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    1. A benchmark study of automated intra-retinal cyst segmentation algorithms using optical coherence tomography B-scan

      A benchmark study of automated intra-retinal cyst segmentation algorithms using optical coherence tomography B-scan

      Retinal cysts are formed by accumulation of fluid in the retina caused by leakages from inflammation or vitreous fractures. Analysis of the retinal cystic spaces holds significance in detection and treatment of several ocular diseases like age-related macular degeneration, diabetic macular edema etc. Thus, segmentation of intra-retinal cysts and quantification of cystic spaces are vital for retinal pathology and severity detection. In the recent years, automated segmentation of intra-retinal cysts using optical coherence tomography B-scans has gained significant importance in the field of retinal image analysis. The objective of this paper is to compare different intra-retinal cyst segmentation algorithms for ...

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    2. Advances in intraoperative optical coherence tomography for surgical guidance

      Advances in intraoperative optical coherence tomography for surgical guidance

      Translation of optical coherence tomography (OCT) technologies for intraoperative visualization enables in vivo micron-resolution imaging of subsurface tissue structures and image-guided clinical decision-making. Over the last decade, intraoperative OCT has evolved from two-dimensional imaging using handheld probes to include biopsy-needles for minimally invasive deep-tissue imaging, surgical instrumentation using optical feedback for tremor dampening and stabilization, and stereomicroscope integrated systems that provide real-time three- and four-dimensional visualization of surgical maneuvers. In addition, several preliminary studies have demonstrated the feasibility and utility of combining intraoperative OCT imaging with novel image-processing and display methods to implement augmented/virtual reality and robotic surgical guidance ...

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    3. Ocular coherence tomography image data of the retinal laminar structure in a mouse model of oxygen-induced retinopathy

      Ocular coherence tomography image data of the retinal laminar structure in a mouse model of oxygen-induced retinopathy

      The data presented in this article are related to the research paper entitled “Norrin treatment improves ganglion cell survival in an oxygen-induced model of retinal ischemia” (Dailey et al., 2017) [1] This article describes treatment with the human Norrin protein, an atypical Wnt-protein, to improve the survival of retinal ganglion cells in a murine model of Oxygen-Induced Retinopathy (OIR). That study utilized Optical coherence tomography (OCT) to visualize retinal layers at high resolution in vivo , and to quantify changes to nerve fiber layer thickness. Organization of the laminar structure of other retinal layers in this model in vivo , were not ...

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    4. Swept-source optical coherence tomographic findings in eyes with metastatic choroidal tumor

      Swept-source optical coherence tomographic findings in eyes with metastatic choroidal tumor

      Purpose To report the swept-source optical coherence tomographic (OCT) findings in two eyes with choroidal metastases. Observations Two patients with choroidal metastasis were studied. The metastasis was from a breast cancer in Case 1 and from a lung cancer in Case 2. In Case 1, swept-source OCT showed a highly reflective solid tumor with low optical reflective tissues that had replaced the choroidal tissue. Swept-source OCT was able to image the choroidal mass where other fundus imaging methods such as fluorescein angiography did not show the mass. Ophthalmoscopy of Case 2 showed hemorrhages in the inner retina, on the tumor ...

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    5. Projection-resolved optical coherence tomography angiography exhibiting early flow prior to clinically observed retinal angiomatous proliferation

      Projection-resolved optical coherence tomography angiography exhibiting early flow prior to clinically observed retinal angiomatous proliferation

      Purpose The purpose of this study is to analyze early retinal angiomatous proliferation (RAP) utilizing a novel imaging modality, Projection-Resolved Optical Coherence Tomography Angiography (PR-OCTA). Observations Five months prior to the diagnosis of a RAP lesion, cross-sectional PR-OCTA demonstrated flow in the outer retina contiguous with the deep retinal capillary plexus (DCP) and adjacent to a small pigment epithelial detachment. After development of a clinically visible RAP lesion, cross-sectional PR-OCTA demonstrated the RAP lesion connecting DCP and sub-retinal pigment epithelial neovascularization. Conclusions & Importance This is the first report of PR-OCTA demonstrating abnormal flow in the outer retina prior to the ...

