Articles that mention Osman O. Ahsen -Optical Coherence Tomography News

Osman O. Ahsen

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1. Mentioned In 22 Articles
2. Correction of circumferential and longitudinal motion distortion in high-speed catheter/endoscope ...
  
  Explore OSA | OSA Publishing Dec 9 2020 Gastroenterology
  
  Catheter/endoscope-based optical coherence tomography (OCT) is a powerful modality that visualizes structural information in luminal organs. Increases in OCT speed have reduced motion artifacts by enabling acquisition faster than or comparable to the time scales of physiological motion. However motion distortion remains a challenge because catheter/endoscope OCT imaging involves both circumferential and longitudinal scanning of tissue. This paper presents a novel image processing method to estimate and correct ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Harvard University
3. Tethered capsule en face optical coherence tomography for imaging Barrett’s oesophagus in unsedated patients
  
  Explore BMJ Open Gastroenterology Sep 6 2020 Gastroenterology , Probes
  
  Objective Barretts oesophagus (BE) screening outside the endoscopy suite can identify patients for surveillance and reduce mortality. Tethered capsule optical coherence tomography (OCT) can volumetrically image oesophageal mucosa in unsedated patients and detect features of BE. We investigated ultrahigh-speed tethered capsule swept-source OCT (SS-OCT), improved device design, developed procedural techniques and measured capsule contact, longitudinal pullback non-uniformity and patient toleration. Design OCT was performed in 16 patients prior to endoscopic ...
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  Mentions: Thorlabs Massachusetts General Hospital Hiroshi Mashimo
4. Tethered capsule en face optical coherence tomography for imaging Barrett’s esophagus in unsedated patients
  
  Explore arxiv.org May 26 2020 Gastroenterology
  
  Objective Detection of Barretts esophagus (BE) at points of care outside the endoscopy suite may improve screening access and reduce esophageal adenocarcinoma mortality. Tethered capsule optical coherence tomography (OCT) can volumetrically image esophageal mucosa and detect BE in unsedated patients. We investigated ultrahigh-speed tethered capsule, swept-source OCT (SS-OCT) in unsedated patients, improved device design, developed procedural techniques, measured how capsule contact and longitudinal pullback non-uniformity affect coverage, and assessed patient ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
5. Feature Of The Week 10/08/2018: Clinical Utility of Ultrahigh-Speed Endoscopic Optical Coherence Tomography in Gastroenterology
  
  Explore Optical Coherence Tomography News Oct 7 2018 Gastroenterology
  
  ...ith neoplasia and pathogenesis. For more information see recent Article1 , Article2 , and Article3 . Courtesy Osman O. Ahsen from the Massachusetts Institute of Technology . Barrett’s esophagus (BE) surveillance is limit...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
6. Assessment of Barrett’s esophagus and dysplasia with ultrahigh-speed volumetric en face and cross-sectional optical coherence tomography
  
  Explore thieme-connect.de Sep 30 2018 Gastroenterology
  
  Background This study aimed to evaluate the use of ultrahigh-speed volumetric en face and cross-sectional optical coherence tomography (OCT) with micromotor catheters for the in vivo assessment of Barretts esophagus and dysplasia. Methods 74 OCT datasets with correlated biopsy/endoscopic mucosal resection histology (49 nondysplastic Barretts esophagus [NDBE], 25 neoplasia) were obtained from 14 patients with Barretts esophagus and a history of dysplasia and 30 with NDBE. The associations between ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
7. Cycloid scanning for wide field optical coherence tomography endomicroscopy and angiography in vivo
  
  Explore OSA | OSA Publishing Jan 16 2018 Gastroenterology , Probes
  
  Devices that perform wide field-of-view (FOV) precision optical scanning are important for endoscopic assessment and diagnosis of luminal organ disease such as in gastroenterology. Optical scanning for in vivo endoscopic imaging has traditionally relied on one or more proximal mechanical actuators, limiting scan accuracy and imaging speed. There is a need for rapid and precise two-dimensional (2D) microscanning technologies to enable the translation of benchtop scanning microscopies to in vivo ...
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  Mentions: Johns Hopkins University Massachusetts Institute of Technology James G. Fujimoto
8. Ultrahigh-speed endoscopic optical coherence tomography and angiography enables delineation of lateral margins of endoscopic mucosal resection: a case report
  
  Explore SAGE Journals Nov 28 2017 Gastroenterology
  
  Endoscopic mucosal resection (EMR) is a common technique for resecting dysplastic lesions in Barretts esophagus (BE), stomach, and colon, 1 but precise delineation of dysplastic margins before resection and verification of complete removal after resection remain challenging. 2 , 3 Endoscopic optical coherence tomography (OCT) enables three-dimensional visualization of tissue microstructure and is commercially available as Volumetric Laser Endomicroscopy (NinePoint Medical, Bedford, MA, USA). 4 , 5 We recently developed an ultrahigh-speed ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
9. Endoscopic forward-viewing optical coherence tomography and angiography with MHz swept source
  
