1. All Articles

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    1. Optical Coherence Tomography (OCT) Intravascular Ultrasound (IVUS) Dual Imaging

      Optical Coherence Tomography (OCT) Intravascular Ultrasound (IVUS) Dual Imaging

      Both intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are standardly used and have been extensively studied separately to guide percutaneous coronary intervention and improve long-term outcomes. In this study, the investigators aim to directly compare high-definition IVUS images to OCT in the same patients to determine the differences between each modality as they relate to imaging coronary pathology, with the goal of determining which modality is most appropriate in particular clinical scenarios.

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    2. Comparison of diabetic retinopathy classification using fluorescein angiography and optical coherence tomography angiography

      Comparison of diabetic retinopathy classification using fluorescein angiography and optical coherence tomography angiography

      Purpose To analyse and compare the classification of eyes with diabetic retinopathy using fluorescein angiography (FA) and optical coherence tomography angiography (OCTA) performed either with AngioPlex or AngioVue. Methods This was an observational cross-sectional study of 50 eyes from 26 diabetic subjects. Two independent graders classified the FA angiograms, to assess the presence and severity of several characteristics according to the ETDRS Report 11, and a similar evaluation was performed for each 3×3 mm OCTA image from the superficial retinal layer and for the full retina slab. Results Percentages of non-gradable images for the outline of foveal avascular zone ...

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    3. Temporal ocular coherence tomography-measured changes in anterior chamber angle and diurnal intraocular pressure after laser iridoplasty: IMPACT study

      Temporal ocular coherence tomography-measured changes in anterior chamber angle and diurnal intraocular pressure after laser iridoplasty: IMPACT study

      Aims To evaluate temporal change in anterior chamber angle anatomy following argon laser peripheral iridoplasty (ALPI) in eyes with occludable angles postlaser peripheral iridotomy (LPI) compared with control eyes. Additionally, the effect on diurnal intraocular pressure (DIOP) fluctuation (maximum-minimum IOP) was investigated. Methods Twenty-two patients with bilateral primary angle closure/suspects with gonioscopically occludable anterior chamber angles following LPI were randomised to receive ALPI (n=11) or no further treatment (n=11). Angle opening distance (AOD), trabecular-iris angle, angle recess area and trabecular-iris space area were measured over eight sections with swept-source anterior segment optical coherence tomography and DIOP was ...

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    4. Correlation between clinical, fluorescein angiography and optical coherence tomography findings in clinically significant macular edema

      Correlation between clinical, fluorescein angiography and optical coherence tomography findings in clinically significant macular edema

      Background: Macular edema is an important cause of visual morbidity in diabetic retinopathy. It can be assessed by both fluorescein angiography (FA) and optical coherence tomography (OCT). Aims: To study, if any, correlation exists between FA and OCT patterns in Clinically significant macular edema (CSME). Furthermore, to correlate macular thickness as determined by OCT to best-corrected visual acuity (BCVA). Materials and Methods: This was a prospective study which compared patterns in FA and OCT in patients with CSME. All the patients who were diagnosed as CSME underwent a complete ophthalmic examination and were subjected to FA and OCT. Those with ...

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    5. Limbal Stem Cell Preservation During Proton Beam Irradiation for Diffuse Iris Melanoma

      Limbal Stem Cell Preservation During Proton Beam Irradiation for Diffuse Iris Melanoma

      Purpose: To report the outcome after limbal stem cell preservation during proton beam irradiation for diffuse iris melanoma. Methods: This is a single-case report of diffuse iris melanoma that was managed with proton beam radiation (53 Gy), wherein preemptively harvested superior and inferior limbal stem cells before radiation were replaced after irradiation. Regeneration of the palisades of Vogt and the limbal stem cells was documented by an optical coherence tomography–based imaging protocol. Results: At 24 months after radiation therapy, best-corrected visual acuity was 20/25. The cornea was clear without evidence of limbal stem cell dysfunction. Clinical examination (including ...

