1. Articles from iovs.org

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    1. Change in Drusen Area Over Time Compared Using Spectral Domain Optical Coherence Tomagraphy and Color Fundus Imaging

      Change in Drusen Area Over Time Compared Using Spectral Domain Optical Coherence Tomagraphy and Color Fundus Imaging

      Purpose: To investigate the relationship between drusen area measurements from color fundus images (CFIs) and spectral domain optical coherence tomography (SDOCT) datasets. Methods: Forty-two eyes from thirty Patients with drusen in the absence of geographic atrophy were recruited into a prospective study. Digital color fundus images and SDOCT images (CirrusTM HD-OCT) were obtained at baseline and at follow-up visits at 3 and 6 months. Registered, matched circles centered on the fovea with diameters of 3 mm and 5 mm were identified on both the CFIs and the SDOCT images. SDOCT drusen measurements were obtained using a commercially available proprietary algorithm ...

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    2. Variability and Repeatability of Quantitative, Fourier Domain-OCT Doppler Blood Flow in Young and Elderly Healthy Subjects

      Variability and Repeatability of Quantitative, Fourier Domain-OCT Doppler Blood Flow in Young and Elderly Healthy Subjects

      The purpose of this study was to determine the within-session variability and between-session repeatability of spectral Fourier-domain optical coherence tomography (Doppler FD-OCT) Doppler retinal blood flow measurements in young, and elderly subjects. Methods: Doppler FD-OCT blood flow was measured using the RTVue system (Optovue Inc., USA). One eye of each of 20 healthy young (24.7 ± 2.7 years) and 16 healthy elderly (64.6 ± 5.1 years) subjects was randomly selected and the pupil was dilated. The double circular scanning pattern of the RTVue was employed. Six Doppler FD-OCT measurements (i.e. each separate measurement comprising an upper, and ...

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    3. Anterior Segment Optical Coherence Tomography Parameters in Phacomorphic Angle Closure and Mature Cataracts

      Anterior Segment Optical Coherence Tomography Parameters in Phacomorphic Angle Closure and Mature Cataracts

      Purpose:To describe anterior segment optical coherence tomography (AS-OCT) parameters in phacomorphic angle closure (PMAC) eyes, mature cataract eyes and their fellow eyes, and identify those parameters that could be used to differentiate PMAC eyes from those with mature cataract and no PMAC. Methods:In this cross-sectional study a total of 33 PMAC subjects and 34 control patients with unilateral mature cataracts were enrolled. All patients underwent AS-OCT imaging and A-scan biometry of both eyes. Anterior chamber depth(ACD), anterior chamber area(ACA), iris thickness, iris curvature, lens vault(LV), and angle parameters including angle opening distance(AOD750) and trabecular ...

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    4. A comprehensive model for correcting RNFL readings of varying signal strengths in CIRRUS Optical Coherence Tomography (OCT)

      A comprehensive model for correcting RNFL readings of varying signal strengths in CIRRUS Optical Coherence Tomography (OCT)

      Purpose. Develop a model for the CIRRUSTM HD-OCT that allows for the comparison of retinal nerve fiber layer (RNFL) thickness measurements with dissimilar signal strengths (SS) and accounts for test-re-test variability. Methods. RNFLs were obtained in normals using the CIRRUSTM optic disc cube 200x200 protocol during a single encounter. Five RNFL scans were obtained with a SS of 9-10. Diffusion lens filters were used to degrade SS to obtain five scans at each SS group of 7-8, 5-6, and 3-4. The relationship between average RNFL thickness and SS was established and an equation was developed to allow for adjustment of ...

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    5. The cellular origins of the outer retinal bands in optical coherence tomography images

      The cellular origins of the outer retinal bands in optical coherence tomography images

      Purpose: To test the recently proposed hypothesis that the second OCT outer retinal band originates from the inner segment ellipsoid, by measuring: 1) thickness of this band within single cones, and 2) its respective distance from the external limiting membrane and outer segment tips. Methods: Adaptive optics OCT images were obtained from four normal subjects. Images were obtained at foveal (2∘) and perifoveal (5∘) locations. Cones (n = 9593) were identified and segmented in three dimensions using custom software. Features corresponding to bands 1, 2, and 3 were automatically identified. Thickness of band 2 was assessed in each cell by fitting ...

