algorithm to accurately map the thermal coagulation process. Non-uniform rotation distortion was corrected using a feature tracking-based technique, which enables robust, frame-to-frame analysis of the temporal fluctuation of the complex OCT signal. With proper noise calibration, precise delineation of the thermal ...

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    2. Optical coherence tomography-guided laser marking with tethered capsule endomicroscopy

      Optical coherence tomography-guided laser marking with tethered capsule endomicroscopy

      Tethered capsule endomicroscopy (TCE) is a new method for performing comprehensive microstructural OCT imaging of gastrointestinal (GI) tract in unsedated patients in a well-tolerated and cost-effective manner. These features of TCE bestow it with significant potential to improve the screening, surveillance and management of various upper gastrointestinal diseases. To achieve clinical adoption of this imaging technique, it is important to validate it with co-registered histology, the current diagnostic gold standard. One such method for co-registering OCT images with histology is laser cautery marking, previously demonstrated using a balloon-centering OCT catheter that operates in conjunction with sedated endoscopy. With laser marking ...

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    3. Clinical Translation of Tethered Confocal Microscopy Capsule for Unsedated Diagnosis of Eosinophilic Esophagitis

      Clinical Translation of Tethered Confocal Microscopy Capsule for Unsedated Diagnosis of Eosinophilic Esophagitis

      Esophagogastroduodenoscopy (EGD) is a widely used procedure, posing significant financial burden on both healthcare systems and patients. Moreover, EGD is time consuming, sometimes difficult to tolerate, and suffers from an imperfect diagnostic yield as the limited number of collected biopsies does not represent the whole organ. In this paper, we report on technological and clinical feasibility of a swallowable tethered endomicroscopy capsule, which is administered without sedation, to image large regions of esophageal and gastric mucosa at the cellular level. To demonstrate imaging capabilities, we conducted a human pilot study (n = 17) on Eosinophilic Esophagitis (EoE) patients and healthy volunteers ...

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    4. Optical coherence tomography in gastroenterology: a review and future outlook

      Optical coherence tomography in gastroenterology: a review and future outlook

      Optical coherence tomography (OCT) is an imaging technique optically analogous to ultrasound that can generate depth-resolved images with micrometer-scale resolution. Advances in fiber optics and miniaturized actuation technologies allow OCT imaging of the human body and further expand OCT utilization in applications including but not limited to cardiology and gastroenterology. This review article provides an overview of current OCT development and its clinical utility in the gastrointestinal tract, including disease detection/differentiation and endoscopic therapy guidance, as well as a discussion of its future applications.

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    5. Automated segmentation and characterization of esophageal wall in vivo by tethered capsule optical coherence tomography endomicroscopy

      Automated segmentation and characterization of esophageal wall in vivo by tethered capsule optical coherence tomography endomicroscopy

      Optical coherence tomography (OCT) is an optical diagnostic modality that can acquire cross-sectional images of the microscopic structure of the esophagus, including Barrett’s esophagus (BE) and associated dysplasia. We developed a swallowable tethered capsule OCT endomicroscopy (TCE) device that acquires high-resolution images of entire gastrointestinal (GI) tract luminal organs. This device has a potential to become a screening method that identifies patients with an abnormal esophagus that should be further referred for upper endoscopy. Currently, the characterization of the OCT-TCE esophageal wall data set is performed manually, which is time-consuming and inefficient. Additionally, since the capsule optics optimally focus ...

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    6. Methods and systems for optical imaging or epithelial luminal organs by beam scanning thereof

      Methods and systems for optical imaging or epithelial luminal organs by beam scanning thereof

      Arrangements, apparatus, systems and systems are provided for obtaining data for at least one portion within at least one luminal or hollow sample. The arrangement, system or apparatus can be (insertable via at least one of a mouth or a nose of a patient. For example, a first optical arrangement can be configured to transceive at least one electromagnetic (e.g., visible) radiation to and from the portion. A second arrangement may be provided at least partially enclosing the first arrangement. Further, a third arrangement can be configured to be actuated so as to position the first arrangement at a ...

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    7. Esophageal-guided biopsy with volumetric laser endomicroscopy and laser cautery marking: a pilot clinical study

      Esophageal-guided biopsy with volumetric laser endomicroscopy and laser cautery marking: a pilot clinical study

      Background Biopsy surveillance protocols for the assessment of Barrett's esophagus can be subject to sampling errors, resulting in diagnostic uncertainty. Optical coherence tomography is a cross-sectional imaging technique that can be used to conduct volumetric laser endomicroscopy (VLE) of the entire distal esophagus. We have developed a biopsy guidance platform that places endoscopically visible marks at VLE-determined biopsy sites. Objective The objective of this study was to demonstrate in human participants the safety and feasibility of VLE-guided biopsy in vivo. Design A pilot feasibility study. Setting Massachusetts General Hospital. Patients A total of 22 participants were enrolled from January ...