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      Mentions: William J. Dupps
    6. Comparison of the Demarcation Line on ASOCT After Simultaneous LASIK and Different Protocols of Accelerated Collagen Crosslinking: A Bilateral Eye Randomized Study

      Comparison of the Demarcation Line on ASOCT After Simultaneous LASIK and Different Protocols of Accelerated Collagen Crosslinking: A Bilateral Eye Randomized Study

      Purpose: To compare the demarcation line depth after 2 different protocols of simultaneous laser in situ keratomileusis and collagen crosslinking (LASIK Xtra). Methods: Twenty-three patients receiving bilateral LASIK Xtra were included in this comparative interventional study. The corneal stroma was soaked with 0.22% riboflavin for 90 seconds before flap repositioning. One eye was then randomized to receive either 18 mW/cm 2 of ultraviolet A irradiation for 120 seconds or for 180 seconds, whereas the fellow eye received the other irradiation duration. The demarcation line on anterior-segment optical coherence tomography and grading of corneal haze on slit lamp were ...

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    7. The new Bruch’s membrane opening – minimum rim width classification improves optical coherence tomography specificity in tilted discs

      The new Bruch’s membrane opening – minimum rim width classification improves optical coherence tomography specificity in tilted discs

      Background and objective: To investigate and compare the false-positive (FP) diagnostic classification of the Bruch’s membrane opening – minimum rim width (BMO-MRW) and retinal nerve fiber layer (RNFL) thickness in healthy eyes with tilted optic disc. Materials and methods: Fifty healthy eyes of 30 participants with tilted optic disc underwent BMO-MRW and RNFL scanning using Spectralis and macular Cirrus optical coherence tomography (OCT) scans. Results: The overall FP rate was significantly lower using BMO-MRW map compared with both RNFL map by Spectralis (8% vs 62%, respectively, P <0.001) and ganglion cell analysis (GCA) map by Cirrus (8% vs 50 ...

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    8. Bio-Photonic Detection and Quantitative Evaluation Method for the Progression of Dental Caries Using Optical Frequency-Domain Imaging Method

      Bio-Photonic Detection and Quantitative Evaluation Method for the Progression of Dental Caries Using Optical Frequency-Domain Imaging Method

      The initial detection of dental caries is an essential biomedical requirement to barricade the progression of caries and tooth demineralization. The objective of this study is to introduce an optical frequency-domain imaging technique based quantitative evaluation method to calculate the volume and thickness of enamel residual, and a quantification method was developed to evaluate the total intensity fluctuation in depth direction owing to carious lesions, which can be favorable to identify the progression of dental caries in advance. The cross-sectional images of the ex vivo tooth samples were acquired using 1.3 μm spectral domain optical coherence tomography system (SD-OCT ...

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    9. Wavelength tunable light source

      Wavelength tunable light source

      To provide a wavelength tunable light source which can both ensure operation speed and reduce a drive voltage. A wavelength tunable light source according to the present invention includes a pair of reflectors at least one of which is a movable reflector, an active layer provided between the pair of reflectors, and a beam on part of which the movable reflector is formed and which is supported by a support member. The beam includes a blade part projecting between the support member and the movable reflector in a direction intersecting a stretching direction of the beam, and a center of ...

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    10. Non-invasive method and apparatus for screening high-quality seeds

      Non-invasive method and apparatus for screening high-quality seeds

      Disclosed is a method and apparatus for the non-invasive selection of high-quality seeds, based on optical coherence tomography, by which pathogen-infected and pathogen-free seeds can be discriminated in a non-invasive manner. The apparatus is operated by the processes of scanning a seed of diagnostic interest in a non-invasive manner using an optical coherence tomographic unit; processing interference signals of the scanned tomographic images to produce tomographic image data of the seed of diagnostic interest; analyzing the tomographic image data; comparing the analyzed tomographic image data with preset reference tomographic image data; diagnosing the seed of diagnostic interest as a pathogen-infected ...