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    6. Macular measurements using spectral-domain optical coherence tomography in Chinese myopic children

      Macular measurements using spectral-domain optical coherence tomography in Chinese myopic children

      Purpose:To evaluate the macular thickness/volume in Chinese myopic children using spectral-domain optical coherence tomography (Cirrus HD-OCT; Carl Zeiss Meditec, Dublin, CA, USA) and assess its correlation with spherical equivalent refraction (SE), axial length (AL), sex and age. Methods:A total of 194 eyes from 194 children (aged 6-17 years old) with emmetropia (-0.5D<SE≤0.5D), low myopia (-3.0D<SE≤-0.5D) and moderate to high myopia (SE≤-3.0D) were recruited in the study. Each child underwent standardized ophthalmic examinations including visual acuity (VA), cycloplegic refraction and AL measurement. The macular thickness for the nine ...

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    7. Quantitative SD-OCT Imaging Biomarkers as Indicators of Age-Related Macular Degeneration Progression

      Quantitative SD-OCT Imaging Biomarkers as Indicators of Age-Related Macular Degeneration Progression

      Purpose: We developed a statistical model based on quantitative characteristics of drusen to estimate the likelihood of conversion from early and intermediate age-related macular degeneration (AMD) to its advanced exudative form (AMD progression) in the short term (less than 5 years), a crucial task to enable early intervention and improve outcomes. Methods: Image features of drusen quantifying their number, morphology, and reflectivity properties, as well as the longitudinal evolution in these characteristics, were automatically extracted from 2146 spectral domain optical coherence tomography (SD-OCT) scans of 330 AMD eyes in 244 patients collected over a period of 5 years, with 36 ...

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    8. Influence of axial length on thickness measurements using spectral domain optical coherence tomography

      Influence of axial length on thickness measurements using spectral domain optical coherence tomography

      Purpose:To assess the influence of axial length on spectral domain optical coherence tomography (SD OCT) thickness measurements in patients with subretinal visual implant. Methods:Data from eight emmetropic pseudophakic eyes of eight patients with subretinal visual implant were analyzed retrospectively. These patients participated in the monocentric part of a multicentre trial (www.clinicaltrials.gov number: NCT01024803). The axial length was measured in three short (< 22.5 mm), three medium (22.51-25.50 mm) and two long (> 25.52 mm) eyes. Using Heidelberg Spectralis, the known thickness of subretinal implant microchip (70 µm) was measured on 15 images per eye ...

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    9. Outcomes of laser peripheral iridotomy in angle closure subgroups according to anterior segment optical coherence tomography parameters

      Outcomes of laser peripheral iridotomy in angle closure subgroups according to anterior segment optical coherence tomography parameters

      Purpose: To investigate the effect of laser peripheral iridotomy (LPI) in subgroups of angle closure eyes based on anterior segment optical coherence tomography (AS OCT)-derived parameters. Methods: Angle closure (primary angle closure (PAC) or PAC glaucoma (PACG)) eyes were imaged using ASOCT before and 2 weeks after LPI. A hierarchical cluster analysis was performed using AS OCT parameters obtained before LPI, such as anterior chamber depth (ACD), anterior chamber width (ACW), iris cross-sectional area (IA), Angle opening distance and iris thickness at 750 µm from the scleral spur (AOD750 , IT750), iris curvature (IC), lens vault (LV), and anterior chamber ...

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    10. Use of Anterior Segment Optical Coherence Tomography to Predict Corneal Graft Rejection in Small Animal Models

      Use of Anterior Segment Optical Coherence Tomography to Predict Corneal Graft Rejection in Small Animal Models

      Purpose: To correlate the degree of anterior chamber (AC) inflammation and corneal thickness evaluated by anterior segment optical coherence tomography (ASOCT) with corneal graft rejection status and to explore the value of ASOCT in assisting the diagnosis or prediction of graft rejection using a rat penetrating keratoplasty (PK) model. Methods: A total of 40 PKs were performed using Fisher rats (allogeneic groups) and Lewis rats (syngeneic group) as donors and Lewis rats as recipients: isograft control group (n=10), allograft untreated group (n=10), and allograft with 1% prednisolone acetate treatment group (n=20). All the grafts were evaluated for ...

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    11. High-Resolution Imaging of Photoreceptors in Macular Microholes [Retina]

      High-Resolution Imaging of Photoreceptors in Macular Microholes [Retina]

      Purpose. To assess photoreceptor structure in macular microholes by using adaptive optics scanning laser ophthalmoscopy (AO-SLO) and spectral-domain optical coherence tomography (SD-OCT) and compare with visual acuity. Methods. Fourteen eyes from 12 patients with macular microholes underwent a full ophthalmologic examination and imaging with a fundus camera, SD-OCT, and an original prototype AO-SLO system at each visit. Results. All eyes had a cone outer segment tip line disruption and a normal retinal pigment epithelium line on SD-OCT images. Adaptive optics scanning laser ophthalmoscopy revealed foveal cone disruption (13 eyes, round or oval; 1 eye, T-shaped) in all eyes. Cone disruption ...

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    12. Repeatability of peripapillary retinal nerve fiber layer and inner retinal thickness among 2 spectral domain optical coherence tomography devices

      Repeatability of peripapillary retinal nerve fiber layer and inner retinal thickness among 2 spectral domain optical coherence tomography devices

      PURPOSE. To compare measurement of macular inner retina and peripapillary retinal nerve fiber layer (pRNFL) thickness using 2 spectral-domain optical coherence tomography (OCT) devices in glaucoma patients, patients with ocular hypertension, idiopathic and atypical Parkinson's disease and healthy controls. METHODS. One-hundred seventy-one eyes of 146 participants underwent successful pRNFL and macular scanning and automated measurement of ganglion cell layer + inner plexiform layer (GCL-IPL) using Cirrus® HD-OCT or retinal nerve fiber layer + ganglion cell layer + inner plexiform layer (RNFL-GCL-IPL) using RTVue-100®. Macular RNFL was added to the GCL-IPL thickness measured by Cirrus and was compared to the RNFL-GCL-IPL thickness of ...

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    13. In Vivo Three-Dimensional Characterization of the Healthy Human Lamina Cribrosa with Adaptive Optics Spectral-Domain Optical Coherence Tomography

      In Vivo Three-Dimensional Characterization of the Healthy Human Lamina Cribrosa with Adaptive Optics Spectral-Domain Optical Coherence Tomography

      Purpose: To characterize the in vivo 3D lamina cribrosa (LC) microarchitecture of healthy eyes using adaptive optics spectral-domain optical coherence tomography (AO-SDOCT). Methods: One randomly selected eye from each of 18 healthy subjects was scanned with Cirrus HD-OCT and AO-SDOCT centered on the optic nerve head. LC microarchitecture, imaged by the later device, was semi-automatically segmented and quantified for connective tissue volume fraction (CTVF), beam thickness, pore diameter, pore area and pore aspect ratio. The LC was assessed in central and peripheral regions of equal areas, quadrants and with depth. A linear mixed-effects model weighted by the fraction of visible ...

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    14. Retinal Regeneration Following OCT-guided Laser Injury in Zebrafish

      Retinal Regeneration Following OCT-guided Laser Injury in Zebrafish

      Purpose: Establish a focal injury/regeneration model in zebrafish using laser photocoagulation guided by optical coherence tomography (OCT). Methods: Adult zebrafish were imaged by OCT and confocal scanning laser ophthalmoscopy (cSLO) in room air through a contact lens. Using a beam combiner, 532nm laser photocoagulation was applied using the OCT C-scan image for targeting. Laser spots of 42-47mW were delivered to the retina. At multiple intervals post-injury, fish were imaged using both OCT and cSLO to follow the progression of each lesion. Histologic sections and TUNEL staining were performed to monitor the injury response. Results: Round lesions (26057 ± 621μm2 ...

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    15. Age-related Differences in Longitudinal Structural Change by Spectral Domain Optical Coherence Tomography in Early Experimental Glaucoma

      Age-related Differences in Longitudinal Structural Change by Spectral Domain Optical Coherence Tomography in Early Experimental Glaucoma

      Purpose. To characterize age-related differences in the magnitude of Spectral Domain Optical Coherence Tomography (SDOCT) structural change in early experimental glaucoma (EG). Methods. Both eyes from 4 young (1.4 - 2.6 yrs) and 4 old (18.6 - 21.9 yrs) rhesus monkeys were imaged at least 3 times at baseline, and then every 2 weeks following laser-induced, chronic, unilateral IOP elevation until the onset of EG (Confocal Scanning Laser Tomographic surface change confirmed twice). Two to 20 weeks after EG onset, animals were sacrificed and optic nerve axon counts for all eyes were performed. Masked operators delineated retinal and ...

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    16. Retinal Layer Measurements After Successful Macula-off Retinal Detachment Repair using OCT

      Retinal Layer Measurements After Successful Macula-off Retinal Detachment Repair using OCT

      Purpose: Optical coherence tomography (OCT) was used to analyze the thickness of various retinal layers of patients following successful macula-off retinal detachment (RD) repair. Methods: OCT scans of patients after successful macula-off RD repair were re-analyzed with a sub-segmentation algorithm to measure various retinal layers. Regression analysis was performed to correlate time after surgery with changes in layer thickness. In addition, patients were divided in two groups. Group 1 had a follow up period after surgery of up to 7 weeks (range 21 to 49 days). In group 2 the follow up was > 8 weeks (range 60 to 438 days ...

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    17. Prognostic value of multi-focal electroretinography and optical coherence tomography in eyes undergoing pan-retinal photocoagulation for diabetic retinopathy

      Prognostic value of multi-focal electroretinography and optical coherence tomography in eyes undergoing pan-retinal photocoagulation for diabetic retinopathy

      Purpose: To investigate the prognostic utility on visual acuity of multi-focal electroretinography (mfERG) and optical coherence tomography (OCT) in diabetic eyes receiving pan-retinal photocoagulation (PRP). Methods: Patients with severe non-proliferative diabetic retinopathy (NPDR) or early proliferative diabetic retinopathy (PDR) who needed PRP were included in this study. MfERG and OCT data were recorded before PRP, while the final best corrected visual acuity (BCVA) was recorded at 6 months following PRP. The correlation between pre-PRP data and post-PRP BCVA was analyzed using Pearson's correlation analysis and multivariate linear regression analysis. Results: Among the 42 eyes included, 31 eyes (73.8 ...

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      Mentions: Fudan University
    18. Automated volumetric analysis of interface fluid in Descemet stripping automated endothelial keratoplasty utilizing intraoperative optical coherence tomography

      Automated volumetric analysis of interface fluid in Descemet stripping automated endothelial keratoplasty utilizing intraoperative optical coherence tomography

      Purpose: To demonstrate a novel automated algorithm for segmentation of intraoperative optical coherence tomography (iOCT) imaging of fluid interface gap in Descemet stripping automated endothelial keratoplasty (DSAEK) and to evaluate the effect of intraoperative maneuvers to promote graft apposition on interface dimensions. Methods: 30 eyes of 29 patients from the anterior segment arm of the PIONEER study were included in this analysis. iOCT scans were entered into an automated algorithm which delineated the spatial extent of the fluid interface gap in three dimensions between donor and host cornea during surgery. The algorithm was validated against manual segmentation and performance was ...

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    19. Ganglion Cell-Inner Plexiform Layer Thickness of High Definition Optical Coherence Tomography in Perimetric and Preperimetric Glaucoma

      Ganglion Cell-Inner Plexiform Layer Thickness of High Definition Optical Coherence Tomography in Perimetric and Preperimetric Glaucoma

      Purpose. We determined the diagnostic performance of ganglion cell-inner plexiform layer (GCIPL) parameters of high definition optical coherence tomography (HD-OCT) in perimetric and preperimetric glaucoma, and compared it to optic nerve head (ONH) and peripapillary retinal nerve fiber layer (RNFL) parameters. Methods. In a cross-sectional study, 53 eyes of normal subjects and 83 eyes of glaucoma patients (62 perimetric and 21 preperimetric) from the Longitudinal Glaucoma Evaluation Study (LOGES) underwent HD-OCT imaging with Optic Disc and Macular Cube protocols. Diagnostic abilities of GCIPL, ONH, and RNFL parameters were determined using area under receiver operating characteristic curves (AUC) and likelihood ratios ...

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    20. Noninvasive Evaluation of Phase Retardation in Blebs after Glaucoma Surgery Using Anterior Segment Polarization-Sensitive Optical Coherence Tomography

      Noninvasive Evaluation of Phase Retardation in Blebs after Glaucoma Surgery Using Anterior Segment Polarization-Sensitive Optical Coherence Tomography

      Purpose: Evaluation of bleb morphology using anterior segment optical coherence tomography (OCT) can offer important information regarding bleb function after glaucoma surgery. However, analysis of tissue properties, such as scar fibrosis of blebs, is difficult with conventional OCT. The birefringence of the blebs as susceptible measure of fibrosis scar was evaluated using polarization-sensitive OCT (PS-OCT) and its relation with bleb function was assessed. Methods: One hundred and fifty-three blebs of 122 patients that had undergone trabeculectomy or an Ex-Press tube shunt were examined. Also, in 14 blebs of 12 patients, consecutive measurements were performed for 2 months after surgery. The ...

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    1-24 of 575 1 2 3 4 ... 22 23 24 »
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