1. 1-24 of 262 1 2 3 4 ... 9 10 11 »
    1. Applicability of the ISNT and IST rules on retinal nerve fiber layer measurement on spectral-domain optical coherence tomography in normal Indian children

      Applicability of the ISNT and IST rules on retinal nerve fiber layer measurement on spectral-domain optical coherence tomography in normal Indian children

      Background To determine the applicability of the ISNT (inferior>superior>nasal>temporal) and IST (inferior>superior>temporal) rules on retinal nerve fiber layer (RNFL) measurement on spectral-domain optical coherence tomography (SD-OCT) in normal children. Methods A prospective, cross-sectional study including consecutive subjects between the ages of 5–18 years who were born at term (≥37 weeks gestational age) and with a normal birth weight (≥2500 g) presenting to the out-patient department for refractive error examination. RNFL measurement was done on Spectralis SD-OCT. Exclusion criteria were best-corrected visual acuity less than 20/20, spherical equivalent (SE) > ± 5 diopter (D), applanation IOP ...

      Read Full Article
    2. Correlation between depth and area of retinal nerve fiber layer defect as measured by spectral domain optical coherence tomography

      Correlation between depth and area of retinal nerve fiber layer defect as measured by spectral domain optical coherence tomography

      Background To evaluate the correlation between the depth and area of retinal nerve fiber layer (RNFL) defect, as measured on an RNFL map of spectral-domain optical coherence tomography (SD-OCT). Methods The RNFL of 472 glaucoma subjects and of 217 healthy subjects was imaged by an SD-OCT. RNFL defect depth and area on the RNFL map were expressed as an RNFL defect depth percentage index (RDPI) and an RNFL defect area index (RDAI), respectively, according to the following two formulas: 100×[1–{summation of thicknesses of RNFL defects/summation of thicknesses of upper 95th percentile range of age-matched healthy subjects in ...

      Read Full Article
    3. Choroidal involvement in Rosai-Dorfman syndrome may be depicted and followed using enhanced depth imaging optical coherence tomography (EDI-OCT)

      Choroidal involvement in Rosai-Dorfman syndrome may be depicted and followed using enhanced depth imaging optical coherence tomography (EDI-OCT)

      Dear Editor, We read with interest the recently published case report by Vermeulen et al. [ 1 ] regarding “Rosai–Dorfman disease presenting as choroidal melanoma”. We previously published a similar presentation of a patient that underwent systemic work-up for bilateral choroidal masses [ 2 ]. Our patient initially presented with minimal visual complaints and best-corrected visual acuity of 20/20 OU. Sub-papillomacular bundle, amelanotic choroidal masses OU were discovered on dilated fundus exam. Initial work-up demonstrated focal pigment epithelial detachment OD but overall intact outer retinal layers OU on spectral domain optical coherence tomography (SD-OCT). Unlike the case report by Vermeulen et al ...

      Read Full Article
    4. Predictors of 1-year visual outcome in OCT analysis comparing ranibizumab monotherapy versus combination therapy with PDT in exsudative age-related macular degeneration

      Predictors of 1-year visual outcome in OCT analysis comparing ranibizumab monotherapy versus combination therapy with PDT in exsudative age-related macular degeneration

      Aim The aim of this study was to find predictive factors of 1-year visual outcome, analyzing novel optical coherence tomography (OCT) biomarkers in exsudative age-related macular degeneration (choroidal neovascularization (CNV)) in two groups of different treatment modalities. Methods In all, 34 consecutive patients with new-onset CNV were randomized 1:1 to receive either ranibizumab monotherapy or ranibizumab combined with photodynamic therapy (PDT) with verteporfin. After three initial injections with ranibizumab, re-treatment was performed according to an as-needed scheme; PDT was performed once at baseline. Best-corrected visual acuity (BCVA) and OCT parameters like central macular volume (CMV), central macular thickness (or ...