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    11. Establishing compatibility between two- and three-dimensional optical coherence tomography scans

      Establishing compatibility between two- and three-dimensional optical coherence tomography scans

      Advances in optical coherence tomography (OCT) have prompted a transition from time domain OCT, providing 2D OCT images, to spectral domain OCT, which has a 3D imaging capability. Yet conventional technology offers little toward the goal of inter-device compatibility between extant 2D OCT images and newer 3D OCT images for the same or comparable subjects, as in the context of ongoing monitoring the quantitative status of a patient's eyes. The inventive methodology is particularly useful to identify the scan location of tissue in a 2D OCT image within the 3D OCT volumetric data, thereby allowing clinicians to image a ...

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    12. Choriocapillaris evaluation in choroideremia using optical coherence tomography angiography

      Choriocapillaris evaluation in choroideremia using optical coherence tomography angiography

      The choriocapillaris plays an important role in supporting the metabolic demands of the retina. Studies of the choriocapillaris in disease states with optical coherence tomography angiography (OCTA) have proven insightful. However, image artifacts complicate the identification and quantification of the choriocapillaris in degenerative diseases such as choroideremia. Here, we demonstrate a supervised machine learning approach to detect intact choriocapillaris based on training with results from an expert grader. We trained a random forest classifier to evaluate en face structural OCT and OCTA information along with spatial image features. Evaluation of the trained classifier using previously unseen data showed good agreement ...

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    13. Mesenchymal stem cell-laden hybrid scaffold for regenerating subacute tympanic membrane perforation

      Mesenchymal stem cell-laden hybrid scaffold for regenerating subacute tympanic membrane perforation

      ympanic membrane (TM) perforation is one of the most common otology complications. To date, there has not been reported TM regeneration using bioprinted scaffold. The purpose of this study was to evaluate the efficacy and feasibility of bioprinted polycaprolactone/collagen/alginate-mesenchymal stem cell (PCAMSC) scaffolds for the regeneration of subacute TM perforation. Sprague-Dawley rats were used in an animal model of subacute TM perforation. In the experimental group (n = 7), bioprinted 3D PCAMSC scaffold was placed on the perforation. The control group (n = 7) were treated with polycaprolactone/collagen/alginate (PCA) scaffold. Healing time, acoustic-mechanical properties, and morphological analysis were ...

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      Mentions: Byeong Ha Lee
    14. Volumetric laser endomicroscopy in Barrett’s esophagus: interobserver agreement for interpretation of Barrett’s esophagus and associated neoplasia among high-frequency users

      Volumetric laser endomicroscopy in Barrett’s esophagus: interobserver agreement for interpretation of Barrett’s esophagus and associated neoplasia among high-frequency users

      Abstract Background and Aims Targeting neoplasia in Barrett’s esophagus (BE) is challenging. Volumetric laser endomicroscopy (VLE) is a new imaging technique that allows for real time cross-sectional microstructure imaging that can detect BE neoplasia. The interobserver agreement among users in practice is unknown. Methods Eight high-volume users of VLE from different academic centers in the United States evaluated 120-stored VLE images blinded to the endoscopic and clinical findings. There were 30 images for each tissue type: gastric cardia, esophageal squamous mucosa, non-neoplastic BE, and neoplastic BE. Each image with BE had corresponding histology confirming the tissue diagnosis. Each normal ...

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    15. OCT Expanded Clinical Data Analysis (OCT Aboard Space Station)

      OCT Expanded Clinical Data Analysis (OCT Aboard Space Station)

      Vision changes identified in long duration space fliers has led to a more comprehensive clinical monitoring protocol. Optical Coherence Tomography (OCT) was recently implemented on board the International Space Station in 2013. NASA is collaborating with Heidelberg Engineering to expand our current OCT data analysis capability by implementing a volumetric approach. Volumetric maps will be created by combining the circle scan, the disc block scan, and the radial scan. This assessment may provide additional information about the optic nerve and further characterize changes related microgravity exposure. We will discuss challenges with collection and analysis of OCT data, present the results ...