  Explore OSA | OSA Publishing Aug 9 2017 Gastroenterology , Probes
  
  Endoscopic optical coherence tomography (OCT) instruments are mostly side viewing and rely on at least one proximal scan, thus limiting accuracy of volumetric imaging and en face visualization. Previous forward-viewing OCT devices had limited axial scan speeds. We report a forward-viewing fiber scanning 3D-OCT probe with 900 m field of view and 5 m transverse resolution, imaging at 1 MHz axial scan rate in the human gastrointestinal tract. The probe ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
10. Assessment of the radiofrequency ablation dynamics of esophageal tissue with optical coherence tomography
  
  Explore SPIE | Journal Jul 10 2017 Gastroenterology
  
  Radiofrequency ablation (RFA) is widely used for the eradication of dysplasia and the treatment of early stage esophageal carcinoma in patients with Barretts esophagus (BE). However, there are several factors, such as variation of BE epithelium (EP) thickness among individual patients and varying RFA catheter-tissue contact, which may compromise RFA efficacy. We used a high-speed optical coherence tomography (OCT) system to identify and monitor changes in the esophageal tissue architecture ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Harvard University
11. Endoscopic optical coherence tomography angiography microvascular features associated with dysplasia in Barrett's esophagus: a pilot study (with video)
  
  Explore Elsevier Health Feb 3 2017 Gastroenterology , Oncology
  
  Background and Aims Angiogenesis is associated with neoplastic progression of Barretts esophagus (BE). Volumetric optical coherence tomography angiography (OCTA) visualizes subsurface microvasculature without exogenous contrast agents. We investigated the association of OCTA microvascular features with low-grade dysplasia (LGD) and high-grade dysplasia (HGD). Methods Fifty-two patients undergoing BE surveillance or endoscopic eradication therapies for dysplasia were imaged using volumetric OCTA and corresponding histological diagnoses obtained, to yield 97 data sets (non-dysplastic ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
12. Volumetric Mapping of Barrett’s Esophagus and Dysplasia With en face Optical Coherence Tomography Tethered Capsule
  
  Explore Nature Publishing Group Nov 9 2016 Gastroenterology
  
  To the Editor: Dysplasia in Barretts Esophagus (BE) is patchy ( 1 ) and sometimes missed by random biopsies. Optical coherence tomography (OCT) can image large areas of the esophagus; however, slow imaging speeds in earlier studies limited visualization to cross-sections. Cross-sectional OCT detected high-grade dysplasia with sensitivity / specificity of ~80 % ( 2 , 3 ). Tethered OCT capsules were demonstrated for cross-sectional imaging in unsedated screening to detect BE ( 4 , 5 ). Our group recently ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
13. Feature Of The Week 03/08/2015: Endoscopic Optical Coherence Angiography Enables Three Dimensional Visualization of Subsurface Microvasculature
  
  Explore Optical Coherence Tomography News Mar 7 2015 Gastroenterology
  
  Endoscopic imaging technologies such as confocal laser endomicroscopy (CLE) and narrowband imaging (NBI) have been used to investigate vascular changes as hallmarks of early cancer in the GI tract. However, the limited frame rate and field of view make CLE imaging sensitive to motion artifacts, whereas NBI has limited resolution and visualizes only the surface vascular pattern. Endoscopic optical coherence tomography (OCT) enables high speed volumetric imaging of subsurface features ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
14. Endoscopic Optical Coherence Angiography Enables Three Dimensional Visualization of Subsurface Microvasculature
  
  Explore Gastroenterology Dec 1 2014 Gastroenterology
  
  ... and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts , Osman O. Ahsen x Osman O....
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
15. Ultrahigh speed endoscopic optical coherence tomography for gastroenterology
  
  Explore opticsinfobase.org Nov 29 2014 Gastroenterology
  
  We describe an ultrahigh speed endoscopic swept source optical coherence tomography (OCT) system for clinical gastroenterology using a vertical-cavity surface-emitting laser (VCSEL) and micromotor imaging catheter. The system had a 600 kHz axial scan rate and 8 m axial resolution in tissue. Imaging was performed with a 3.2 mm diameter imaging catheter at 400 frames per second with a 12 m spot size. Three-dimensional OCT (3D-OCT) imaging was performed ...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
16. Correction of rotational distortion for catheter-based en face OCT and OCT angiography
  
  Explore opticsinfobase.org Oct 10 2014
  
  ...ng Liang, Tsung-Han Tsai, Benjamin Potsaid, Hiroshi Mashimo, and James G. Fujimoto »View Author Affiliations Osman O. Ahsen,^1 Hsiang-Chieh Lee,^1 Michael G. Giacomelli,^1 Zhao Wang,^1 Kaicheng Liang,^1 Tsung-Han Tsai,^...
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  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
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