      Read Full Article
    5. Automated measurement of stent strut coverage in intravascular optical coherence tomography

      Automated measurement of stent strut coverage in intravascular optical coherence tomography

      Optical coherence tomography (OCT) is a non-invasive, cross-sectional imaging modality that has become a prominent imaging method in percutaneous intracoronary intervention. We present an automated detection algorithm for stent strut coordinates and coverage in OCT images. The algorithm for stent strut detection is composed of a coordinate transformation from the polar to the Cartesian domains and application of second derivative operators in the radial and the circumferential directions. Local region-based active contouring was employed to detect lumen boundaries. We applied the method to the OCT pullback images acquired from human patients in vivo to quantitatively measure stent strut coverage. The ...

      Read Full Article
    6. Precise measurement of volume of eccrine sweat gland in mental sweating by optical coherence tomography

      Precise measurement of volume of eccrine sweat gland in mental sweating by optical coherence tomography

      We have demonstrated dynamic analysis of the physiological function of eccrine sweat glands underneath skin surface by optical coherence tomography (OCT). In this paper, we propose a method for extraction of the specific eccrine sweat gland by means of the connected component extraction process and the adaptive threshold method, where the en face OCT images are constructed by the swept-source OCT. In the experiment, we demonstrate precise measurement of the volume of the sweat gland in response to the external stimulus.

      Read Full Article
    7. Quantification of fibrous cap thickness in intracoronary optical coherence tomography with a contour segmentation method based on dynamic programming

      Quantification of fibrous cap thickness in intracoronary optical coherence tomography with a contour segmentation method based on dynamic programming

      Objectives Fibrous cap thickness is the most critical component of plaque stability. Therefore, in vivo quantification of cap thickness could yield valuable information for estimating the risk of plaque rupture. In the context of preoperative planning and perioperative decision making, intracoronary optical coherence tomography imaging can provide a very detailed characterization of the arterial wall structure. However, visual interpretation of the images is laborious, subject to variability, and therefore not always sufficiently reliable for immediate decision of treatment. Methods A novel semiautomatic segmentation method to quantify coronary fibrous cap thickness in optical coherence tomography is introduced. To cope with the ...

      Read Full Article
    8. Optical coherence tomography features of angiographic complex and smooth lesions in acute coronary syndromes

      Optical coherence tomography features of angiographic complex and smooth lesions in acute coronary syndromes

      Plaque rupture (PR) and superimposed thrombosis have been shown as the most frequent underlying substrate in acute coronary syndromes (ACS). Coronary angiography is a luminogram not able to define in vivo features of the culprit plaques. The aim of the study was to use optical coherence tomography (OCT) to investigate the pathology underlying complex (CL) and non-complex angiographic lesions (NCL). We retrospectively enrolled 107 ACS patients admitted to our institution; 83 with non-ST elevation ACS (NSTE-ACS) and 24 with ST-elevation myocardial infarction. Coronary angiography was performed and culprit lesions were classified according to Ambrose criteria into NCL (n = 47) and ...

      Read Full Article
    9. Visualization of dynamic boiling processes using high-speed optical coherence tomography

      Visualization of dynamic boiling processes using high-speed optical coherence tomography

      Investigating microscale nucleate boiling processes with high heat flux requires experimental visualization and quantification with high spatial resolution in the micrometer range as well as a sufficient temporal resolution. Numerous measurement techniques are employed for providing comprehensive experimental data on microscale boiling processes and other multiphase flows. In this context, optical coherence tomography (OCT) has been introduced recently for the visualization of quasistatic growing vapor bubbles in turbid fluids with a high spatial resolution. Since OCT detects backscattered light, only one optical access is necessary and OCT is feasible for measurements in turbid media, where other imaging techniques fail. Within ...

      Read Full Article
    10. Spectral domain optical coherence tomography imaging of mucopolysaccharidoses I, II, and VI A

      Spectral domain optical coherence tomography imaging of mucopolysaccharidoses I, II, and VI A

      Purpose The purpose of this study was to describe the spectral domain optical coherence tomography (SD-OCT) characteristics of patients with retinal manifestations of mucopolysaccharidoses (MPSs) I, II, and IV A. Design The research was a prospective, observational study. Methods Fourteen consecutive patients with variants of MPS and 15 healthy subjects underwent ophthalmic assessments including fundus examinations and SD-OCT. Results The fundus examinations revealed that four patients (two MPS I and two MPS II ) had pigmented retinopathy in both eyes. In addition, one MPS II patient had cystoid macular edema and two MPS II patients had abnormal disc morphology. SD-OCT revealed ...

