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    1. In Situ Circular Compression and Doppler Optical Coherence Tomography Studies on Effects of Diabetic Mellitus on Vesa Nervonum of Sciatic Nerve

      In Situ Circular Compression and Doppler Optical Coherence Tomography Studies on Effects of Diabetic Mellitus on Vesa Nervonum of Sciatic Nerve

      Diabetes mellitus is one of the most common diseases in the world and can causemany types of neuropathies, and even mortality. It is therefore important to understand how diabetes mellitus alters the mechanical properties of nerve tissues and their blood vessels. In this study, in situ compression-and-hold circular compression tests were applied to the sciatic nerves of both diabetic rats and normal rats. Doppler optical coherence tomography ( Doppler OCT ) was then utilized to monitor the configuration of the arterioles in two groups of rats. The force data acquired in the compression tests were fitted by using Fung’s quasi-linear viscoelastic ...

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    2. Associations of macular thickness in spectral-domain OCT with ocular and systemic cardiovascular parameters - The MIPH Eye & Health Study

      Associations of macular thickness in spectral-domain OCT with ocular and systemic cardiovascular parameters - The MIPH Eye & Health Study

      Purpose Beyond in-vivo histological analysis of retinal tissue, optical coherence tomography (OCT) allows quantitative image analysis. This study evaluates associations of macular retinal thickness measured with spectral-domain OCT (SD-OCT) and ocular and systemic cardiovascular parameters in adult subjects. Methods An epidemiological cross-sectional study was performed in the staff of a European high-tech company. Examination of known cardiovascular risk factors including biochemical blood analysis was performed, and ocular parameters such as refraction, tonometry, SD-OCT imaging of the macula and cornea, and fundus photography were evaluated. Retinal thickness measurements were evaluated according to the ETDRS grid. Associations of macular retinal thickness and ...

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    3. Probing regional mechanical properties of embryonic tissue using microindentation and optical coherence tomography

      Probing regional mechanical properties of embryonic tissue using microindentation and optical coherence tomography

      Physical forces regulate morphogenetic movements and the mechanical properties of embryonic tissues during development. Such quantities are closely interrelated, as increases in material stiffness can limit force-induced deformations and vice versa. Here we present a minimally invasive method to quantify spatiotemporal changes in mechanical properties during morphogenesis. Regional stiffness is measured using microindentation, while displacement and strain distributions near the indenter are computed from the motion of tissue labels tracked from 3-D optical coherence tomography (OCT) images. Applied forces, displacements, and strain distributions are then used in conjunction with finite-element models to estimate regional material properties. This method is applicable ...

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    4. Hemodynamic Flow Visualization of Early Embryonic Great Vessels Using μPIV

      Hemodynamic Flow Visualization of Early Embryonic Great Vessels Using μPIV

      Microparticle image velocimetry (μPIV) is an evolving quantitative methodology to closely and accurately monitor the cardiac flow dynamics and mechanotransduction during vascular morphogenesis. While PIV technique has a long history, contemporary developments in advanced microscopy have significantly expanded its power. This chapter includes three new methods for μPIV acquisition in selected embryonic structures achieved through advanced optical imaging: (1) high-speed confocal scanning of transgenic zebrafish embryos, where the transgenic erythrocytes act as the tracing particles; (2) microinjection of artificial seeding particles in chick embryos visualized with stereomicroscopy; and (3) real-time, time-resolved optical coherence tomography acquisition of vitelline vessel flow profiles ...

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    5. Recent Trends in Multimodal Optical Coherence Tomography. II. The Correlation-Stability Approach in OCT Elastography and Methods for Visualization of Microcirculation

      Recent Trends in Multimodal Optical Coherence Tomography. II. The Correlation-Stability Approach in OCT Elastography and Methods for Visualization of Microcirculation

      The second part of this paper continues the discussion of possibilities for combining functionally different types of biomedical characterization of tissues using optical coherence tomography (OCT). In the first part, polarization-sensitive imaging and conventional approaches to elastographic mapping in OCT were considered. Here, we consider an unconventional approach to elastographic mapping based on the analysis of variability of OCT images of the deformed tissue, omitting the stage of the displacement-field reconstruction. We also discuss methods for quantification of blood flow and visualization of microvasculature, some of which have much in common with the elastographic approach based on the analysis of ...