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    6. Utility of optical coherence tomography angiography in detecting glaucomatous damage in a uveitic patient with disc congestion: A case report

      Utility of optical coherence tomography angiography in detecting glaucomatous damage in a uveitic patient with disc congestion: A case report

      Purpose To report a case of uveitic glaucoma with congested optic disc where optical coherence tomography angiography (OCT-A) provided diagnostic utility in assessing glaucomatous damage but optical coherence tomography (OCT) alone had limited utility. Observations We report a case of a 33-year-old Caucasian female referred to the USC Roski Eye Institute for uncontrolled intraocular pressure (IOP) in the left eye. She was managed by an outside provider for 6 months, where her IOP ranged from 28 to 42 mm Hg in the left eye on maximally tolerated medical therapy. Her clinical exam was consistent with Herpes family trabeculitis, optic nerve ...

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    7. Optical Frequency Domain Imaging Versus Intravascular Ultrasound in Percutaneous Coronary Intervention (OPINION Trial) : Results From the OPINION Imaging Study

      Optical Frequency Domain Imaging Versus Intravascular Ultrasound in Percutaneous Coronary Intervention (OPINION Trial) : Results From the OPINION Imaging Study

      Objectives We sought to clarify how intravascular ultrasound (IVUS) and optical coherence tomography affect percutaneous coronary intervention (PCI) with current-generation drug-eluting stents in a pre-specified substudy of the OPINION (OPtical frequency domain imaging versus INtravascular ultrasound in percutaneous coronary interventiON) trial, a multicenter, prospective, randomized, noninferiority trial comparing optical frequency domain imaging (OFDI)-guided PCI with IVUS-guided PCI. Background The impact of these 2 imaging modalities in guiding PCI remains unknown. Methods Of 829 patients enrolled in the OPINION trial, 106 were included in the present imaging substudy. Their PCI was guided by either IVUS or OFDI, but all patients ...

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    8. Supercontinuum Generation in Silica Photonic Crystal Fiber at 1.3 μm and 1.65 μm Wavelengths for Optical Coherence Tomography

      Supercontinuum Generation in Silica Photonic Crystal Fiber at 1.3 μm and 1.65 μm Wavelengths for Optical Coherence Tomography

      A new design of all-normal near zero flattened dispersion based on silica photonic crystal fiber is reported to generate an ultra-broadband supercontinuum in the near infrared region. The optimized design offers all normal near zero ultra-flattened dispersion of −7 [ps/nm km] in the wavelengths range [1000 nm–2000 nm]. The investigated design allows ultra-broadband supercontinuum spectra of 600 nm and 1129 nm around wavelengths of 1.3 and 1.65 μm with a short device length of 34 mm and 8.36 mm respectively. The resulting supercontinuums have the potential to enhance the axial resolution of optical coherence tomography ...

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    9. Investigating Intra-Tablet Coating Uniformity With Spectral-Domain Optical Coherence Tomography

      Investigating Intra-Tablet Coating Uniformity With Spectral-Domain Optical Coherence Tomography

      Spectral domain optical coherence tomography (SD-OCT) has recently attracted a lot of interest in the pharmaceutical industry as a fast and non-destructive modality for direct quantification of thin film coatings that cannot easily be resolved with other techniques. While previous studies with SD-OCT have estimated the intra-tablet coating uniformity, the estimates were based on limited number of B-scans. In order to obtain a more accurate estimate, a greater number of B-scans are required that can quickly lead to an overwhelming amount of data. To better manage the data so as to generate a more accurate representation of the intra-tablet coating ...

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    10. Serial Assessment of Tissue Precursors and Progression of Coronary Calcification Analyzed by Fusion of IVUS and OCT

      Serial Assessment of Tissue Precursors and Progression of Coronary Calcification Analyzed by Fusion of IVUS and OCT

      Objectives The aim of this study was to assess calcium growth with fused grayscale intravascular ultrasound (IVUS), IVUS–virtual histology, and optical coherence tomography (OCT) from baseline to 5-year follow-up in patients treated with bioresorbable vascular scaffolds. Background IVUS and OCT have individual strengths in assessing plaque composition and volume. Fusion of images obtained using these methods could potentially aid in coronary plaque assessment. Methods Anatomic landmarks and endoluminal radiopaque markers were used to fuse OCT and IVUS images and match baseline and follow-up. Results Seventy-two IVUS–virtual histology and OCT paired matched cross-sectional in- and out-scaffold segments were fused ...

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    11. Optical coherence tomography (OCT) in optic neuritis and multiple sclerosis

      Optical coherence tomography (OCT) in optic neuritis and multiple sclerosis

      Optical coherence tomography (OCT) is a non-invasive imaging technique routinely used in ophthalmology to visualize and quantify the layers of the retina. It also provides information on optic nerve head topography, peripapillary retinal nerve fiber layer thickness, and macular volume, which correlate with axonal loss. These measurements are of particular interest in optic neuropathies and in multiple sclerosis, and OCT parameters are now used as endpoints in neurologic clinical trials.