      Read Full Article
    11. Analysis of choroidal folds in acute Vogt–Koyanagi–Harada disease using high-penetration optical coherence tomography

      Analysis of choroidal folds in acute Vogt–Koyanagi–Harada disease using high-penetration optical coherence tomography

      Purpose To characterize patients with Vogt–Koyanagi–Harada (VKH) disease with choroidal folds (CFs) and determine how the foveal choroidal thickness changes after initial treatment using high-penetration optical coherence tomography (HP-OCT). Methods In this retrospective observational study, we analyzed 42 eyes of 21 patients with new-onset VKH disease to determine the demographic and clinical differences between patients with and without CFs. Results Twenty-four eyes (57.1 %) of 13 patients with VKH disease had CFs. The mean age ( p  = 0.0009) of patients with CFs was significantly higher than that of those without CFs (49.1 vs 39.4 years respectively ...

      Read Full Article
    12. Current and evolving uses of optical coherence tomography in the genitourinary tract

      Current and evolving uses of optical coherence tomography in the genitourinary tract

      Optical coherence tomography is an emerging imaging modality that provides high-resolution, real-time, cross-sectional visualization of urologic tissue with promising results. Early studies have demonstrated detailed, accurate histologic information of tissues sampled. Optical coherence tomography (OCT) has also been applied in evaluating malignancy of the bladder, prostate, and kidney. In the bladder, it can assist in the identification, biopsy, and intraoperative resection of lesions suspicious for bladder cancer. Intraoperative use of OCT during radical prostatectomy can improve visualization of the neurovascular bundle and surgical margins. Several small, ex vivo studies have also shown promising results in the ability of OCT to ...

      Read Full Article
    13. Fourier domain optical coherence tomography with ultralong depth range

      Fourier domain optical coherence tomography with ultralong depth range

      The depth ranges of typical implementations of Fourier domain optical coherence tomography (FDOCT), including spectral domain OCT (SDOCT) and swept source OCT (SSOCT), are limited to several millimeters. To extend the depth range of current OCT systems, two novel systems with ultralong depth range were developed in this study. One is the orthogonal dispersive SDOCT (OD-SDOCT), and the other is the recirculated swept source (R-SS) interferometer/OCT. No compromise between depth range and depth resolution is required in both systems. The developed OD-SDOCT system realized the longest depth range (over 100 mm) ever achieved by SDOCT, which is ready to ...

      Read Full Article
    14. Electroretinography and optical coherence tomography reveal abnormal post-photoreceptoral activity and altered retinal lamination in patients with enhanced S-cone syndrome

      Electroretinography and optical coherence tomography reveal abnormal post-photoreceptoral activity and altered retinal lamination in patients with enhanced S-cone syndrome

      Purpose To compare functional abnormalities of enhanced S-cone syndrome ( ESCS ), as examined using standard and extended electroretinography (ERG), with structural findings and retinal architecture obtained by spectral domain optical coherence tomography (SD-OCT). Methods Four patients with ESCS underwent standard full-field and multifocal ERGs, with extended S-cone and ON/OFF ERG protocols also performed. SD-OCT was also carried out, and longitudinal reflectivity profiles (LRPs) were calculated for the perifoveolar retina. Results All four patients exhibited pathognomonic full-field ERG findings for ESCS , with delayed responses of similar waveforms to the same intensity flash under both scotopic and photopic conditions. The amplitudes of ...

      Read Full Article
    15. The outer choroidoscleral boundary in full-thickness macular holes before and after surgery—a swept-source OCT stud

      The outer choroidoscleral boundary in full-thickness macular holes before and after surgery—a swept-source OCT stud

      Purpose To report on choroidal thickness and the morphology of the outer choroidoscleral boundary in swept-source OCT in patients with full-thickness macular holes (FTMH) before and after surgery. Methods Single center matched case–control study of 32 patients with FTMH (group 1), fellow eyes (group 2), and 32 eyes of 32 healthy controls (group 3). All eyes from group 1 had vitrectomy with a minimum follow-up of 3 months. Main outcome measures were the visibility and regularity of the outer choroidoscleral boundary (CSB), and additionally the eventual visibility of the suprachoroidal layer (SCL). Results Choroidal thickness was indifferent between groups ...

