1. Articles from iovs.org

  2. 1-24 of 432 1 2 3 4 ... 16 17 18 »
    1. Noninvasive Investigation of Deep Vascular Pathologies of Exudative Macular Diseases by High Penetration Optical Coherence Angiography

      Noninvasive Investigation of Deep Vascular Pathologies of Exudative Macular Diseases by High Penetration Optical Coherence Angiography

      Purpose: A newly developed high-penetration Doppler optical coherence angiography (HP-OCA) with a 1-μm probe beam for non-invasive investigation of vascular pathology of exudative macular diseases is introduced. A descriptive case series is presented to discuss the clinical utility of HP-OCA. Methods: Eleven eyes of 10 subjects with exudative macular disease, including 2 eyes with myopic choroidal neovascularization (mCNV), 4 eyes with age-related macular degeneration (AMD) and 5 eyes with polypoidal choroidal vasculopathy (PCV), were investigated. Two Doppler scanning modes (bi-directional and high-sensitive) of HP-OCA were used for the investigation. HP-OCA provides depth resolved and en face angiograms and a ...

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    2. Longitudinal analysis of progression in glaucoma using spectral-domain optical coherence tomography

      Longitudinal analysis of progression in glaucoma using spectral-domain optical coherence tomography

      Purpose. To compare the longitudinal loss of RNFL thickness measurements by SD-OCT in normals and glaucoma patients with or without progression concerning optic disc morphology. Methods. 62 eyes, comprising 38 glaucomatous eyes with open angle glaucoma and 24 healthy controls, were included in the study (Erlangen Glaucoma Registry, NTC00494923). All patients were investigated annually over a period of three years by Spectralis SD-OCT measuring peripapillary RNFL thickness. By masked comparative analysis of photographs the eyes were classified into non-progressive and progressive glaucoma cases. Longitudinal loss of RNFL thickness was compared to morphological changes of optic disc morphology. Results. Mixed model ...

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    3. Choroid Development and Feasibility of Choroidal Imaging in the Preterm and Term Infants Utilizing SDOCT

      Choroid Development and Feasibility of Choroidal Imaging in the Preterm and Term Infants Utilizing SDOCT

      Purpose: To determine whether choroidal imaging is feasible in preterm and term infants using an 840-nm portable spectral domain optical coherence tomography (SDOCT) system without the use of enhanced- depth imaging techniques and to assess choroidal development by comparing choroidal thickness of preterm infants, term infants, and adults. Methods: SDOCT images were obtained from 86 preterm infants, 59 term infants and 9 adults using a portable SDOCT (Bioptigen, Inc., NC, USA) system plus 9 adults using a tabletop system. An unprocessed image across the macula from one randomly selected eye of each participant was selected for determination of whether the ...

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    4. Individual A-scan Signal Normalization Between Two Spectral Domain Optical Coherence Tomography Devices

      Individual A-scan Signal Normalization Between Two Spectral Domain Optical Coherence Tomography Devices

      Purpose: To develop a method to normalize optical coherence tomography (OCT) signal profiles from two spectral-domain (SD-) OCT devices so that the comparability between devices increases. Methods: Twenty-one eyes from 14 healthy and 7 glaucoma subjects were scanned with two SD-OCT devices on the same day with equivalent cube scan patterns centered on the fovea (Cirrus HD-OCT, Carl Zeiss Meditec, Dublin, CA; and RTVue, Optovue, Fremont, CA). Foveola positions were manually selected and used as the center for registration of the corresponding images. A-scan signals were sampled 1.8 mm from the foveola in the temporal, superior, nasal and inferior ...

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    5. Longitudinal Changes in Anterior Segment Parameters after Laser Peripheral Iridotomy Assessed by Anterior Segment Optical Coherence Tomography

      Longitudinal Changes in Anterior Segment Parameters after Laser Peripheral Iridotomy Assessed by Anterior Segment Optical Coherence Tomography

      Purpose: To quantify long-term changes in anterior segment (AS) parameters after laser peripheral iridotomy (LPI) using AS optical coherence tomography (OCT) in primary angle closure suspects (PACS). Methods: Thirty two PACS subjects were imaged at pre-LPI, 2weeks and 18 months post-LPI using AS OCT. Anterior chamber depth (ACD), iris curvature (IC), iris thickness at 750 and 1500 µm from the scleral spur (IT750, 1500), lens vault (LV), anterior chamber area (AA), and iris area (IA) were estimated by image J software (version 1.46). Anterior chamber angle (ACA) parameters (angle opening distance (AOD750), angle recess area (ARA750), and trabecular iris ...

