1. Articles from tvstjournal.org

  2. 1-13 of 13
    1. A Pilot Study on Feasibility and Effectiveness of Intraoperative Spectral-Domain Optical Coherence Tomography in Glaucoma Procedures

      A Pilot Study on Feasibility and Effectiveness of Intraoperative Spectral-Domain Optical Coherence Tomography in Glaucoma Procedures

      Purpose: To demonstrate the use of a spectral-domain optical coherence tomography (SDOCT) integrated surgical microscope in glaucoma surgery. Methods: An SDOCT system was used to interface directly with an ophthalmic surgical microscope, to allow real-time intraoperative SDOCT ( i OCT) imaging during glaucoma procedures like phaco-trabeculectomy, Ahmed glaucoma valve (AGV) implantation, gonio-synechiolysis, and bleb needling. The various surgical steps during glaucoma surgeries where i OCT can be of potential help in guiding the surgeon were recorded. Results: High-resolution, cross-sectional images of the relevant structures were achieved with the i OCT system in all procedures. The surgeon could determine the depth of ...

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      Mentions: Rohit Shetty
    2. Reproducibility of Optovue RTVue Optical Coherence Tomography Retinal Thickness Measurements and Conversion to Equivalent Zeiss Stratus Metrics in Diabetic Macular Edema

      Reproducibility of Optovue RTVue Optical Coherence Tomography Retinal Thickness Measurements and Conversion to Equivalent Zeiss Stratus Metrics in Diabetic Macular Edema

      Purpose: To evaluate the reproducibility of central subfield thickness (CST) and volume measurements from optical coherence tomography (OCT) images obtained with Zeiss Stratus and Optovue RTVue, and formulate equations to convert these measurements from RTVue to ‘equivalent' Stratus values. Methods: Cross-sectional observational study from 309 eyes of 167 participants with diabetes and at least one eye with central-involved diabetic macular edema (DME; Stratus CST ≥ 250 μm) that underwent two replicate Stratus scans followed by two replicate RTVue scans centered on the fovea. Results: The Bland-Altman coefficient of repeatability for relative change in CST (the degree of change that could be ...

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    3. Direct Blood Flow Measurements in a Free RPE-Choroid Graft with Phase-Resolved Doppler OCT

      Direct Blood Flow Measurements in a Free RPE-Choroid Graft with Phase-Resolved Doppler OCT

      Purpose: We directly demonstrated the revascularization in a free retinal pigment epithelium (RPE)-choroid graft with direct blood flow detection by experimental phase-resolved Doppler optical coherence tomography (PRD-OCT). Methods: Seven patients with age-related macular degeneration underwent an RPE-choroid graft translocation in a prospective institutional cohort study. Spectral domain optical coherence tomography (SD-OCT) was used to measure the revascularization stage. With PRD-OCT the presence of flow was imaged postoperatively. Results: The PRD-OCT confirmed flow in three patients when SD-OCT indicated the afferent vessel ingrowth stage, and in all seven patients when the SD-OCT indicated the efferent vessel ingrowth stage. Conclusions: The ...

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    4. Relationship Between Optic Nerve Appearance and Retinal Nerve Fiber Layer Thickness as Explored with Spectral Domain Optical Coherence Tomography

      Relationship Between Optic Nerve Appearance and Retinal Nerve Fiber Layer Thickness as Explored with Spectral Domain Optical Coherence Tomography

      Purpose: To study the relationship between the appearance of the optic nerve and the retinal nerve fiber layer (RNFL) thickness determined by spectral domain optical coherence tomography (OCT). Methods: Records from patients with spectral domain -OCT imaging in a neuro-ophthalmology practice were reviewed. Eyes with glaucoma/glaucoma suspicion, macular/ optic nerve edema, pseudophakia, and with refractive errors > 6D were excluded. Optic nerve appearance by slit lamp biomicroscopy was related to the RNFL thickness by spectral domain -OCT and to visual field results. Results: Ninety-one patients (176 eyes; mean age: 49 ± 15 years) were included. Eighty-three eyes (47%) showed optic nerve ...

