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    1. Plateau Iris Distribution Across Anterior Segment Optical Coherence Tomography Defined Subgroups of Subjects With Primary Angle Closure Glaucoma

      Plateau Iris Distribution Across Anterior Segment Optical Coherence Tomography Defined Subgroups of Subjects With Primary Angle Closure Glaucoma

      Purpose : We previously identified three distinct subgroups of patients with primary angle closure glaucoma (PACG) based on anterior segment optical coherence tomography (ASOCT) imaging. Group 1 was characterized by a large iris area with deepest anterior chambers, group 2 by a large lens vault (LV) and shallow anterior chamber depth (ACD), and group 3 displayed intermediate values across iris area, LV, and ACD. The purpose of the present study was to determine the distribution of plateau iris in these subgroups using ultrasound biomicroscopy (UBM) features. Methods : UBM images of the 210 subjects who were previously enrolled for the ASOCT subgrouping ...

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    2. Correlation Between Macular Integrity Assessment and Optical Coherence Tomography Imaging of Ellipsoid Zone in Macular Telangiectasia Type 2

      Correlation Between Macular Integrity Assessment and Optical Coherence Tomography Imaging of Ellipsoid Zone in Macular Telangiectasia Type 2

      Purpose : To correlate ellipsoid zone (EZ) defects on spectral-domain optical coherence tomography (SD-OCT) with retinal sensitivity loss on macular integrity assessment (MAIA) microperimetry in macular telangiectasia type 2 (MacTel). Methods : Macular SD-OCT volumes and microperimetry maps were obtained during the international, multicenter, randomized phase 2 trial of ciliary neurotrophic factor for type 2 MacTel on two visits within 5 days of one another. Software was developed to register SD-OCT to MAIA scanning laser ophthalmoscopy images and to overlay EZ defect areas on the microperimetry maps generated from microperimetry sensitivity values at specific points and from interpolated sensitivity values. A total ...

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    3. Optical Coherence Tomography Angiography Reveals Spatial Bias of Macular Capillary Dropout in Diabetic Retinopathy

      Optical Coherence Tomography Angiography Reveals Spatial Bias of Macular Capillary Dropout in Diabetic Retinopathy

      Purpose : Our purpose is to evaluate the spatial bias of macular capillary dropout accompanying diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA). Methods : This study included 47 patients with diabetes and 29 healthy individuals who underwent OCTA. Retinal capillary flow density (FD) of 2.6 × 2.6 or 5.2 × 5.2 mm foveal area as well as the four divided areas (superior, inferior, temporal, nasal) without a foveal avascular zone (FAZ) at the superficial capillary plexus and deep capillary plexus (DCP) were measured respectively using ImageJ and NI Vision. Spatial biases of FD (orientation bias ratio and hierarchical ...

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    4. Validation of optical coherence tomography retinal segmentation algorithm in neuro-degenerative disease

      Validation of optical coherence tomography retinal segmentation algorithm in neuro-degenerative disease

      Purpose : This study compared the automated retinal segmentation software of spectral domain optical coherence tomography (SD-OCT) with manually corrected segmentation in order to guide and validate its use in a prospective clinical study of neuro-degenerative diseases (NDD). Methods : The sample comprised 30 NDD patients, including individuals with vascular cognitive impairment (n=13), frontotemporal dementia (n=6), Parkinson's disease (n=6) and Alzheimer's disease (n=5). Retinal SD-OCT scans were acquired for both eyes and then segmented using the Heidelberg Spectralis (Heidelberg, Germany) software (version 6.3.4.0). All SD-OCT scans had a quality score of 20 or ...

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    5. Mapping Retinal and Choroidal Thickness in Unilateral Nongranulomatous Acute Anterior Uveitis Using Three-Dimensional 1060-nm Optical Coherence Tomography

      Mapping Retinal and Choroidal Thickness in Unilateral Nongranulomatous Acute Anterior Uveitis Using Three-Dimensional 1060-nm Optical Coherence Tomography

      Purpose : To analyze retinal thickness (RT) and choroidal thickness (ChT) changes in patients with unilateral nongranulomatous acute anterior uveitis (AAU) using three-dimensional (3D) 1060-nm optical coherence tomography (OCT). Methods : Retinal and choroidal thickness maps were statistically analyzed for 24 patients with newly diagnosed unilateral AAU before therapy. A total of 17 patients were followed until resolution of inflammatory activity (twice in the first week, then weekly). Resolution occurred in all subjects within 6 weeks after the initial diagnosis. After resolution, thickness maps were again generated. All patients were imaged by high-speed spectral-domain (SD) 3D 1060-nm OCT over a 10 × 10-mm ...