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    6. Detecting Glaucoma with Visual Fields Derived from Frequency-Domain Optical Coherence Tomography

      Detecting Glaucoma with Visual Fields Derived from Frequency-Domain Optical Coherence Tomography

      Purpose. To compare the assessment of glaucomatous damage based on visual fields (VFs) derived from frequency-domain optical coherence tomography (OCT) to actual visual fields obtained from static automated perimetry. Methods. 84 eyes from 84 glaucoma patients or suspects and 128 eyes from 128 normal subjects were included. The retinal ganglion cell (RGC) and retinal nerve fiber layer (RNFL) thicknesses measured with macular and disc RNFL cube scans were combined and decomposed into 48 principal components (PCs). For each eye, an OCT to VF transformation map was built using multiple linear regression (MLR) and the OCT and VF data from the ...

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    7. Observation of Posterior Precortical Vitreous Pocket Using Swept Source Optical Coherence Tomography

      Observation of Posterior Precortical Vitreous Pocket Using Swept Source Optical Coherence Tomography

      Purpose: To observe posterior precortical vitreous pockets (PPVPs) using swept-source optical coherence tomography (SS-OCT). Methods: We performed SS-OCT in both eyes of 58 volunteers (36 men, 22 women) using 12-mm horizontal vertical scans through the macula and optic disc. To minimize age-related changes (liquefaction or posterior vitreous detachment), all subjects were a mean of 26.2 years (range, 22-40 years). The refractive errors ranged from -9.5 diopters (D) to +3.0 D. To estimate the PPVP size, we measured the height between the fovea and the anterior border of the PPVP and the maximal width in the 12-mm horizontal ...

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      Mentions: Gunma University
    8. Correlation between the Ganglion Cell-Inner Plexiform Layer Thickness Measured with Cirrus HD-OCT and Macular Visual Field Sensitivity Measured with Microperimetry

      Correlation between the Ganglion Cell-Inner Plexiform Layer Thickness Measured with Cirrus HD-OCT and Macular Visual Field Sensitivity Measured with Microperimetry

      PURPOSE: To evaluate relationships between the macular visual field (VF) mean sensitivity and the ganglion cell and inner plexiform layer (GCA) thicknesses. METHODS: Seventy-one glaucoma patients and 29 normal subjects were included in this cross-sectional study. At each visit, GCA thicknesses were measured by Cirrus HD-OCT (Carl Zeiss Meditec, Dublin, CA) and static threshold perimetry was performed using MAIATM (Macular Integrity Assessment). The relationship between the VF sensitivity and GCA thickness was examined globally, and in the superior hemiretina, inferior hemiretina and six VF sectors with both VF and OCT in retinal view. Regression analysis was used to investigate the ...

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    9. Relationship Between the Second Reflective Band on Optical Coherence Tomography and Multifocal Electroretinography in Age-Related Macular Degeneration

      Relationship Between the Second Reflective Band on Optical Coherence Tomography and Multifocal Electroretinography in Age-Related Macular Degeneration

      Purpose: The second hyper-reflective on spectral domain optical coherence tomography (SD-OCT) has been suggested to correlate with the photoreceptor inner segment ellipsoids (ISe). The purpose of this study was to determine the relationship between the intensity of the ISe band and retinal function measured by multifocal electroretinography (mfERG) in patients with early age-related macular degeneration (AMD). Methods: A high-resolution horizontal line-scan through the fovea on SD-OCT and a mfERG recording were performed in one eye of 29 early AMD and 31 control participants. The relative intensity of the ISe band within 1000µm of the fovea was quantified using ImageJ ...

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    10. Comparison of Different Spectral Domain OCT Scanning Protocols for Diagnosing Preperimetric Glaucoma

      Comparison of Different Spectral Domain OCT Scanning Protocols for Diagnosing Preperimetric Glaucoma

      Purpose: To compare the ability of spectral-domain optical coherence tomography (SDOCT) retinal nerve fiber layer (RNFL), optic nerve head (ONH) and macular measurements to detect preperimetric glaucomatous damage. Methods: The study included 142 eyes from 91 patients suspected of having the disease based on the appearance of the optic disc. All eyes had normal visual fields before the imaging session. Forty-eight eyes with progressive glaucomatous damage were included in the preperimetric glaucoma group. Ninety-four eyes without any evidence of progressive glaucomatous damage and followed untreated for 12.8 ± 3.6 years were used as controls. Areas under the receiver operating ...

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    11. Retrobulbar Structure Visualization with Enhanced Depth Imaging Optical Coherence Tomography

      Retrobulbar Structure Visualization with Enhanced Depth Imaging Optical Coherence Tomography

      Purpose: To assess enhanced depth imaging optical coherence tomography (EDI-OCT) visualization of deep posterior pole structures and retrobulbar tissues in myopic eyes and evaluate ocular structural elements that influenced this capability. Methods: Thirty consecutive myopic eyes (>-6 diopters) from 21 patients were enrolled. Exclusion criteria included any pathological condition affecting the posterior pole. Patients underwent biometry to assess axial length, and irises were classified as darkly or lightly pigmented. EDI-OCT scans were obtained by spectral-domain OCT to image posterior pole and retrobulbar structures. Choroidal thickness was measured manually, and for eyes in which the sclera was fully visible, the thickness ...

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    12. Comparative Analysis of Repeatability of Manual and Automated Choroidal Thickness Measurements in Non-Neovascular Age-Related Macular Degeneration

      Comparative Analysis of Repeatability of Manual and Automated Choroidal Thickness Measurements in Non-Neovascular Age-Related Macular Degeneration

      Purpose: To compare the reproducibility and mutual agreement of the subfoveal choroidal thickness measurements by expert raters and an automated algorithm in enhanced depth imaging optical coherence tomography (EDI-OCT) images of eyes with non-neovascular age-related macular degeneration (AMD). Methods: Forty-four patients with non-neovascular AMD were recruited and EDI-OCT images were acquired. Subfoveal choroidal thickness was measured manually by two expert raters and automatically by a graph-cut based algorithm. Drusen area was measured using the automated software (version 6) of Cirrus SD-OCT. The manual and automated choroidal thickness measurements were compared in reproducibility, mutual agreement, and correlation with drusen area. Results ...

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    13. Repeatability and Reproducibility of Choroidal Vessel Layer Measurements in Diabetic Retinopathy using Enhanced Depth Optical Coherence Tomography

      Repeatability and Reproducibility of Choroidal Vessel Layer Measurements in Diabetic Retinopathy using Enhanced Depth Optical Coherence Tomography

      Purpose: To describe novel segmentation protocols for choroidal layers - Sattler's medium and Haller's large vessel layers, using enhanced depth imaging optical coherence tomography (EDI-OCT), and to examine the repeatability and reproducibility of these measurements in eyes with diabetic retinopathy. Methods: Fifty-one patients with Type 2 diabetes mellitus were imaged using custom EDI scanning protocols. Detailed segmentation was performed to quantify the retina, choroid, Haller's large, and Sattler's medium vessel layers in the total macular circle (TMC) and foveal central subfield (FCS). The coefficient of repeatability (CR) and intraclass correlation coefficient (ICC) were used as a measure ...

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    14. Progressive Loss of Retinal Ganglion Cell Function Precedes Structural Loss by Several Years in Glaucoma Suspects

      Progressive Loss of Retinal Ganglion Cell Function Precedes Structural Loss by Several Years in Glaucoma Suspects

      Purpose. We determined the time lag between loss of retinal ganglion cell function and retinal nerve fiber layer (RNFL) thickness. Methods. Glaucoma suspects were followed for at least four years. Patients underwent pattern electroretinography (PERG), optical coherence tomography (OCT) of the RNFL, and standard automated perimetry testing at 6-month intervals. Comparisons were made between changes in all testing modalities. To compare PERG and OCT measurements on a normalized scale, we calculated the dynamic range of PERG amplitude and RNFL thickness. The time lag between function and structure was defined as the difference in time-to-criterion loss between PERG amplitude and RNFL ...

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    15. Influence of the Eye-Tracking–Based Follow-Up Function in Retinal Nerve Fiber Layer Thickness Using Fourier-Domain Optical Coherence Tomography

      Influence of the Eye-Tracking–Based Follow-Up Function in Retinal Nerve Fiber Layer Thickness Using Fourier-Domain Optical Coherence Tomography

      Purpose. To evaluate the eye-tracking–based follow-up (EBF) function in the reproducibility of the peripapillary retinal nerve fiber layer (RNFL) thickness measurements obtained with Fourier-domain optical coherence tomography (Fd-OCT). Methods. Thirty healthy subjects were imaged on an Fd-OCT device at the same visit by two examiners. Peripapillary circular scans in “high-speed” (HS) mode with the “automatic real time” (ART) set at 16 and in “high-resolution” (HR) mode with the ART off were obtained without and with the EBF function activated. Results. Mean (±SD) global RNFL thickness was 105.1 (±9.5) μm on HS mode and 105.4 (±9.6 ...