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    5. Automated 3D Segmentation of Intraretinal Surfaces in SD-OCT Volumes in Normal and Diabetic Mice

      Automated 3D Segmentation of Intraretinal Surfaces in SD-OCT Volumes in Normal and Diabetic Mice

      Purpose: To describe an adaptation of an existing graph-theoretic method (initially developed for human optical coherence tomography [ OCT ] images) for the three-dimensional ( 3D ) automated segmentation of 10 intraretinal surfaces in mice scans, and assess the accuracy of the method and the reproducibility of thickness measurements. Methods: Ten intraretinal surfaces were segmented in repeat spectral domain ( SD )- OCT volumetric images acquired from normal ( n = 8) and diabetic ( n = 10) mice . The accuracy of the method was assessed by computing the border position errors of the automated segmentation with respect to manual tracings obtained from two experts. The reproducibility was statistically assessed ...

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    6. Dual-Angle Protocol for Doppler Optical Coherence Tomography to Improve Retinal Blood Flow Measurement

      Dual-Angle Protocol for Doppler Optical Coherence Tomography to Improve Retinal Blood Flow Measurement

      Purpose: To compare the performance of two different multiple-scan protocols for total retinal blood flow (TRBF) measurement using Doppler optical coherence tomography (OCT). Methods: In the “single-angle” protocol, five Doppler scans were acquired at a single beam angle. In the “dual-angle” protocol, three scans were obtained with the OCT beam passing through the supranasal portion of the pupil and three through the infranasal portion. The data were analyzed using a custom software termed “Doppler OCT of Retinal Circulation” (DOCTORC) to generate TRBF measurements. In DOCTORC, the measurement of a vein was considered unreliable if the Doppler angle was less than ...

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    7. Comparison of a MEMS-Based Handheld OCT Scanner With a Commercial Desktop OCT System for Retinal Evaluation

      Comparison of a MEMS-Based Handheld OCT Scanner With a Commercial Desktop OCT System for Retinal Evaluation

      Purpose: The goal of this study was to evaluate the ability of our handheld optical coherence tomography (OCT) scanner to image the posterior and anterior structures of the human eye, and especially the individual layers of the retina, and to compare its diagnostic performance with that of a fixed desktop commercial ophthalmic OCT system. Methods: We compared the clinical imaging results of our handheld OCT with a leading commercial desktop ophthalmic system (RTVue) used in specialist offices. Six patients exhibiting diabetes-related retinal pathology had both eyes imaged with each OCT system. Results: In both sets of images, the structural irregularities ...

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    8. The Effect of Age on Optic Nerve Axon Counts, SDOCT Scan Quality, and Peripapillary Retinal Nerve Fiber Layer Thickness Measurements in Rhesus Monkeys

      The Effect of Age on Optic Nerve Axon Counts, SDOCT Scan Quality, and Peripapillary Retinal Nerve Fiber Layer Thickness Measurements in Rhesus Monkeys

      Purpose: To evaluate the effect of age on optic nerve axon counts, spectral-domain optical coherence tomography (SDOCT) scan quality, and peripapillary retinal nerve fiber layer thickness (RNFLT) measurements in healthy monkey eyes. Methods: In total, 83 healthy rhesus monkeys were included in this study (age range: 1.2–26.7 years). Peripapillary RNFLT was measured by SDOCT. An automated algorithm was used to count 100% of the axons and measure their cross-sectional area in postmortem optic nerve tissue samples ( N = 46). Simulation experiments were done to determine the effects of optical changes on measurements of RNFLT. An objective, fully-automated method ...