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    6. Novel insights provided by spectral-domain coherent tomography in pediatric ophthalmology

      Novel insights provided by spectral-domain coherent tomography in pediatric ophthalmology

      Tilted disk syndrome (TDS) is observed in approximately 1 % to 2 % of the population. This percentage appears to be highly variable according to the clinical and imaging features retained for establishing the accurate diagnosis. It is of paramount importance to distinguish isolated tilted optic disk from TDS. This syndrome has a number of alternative nomenclatures such as the nasal fundus ectasia syndrome, inversion of the optic disk, inverse myopia, and dysversion of the optic disk. TDS may be a variant of colobomatous defects. The definition of TDS has often been inaccurate in many studies which did not take account of ...

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    7. Optical coherence tomography in the diagnosis of basal cell carcinoma

      Optical coherence tomography in the diagnosis of basal cell carcinoma

      Since its introduction in dermatology in the late 1990s optical coherence tomography (OCT) has been used to study many skin diseases, in particular non-melanoma skin cancer and it s precursors. Special attention has been paid to superficial basal cell carcinoma (BCC), and a number of smaller observational studies have been published. The diagnostic criteria for BCC of these studies are systematically reviewed. A systemic review of English language studies was performed using PubMed, Google Scholar and Royal Danish Library, to search for primary papers on OCT and BCC. The references of retrieved papers were searched by hand for further relevant ...

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    8. Study of cystoid macular edema by optical coherent tomography following uneventful cataract surgery

      Study of cystoid macular edema by optical coherent tomography following uneventful cataract surgery

      The objective of this paper is to study the incidence of cystoid macular edema (CME) using optical coherence tomography (OCT) following uneventful small incision cataract surgery (SICS) and phacoemulsification. This was a descriptive, prospective study where 200 patients undergoing cataract surgery were randomly divided into two groups over a period of 1 year. Patients undergoing uneventful small incision cataract surgery were included in group I and patient undergoing uneventful phacoemulsification were included in group II, with 100 patients in each group. Preoperative assessment included best corrected visual acuity, detailed anterior segment and posterior segment evaluation, and intraocular pressure measurement. Macular ...

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    9. Fluorescein angiography versus spectral domain optical coherence tomography in idiopathic juxtafoveal retinal telangiectasia

      Fluorescein angiography versus spectral domain optical coherence tomography in idiopathic juxtafoveal retinal telangiectasia

      Dear Editor, We thank Dr. Singh and colleagues for their interest in our article, titled “Diagnosis of subretinal neovascularization associated with idiopathic juxtafoveal retinal telangiectasia—fluorescein angiography versus spectral-domain optical coherence tomography” [ 1 ]. We appreciate their concerns and here are the point-to-point responses to their comments. Comment 1. Color fundus photo has low sensitivity in detecting SRNV secondary to IJRT type 2A. This implies that a number of SRNV would be missed on color fundus photos. However, in this study, a color fundus photo is being used as a reference for presence or absence of SRNV, and this would result ...

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    10. Differentiating allergic and irritant contact dermatitis by high-definition optical coherence tomography: a pilot study

      Differentiating allergic and irritant contact dermatitis by high-definition optical coherence tomography: a pilot study

      Differentiation of allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD) is important because of different management requirements. Various non-invasive tests have been used in an attempt to improve diagnosis. In irritant dermatitis, thickening of the epidermis has been a constant finding. High-Definition Optical Coherence Tomography (HD-OCT) is a non-invasive real-time three-dimensional imaging technique with cellular resolution for which an adapted algorithmic method for pattern analysis discriminating inflammatory skin diseases has been proposed. The aim of this study was threefold. (1) To evaluate the correlation between HD-OCT features and clinical scores of allergic and irritant patch test reactions. (2) To ...

