1. 1-24 of 345 1 2 3 4 ... 13 14 15 »
    1. Use of High-Resolution Optical Coherence Tomography in the Surgical Management of Ocular Surface Squamous Neoplasia: A Pilot Study

      Use of High-Resolution Optical Coherence Tomography in the Surgical Management of Ocular Surface Squamous Neoplasia: A Pilot Study

      Purpose To evaluate whether high-resolution optical coherence tomography (HR-OCT) can detect histologic tumor margins of ocular surface squamous neoplasia (OSSN). Methods Eight eyes of 8 patients with OSSN undergoing excision were studied prospectively. Immediately before surgery, the tumor was imaged using a commercially available HR-OCT (Bioptigen/Leica Microsystems, Buffalo Grove, IL) to identify the conjunctival margins of the neoplastic lesion. The tumor borders of the lesion determined by HR-OCT were mapped in relation to an anatomical reference point and transferred intraoperatively. The tumor was excised with 4 mm margins from the visible edge of the lesion with a “no-touch” technique ...

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    2. Correlation of Outer Retinal Degeneration and Choriocapillaris Loss in Stargardt Disease Using En Face Optical Coherence Tomography and Optical Coherence Tomography Angiography

      Correlation of Outer Retinal Degeneration and Choriocapillaris Loss in Stargardt Disease Using En Face Optical Coherence Tomography and Optical Coherence Tomography Angiography

      Purpose This study measured and correlated degeneration of the junction between the inner and outer segments (IS/OS), the retinal pigment epithelium (RPE), and the choriocapillaris (CC) in Stargardt disease (STGD). Design Prospective cross-sectional study. Methods This study was conducted at the Casey Eye Institute. A total of 23 patients with STGD were enrolled and underwent optical coherence tomography angiography (OCTA). Scans were centered on the fovea. OCT slab projections and en face boundary maps were used to create masks to measure total IS/OS loss or RPE atrophy as well as regions of isolated IS/OS loss, isolated RPE ...

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    3. Anterior Segment Optical Coherence Tomography Angiography Imaging of Conjunctiva and Intrasclera in Treated Primary Open-Angle Glaucoma

      Anterior Segment Optical Coherence Tomography Angiography Imaging of Conjunctiva and Intrasclera in Treated Primary Open-Angle Glaucoma

      Purpose To investigate conjunctival and intrascleral vasculature in glaucoma eyes using anterior segment (AS)-optical coherence tomography angiography (OCTA) and assess the factors contributing to the vessel density in AS-OCTA images. Design Prospective, cross-sectional study. Methods Thirty-four patients with primary open-angle glaucoma and 20 healthy subjects were included. A swept-source OCT system was used to obtain AS-OCTA images of the corneal limbus at the nasal and temporal quadrants. Vessel densities were measured in the superficial (from the conjunctival epithelium to a depth of 200 μm) and deep (from a depth of 200 μm to 1000 μm) layers. The vessel density ...

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    4. Longitudinal Macular Structure-Function Relationships in Glaucoma and Their Sources of Variability

      Longitudinal Macular Structure-Function Relationships in Glaucoma and Their Sources of Variability

      Purpose 1) Review central structure-function (SF) relationships in glaucoma; 2) compare contributions of within-session and between-session variability to total variability of macular optical coherence tomography (OCT) thickness measurements; and 3) test the hypothesis that longitudinal within-eye variability of central SF relationships is smaller than between-individual variability. Methods We reviewed the pertinent literature on central SF relationships in glaucoma. Thirty-eight eyes (20 normal or glaucoma subjects) had ×3 macular images per session over 3 sessions and superpixels thickness measurements for ganglion cell layer (GCL), ganglion cell/inner plexiform layer (GCIPL), ganglion cell complex (GCC) and full macular thickness (FMT) were exported ...

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    5. Improved Macular Capillary Flow On Optical Coherence Tomography Angiography After Panretinal Photocoagulation For Proliferative Diabetic Retinopathy

      Improved Macular Capillary Flow On Optical Coherence Tomography Angiography After Panretinal Photocoagulation For Proliferative Diabetic Retinopathy

      Purpose To evaluate the macular microvascular changes in eyes with proliferative diabetic retinopathy (PDR) following panretinal photocoagulation (PRP) Methods Using OCT angiography, we prospectively studied 10 eyes of 10 subjects with high risk PDR immediately before, 1 month and 3-6 months following PRP, using 3x3mm OCTA scan at each visit. The following parameters were calculated for the superficial (SCP), middle (MCP), and deep capillary plexuses (DCP): parafoveal vessel density, adjusted flow index (AFI) and percent area of non-perfusion (PAN). Parafoveal SCP vessel length density (VLD) was also evaluated. We performed univariate and multivariable statistics, adjusting for age and signal strength ...

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    6. Anterior segment optical coherence tomographic angiography assessment of acute chemical injury

      Anterior segment optical coherence tomographic angiography assessment of acute chemical injury

      Purpose To compare routine clinical examination with optical coherence tomography angiography (OCTA) for the assessment of limbal conjunctival ischemia following a chemical burn. Setting Validity analysis Methods We assessed ten participants (15 eyes) with an acute chemical injury. Clinical photographs were used to determine the extent of any limbal conjunctival epithelial defect and ischemia. These were compared with the extent of limbal ischemia identified on OCTA images of the ocular surface. Quantitative and longitudinal analysis using the OCTA software were also performed. Correlations with visual outcome were sought using clinical and OCTA-derived variables. Results The extent of clinically determined limbal ...

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    7. Development of a spatial model of age-related change in the macular ganglion cell layer to predict function from structural changes

      Development of a spatial model of age-related change in the macular ganglion cell layer to predict function from structural changes

      Purpose To develop location specific models of normal, age-related changes in the macular ganglion cell layer (GCL) from optical coherence tomography (OCT). Using these OCT-derived models, we predicted visual field (VF) sensitivity and compared these results to actual VF sensitivities. Design Retrospective cohort study Methods Single eyes of 254 normal participants were retrospectively enrolled from the Centre for Eye Health (Sydney, Australia). Macular GCL measurements were obtained using Spectralis OCT. Cluster algorithms were performed to identify spatial patterns demonstrating similar age-related change. Quadratic and linear regression models were subsequently utilized to characterize age-related GCL decline. 40 participants underwent additional testing ...

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    8. Optical Coherence Tomography Angiography for Evaluation of Reperfusion following Pterygium Surgery

      Optical Coherence Tomography Angiography for Evaluation of Reperfusion following Pterygium Surgery

      Purpose To describe the use of optical coherence tomography angiography (OCTA) to quantitatively monitor the conjunctival graft revascularization after pterygium excision and conjunctival autograft (CAG) transplantation. Design Prospective, interventional case series. Methods Ten patients undergoing pterygium excision and femtosecond laser-assisted CAG transplantation were included. OCTA was performed at 1 week, 1 and 3 months postoperatively at the CAG transplantation site and harvested area. The vessel density at three different depths: conjunctival epithelium or CAG epithelium, conjunctival stroma or CAG stroma, and episclera, was evaluated and quantified. The revascularization rate was assessed and correlated with the postoperative CAG thickness. Results No ...

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    9. Impact of Binarization Thresholding and Brightness/Contrast Adjustment Methodology on Optical Coherence Tomography Angiography Image Quantification

      Impact of Binarization Thresholding and Brightness/Contrast Adjustment Methodology on Optical Coherence Tomography Angiography Image Quantification

      Purpose Binarization is a critical technique in OCTA image analysis, but there is no consistency in the method used in published OCTA studies. This study assessed whether differences in OCTA binarization and brightness/contrast adjustments affect quantification metrics. Design Prospective cross-sectional validity study Methods This was a single-center study examining 21 eyes of 11 healthy individuals. All eyes were imaged using the Carl Zeiss PLEX Elite 9000 swept source-OCTA, and quantitative metrics resulting from five binarization thresholding and five brightness/contrast adjustment methodologies were compared. All metrics were calculated for the superficial plexus and choriocapillaris (CC), as well as unaveraged ...

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    10. Association of Macular and Circumpapillary Microvasculature with Visual Field Sensitivity in Advanced Glaucoma

      Association of Macular and Circumpapillary Microvasculature with Visual Field Sensitivity in Advanced Glaucoma

      Purpose To evaluate the association between optical coherence tomography angiography (OCTA) macular and circumpapillary vessel density and visual field mean deviation (MD) in advanced primary open angle glaucoma (POAG). Design Cross-sectional study. Methods Macula (superficial layer) and optic nerve head [ONH, with (capillary density :CD) and without (vessel density: VD) automated removal of large vessels] OCTA of 34 eyes (34 patients, MD < -10 dB) were investigated as macula whole image VD (wiVD), parafoveal VD (pfVD), ONH wiVD, wiCD, circumpapillary VD (cpVD), and cpCD. Spectral domain OCT circumpapillary retinal nerve fiber layer (cpRNFL), macular ganglion cell complex (GCC) and ganglion cell ...

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    11. Optical Coherence Tomography Angiography Quantitative Assessment of Choriocapillaris Blood Flow in Central Serous Chorioretinopathy

      Optical Coherence Tomography Angiography Quantitative Assessment of Choriocapillaris Blood Flow in Central Serous Chorioretinopathy

      We would like to thank Sousa and associates for their insightful observations regarding our study. 1 We agree with their remark about the potential existence of other latent pachychoroid spectrum disorders among fellow eyes in patients with unilateral central serous chorioretinopathy (CSC). Thereby, the term “unaffected” was voluntarily chosen in our study, in contrast with the “healthy” eyes in the control group. As noted, a significant proportion of these unaffected fellow eyes could be categorized as uncomplicated pachychoroid (UCP) or pachychoroid pigment epitheliopathy (PPE), in opposition to strictly normal eyes.

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    12. The LXXV Edward Jackson Memorial Lecture: Lessons Learned from Avastin and OCT: The Great, The Good, The Bad, and The Ugly

      The LXXV Edward Jackson Memorial Lecture: Lessons Learned from Avastin and OCT: The Great, The Good, The Bad, and The Ugly

      Purpose To describe the synergistic benefits and cost-savings from the use of optical coherence tomography (OCT) and vascular endothelial growth factor (VEGF) inhibitors, particularly intravitreal bevacizumab, in the treatment of exudative age-related macular degeneration (AMD) Design Retrospective literature review and personal perspective. Methods Retrospective literature review and personal perspective. Results The introduction of the first clinically useful OCT instrument coincided with early phase clinical trials of a drug that would become known as ranibizumab. OCT provided a non-invasive imaging strategy that unambiguously showed the macular fluid associated with exudative AMD and the ability of anti-VEGF therapy to resolve this fluid ...

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    13. A Deep Learning System for Automated Angle-Closure Detection in Anterior Segment Optical Coherence Tomography Images

      A Deep Learning System for Automated Angle-Closure Detection in Anterior Segment Optical Coherence Tomography Images

      Purpose Anterior segment optical coherence tomography (AS-OCT) provides an objective imaging modality for visually identifying anterior segment structures. An automated detection system could assist ophthalmologists in interpreting AS-OCT images for presence of angle closure. Design Development of an artificial intelligence automated detection system for the presence of angle closure. Methods A deep learning system for automated angle-closure detection in AS-OCT images was developed, and this was compared with another automated angle-closure detection system based on quantitative features. A total of 4135 Visante AS-OCT images from 2113 subjects (8270 anterior chamber angle (ACA) images with 7375 open-angle and 895 angle-closure) were ...

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    14. Border Tissue Morphology is Spatially Associated with Focal Lamina Cribrosa Defect and Deep-Layer Microvasculature Dropout in Open-Angle Glaucoma

      Border Tissue Morphology is Spatially Associated with Focal Lamina Cribrosa Defect and Deep-Layer Microvasculature Dropout in Open-Angle Glaucoma

      Purpose To investigate the topographic relationship among focal lamina cribrosa (LC) defect, microvasculature dropout (MvD) and border tissue morphology in open angle glaucoma (OAG) eyes using spectral-domain (SD) optical coherence tomography (OCT) and OCT angiography. Design Cross-sectional study Methods One hundred twenty-six OAG eyes and 97 normal eyes were included. The maximum externally oblique border tissue (EOBT) length was measured by using enhanced depth imaging SD-OCT as well as focal LC defect size. Circumferential MvD width and height ratio were measured using OCT angiography. Results Significant correlations were found among the locations of focal LC defect, MvD and maximum EOBT ...

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    15. Peripapillary versus macular combined hamartoma of the retina and retinal pigment epithelium: Imaging characteristics

      Peripapillary versus macular combined hamartoma of the retina and retinal pigment epithelium: Imaging characteristics

      Purpose To compare clinical, optical coherence tomography (OCT), and fundus autofluorescence (FAF) characteristics of peripapillary versus (vs.) macular variants of combined hamartoma of the retina and retinal pigment epithelium (combined hamartoma). Design Retrospective observational, comparative case series Methods:Setting Multicentre collaborative study Study Population 50 eyes with a clinical diagnosis of combined hamartoma Observational Analysis A comparative analysis of color fundus photographs (CFPs), OCT and FAF was performed for peripapillary and macular variants of combined hamartoma. Main Outcome Measures Pigmentation and OCT features of macular and peripapillary combined hamartoma Results The review of imaging from 50 eyes of 49 patients ...

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    16. A Deep Learning Algorithm to Quantify Neuroretinal Rim Loss from Optic Disc Photographs

      A Deep Learning Algorithm to Quantify Neuroretinal Rim Loss from Optic Disc Photographs

      Purpose To train a deep learning (DL) algorithm that quantifies glaucomatous neuroretinal damage on fundus photographs using the minimum rim width relative to Bruch’s membrane opening (BMO-MRW) from spectral domain-optical coherence tomography (SDOCT). Design Cross-sectional study Methods 9,282 pairs of optic disc photographs and SDOCT optic nerve head scans from 927 eyes of 490 subjects were randomly divided into the validation plus training (80%) and test sets (20%). A DL convolutional neural network was trained to predict the SDOCT BMO-MRW global and sector values when evaluating optic disc photographs. The predictions of the DL network were compared to ...

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    17. Earliest Evidence of Preclinical Diabetic Retinopathy Revealed using OCT Angiography (OCTA) Perfused Capillary Density

      Earliest Evidence of Preclinical Diabetic Retinopathy Revealed using OCT Angiography (OCTA) Perfused Capillary Density

      Purpose To compare perfused capillary density (PCD) in diabetic patients and healthy controls using optical coherence tomography angiography (OCTA). Methods Forty controls, 36 diabetics without clinical retinopathy (NoDR), 38 with nonproliferative retinopathy (NPDR), and 38 with proliferative retinopathy (PDR) were imaged using SD-OCT. A 3x3 mm full-thickness parafoveal OCTA scan was obtained from each participant. Following manual delineation of the foveal avascular zone (FAZ), FAZ area, perimeter, and acircularity index were determined. Seven consecutive equidistant 200-μm-wide annular segments were drawn at increasing eccentricities from the FAZ margin. Annular PCD (%) was defined as perfused capillary area divided by the corresponding ...

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    18. Macular colobomata: Comparison of clinical and optical coherence tomography features with serological results

      Macular colobomata: Comparison of clinical and optical coherence tomography features with serological results

      Purpose To assess the correlation between the morphological features and serology in eyes with macular colobomata (MC). Design Retrospective comparative case series Methods Setting: Institutional Study population Patients presenting with MC to the retina clinic over a period of two years (January 2016 to December 2017) Interventional/Observational procedure: Color fundus and swept source optical coherence tomography (SS-OCT, Topcon Inc.) features were reviewed and assessed in three groups based on the serum IgG results: positive for Toxoplasma, positive for Cytomegalovirus (CMV), and serology negative. Main outcome measure Morphological features on clinical and OCT-based examination Results A total of 49 eyes ...