      Read Full Article
    16. Failure analysis of adhesive restorations with SEM and OCT: from marginal gaps to restoration loss

      Failure analysis of adhesive restorations with SEM and OCT: from marginal gaps to restoration loss

      Objective The objective of this study was to analyse the failure mode of adhesive interfaces by comparing OCT and scanning electron microscope (SEM) analysis of class V restoration margins located on enamel and dentin. Materials and methods Three groups were tested that differed in the application of a 3-step etch-and-rinse adhesive system (OptiBond FL) prior to cavity filling with restorative composite resin (Clearfil AP-X). After tooth restoration and polishing, the samples were loaded in a fatigue machine, and adhesive interfaces were evaluated with OCT and SEM. Results Important and complementary information could be obtained with OCT analysis in respect to ...

      Read Full Article
    17. Spectral-domain optical coherence tomographic features of choroidal neovascular membranes in multifocal choroiditis and punctate inner choroidopathy

      Spectral-domain optical coherence tomographic features of choroidal neovascular membranes in multifocal choroiditis and punctate inner choroidopathy

      Purpose To describe the spectral-domain optical coherence tomographic (SD-OCT) features of inflammatory choroidal neovascular membranes (iCNV) in multifocal choroiditis and punctate inner choroidopathy, and to compare them to those of the acute inflammatory lesions in the same underlying diseases. This is a retrospective, consecutive, observational case series. Methods Each patient underwent a comprehensive eye examination, fundus photography, and fluorescein angiography (FA) on the initial visit. SD-OCT features of iCNV were reviewed at presentation and 4 weeks later, and were compared to SD-OCT features of the inflammatory lesions. There were ten eyes with iCNV and eight eyes with the acute lesions ...

      Read Full Article
    18. Assessment of vascular response after drug-eluting stents implantation in patients with diabetes mellitus: an optical coherence tomography sub-study of the J-DESsERT

      Assessment of vascular response after drug-eluting stents implantation in patients with diabetes mellitus: an optical coherence tomography sub-study of the J-DESsERT

      Even in the drug-eluting stent era, diabetes mellitus (DM) patients have high incidences of restenosis and repeat revascularization after percutaneous coronary intervention. The aim of this study was to compare vascular response after stent implantation between sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) by using optical coherence tomography (OCT) in DM patients as well as in non-DM patients. In the Japan-Drug Eluting Stents Evaluation; a Randomized Trial (J-DESsERT), the OCT sub-study enrolled 75 patients who underwent 8 months follow-up imaging after SES or PES implantation. Mean neointimal hyperplasia (NIH) thickness was significantly thinner in SES than PES in the DM ...

      Read Full Article
    19. Structural and functional changes in glaucoma: comparing the two-flash multifocal electroretinogram to optical coherence tomography and visual field

      Structural and functional changes in glaucoma: comparing the two-flash multifocal electroretinogram to optical coherence tomography and visual field

      Purpose To correlate multifocal electroretinogram (mfERG) findings in the macular area of glaucoma patients with automated perimetry (visual fields) and with optical coherence tomography (OCT). Methods A two-global flash mfERG (VERIS™) was recorded in 20 eyes with primary open-angle glaucoma. The root mean square was calculated, and three response epochs were analysed: the direct component (15–45 ms) and two induced components (IC-1 at 45–75 ms and IC-2 at 75–105 ms). The central 10° of the mfERG was compared to the central 10° of the OCT and of the visual field. Responses grouped in a superior and in ...