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    16. Reproducibility of Thickness Measurements of Macular Inner Retinal Layers Using SD-OCT with or without Correction of Ocular Rotation

      Reproducibility of Thickness Measurements of Macular Inner Retinal Layers Using SD-OCT with or without Correction of Ocular Rotation

      Purpose. To evaluate the inter-visit reproducibility of spectral-domain optical coherence tomography (SD-OCT) measurement of the macular retinal nerve fiber layer thickness (mRNFLT), combined ganglion cell layer and inner plexiform layer (GCL+IPL) thickness, and ganglion cell complex (GCC) thicknesses (sum of mRNFLT and GCL+IPL thicknesses) compared with that of circumpapillary RNFLT (cpRNFLT) and the effect of ocular rotation on reproducibility. Methods. SD-OCT imaging was performed twice on different days in one eye of 58 normal subjects and 73 glaucoma patients. The reproducibility was evaluated for the entire 4.8 mm x 4.8 mm macular area and sub-areas (upper ...

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    17. Tomographic Features of Macula after Successful Macular Hole Surgery

      Tomographic Features of Macula after Successful Macular Hole Surgery

      Purpose. To determine the retinal features associated with a dissociated optic nerve fiber layer (DONFL) appearance after successful macular hole surgery with internal limiting membrane (ILM) peeling. Methods. Forty-seven eyes of 47 patients that underwent pars plana vitrectomy with ILM peeling were examined by spectral-domain optical coherence tomography (SD-OCT). Results. A DONFL appearance was found in 31 (66.0%) eyes on color fundus photography. The postoperative best-corrected visual acuity and its improvements were not significantly different between eyes with and without this appearance. The SD-OCT images showed small inner retinal defects corresponding to each arcuate stria in all eyes with ...

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    18. Comparison of Dresen Area Detected by Spectral Domain Optical Coherence Tomography and Color Fundus Imaging

      Comparison of Dresen Area Detected by Spectral Domain Optical Coherence Tomography and Color Fundus Imaging

      Purpose: To compare the measurements of drusen area from manual segmentation of color fundus photographs with those generated by an automated algorithm designed to detect elevations of the retinal pigment epithelium (RPE) on spectral domain optical coherence tomography (SDOCT) images. Methods: Fifty eyes with drusen secondary to non-exudative age-related macular degeneration (AMD) were enrolled. All eyes were imaged with the Cirrus HD-OCT instrument (Carl Zeiss Meditec, Dublin, CA) using a 200x200 A-scan raster pattern covering a 6mm X 6mm area centered on the fovea. Digital color fundus images were taken on the same day. Drusen were traced manually on the ...

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    19. Glaucoma Detection Ability of Ganglion Cell-Inner Plexiform Layer Thickness by Spectral-Domain Optical Coherence Tomography in High Myopia

      Glaucoma Detection Ability of Ganglion Cell-Inner Plexiform Layer Thickness by Spectral-Domain Optical Coherence Tomography in High Myopia

      Purpose: To compare the glaucoma detection ability of macular ganglion cell-inner plexiform layer (GCIPL) thickness measured with Cirrus spectral-domain optical coherence tomography (SD-OCT) with that of peripapillary retinal nerve fiber layer (RNFL) thickness in high myopia. Methods: In 49 highly myopic and 54 non-highly myopic glaucoma patients along with 78 healthy myopic subjects, two scans, including one macular scan and one peripapillary RNFL scan, were obtained using Cirrus SD-OCT. For 44 randomly selected glaucoma patients, three macular scans were taken for reproducibility measurements. The glaucoma detection abilities of macular GCIPL and peripapillary RNFL thicknesses were compared between the highly myopic ...