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    19. Age-Dependent Changes in the Macular Choriocapillaris of Normal Eyes Imaged with Swept-Source OCT Angiography

      Age-Dependent Changes in the Macular Choriocapillaris of Normal Eyes Imaged with Swept-Source OCT Angiography

      Purpose Swept source optical coherence tomography angiography (SS-OCTA) was used to measure the age-dependent changes in macular choriocapillaris (CC) flow deficits (FDs) in normal eyes. Design A prospective, cross-sectional study. Methods Subjects with normal eyes ranging in age from their 20s to their 80s were imaged using a 100-kHz SS-OCTA instrument (PLEX ® Elite 9000, Carl Zeiss Meditec). Both 3x3 mm and 6x6 mm scans were used to image the macular CC. Visualization of the CC and quantification of FDs were performed using a previously validated algorithm. The percentage of FDs (FD%) in the central 1 mm circle (C 1 ), 1 ...

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    20. Looking Back: Fluorescein Angiography And Optical Coherence Tomography And The First Century Of The American Journal Of Ophthalmology

      Looking Back: Fluorescein Angiography And Optical Coherence Tomography And The First Century Of The American Journal Of Ophthalmology

      This perspective follows an earlier article by Feibel (1) which reviewed the development of ophthalmic photography as seen in the first one hundred years of the American Journal of Ophthalmology (hereafter: the Journal). Here I will review fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) as presented to the readers of the Journal over the last one hundred years. As in Feibel’s review no effort has been made to analyze every article nor is there any claim to this being a complete history of FFA and OCT.

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    21. Advanced Optical Coherence Tomography Angiography Analysis of Age-related Macular Degeneration Complicated by Onset of Unilateral Choroidal Neovascularization

      Advanced Optical Coherence Tomography Angiography Analysis of Age-related Macular Degeneration Complicated by Onset of Unilateral Choroidal Neovascularization

      I read the article by Arrigo and associates 1 on optical coherence tomography angiography (OCTA) analysis of retinal vasculature in cases of unilateral choroidal neovascularization (CNV) using quantitative analytical techniques with great interest. However, I have few concerns.

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    22. Vitrectomy for diabetic macular edema: optical coherence tomography criteria and pathology of the vitreomacular interface

      Vitrectomy for diabetic macular edema: optical coherence tomography criteria and pathology of the vitreomacular interface

      Purpose To correlate spectral-domain optical coherence tomography (SD-OCT) criteria and clinical data with pathology of the vitreomacular interface (VMI) in eyes with diabetic macular edema (DME). Design Retrospective cross-sectional study and laboratory investigation. Methods We included specimens of 27 eyes of 26 patients with center-involved DME that underwent vitrectomy with peeling of the internal limiting membrane (ILM). Selection of specimens was consecutive and in retrospect using our register of the Vitreoretinal Pathology Unit. Clinical data and SD-OCT examinations were correlated to immunocytochemistry and transmission electron microscopy. Classification of DME comprised sponge-like diffuse retinal thickening, cystoid macular edema, and serous retinal ...

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    23. Automated Detection of the Stromal Demarcation Line using Optical Coherence Tomography in Keratoconus Eyes after Corneal Crosslinking

      Automated Detection of the Stromal Demarcation Line using Optical Coherence Tomography in Keratoconus Eyes after Corneal Crosslinking

      Purpose To evaluate the role of a novel automated detection software as compared to human operators in assessing the presence and depth of stromal demarcation line on optical coherence tomography (OCT) in keratoconus eyes post cross-linking Design: This was a reliability analysis study. Methods Two independent operators and an automated detection software examined corneal OCTs of 25 eyes of 25 patients post corneal cross-linking using the Dresden protocol, at 3 months postoperatively. Operators evaluated the presence of the demarcation line and measured its depth by looking at OCT images (128 cuts) on two separate occasions one week apart. The automated ...

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