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    11. Measurement of retinal nerve fiber layer and macular ganglion cell-inner plexiform layer with spectral-domain optical coherence tomography in patients with optic nerve head drusen

      Measurement of retinal nerve fiber layer and macular ganglion cell-inner plexiform layer with spectral-domain optical coherence tomography in patients with optic nerve head drusen

      Purpose To evaluate the effect of optic nerve head drusen (ONHD) on the retinal nerve fiber layer (RNFL) and macular ganglion cell–inner plexiform layer (GCIPL) using Cirrus optical coherence tomography (OCT). Methods Fifty-seven eyes of thirty patients with ONHD and thirty-eight eyes of twenty age-matched and sex-matched control subjects underwent circumpapillary and macular scanning using Cirrus OCT. The percentages of eyes with abnormal GCIPL and RNFL values according to the Cirrus normative data were analysed and compared. Results Overall, eyes with ONHD showed abnormally reduced values for average and minimum GCIPL thicknesses in 35 % and 45 % of cases compared ...

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    12. Retinal vessel diameter measurements by spectral domain optical coherence tomography

      Retinal vessel diameter measurements by spectral domain optical coherence tomography

      Purpose To describe a spectral domain optical coherence (OCT)-assisted method of measuring retinal vessel diameters. Methods All Patients with an OCT circle scan centered at the optic nerve head using a Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany) were retrospectively reviewed. Individual retinal vessels were identified on infrared reflectance (IR) images and given unique labels both on IR and spectral domain OCT (SD-OCT). Vessel width and vessel types obtained by IR were documented as ground truth. From OCT, measurements of each vessel, including horizontal vessel contour diameter, vertical vessel contour diameter, horizontal hyperreflective core diameter, and reflectance shadowing width, were ...

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    13. Correlation between optical coherence tomography-derived intraluminal parameters and fractional flow reserve measurements in intermediate grade coronary lesions

      Correlation between optical coherence tomography-derived intraluminal parameters and fractional flow reserve measurements in intermediate grade coronary lesions

      Background Fractional flow reserve (FFR) measurements accurately assess functional relevance in intermediate grade coronary lesions. A significant relationship between hemodynamic stenosis severity and optical coherence tomography (OCT)-derived intraluminal dimensions has recently been demonstrated. However, morphologic thresholds to identify significant stenoses are variable and exploration of this correlation in patients with diabetes mellitus (DM) remains currently incomplete. This study aimed at comparing the diagnostic value of intraluminal parameters as determined by OCT to predict FFR ≤0.8 in lesions of patients with versus without DM. Methods In 100 patients (DM = 56, non-DM = 44) with 142 coronary de novo lesions (DM ...

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    14. Early axonal damage detection by ganglion cell complex analysis with optical coherence tomography in nonarteritic anterior ischaemic optic neuropathy

      Early axonal damage detection by ganglion cell complex analysis with optical coherence tomography in nonarteritic anterior ischaemic optic neuropathy

      Purpose To investigate the ability of ganglion cell complex (GCC) analysis by optical coherence tomography (OCT) to detect early axonal damage in nonarteritic anterior ischaemic optic neuropathy (NAION), and to assess the relationship of GCC measurements with visual field defects and function parameters. Methods Twenty-two patients with NAION participated in this retrospective case-series study. Patients underwent spectral-domain OCT measurement of retinal nerve fibre layer (RNFL) and GCC average and minimum thicknesses, best-corrected visual acuity, Ishihara test and Humphrey visual field (SITA Standard 24–2). These measurements were recorded in the acute (2–6 weeks after the ischaemic episode) and chronic ...

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    15. Experimental and Modeling Study of Human Tympanic Membrane Motion in the Presence of Middle Ear Liquid

      Experimental and Modeling Study of Human Tympanic Membrane Motion in the Presence of Middle Ear Liquid

      Vibration of the tympanic membrane (TM) has been measured at the umbo using laser Doppler vibrometry and analyzed with finite element (FE) models of the human ear. Recently, full-field TM surface motion has been reported using scanning laser Doppler vibrometry, holographic interferometry, and optical coherence tomography. Technologies for imaging human TM motion have the potential to lead to using a dedicated clinical diagnosis tool for identification of middle ear diseases. However, the effect of middle ear fluid (liquid) on TM surface motion is still not clear. In this study, a scanning laser Doppler vibrometer was used to measure the full-field ...

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    16. Relationship between cholesterol crystals and culprit lesion characteristics in patients with stable coronary artery disease: an optical coherence tomography study

      Relationship between cholesterol crystals and culprit lesion characteristics in patients with stable coronary artery disease: an optical coherence tomography study

      Aims Some recent studies have reported the role of cholesterol crystals (ChCs) in plaque rupture in patients with coronary artery disease. We used optical coherence tomography (OCT) to investigate the characteristics of coronary plaques that were associated with derived ChCs. Methods We evaluated 101 subjects with stable coronary artery disease who underwent OCT. We compared the OCT findings of the culprit lesions with ChCs to those without ChCs and investigated the background characteristics. Results ChCs were observed in culprit lesions of 39 patients. The frequencies of spotty calcification, microchannel structure, and lipid-rich plaque were significantly higher in patients with ChCs ...

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    17. Side branch healing patterns of the Tryton dedicated bifurcation stent: a 1-year optical coherence tomography follow-up study

      Side branch healing patterns of the Tryton dedicated bifurcation stent: a 1-year optical coherence tomography follow-up study

      The bare-metal Tryton Side Branch (SB) Stent™ (Tryton Medical, Durham, NC, USA) is used with a drug-eluting stent (DES) in the main branch (MB) to treat bifurcation lesions. It is argued that a drug-eluting Tryton-version is needed to improve clinical outcomes, although previous registries have shown good clinical results. More insights in neo-intimal hyperplasia (NIH) growth patterns of the Tryton treatment strategy are needed to decide if and where to drug-coat the stent. Ten patients returned for follow-up angiography (mean follow-up time 393 ± 103 days) and optical coherence tomography (OCT) pullbacks from the MB were obtained in all patients and ...

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    18. Intracoronary Optical Coherence Tomography: Insights from Clinical Research—What Do We Need to Learn?

      Intracoronary Optical Coherence Tomography: Insights from Clinical Research—What Do We Need to Learn?

      Optical coherence tomography (OCT) is a high-resolution technology for imaging of biological tissues that has shown tremendous potential for intracoronary use. Based on near-infrared light rather than ultrasound, catheter-based OCT provides cross-sectional images of the vessel wall and related devices in a histology-like manner. At present, OCT is primarily being used in research to better characterize and understand the pathophysiology of vulnerable plaques and to study the acute and long-term effects of coronary stent implantation. The present review provides the interventional cardiologist with a summary of the clinical research involving OCT, with an emphasis on specific challenges and how these ...

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      Mentions: Maria D. Radu
    19. Spectral-domain optical coherence tomography findings in pediatric tilted disc syndrome

      Spectral-domain optical coherence tomography findings in pediatric tilted disc syndrome

      Purpose To report a novel spectral-domain optical coherence tomography (SD-OCT) finding in children affected by tilted disc syndrome (TDS), and to correlate it with early visual field defects. Methods Patients between 5 and 17 years old with TDS were enrolled in this study. The diagnosis of TDS was made by stereoscopic fundus photography, when the upper edge of the optic disc protruded anteriorly relative to its lower edge. All eyes were examined with 12 radial SD-OCT B-scans of 12 mm centered on the optic disc; the fundus area encompassing the optic nerve was additionally scanned using several vertical and horizontal ...

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    20. Optical coherence tomography-guided classification of epiretinal membranes

      Optical coherence tomography-guided classification of epiretinal membranes

      To study and classify epiretinal membranes (ERMs) based on spectral domain optical coherence tomography (SD-OCT) findings. One hundred and twelve patients with ERMs were examined clinically and underwent OCT examination. The anatomical structure of the macula and vitreoretinal interface was studied. ERMs were classified in two categories: A, with posterior vitreous detachment (PVD) (91 cases), and B, with the absence of PVD (21 cases). Category A was divided into two subcategories: A1, without contraction of the ERM (37 cases), and A2, with the presence of membrane contraction (54 cases). A2 was further subdivided into A2.1, with retinal folding (15 ...