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    6. Photoreceptor Layer Thickness Changes During Dark Adaptation Observed With Ultrahigh-Resolution Optical Coherence Tomography

      Photoreceptor Layer Thickness Changes During Dark Adaptation Observed With Ultrahigh-Resolution Optical Coherence Tomography

      Purpose : To examine outer retinal band changes after flash stimulus and subsequent dark adaptation with ultrahigh-resolution optical coherence tomography (UHR-OCT). Methods : Five dark-adapted left eyes of five normal subjects were imaged with 3-μm axial-resolution UHR-OCT during 30 minutes of dark adaptation following 96%, 54%, 23%, and 0% full-field and 54% half-field rhodopsin bleach. We identified the ellipsoid zone inner segment/outer segment (EZ[IS/OS]), cone interdigitation zone (CIZ), rod interdigitation zone (RIZ), retinal pigment epithelium (RPE), and Bruch's membrane (BM) axial positions and generated two-dimensional thickness maps of the EZ(IS/OS) to the four bands. The ...

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    7. Cell Motility as Contrast Agent in Retinal Explant Imaging With Full-Field Optical Coherence Tomography

      Cell Motility as Contrast Agent in Retinal Explant Imaging With Full-Field Optical Coherence Tomography

      Purpose : To use cell motility as a contrast agent in retinal explants. Methods : Macaque and mouse retinal explants were imaged with high resolution full field optical coherence tomography (FFOCT) and dynamic FFOCT, coupled with fluorescence imaging. Results : Static and dynamic FFOCT create complementary contrast from different structures within a cell. When imaging in vitro samples, static FFOCT detects steep refractive index gradients to reveal stationary structures including fibers, vessels, collagen, and cell contours, while dynamic FFOCT emphasizes metabolic activity of moving structures that are mainly intracellular, thus creating or enhancing contrast in cells that were previously hidden in noise. Dynamic ...

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    8. The Properties of Outer Retinal Band Three Investigated With Adaptive-Optics Optical Coherence Tomography

      The Properties of Outer Retinal Band Three Investigated With Adaptive-Optics Optical Coherence Tomography

      Purpose : Optical coherence tomography's (OCT) third outer retinal band has been attributed to the zone of interdigitation between RPE cells and cone outer segments. The purpose of this paper is to investigate the structure of this band with adaptive optics (AO)-OCT. Methods : Using AO-OCT, images were obtained from two subjects. Axial structure was characterized by measuring band 3 thickness and separation between bands 2 and 3 in segmented cones. Lateral structure was characterized by correlation of band 3 with band 2 and comparison of their power spectra. Band thickness and separation were also measured in a clinical OCT ...

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    9. Optical Coherence Tomography Analysis Based Prediction of Humphrey 24-2 Visual Field Thresholds in Patients With Glaucoma

      Optical Coherence Tomography Analysis Based Prediction of Humphrey 24-2 Visual Field Thresholds in Patients With Glaucoma

      Purpose : A pilot study showed that prediction of individual Humphrey 24-2 visual field (HVF 24-2) sensitivity thresholds from optical coherence tomography (OCT) image analysis is possible. We evaluate performance of an improved approach as well as 3 other predictive algorithms on a new, fully independent set of glaucoma subjects. Methods : Subjects underwent HVF 24-2 and 9-field OCT (Heidelberg Spectralis) testing. Nerve fiber (NFL), and ganglion cell and inner plexiform (GCL+IPL) layers were cosegmented and partitioned into 52 sectors matching HVF 24-2 test locations. The Wilcoxon rank sum test was applied to test correlation R , root mean square error (RMSE ...

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    10. Optical Coherence Tomography Angiography of the Superficial Microvasculature in the Macular and Peripapillary Areas in Glaucomatous and Healthy Eyes

      Optical Coherence Tomography Angiography of the Superficial Microvasculature in the Macular and Peripapillary Areas in Glaucomatous and Healthy Eyes

      Purpose : To quantitatively evaluate the superficial microvasculature in the macular and peripapillary areas in glaucomatous and healthy eyes using optical coherence tomography angiography (OCT-A). Methods : We enrolled 26 eyes of medically managed primary open-angle glaucoma patients and 27 eyes of healthy subjects were enrolled in this prospective study. Measurements of OCT-A vessel density were acquired both in the macular and peripapillary areas. We compared vessel density values, the circumpapillary retinal nerve fiber layer (cpRNFL), the ganglion cell complex (GCC), and standard automated perimetry (SAP) parameters across study groups. Areas under the receiver operating characteristic (AUROC) curves were used to evaluate ...

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    11. Posterior Staphylomas in Pathologic Myopia Imaged by Widefield Optical Coherence Tomography

      Posterior Staphylomas in Pathologic Myopia Imaged by Widefield Optical Coherence Tomography

      Purpose : To examine posterior staphylomas by widefield optical coherence tomography (WF-OCT) and three-dimensional magnetic resonance imaging (3D-MRI). Methods : Highly myopic patients (myopic refractive error >8.0 diopters or axial length >26.5 mm) who had previously undergone orbital 3D-MRI were examined by WF-OCT. Results : The study included 100 eyes of 57 patients with a mean age of 67.9 ± 10.7 years (range, 44–85 years) and mean axial length of 30.0 ± 2.3 mm (range, 25.1–36.5 mm). All staphylomas detected on the 3D-MRI, except for two very large staphylomas, were visualized on the WF-OCT images ...