      Read Full Article
    20. Comparison of neointimal coverage and extra-stent lumen between sirolimus and everolimus-eluting stent using optical coherence tomography

      Comparison of neointimal coverage and extra-stent lumen between sirolimus and everolimus-eluting stent using optical coherence tomography

      The external lumen of a stent [defined as extra-stent lumen (ESL)] assessed by optical coherence tomography (OCT) may be related to the risk of thrombus formation after sirolimus-eluting stent (SES) implantation. An everolimus-eluting stent (EES) might provide relatively minimal inflammatory reaction and appropriate neointimal coverage. The purpose of this study was to compare the neointimal thickness and ESL between SES and EES. Patients who underwent OCT examination more than 7 months after either SES or EES implantation were enrolled. Stent area (SA), lumen area (LA), neointimal area (NIA) and neointimal thickness (NIT) of each strut were measured at 1-mm intervals ...

      Read Full Article
      Mentions: Takayuki Okamura
    21. The effects of ocular magnification on Spectralis spectral domain optical coherence tomography scan length

      The effects of ocular magnification on Spectralis spectral domain optical coherence tomography scan length

      Purpose The purpose of this study was to assess the effects of incorporating individual ocular biometry measures of corneal curvature, refractive error, and axial length on scan length obtained using Spectralis spectral domain optical coherence tomography (SD-OCT). Methods Two SD-OCT scans were acquired for 50 eyes of 50 healthy participants, first using the Spectralis default keratometry (K) setting followed by incorporating individual mean-K values. Resulting scan lengths were compared to predicted scan lengths produced by image simulation software, based on individual ocular biometry measures including axial length. Results Axial length varied from 21.41 to 29.04 mm. Spectralis SD-OCT ...

      Read Full Article
    22. Optical Coherence Tomography. ESASO Course Series Vol. 4 (Textbook)

      Optical Coherence Tomography. ESASO Course Series Vol. 4 (Textbook)

      The introduction of optical coherence tomography (OCT) into routine clinical practice has massively increased the amount and diversity of information regarding the living retina, and radically changed the understanding and management of almost every retinal disease. Producing an up-to-date book on OCT amid a high technological turnover and rapidly evolving concepts is a challenging task. The authors have succeeded in their mission by selecting certain common and controversial topics rather than attempting to be all-inclusive. This softcover book with 134 pages is a compilation of 15 articles co-authored by 40 contributors forming an international panel of well-respected experts. Each chapter ...

      Read Full Article
    23. Wide-field spectral domain-optical coherence tomography in central serous chorioretinopathy

      Wide-field spectral domain-optical coherence tomography in central serous chorioretinopathy

      The aim the study was to describe wide-field spectral-domain optical coherence tomography morphologic relationships of the vitreous, retina, and choroid in central serous chorioretinopathy (CSCR) eyes. Standardized horizontal, vertical, and two oblique (supertemporal to inferonasal and supranasal to inferotemporal) SD-OCT sections were collected for 40 patient with CSCR. For extramacular imaging, images were obtained from eight locations: (1) nasal to the optic disk, (2) extreme nasal periphery, (3) superior to the superotemporal vascular arcade, (4) extreme superior periphery, (5) inferior to the inferotemporal vascular arcade, (6) extreme inferior periphery, (7) temporal to the macula, and (8) extreme temporal periphery. Wide-angle ...

      Read Full Article
    24. Advanced Endoscopic Imaging in the Upper Gastrointestinal Tract (Book)

      Advanced Endoscopic Imaging in the Upper Gastrointestinal Tract (Book)

      Advanced endoscopic imaging incorporates several methods to enhance visualization of the upper gastrointestinal tract. It is an evolving field within advanced endoscopy and particularly important for the endoscopist performing ESD, as these modalities can aid all stages of ESD. Advanced imaging involves several different techniques, from chromoendoscopy (e.g. Lugol’s solution, methylene blue, indigo carmine), to optical enhancement methods (e.g. magnified endoscopy, narrow band imaging, confocal endomicroscopy) and electronic methods (e.g. spectrometry, optical coherence tomography). Frequently, a combination of techniques is utilized to maximize visualization of the lesion and surrounding mucosa. The endoscopist performing ESD needs to ...

      Read Full Article
    1-24 of 262 1 2 3 4 ... 9 10 11 »
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks