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    1. First-in-Man study evaluating the safety and efficacy of a second generation biodegradable polymer sirolimus-eluting stent in the treatment of patients with de novo coronary lesions: Clinical, angiographic, and OCT outcomes of CREDIT-1

      First-in-Man study evaluating the safety and efficacy of a second generation biodegradable polymer sirolimus-eluting stent in the treatment of patients with de novo coronary lesions: Clinical, angiographic, and OCT outcomes of CREDIT-1

      Objective: To evaluate the preliminary safety and efficacy of the EXCEL II stent system. Background: Although the first biodegradable polymer drug-eluting stent (BP-DES), EXCEL, was launched nearly a decade ago, in-stent restenosis and stent thrombosis remain pertinent clinical problems in practice. A new cobalt-chromium BP-DES EXCEL II has been developed with the aim of improving stent safety and efficacy. Methods: Forty-five patients with single de novo native coronary lesions were enrolled and randomized to two groups in a 2:1 ratio, the 4-month follow-up group (n=30) and the 12-month follow-up group (n=15). All patients underwent percutaneous coronary intervention ...

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    2. Optical coherence tomography vs intravascular ultrasound in the evaluation of observer variability and reliability in the assessment of stent deployment: The OCTIVUS Study

      Optical coherence tomography vs intravascular ultrasound in the evaluation of observer variability and reliability in the assessment of stent deployment: The OCTIVUS Study

      Abstract Objectives : To compare the variability in the assessment of coronary stents among interventional cardiologists (readers) using Optical Coherence Tomography (OCT) and Intravascular ultrasound (IVUS). Background : IVUS is established and validated in the evaluation of coronary stent. For cardiologists without core lab expertise, the utility of IVUS is limited by image quality. OCT yields higher image resolution, however, the consistency with which these readers interpret OCT images has not been fully evaluated or compared with IVUS. Methods : OCT and IVUS image sets (5 pairs) obtained following stent placement were reviewed by readers with clinical experience with both modalities. Parameters assessed ...

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    3. Impact of coronary artery stent edge dissections on long-term clinical outcome in patients with acute coronary syndrome: An Optical Coherence Tomography Study

      Impact of coronary artery stent edge dissections on long-term clinical outcome in patients with acute coronary syndrome: An Optical Coherence Tomography Study

      Aims: The purpose of the present study was to assess the incidence, predictors and long term prognosis of stent edge dissections identified by (OCT) after the implantation of bare metal (BMS) and drug eluting stents (DES). Methods and results: We studied 74 patients who underwent percutaneous coronary intervention (PCI) because of an acute coronary syndrome. Edge dissections were found in 29 of 74 patients (39.1%). Independent predictors of edge dissections were: the presence of ST-elevation myocardial infarction (STEMI) (p=0.005, odds ratio 11.78; 95% Cl 2.06-67.10), the small reference lumen diameter ( p= 0.009, odds ...

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    4. Noninvasive depth-resolved optical measurements of the tympanic membrane and middle ear for differentiating otitis media

      Noninvasive depth-resolved optical measurements of the tympanic membrane and middle ear for differentiating otitis media

      Objective/Hypothesis In this study, optical coherence tomography (OCT) is used to noninvasively and quantitatively determine tympanic membrane (TM) thickness and the presence and thickness of any middle-ear biofilm located behind the TM. These new metrics offer the potential to differentiate normal, acute, and chronic otitis media (OM) infections in pediatric subjects. Study Design Case series with comparison group. Methods The TM thickness of 34 pediatric subjects was acquired using a custom-built, handheld OCT system following a traditional otoscopic ear exam. Results Overall thickness (TM and any associated biofilm) was shown to be statistically different for normal, acute, and chronic ...

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    5. Effect of hyaluronic acid on tear film thickness as assessed with ultra-high resolution optical coherence tomography

      Effect of hyaluronic acid on tear film thickness as assessed with ultra-high resolution optical coherence tomography

      Purpose The aim of this study was to assess the effect of a single drop of hyaluronic acid on tear film thickness (TFT) in healthy subjects. Methods Sixteen healthy subjects (eight male/eight female) aged between 20 and 36 years were included in this randomized, double-masked placebo-controlled study. One eye received a single dose of hyaluronic acid (Olixia pure ® ; Croma Pharma, Korneuburg, Austria) eye drops, and the fellow eye received physiologic saline solution as placebo control. The study eye was chosen randomly. TFT as measured with a custom-built Fourier-domain optical coherence tomography (FD-OCT) system was the main outcome variable and ...