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    16. Morphomechanics of dermis-A method for non-destructive testing of collagenous tissues

      Morphomechanics of dermis-A method for non-destructive testing of collagenous tissues

      Background Collagenous tissues store, transmit and dissipate elastic energy during mechanical deformation. In skin, mechanical energy is stored during loading and then is dissipated, which protects skin from mechanical failure. Thus, energy storage (elastic properties) and dissipation (viscous properties) are important characteristics of extracellular matrices (ECMs) that support the cyclic loading of ECMs without tissue failure. Methods Uniaxial stress-strain measurements on decellularized human dermis have been made and compared to results of a non-destructive technique involving optical coherence tomography (OCT) combined with vibrational analysis. In addition, Poisson's ratio has been determined for tensile deformation of decellularized dermis. Results The ...

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      Mentions: Mark C. Pierce
    17. Optical coherence tomography findings after longitudinal ablation for an underexpanded stent in a heavily calcified lesion: a case repor

      Optical coherence tomography findings after longitudinal ablation for an underexpanded stent in a heavily calcified lesion: a case repor

      Background Heavy coronary artery calcification is responsible for stent underexpansion, which is associated with increased in-stent restenosis. Here we report a case in which optical coherence tomography (OCT) demonstrated that the metal component of an underexpanded stent previously implanted in a heavy calcified lesion had been completely removed after ablation with rotational atherectomy. Case presentation An 83-year-old man with exertional angina was referred to our hospital. Coronary angiography revealed severe stenosis in the proximal portion of the right coronary artery and left circumflex artery and chronic total occlusion (CTO) in the mid portion of the left anterior descending artery (LAD ...

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    18. Lower Tear Meniscus Measurements Using a New Anterior Segment Swept-Source Optical Coherence Tomography and Agreement With Fourier-Domain Optical Coherence Tomography

      Lower Tear Meniscus Measurements Using a New Anterior Segment Swept-Source Optical Coherence Tomography and Agreement With Fourier-Domain Optical Coherence Tomography

      Purpose: To assess intraobserver repeatability and interobserver and intersession reproducibility of lower tear meniscus height (LTMH) measurements obtained using a new anterior segment swept-source optical coherence tomography (SS-OCT) device. Agreement with Fourier-domain (FD) OCT (Spectralis) was also examined. Methods: In an observational cross-sectional study, one eye of 29 healthy subjects was randomly imaged with both devices at our center. Two examiners then randomly measured the LTMH using the software's calipers. To assess intraobserver repeatability and interobserver and intersession reproducibility, within-subject standard deviation (Sw), test-retest repeatability, coefficients of variation (CoV), and intraclass correlation coefficients (ICCs) were calculated. Agreement between both ...

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    19. Accuracy of coronary computed tomography angiography for bioresorbable scaffold luminal investigation: a comparison with optical coherence tomography

      Accuracy of coronary computed tomography angiography for bioresorbable scaffold luminal investigation: a comparison with optical coherence tomography

      To establish the accuracy of coronary computed tomography angiography (CTA) for in-scaffold quantitative evaluation with optical coherence tomography (OCT) as a reference. The translucent backbone of the bioresorbable scaffold allow us to evaluate non-invasively the coronary lumen with coronary CTA. In the ABSORB first-in-man studies, coronary CTA was shown to be feasible for quantitative luminal assessment. Nevertheless, a comparison with an intravascular modality with higher resolution has never been performed. In the ABSORB Cohort B trial, 101 patient with non-complex lesions were treated with the fully biodegradable vascular scaffold. For this analysis, all patients who underwent coronary CTA at 18 ...

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    20. IMAGE QUALITY AND ARTIFACTS ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY: Comparison of Pathologic and Paired Fellow Eyes in 65 Patients With Unilateral Choroidal Melanoma Treated With Plaque Radiotherapy

      IMAGE QUALITY AND ARTIFACTS ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY: Comparison of Pathologic and Paired Fellow Eyes in 65 Patients With Unilateral Choroidal Melanoma Treated With Plaque Radiotherapy

      Purpose: To study image quality and artifacts seen on optical coherence tomography angiography (OCTA). Methods: Sixty-five consecutive patients with unilateral posterior uveal melanoma treated with plaque radiotherapy had OCTA during follow-up. Optical coherence tomography angiography was performed on both the affected and fellow eye. Signal strength and frequency of image artifacts on en face images were compared between affected and fellow eyes. Results: A total of 130 eyes in 65 patients were analyzed, the mean age at time of OCTA was 55 years (median: 56, range: 12-81 years), and 39 (39/65, 60%) were female. Majority of tumors were located ...

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    21. Impact of optical coherence tomography scanning density on quantitative analyses in neovascular age-related macular degeneration

      Impact of optical coherence tomography scanning density on quantitative analyses in neovascular age-related macular degeneration

      Purpose To assess the influence of varying B-scan frame-sampling densities on retinal thickness and volume measurements from spectral domain optical coherence tomography (OCT) in eyes with neovascular age-related macular degeneration (AMD). Methods Volume OCT data (512 × 128 macular cube over 6 × 6   mm) were collected from 39 eyes with neovascular AMD. All 128 B-scans in each image set were manually segmented, allowing quantification of the neurosensory retina, subretinal fluid (SRF), subretinal hyperreflective material (SRHM), and pigment epithelium detachment (PED). Thickness maps were generated for less dense subsets of scans, ranging from every other (64 B-scans) to every 64th (2 B-scans ...

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    22. Renal fluid overload diagnosed by retinal optical coherence tomography scanning

      Renal fluid overload diagnosed by retinal optical coherence tomography scanning

      Fluid overload is one of the major findings in patients with end-stage renal disease. Common findings in fluid overload include shortness of breath, pedal edema, ascites, and pericardial effusion. Rarely, vision loss can be associated with decompensated systemic fluid status. In the following case, we report an unusual case of vision loss due to retinal edema as a result of fluid overload diagnosed and followed to resolution by optical coherence tomography testing.

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    23. Wide-field retinal optical coherence tomography with wavefront sensorless adaptive optics for enhanced imaging of targeted regions

      Wide-field retinal optical coherence tomography with wavefront sensorless adaptive optics for enhanced imaging of targeted regions

      The peripheral retina of the human eye offers a unique opportunity for assessment and monitoring of ocular diseases. We have developed a novel wide-field (>70°) optical coherence tomography system (WF-OCT) equipped with wavefront sensorless adaptive optics (WSAO) for enhancing the visualization of smaller (<25°) targeted regions in the peripheral retina. We iterated the WSAO algorithm at the speed of individual OCT B-scans (~20 ms) by using raw spectral interferograms to calculate the optimization metric. Our WSAO approach with a 3 mm beam diameter permitted primarily low- but also high- order peripheral wavefront correction in less than 10 seconds. In preliminary ...

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    24. Optical Coherence Tomography-Guided Bioresorbable Vascular Scaffold Implantation With Orbital Atherectomy for Calcified Chronic Total Occlusion

      Optical Coherence Tomography-Guided Bioresorbable Vascular Scaffold Implantation With Orbital Atherectomy for Calcified Chronic Total Occlusion

      A 67-year-old male with a past history of hypertension, diabetes, and dyslipidemia complained of neck and jaw pain after walking. Stress myocardial perfusion imaging showed ischemia in the left anterior descending artery (LAD) area. Coronary angiography at an outside hospital revealed a severely calcified chronic total occlusion of the proximal LAD with collateral flow from the right coronary artery. He was referred for revascularization of the LAD. Bilateral femoral access was obtained to perform simultaneous angiography of the left and right coronary artery systems (Figure 1). A 6 French VL3.5 guide was engaged in the left coronary artery. An ...

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