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      Mentions: Emory University
    12. Feature definition, analysis and selection for cystoid region characterization in Optical Coherence Tomography

      Feature definition, analysis and selection for cystoid region characterization in Optical Coherence Tomography

      Optical Coherence Tomography (OCT) is, nowadays, a clinical standard imaging technique in opthalmology as it provides more information than other classical modalities as can be, for instance, retinographies. OCT scans show a 3D representation of the real layout of the eye fundus in a non-invasive way, letting clinicians inspect deeply the retinal layers in a cross-sectional visualization. For that reason, OCT scans are commonly used in the study of the retinal morphology and the identification of pathological structures. Among them, an appropriate identification and analysis of any present intraretinal cystoid region is crucial to perform an adequate diagnosis of the ...

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    13. Effect of Post-Dilatation Following Primary PCI With Everolimus-Eluting Bioresorbable Scaffold Versus Everolimus-Eluting Metallic Stent Implantation: An Angiographic and Optical Coherence Tomography TROFI II Substudy

      Effect of Post-Dilatation Following Primary PCI With Everolimus-Eluting Bioresorbable Scaffold Versus Everolimus-Eluting Metallic Stent Implantation: An Angiographic and Optical Coherence Tomography TROFI II Substudy

      Objectives This study sought to investigate the effect of post-dilatation on angiographic and intracoronary imaging parameters in the setting of primary percutaneous coronary intervention comparing the everolimus-eluting bioresorbable scaffold (BRS) with the everolimus-eluting metallic stent (EES). Background Routine post-dilatation of BRS has been suggested to improve post-procedural angiographic and subsequent device-related clinical outcomes. Methods In the ABSORB STEMI TROFI II trial, 191 patients with ST-segment elevation myocardial infarction were randomly assigned to treatment with BRS (n = 95) or EES (n = 96). Minimal lumen area and healing score as assessed by optical coherence tomography at 6 months were compared between BRS- ...

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    14. Long-term Invasive Follow-up of Bioresorbable Vascular Scaffold: Optical Coherence Tomography Assessment of Jailed Side Branches

      Long-term Invasive Follow-up of Bioresorbable Vascular Scaffold: Optical Coherence Tomography Assessment of Jailed Side Branches

      Background Little is known about the long term development of the tissue bridges covering the struts of bioresorbable vascular scaffold (BVS) at the side branches (SB) ostium. This study aims at assessing the resorption process of jailed SB after BVS implantation. Methods We performed both Optical Coherence Tomography (OCT) and Intravascular Ultrasound (IVUS) analysis of 7 patients enrolled in the ABSORB Cohort B trial at our center. Orifice SB area and mean thickness of tissue bridge covering SB were calculated from 2D assessment. The number of SB orifice compartments separated by BRS struts was analyzed by using 3D OCT reconstruction ...

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    15. Data on optical coherence tomography guidance for the management of angiographically intermediate left main bifurcation lesions

      Data on optical coherence tomography guidance for the management of angiographically intermediate left main bifurcation lesions

      The data presented in this article are related to the research article entitled “Optical coherence tomography guidance for the management of angiographically intermediate left main bifurcation lesions: early clinical experience” [1] . In this article we reports details about our clinical experience with frequency domain-optical coherence tomography (FD-OCT) guidance for the management of patients with left main (LM) bifurcation lesions of intermediate angiographic severity. LM patients were assessed by FD-OCT and, on the bases of the findings, managed by myocardial revascularization or conservative treatment (revascularization deferral). The observed outcomes support the feasibility of FD-OCT guidance for LM bifurcated lesions and call ...

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    16. Effect of Early Pitavastatin Therapy on Coronary Fibrous-Cap Thickness Assessed by Optical Coherence Tomography in Patients With Acute Coronary Syndrome : The ESCORT Study

      Effect of Early Pitavastatin Therapy on Coronary Fibrous-Cap Thickness Assessed by Optical Coherence Tomography in Patients With Acute Coronary Syndrome : The ESCORT Study

      Objectives The aim of the present study was to assess the effect of early statin therapy on fibrous-cap thickness in coronary plaques of patients with acute coronary syndrome (ACS) by using optical coherence tomography. Background Statins can contribute to the stabilization of coronary plaques. Methods This is a prospective, randomized, active-controlled, single-center study. Patients with ACS and untreated dyslipidemia were enrolled and randomly allocated (ratio 1:1) to either the early statin group (received pitavastatin 4 mg/day from baseline) or the late statin group (received pitavastatin 4 mg/day from 3 weeks after the baseline). Optical coherence tomography was ...