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    6. Identification of layers in optical coherence tomography of skin: comparative analysis of experimental and Monte Carlo simulated images

      Identification of layers in optical coherence tomography of skin: comparative analysis of experimental and Monte Carlo simulated images

      Background/purpose The goal of the study is comparative analysis of the layers in OCT images and the morphological structure of skin with thick and thin epidermis. Methods We analyzed the difference between skin with thin and thick epidermis in two ways. The first approach consisted in determination of the thicknesses of layers of skin with thin and thick epidermis of different localizations from experimental OCT images. The second approach was to develop numerical models fitting experimental OCT images based on Monte Carlo simulations revealing structure and optical parameters of layers of skin with thick and thin epidermis. Results The ...

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    7. A case report of differentiating staphylococcal scalded skin syndrome and toxic epidermal necrolysis by optical coherence tomography

      A case report of differentiating staphylococcal scalded skin syndrome and toxic epidermal necrolysis by optical coherence tomography

      Background Staphylococcal scalded skin syndrome (SSSS) and toxic epidermal necrolysis (TEN) both present with acute onset, high morbidity and significant mortality. Rapid diagnosis is therefore of importance. The aim of this study was to investigate and compare the presentation of these diseases using optical coherence tomography (OCT). Methods Two male patients with bullous diseases, SSSS and TEN, respectively, were photographed digitally, examined using dermoscopy, OCT scanned and subsequently biopsied in the said order. Results The bullous skin was visualized by OCT showing two distinct images: the SSSS-patient displayed superficial hyporefletive flaccid structures with a split high in the thickened (0 ...

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    8. Three dimensional mesoscale analysis of translamellar cross-bridge morphologies in the annulus fibrosus using optical coherence tomography

      Three dimensional mesoscale analysis of translamellar cross-bridge morphologies in the annulus fibrosus using optical coherence tomography

      The defining characteristic of the annulus fibrosus (AF) of the intervertebral disc (IVD) has long been the lamellar structures that consist of highly ordered collagen fibers arranged in alternating oblique angles from one layer to the next. However, a series of recent histologic studies have demonstrated that AF lamellae contain elastin- and type VI collagen-rich secondary “cross-bridge” structures across lamellae. In this study, we use optical coherence tomography (OCT) to elucidate the three-dimensional (3-D) morphologies of these translamellar cross-bridges in AF tissues. Mesoscale volumetric images by OCT revealed a 3-D network of heterogeneously distributed cross-bridges. The results of this study ...

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    9. Enhanced depth imaging-optical coherence tomography of the choroid in moderate and severe primary angle-closure glaucoma

      Enhanced depth imaging-optical coherence tomography of the choroid in moderate and severe primary angle-closure glaucoma

      Purpose To compare the choroidal thickness (CT) in eyes with moderate and severe primary angle-closure glaucoma (PACG) with the eyes of healthy controls. Methods Fifty-nine patients (59 eyes) with PACG and 56 age-matched normal subjects underwent macular CT scanning using enhanced depth imaging–optical coherence tomography. The subjects with PACG were further classified as having moderate [−12 dB ≤ visual field mean deviation (VF-MD) ≤ −6 dB] or severe (VF-MD < −12 dB) glaucoma. The average CT of the PACG eyes at each location was compared to that of normal eyes. Results The CT was significantly increased in moderate and severe PACG eyes ...

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    10. Using optical coherence tomography to rapidly phenotype and quantify congenital heart defects associated with prenatal alcohol exposure

      Using optical coherence tomography to rapidly phenotype and quantify congenital heart defects associated with prenatal alcohol exposure

      Background : The most commonly used method to analyze congenital heart defects involves serial sectioning and histology. However, this is often a time-consuming process where the quantification of cardiac defects can be difficult due to problems with accurate section registration. Here we demonstrate the advantages of using optical coherence tomography, a comparatively new and rising technology, to phenotype avian embryo hearts in a model of Fetal Alcohol Syndrome where a binge-like quantity of alcohol/ethanol was introduced at gastrulation. Results : The rapid, consistent imaging protocols allowed for the immediate identification of cardiac anomalies, including ventricular septal defects and misaligned/missing vessels ...

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    11. Comparative analysis of corneal measurements obtained from a Scheimpflug camera and an integrated Placido-optical coherence tomography device in normal and keratoconic eyes

      Comparative analysis of corneal measurements obtained from a Scheimpflug camera and an integrated Placido-optical coherence tomography device in normal and keratoconic eyes

      Purpose To assess the agreement between a Scheimpflug camera (Pentacam) and a combined Placido-optical coherence tomography device (Visante OMNI) in measuring corneal curvature, thickness and elevation values in normal and keratoconic eyes. Methods Corneal measurements of 110 normal eyes (one eye per subject) and 70 keratoconic eyes were obtained from both devices and compared. Agreement was determined using the Bland–Altman analysis 95% limits of agreement (LoA). Results The Pentacam measured significantly greater keratometry readings in the flattest (K1) and steepest meridians (K2) in normal and keratoconic eyes. The 95% LoA in normal eyes were −0.32 to 0.59 ...

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    12. Multimodality imaging of attenuated plaque using grayscale and virtual histology intravascular ultrasound and optical coherent tomography

      Multimodality imaging of attenuated plaque using grayscale and virtual histology intravascular ultrasound and optical coherent tomography

      Background Although attenuated plaque is a marker for plaque vulnerability, the quantification and its implication have not been known. Methods Multimodality pre-procedural imaging using grayscale intravascular ultrasound (IVUS), virtual histology-IVUS (VH-IVUS) and optical coherence tomography (OCT) were performed in 115 coronary lesions with diameter stenosis (DS) >30% and plaque burden ≥50% and compared the diagnostic accuracies for detecting thin-cap fibroatheromas (TCFA). Results A maximal arc of attenuation (40MHz IVUS) ≥29.0° was the cut-off for predicting VH-TCFA (sensitivity 74%, specificity 66%); and OCT-TCFA (sensitivity 89%, specificity 64%), while a maximal arc attenuation≥29.0° (20MHz IVUS) showed a poor sensitivity ...

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    13. Clinical assessment of non carious cervical lesion using swept-source optical coherence tomography

      Clinical assessment of non carious cervical lesion using swept-source optical coherence tomography

      ( A ) We determined the attenuation coeffcient (μ t ) threshold of SS-OCT signal for the detection of demineralization (1.21) from in vitro study. DEM: demineralized dentin, sound: sound dentin. ( B ) Using the μ t threshold, we observed NCCLs in vivo to detect the demineralization in cervical dentin. SS-OCT scanning was performed along the red line. ( C ) SS-OCT image obtained along the red line in B. In SS-OCT, brightness of dentin beneath the NCCL was increased (arrow) compared with intact zone. The cervical dentin was slightly demineralized (μ t : 1.25). e: enamel, d: dentin, g: gingiva. Non-carious cervical lesions (NCCLs) involve various forms ...

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    14. In vivo molecular mapping of the tumor microenvironment in an azoxymethane-treated mouse model of colon carcinogenesis

      In vivo molecular mapping of the tumor microenvironment in an azoxymethane-treated mouse model of colon carcinogenesis

      Background and Objective Development of miniaturized imaging systems with molecular probes enables examination of molecular changes leading to initiation and progression of colorectal cancer in an azoxymethane (AOM)-induced mouse model of the disease. Through improved and novel studies of animal disease models, more effective diagnostic and treatment strategies may be developed for clinical translation. We introduce use of a miniaturized multimodal endoscope with lavage-delivered fluorescent probes to examine dynamic microenvironment changes in an AOM-treated mouse model. Study Design/Materials and Methods The endoscope is equipped with optical coherence tomography (OCT) and laser induced fluorescence (LIF) imaging modalities. It is ...

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    15. Optical density filters modeling media opacities cause decreased SD-OCT retinal layer thickness measurements with inter- and intra-individual variation

      Optical density filters modeling media opacities cause decreased SD-OCT retinal layer thickness measurements with inter- and intra-individual variation

      Purpose To assess the effect of media opacities on thickness measurements of the peripapillary retinal nerve fibre layer (pRNFL) and macular inner retinal layer (mIRL) performed with spectral-domain optical coherence tomography (SD-OCT) using a set of filters with known optical density. Methods Spectral-domain optical coherence tomography volume scans of the optic disc and the macular area were performed in 18 healthy volunteers, using Topcon-3DOCT-1000 Mark II. A set of five filters with optical density ranging from 0.04 to 0.69 was used. The correlation was calculated between the percentage change in thickness measurements (%ΔpRNFL and %ΔmIRL) and the change ...

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    16. Chemical Strategies for the Development of Multimodal Imaging Probes Using Nanoparticles (Book Chapter)

      Chemical Strategies for the Development of Multimodal Imaging Probes Using Nanoparticles (Book Chapter)

      This chapter focuses on the most recently reported nanoparticle agents that have been demonstrated in vivo . It describes the general methods of chemical conjugations, silanisation, and electrostatic adsorption. The chapter examines the recent use of nanoparticles that incorporate a fluorescent dye and a magnetic nanoparticle together. The combination of near-infrared (NIR) and magnetic resonance imaging (MRI) modalities and in vivo characterisation has been executed in two ways: attaching an organic NIR dye to a superparamagnetic iron oxide nanoparticle (SPION); and combining SPIONs with a materials-based NIR fluorescent species such as a quantum dot or multilayered gold/silica nanoparticles. Upconversion luminescence ...