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    8. Unsedated imaging of human upper GI tract using tethered capsule endomicroscopy

      Unsedated imaging of human upper GI tract using tethered capsule endomicroscopy

      Background and Aims In order to overcome limitations of endoscopy, we have integrated a microscopic imaging technology into a tethered capsule that can be swallowed. This new technology, which we term tethered capsule endomicroscopy, provides microscopic information from the entire of esophagus as the pill passes through gastrointestinal (GI) tract. Methods Our tethered capsule endomicroscope implements a second-generation, high-speed form of optical coherence tomography termed optical frequency domain imaging that produces microstructural images with a resolution of 30x30x10μm. The capsule has a dimension of 11x25mm and is connected to 160mm long and 0.8mm thin, flexible tether. Unsedated subjects ...

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    9. Tethered capsule endomicroscopy enables less invasive imaging of gastrointestinal tract microstructure

      Tethered capsule endomicroscopy enables less invasive imaging of gastrointestinal tract microstructure

      Here we introduce tethered capsule endomicroscopy, which involves swallowing an optomechanically engineered pill that captures cross-sectional microscopic images of the gut wall at 30 μm (lateral) × 7 μm (axial) resolution as it travels through the digestive tract. Results in human subjects show that this technique rapidly provides three-dimensional, microstructural images of the upper gastrointestinal tract in a simple and painless procedure, opening up new opportunities for screening for internal diseases.

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    10. Barrett's Esophagus Screening Using Balloon-Based Optical Frequency Domain Imaging: A Comparison With Endoscopy

      Abstracts submitted to ASGE 2010. Optical coherence tomography (OCT) is a high-resolution cross-sectional imaging modality that has been shown to accurately differentiate esophageal pathology relevant to screening and surveillance in Barrett's patients. We have previously demonstrated that optical frequency domain imaging (OFDI), a high speed 2nd generation embodiment of OCT, may be used to perform volumetric microscopy of the distal esophagus in patients. In this present study we compare the sensitivity of OFDI to endoscopy for the diagnosis of specialized intestinal metaplasia (SIM), using histopathology as the gold standard.

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    11. Image-guided biopsy in the esophagus through comprehensive optical frequency domain imaging and laser marking: a study in living swine

      Image-guided biopsy in the esophagus through comprehensive optical frequency domain imaging and laser marking: a study in living swine
      Background: Random biopsy esophageal surveillance can be subject to sampling errors, resulting in diagnostic uncertainty. Optical frequency domain imaging (OFDI) is a high-speed, 3-dimensional endoscopic microscopy technique. When deployed through a balloon-centering catheter, OFDI can automatically image the entire distal esophagus (6.0 cm length) in approximately 2 minutes. Objective: To test a new platform for guided biopsy that allows the operator to select target regions of interest on an OFDI dataset, and then use a laser to mark the esophagus at corresponding locations. The specific goals include determining the optimal laser parameters, testing the accuracy of the laser marking ...
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    12. Combined Reflection Confocal Microscopy and Optical Coherence Tomography Imaging of Esophageal Biopsy

      Reflection confocal microscopy (RCM) and optical coherence tomography (OCT) are two non-contact optical imaging technologies that provide images of tissue cellular and architectural morphology, which are both used for histopathologic diagnosis. We have developed a combined RCM and OCT system to compare the accuracy of these imaging techniques for diagnosing esophageal pathology and to evaluate the potential utility of merging the two modalities into a single imaging system. Clinical study was conducted on 32 human esophageal biopsy samples from 23 patients with various histories. Esophageal mucosa was differentiated from gastric mucosa, Barrett's esophagus with intestinal metaplasia was distinguished from ...
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    13. Guided Esophageal Surveillance Biopsy with a Laser Marking Optical Frequency Domain Imaging System

      Optical coherence tomography (OCT) is a high-resolution cross-sectional imaging modality that has been shown to accurately detect and diagnose esophageal pathology. We have previously demonstrated comprehensive microscopic screening of the entire distal esophagus (∼6 cm) using a second generation OCT technology, termed optical frequency domain imaging (OFDI), and a balloon catheter. Esophageal screening with OFDI opens up the possibility of significantly reducing sampling error by providing the capability to target high-risk biopsy sites. In order to guide biopsy during esophageal surveillance, a method for registering neoplastic lesions identified by OFDI with endoscopy is required. We have developed a balloon catheter ...
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    14. Comprehensive microscopy of the esophagus in human patients with optical frequency domain imaging