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    17. Quantitative analysis of retinal perfusion in mice using optical coherence tomography angiography

      Quantitative analysis of retinal perfusion in mice using optical coherence tomography angiography

      Purpose To evaluate repeatability of the quantitative analysis of vessel density in the retinas of healthy mice using optical coherence tomography angiography (OCT-A). Methods Seventeen eyes of seventeen healthy mice aged 10–15 weeks (young) and 75–95 weeks (old) were included in this study. OCT-A was performed using RTVue XR Avanti (Optovue Inc., Fremont, California, USA) under general anaesthesia. The retina was imaged twice using a 3 × 3 mm 2 scan. Retinal thickness and flow density data in the superficial and deep retinal OCT angiograms were extracted and analysed. Results The differences between the flow density values (whole en ...

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    18. Stent implantation and Vascular Healing of a Spontaneous Coronary Artery Dissection assessed by Optical Coherence Tomography in a patient with Acute Coronary Syndrome

      Stent implantation and Vascular Healing of a Spontaneous Coronary Artery Dissection assessed by Optical Coherence Tomography in a patient with Acute Coronary Syndrome

      A 60-year old woman with non-ST-segment elevation myocardial infarction, underwent coronary angiogram combined with optical coherence tomography (OCT) revealing a long dissection in the right coronary artery. The patient experienced peri-procedural chest pain, the electrocardiogram showed ST-segment elevations, and compromised coronary blood flow, why mechanical revascularization with percutaneous coronary intervention (PCI) was indicated. At 1-month follow-up, OCT revealed early, competent vascular healing, and a distal stenosis was treated with PCI. The patient has been asymptomatic since the procedure for three years.

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    19. Massively parallel simulator of optical coherence tomography of inhomogeneous turbid media

      Massively parallel simulator of optical coherence tomography of inhomogeneous turbid media

      Background and objective An accurate and practical simulator for Optical Coherence Tomography (OCT) could be an important tool to study the underlying physical phenomena in OCT such as multiple light scattering. Recently, many researchers have investigated simulation of OCT of turbid media, e.g., tissue, using Monte Carlo methods. The main drawback of these earlier simulators is the long computational time required to produce accurate results. We developed a massively parallel simulator of OCT of inhomogeneous turbid media that obtains both Class I diffusive reflectivity, due to ballistic and quasi-ballistic scattered photons, and Class II diffusive reflectivity due to multiply ...

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    20. Role of optical coherence tomography guided PCI to assess stent malapposition in de-novo coronary lesions

      Role of optical coherence tomography guided PCI to assess stent malapposition in de-novo coronary lesions

      Intra-coronary imaging has revolutionized Percutaneous Coronary Intervention (PCI) by detailed imaging of stented segment. The aim of the present study was to evaluate major stent malapposition by Optical Coherence Tomography (OCT) following standard PCI procedure. Twenty eligible patients for PCI, having reference vessel diameter (RVD) of 2.5 mm to 4.0 mm with ≥ 70% diameter stenosis (DS), lesion length ≤ 40 mm, and more than TIMI-1 flow were included in the study. Patients with cardiogenic shock, left main disease, bypass graft, in-stent restenosis, thrombotic, heavily calcified, chronic total occlusion lesions, TIMI- 0 to 1- coronary blood flow and serum creatinine ...

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      Mentions: St. Jude Medical
    21. Optimization of linear-wavenumber spectrometer for high-resolution spectral domain optical coherence tomography

      Optimization of linear-wavenumber spectrometer for high-resolution spectral domain optical coherence tomography

      Nonlinear detection of the spectral interferograms in wavenumber ( k ) space degrades the depth-dependent signal sensitivity in conventional linear-in- λ spectrometer based spectral domain optical coherence tomography (SDOCT). Linear- k spectrometer enables high sensitivity SDOCT imaging without the need of resampling the digitized non-linear-in- k data. Here we report an effective optimization method for linear- k spectrometer used in a high-resolution SDOCT system. The design parameters of the linear- k spectrometer, including the material of the dispersive prism, the prism vertex angle, and the rotation angle between the grating and prism, are optimized through the numerical simulation of the spectral interference signal ...

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