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    17. Dual optical modality endoscopic imaging of cancer development in the mouse colon

      Dual optical modality endoscopic imaging of cancer development in the mouse colon

      Background and Objective We utilize a miniature, dual-modality endoscope that combines fluorescence-based surface magnifying chromoendoscopy (SMC) and optical coherence tomography (OCT) to follow the anatomical changes that occur during adenoma development in the mouse colon. Materials and Methods Twenty-five mice were treated with the carcinogen azoxymethane (AOM) to induce tumor development in the distal colon, or were treated with saline as control, and were imaged over six months. OCT detects adenoma number with high sensitivity and specificity and can measure lesion size. In methylene blue-lavaged colons, SMC detects changes in the colonic crypts. SMC images of control mouse colons exhibit ...

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    18. Cross-evaluation of optimal glycerol concentration to enhance optical tissue clearing efficacy

      Cross-evaluation of optimal glycerol concentration to enhance optical tissue clearing efficacy

      Background/aims The efficacy of light therapeutic and diagnostic applications can be enhanced by employing optical tissue clearing (OTC) agents to minimize light scattering in tissue. This study aimed to investigate the optimal concentration of glycerol, so that it can be efficiently used as an OTC agent in dermatology. Methods Glycerol was topically applied to avoid the possibility of edema that could be caused by dermal injection. The efficacy of glycerol was quantitatively evaluated for various concentrations using optical coherence tomography (OCT) to evaluate light scattering and ultrasound imaging modality to evaluate collagen dissociation. Results The intensity in the OCT ...

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    19. Optical coherence elastography for tissue characterization: a review

      Optical coherence elastography for tissue characterization: a review

      Optical coherence elastography (OCE) represents the frontier of optical elasticity imaging techniques and focuses on the micro-scale assessment of tissue biomechanics in 3D that is hard to achieve with traditional elastographic methods. Benefit from the advancement of optical coherence tomography, and driven by the increasing requirements in nondestructive biomechanical characterization, this emerging technique recently has experienced a rapid development. In this paper, we start with the description of the mechanical contrast that has been employed by OCE and review the state-of-the-art techniques based on the reported applications and discuss the current technical challenges, emphasizing the unique role of OCE in ...

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    20. Combining region-based and imprecise boundary-based cues for interactive medical image segmentation

      Combining region-based and imprecise boundary-based cues for interactive medical image segmentation

      In this paper, we present an approach combining both region selection and user point selection for user assisted segmentation, as either an enclosed object or an open curve, and investigate the method of image segmentation in specific medical applications (user assisted segmentation of the media adventitia border in IVUS images, and lumen border in OCT images), and then demonstrate the method with generic images to show how it could be utilised in other types of medical image, and is not limited to the applications described.. The proposed method combines point based soft constraint on object boundary and stroke based regional ...

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    21. Real-time, noninvasive optical coherence tomography of cross-sectional living cell-sheets in vitro and in vivo

      Real-time, noninvasive optical coherence tomography of cross-sectional living cell-sheets in vitro and in vivo

      Cell sheet technology has a history of application in regenerating various tissues, having successfully completed several clinical trials using autologous cell sheets. Tomographic analysis of living cell sheets is an important tool in the field of cell sheet-based regenerative medicine and tissue engineering to analyze the inner structure of layered living cells. Optical coherence tomography (OCT) is commonly used in ophthalmology to noninvasively analyze cross-sections of target tissues at high resolution. This study used OCT to conduct real-time, noninvasive analysis of living cell sheet cross sections. OCT showed the internal structure of cell sheets in tomographic images synthesized with backscatter ...

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    22. Macular parameters of Stratus optical coherence tomography for assessing glaucoma in high myopia

      Macular parameters of Stratus optical coherence tomography for assessing glaucoma in high myopia

      Background The aim was to assess the macular parameters of glaucoma in highly myopic subjects. Methods In a retrospective study, we enrolled 72 highly myopic eyes (spherical equivalent up to -6.00 D), of which 31 had early to moderate glaucoma and 41 formed a control group. The diagnosis of early to moderate glaucoma was based on glaucomatous visual-field defects with a mean deviation better than -12 dB. All patients underwent imaging with Stratus optical coherence tomography. We subsequently performed analysis for macular volume and thickness parameters between two groups. Results Using Stratus optical coherence tomography, we found significantly lower ...

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