      Comprehensive microscopy of the esophagus in human patients with optical frequency domain imaging
      Background: Optical coherence tomography (OCT) is a cross-sectional, high-resolution imaging modality that has been shown to accurately differentiate esophageal specialized intestinal metaplasia (SIM) from gastric cardia at the squamocolumnar junction (SCJ) and diagnose high-grade dysplasia and intramucosal carcinoma in patients with SIM. The clinical utility of OCT has been limited, however, by its inability to acquire images over large areas.Objective: The aim of this study was to use recently developed high-speed OCT technology, termed optical frequency domain imaging (OFDI), and a new balloon-centering catheter (2.5 cm diameter) to demonstrate the feasibility of large area, comprehensive optical microscopy of ...
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    15. Comprehensive esophageal microscopy by using optical frequency–domain imaging (with video)

      Comprehensive esophageal microscopy by using optical frequency–domain imaging (with video)
      Background Optical coherence tomography (OCT) has been used for high-resolution endoscopic imaging and diagnosis of specialized intestinal metaplasia, dysplasia, and intramucosal carcinoma of the esophagus. However, the relatively slow image-acquisition rate of the present OCT systems inhibits wide-field imaging and limits the clinical utility of OCT for diagnostic imaging in patients with Barrett's esophagus. Objective This study describes a new optical imaging technology, optical frequency-domain imaging (OFDI), derived from OCT, that enables comprehensive imaging of large esophageal segments with microscopic resolution. Design A prototype OFDI system was developed for endoscopic imaging. The system was used in combination with a ...
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    16. Comprehensive volumetric optical microscopy in vivo

      Comprehensive volumetric optical microscopy in vivo
      Comprehensive volumetric microscopy of epithelial, mucosal and endothelial tissues in living human patients would have a profound impact in medicine by enabling diagnostic imaging at the cellular level over large surface areas. Considering the vast area of these tissues with respect to the desired sampling interval, achieving this goal requires rapid sampling. Although noninvasive diagnostic technologies are preferred, many applications could be served by minimally invasive instruments capable of accessing remote locations within the body. We have developed a fiber-optic imaging technique termed optical frequency-domain imaging (OFDI) that satisfies these requirements by rapidly acquiring high-resolution, cross-sectional images through flexible, narrow-diameter ...
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    17. Optical Coherence Tomography to Identify Intramucosal Carcinoma and High-Grade Dysplasia in Barrett’s Esophagus

      Optical Coherence Tomography to Identify Intramucosal Carcinoma and High-Grade Dysplasia in Barrett’s Esophagus
      Background & Aims: Optical coherence tomography (OCT) is an optical technique that produces high-resolution images of the esophagus during endoscopy. OCT can distinguish specialized intestinal metaplasia (SIM) from squamous mucosa, but image criteria for differentiating intramucosal carcinoma (IMC) and high-grade dysplasia (HGD) from low-grade dysplasia (LGD), indeterminate-grade dysplasia (IGD), and SIM without dysplasia have not been validated. The purpose of this study was to establish OCT image characteristics of IMC and HGD in Barrett’s esophagus. Methods: Biopsy-correlated OCT images were acquired from patients with Barrett’s esophagus undergoing endoscopic surveillance. Two pathologists rendered consensus diagnoses of the biopsy specimens. A ...
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    1-19 of 19
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    1. (19 articles) Massachusetts General Hospital
    2. (19 articles) Harvard University
    3. (18 articles) Norman S. Nishioka
    4. (17 articles) Guillermo J. Tearney
    5. (14 articles) Brett E. Bouma
    6. (11 articles) Melissa J. Suter
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    Comprehensive microscopy of the esophagus in human patients with optical frequency domain imaging Comprehensive volumetric optical microscopy in vivo Comprehensive esophageal microscopy by using optical frequency–domain imaging (with video) Tethered capsule endomicroscopy enables less invasive imaging of gastrointestinal tract microstructure Unsedated imaging of human upper GI tract using tethered capsule endomicroscopy Methods and systems for optical imaging or epithelial luminal organs by beam scanning thereof Automated segmentation and characterization of esophageal wall in vivo by tethered capsule optical coherence tomography endomicroscopy Changes in the OCT angiographic appearance of type 1 and type 2 CNV in exudative AMD during anti-VEGF treatment Optical coherence angiography for pre-treatment assessment and treatment monitoring following photodynamic therapy: a basal cell carcinoma patient study Computational aberration correction in spatiotemporal optical coherence (STOC) imaging A rare entity: Sympathetic ophthalmia presumably after blunt trauma to the phthisical eye and optical coherence tomography angiography metrics to monitor response to treatment Mechanism of fluid leak in non-traumatic corneal perforations: an anterior segment optical coherence tomography study