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    21. Inner and outer central retinal findings after surgery for rhegmatogenous retinal detachment using different spectral-domain optical coherence tomography devices

      Inner and outer central retinal findings after surgery for rhegmatogenous retinal detachment using different spectral-domain optical coherence tomography devices

      Purpose The aim of the study was to analyse macular changes after rhegmatogenous retinal detachment (RRD) repair using spectral-domain optical coherence tomography (SD-OCT). Methods Forty eyes with macula-on and 27 eyes with macula-off RRD underwent scleral buckling or vitrectomy and were postoperatively imaged using 2 SD-OCT devices (Cirrus® HD-OCT, RTVue-100®). Measurement of total and inner macular thickness consisting of ganglion cell layer + inner plexiform layer (GCL-IPL) using Cirrus or retinal nerve fibre layer + ganglion cell layer + inner plexiform layer (RNFL-GCL-IPL) using RTVue was performed. Results of inner macular thickness were compared with image results of 40 healthy controls. Qualitative analysis ...

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    22. Impact of thin-cap fibroatheroma on predicting deteriorated coronary flow during interventional procedures in acute as well as stable coronary syndromes: insights from optical coherence tomography analysis

      Impact of thin-cap fibroatheroma on predicting deteriorated coronary flow during interventional procedures in acute as well as stable coronary syndromes: insights from optical coherence tomography analysis

      The occurrence of deteriorated coronary flow associated with distal embolization during percutaneous coronary intervention results in impaired myocardial perfusion and worsens the clinical prognosis. This study aimed to examine the impact of optical coherence tomography (OCT)-determined coronary plaque morphology on the prediction of deteriorated coronary flow after stent implantation in acute as well as stable coronary syndromes (ACS and SAP, respectively). We studied 126 patients who underwent OCT during stenting for ACS ( n = 44) and SAP ( n = 82) with a de novo lesion. Angiographic deteriorated coronary flow was defined as the deterioration of TIMI flow grade after mechanical dilatation ...

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    23. Optical coherence tomography-guided selective focal laser photocoagulation: a novel laser protocol for diabetic macular edema

      Optical coherence tomography-guided selective focal laser photocoagulation: a novel laser protocol for diabetic macular edema

      Background To compare the anatomic and functional results between optical coherence tomography (OCT)-guided selective focal laser photocoagulation (OCT–laser) and conventional modified Early Treatment Diabetic Retinopathy Study (mETDRS) laser treatment for diabetic macular edema (DME). Methods We analyzed treatment outcomes in 47 consecutive eyes treated with OCT–laser compared to 31 matched eyes treated with mETDRS. In the OCT–laser group, we identified ‘significant actively-leaking microaneurysms on OCT’ (SALMO) which are responsible for edema in OCT B-scan images, and thoroughly ablated them with photocoagulation. Best-corrected visual acuity (BCVA) and retinal thickness by OCT were compared at baseline and 12 ...

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    24. Evaluation of corneal epithelial and stromal thickness in keratoconus using spectral-domain optical coherence tomography

      Evaluation of corneal epithelial and stromal thickness in keratoconus using spectral-domain optical coherence tomography

      Purpose We sought to assess the corneal thickness of the epithelium and stroma in keratoconic and normal eyes by spectral-domain optical coherence tomography (SD-OCT). Methods Fifty-seven keratoconic and 20 normal eyes were studied. The eyes were examined by SD-OCT, and the keratoconic eyes were subdivided into 2 groups: those showing only smooth corneal thinning and corneal protrusion on the image (KC1 group) and those showing abnormalities in the Bowman layer or in the stroma, or in both (KC2 group). The thicknesses at the corneal vertex and at the superior, inferior, nasal, and temporal cornea 1.5 mm from the corneal ...

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