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    20. Enhancement of Lamina Cribrosa Visibility in Optical Coherence Tomography Images using Adaptive Compensation

      Enhancement of Lamina Cribrosa Visibility in Optical Coherence Tomography Images using Adaptive Compensation

      Purpose. To improve the visibility of the lamina cribrosa (LC), including its posterior boundary, in optical coherence tomography (OCT) images of the human optic nerve head (ONH). Methods. An adaptive compensation algorithm was developed to overcome a limitation of our standard compensation algorithm, that is the over-amplification of noise at high depth. Such limitation currently hampers our ability to distinguish the posterior LC boundary. In adaptive compensation, standard compensation operations are performed until an energy threshold is reached, at which stage the compensation process is stopped to limit noise over-amplification in the deeper portion of the OCT image.The performance ...

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    21. High-Resolution Images of Retinal Structure in Patients with Choroideremia

      High-Resolution Images of Retinal Structure in Patients with Choroideremia

      Purpose. To study retinal structure in choroideremia patients and carriers using high-resolution imaging techniques. Methods. Subjects from four families (six female carriers and five affected males) with choroideremia (CHM) were characterized with best-corrected visual acuity (BCVA), kinetic and static perimetry, full-field electroretinography, and fundus autofluorescence (FAF). High-resolution macular images were obtained with adaptive optics scanning laser ophthalmoscopy (AOSLO) and spectral domain optical coherence tomography (SD-OCT). Coding regions of the CHM gene were sequenced. Results. Molecular analysis of the CHM gene identified a deletion of exons 9 to 15 in family A, a splice site mutation at position 79+1 of ...

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    22. INFLUENCE OF THE EYE TRACKING-BASED FOLLOW-UP FUNCTION IN RETINAL NERVE FIBER LAYER THICKNESS USING FOURIER-DOMAIN OPTICAL COHERENCE TOMOGRAPHY

      INFLUENCE OF THE EYE TRACKING-BASED FOLLOW-UP FUNCTION IN RETINAL NERVE FIBER LAYER THICKNESS USING FOURIER-DOMAIN OPTICAL COHERENCE TOMOGRAPHY

      Purpose: To evaluate the eyetracking-based follow-up (EBF) function in the reproducibility of the peripapillary retinal nerve fiber layer (RNFL) thickness measurements obtained with Fourier-domain optical coherence tomography (Fd-OCT). Methods: Thirty healthy subjects were imaged on Fd-OCT device at the same visit by 2 examiners. Peripapillary circular scans in "high-speed" (HS) mode with the "automatic real time" (ART) set at 16 and in "high-resolution" (HR) mode with the ART off were obtained without and with the EBF function activated. Results: Mean (±SD) global RNFL thickness was 105.1 (±9.5) µm on HS mode and 105.4 (±9.6) µm on ...

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    23. Usefulness of Macular Thickness Derived from Spectral-Domain Optical Coherence Tomography (SD-OCT) in the Detection of Glaucoma Progression

      Usefulness of Macular Thickness Derived from Spectral-Domain Optical Coherence Tomography (SD-OCT) in the Detection of Glaucoma Progression

      Purpose: To assess the reproducibility of circumpapillary retinal nerve fiber layer thickness (cRNFLT) and total macular thickness (TMT) parameters using Cirrus spectral domain optical coherence tomography (SD-OCT) and to apply this information to investigate its ability to detect cases where visual field (VF) progression was noted on event-based analysis in the eyes with early glaucomatous VF loss. Methods: Intraclass correlation coefficient (ICC), coefficient of variation (COV), and intersession test-retest variability were calculated from control group. The sensitivity and specificity of SD-OCT for the identification of progressive VF defects were tested on progressive and stable patients. Results: All ICCs from cRNFLT ...

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    24. The Retinal Disease Screening Study: Prospective Comparison of Nonmydriatic Fundus Photography and Optical Coherence Tomography for Detection of Retinal Irregularities

      The Retinal Disease Screening Study: Prospective Comparison of Nonmydriatic Fundus Photography and Optical Coherence Tomography for Detection of Retinal Irregularities

      Purpose. To compare the sensitivity of volume scanning with optical coherence tomography (OCT) to nonmydriatic color fundus photography (FP) for the detection of retinal irregularities in asymptomatic populations. Methods. Asymptomatic subjects without known ocular disease were recruited over a 6-month period. For each eye, two undilated 45° fundus images and four undilated volume OCT image sets covering the macula and optic nerve were obtained. Color images were evaluated for irregularities both inside and outside the area covered by OCT. OCT image sets were evaluated for internal limiting membrane irregularities, abnormal retinal thickness, hyper/hyporeflective features, and photoreceptor/retinal pigment epithelium ...

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