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    9. Retinal and Choroidal Imaging With 870-nm Spectral-Domain OCT Compared With 1050-nm Spectral-Domain OCT, With and Without Enhanced Depth Imaging

      Retinal and Choroidal Imaging With 870-nm Spectral-Domain OCT Compared With 1050-nm Spectral-Domain OCT, With and Without Enhanced Depth Imaging

      Purpose: The purpose of this study was to compare images of the retina and choroid obtained with Spectralis 1050-nm spectral-domain optical coherence tomography (SD-OCT) with and without enhanced depth imaging (EDI) to the commercially available 870-nm SD-OCT with and without EDI. Methods: Full-length 30° line scans were obtained with both 870- and 1050-nm Spectralis OCT instruments, with and without EDI. Two trained retina physicians masked to wavelength and EDI status assessed the ability to visualize the vitreoretinal interface and full-thickness choroid, and subfoveal choroidal thickness (SFCT) was measured. Results: Included in the study were 21 eyes. The vitreoretinal interface was ...

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    10. Optical Coherence Tomography (OCT) Device Independent Intraretinal Layer Segmentation

      Optical Coherence Tomography (OCT) Device Independent Intraretinal Layer Segmentation

      Purpose: To develop and test an algorithm to segment intraretinal layers irrespectively of the actual Optical Coherence Tomography (OCT) device used. Methods: The developed algorithm is based on the graph theory optimization. The algorithm's performance was evaluated against that of three expert graders for unsigned boundary position difference and thickness measurement of a retinal layer group in 50 and 41 B-scans, respectively. Reproducibility of the algorithm was tested in 30 C-scans of 10 healthy subjects each with the Spectralis and the Stratus OCT. Comparability between different devices was evaluated in 84 C-scans (volume or radial scans) obtained from 21 ...

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    11. Reading Center Characterization of Central Retinal Vein Occlusion Using Optical Coherence Tomography During the COPERNICUS Trial

      Reading Center Characterization of Central Retinal Vein Occlusion Using Optical Coherence Tomography During the COPERNICUS Trial

      Purpose: To determine the impact of segmentation error correction and precision of standardized grading of time domain optical coherence tomography (OCT) scans obtained during an interventional study for macular edema secondary to central retinal vein occlusion (CRVO). Methods: A reading center team of two readers and a senior reader evaluated 1199 OCT scans. Manual segmentation error correction (SEC) was performed. The frequency of SEC, resulting change in central retinal thickness after SEC, and reproducibility of SEC were quantified. Optical coherence tomography characteristics associated with the need for SECs were determined. Reading center teams graded all scans, and the reproducibility of ...

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      Mentions: Duke University
    12. A Comparison of Methods for Tracking Progression in X-Linked Retinitis Pigmentosa Using Frequency Domain OCT

      A Comparison of Methods for Tracking Progression in X-Linked Retinitis Pigmentosa Using Frequency Domain OCT

      PURPOSE: To compare the efficacy of frequency domain optical coherence tomography (fdOCT)-derived outer retinal measures in tracking disease progression in x-linked (xl) retinitis pigmentosa (RP) patients. METHODS: Macular volume scans and line scans (Spectralis) were obtained from 27 xlRP patients (15.3 ± 6.4 years) at two visits approximately 2 years apart. Changes in average outer retinal layer thicknesses across the volume scan were compared to changes detected by measures derived from the edge of the inner segment ellipsoid zone (EZ) band, that is, where the EZ band (also known as inner segment/outer segment border) disappears. Repeatability was ...

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    13. The Nature of Macular Damage in Glaucoma as Revealed by Averaging Optical Coherence Tomography Data

      The Nature of Macular Damage in Glaucoma as Revealed by Averaging Optical Coherence Tomography Data

      Purpose: To better understand the nature of glaucomatous damage, especially to the macula, the inner retinal thickness maps obtained with frequency domain optical coherence tomography (fdOCT) were averaged. Methods: Frequency domain optical coherence tomography macular and optic disc cube scans were obtained from 54 healthy eyes and 156 eyes with glaucomatous optic neuropathy. A manually corrected algorithm was used for layer segmentation. Patients' eyes were grouped both by mean deviation (MD) and hemifield classification using standard categories and 24-2 (6° grid) visual fields (VFs). To obtain average difference maps, the thickness of retinal nerve fiber (RNF) and retinal ganglion cell ...

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    1-13 of 13
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