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    12. Indocyanine Green Angiography and Optical Coherence Tomography Angiography of Choroidal Neovascularization in Age-Related Macular Degeneration

      Indocyanine Green Angiography and Optical Coherence Tomography Angiography of Choroidal Neovascularization in Age-Related Macular Degeneration

      Purpose : To compare the capability of indocyanine green angiography (ICGA) and optical coherence tomography angiography (OCTA) in detecting choroidal neovascularization (CNV). Methods : In this prospective study, patients with CNV detected with fluorescein angiography (FA) underwent ICGA and OCTA, spectral domain OCT (SD-OCT), and infrared or fundus color photographs. CNV lesions were outlined on ICGA and OCTA images, and the composition and size of the CNV was documented. Results : One hundred eighty-two eyes were included. With ICGA, well-defined lesions were observed in 37.9%, partly defined in 44.5%, and undefined in 17% of eyes. On OCTA, well-defined, partly defined, and ...

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    13. Reduced Retinal Vessel Density in Obstructive Sleep Apnea Syndrome Patients: An Optical Coherence Tomography Angiography Study

      Reduced Retinal Vessel Density in Obstructive Sleep Apnea Syndrome Patients: An Optical Coherence Tomography Angiography Study

      Purpose : To examine the retinal vasculature in patients with obstructive sleep apnea–hypopnea syndrome (OSAS) and to determine the correlation between retinal vascularity and the severity of OSAS. Design : Prospective, cross-sectional study. Methods : Sixty-nine consecutive subjects who underwent polysomnography were enrolled. Patients were divided into three groups according to the severity of OSAS, which was defined using the apnea-hypopnea index (AHI) as normal-to-mild (AHI <15), moderate (≥15 to <30), or severe (≥30). The vessel densities, and macular and retinal nerve fiber layer thicknesses were compared among the three groups. The correlations between clinical variables (age, heart rate, body mass index ...

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    14. Optical Coherence Tomography Features Preceding the Onset of Advanced Age-Related Macular Degeneration

      Optical Coherence Tomography Features Preceding the Onset of Advanced Age-Related Macular Degeneration

      Purpose : Age-related macular degeneration (AMD) is a progressive disease with multifactorial etiology. There is a need to identify clinical features that are harbingers of advanced disease. We evaluated morphologic features of the retina and choroid on optical coherence tomography (OCT) to determine if they predict progression to advanced disease. Methods : Progressors transitioned from early or intermediate AMD to advanced disease ( n = 40 eyes), and were matched on baseline AMD grade and follow-up interval to nonprogressors who did not develop advanced AMD ( n = 40 eyes). Features of the neurosensory retina, photoreceptors, retinal pigment epithelium (RPE), and choroid were evaluated. Logistic regression ...

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    15. Optical Coherence Tomographic Imaging of Posterior Episclera and Tenon's Capsule

      Optical Coherence Tomographic Imaging of Posterior Episclera and Tenon's Capsule

      Purpose : To investigate structural features of the posterior episclera and Tenon's capsule in patients with high myopia. Methods : This hospital-based observational study included highly myopic eyes (myopic refractive error > −8 diopters or axial length ≥26.5 mm) in which the posterior sclera in its full thickness could be visualized on swept-source optical coherence tomography (OCT) images in all 12 radial scans centered on the fovea. We assessed the posterior episclera and Tenon's capsule. Results : The study included 278 eyes of 175 patients (mean age, 60.9 ± 11.4 years; range, 32–89 years; axial length, 30.7 ± 1 ...

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    16. Author Response: Biomechanical Responses of Lamina Cribrosa to Intraocular Pressure Change Assessed by Optical Coherence Tomography in Glaucoma Eyes

      Author Response: Biomechanical Responses of Lamina Cribrosa to Intraocular Pressure Change Assessed by Optical Coherence Tomography in Glaucoma Eyes

      Our recent publication 1 noted several features of change in anterior lamina depth (ALD) with change in intraocular pressure (IOP) in glaucoma patients. ALD changed more in the lower ranges of IOP than at higher ranges, which represents the expected increased stiffening of biomaterials in regions of higher stress. Some eyes exhibited movement of the lamina out of the eye at lower IOP—a behavior that is more likely when the peripapillary sclera is more compliant. This was more common in eyes with less glaucoma damage. The regions of the lamina that moved more were in its vertical poles, above ...

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    17. Biomechanical Responses of Lamina Cribrosa to Intraocular Pressure Change Assessed by Optical Coherence Tomography in Glaucoma Eyes

      Biomechanical Responses of Lamina Cribrosa to Intraocular Pressure Change Assessed by Optical Coherence Tomography in Glaucoma Eyes

      We read with great interest the paper by Quigley et al. 1 investigating the change in anterior lamina cribrosa depth (LCD) before and after several intraocular pressure (IOP)-lowering procedures. They found that the LC can move either anteriorly or posteriorly with IOP decrease, and this change was greater with lower IOP. Quantitative assessment of LCD depends on the reference plane from which the measurements are made, and it is significantly influenced by choroidal thickness (CT) when a Bruch's membrane opening (BMO) reference plane is used. 2 , 3 In the study by Quigley et al., 1 the anterior LCD ...

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    18. Structural Changes in Optical Coherence Tomography Underlying Spots of Increased Autofluorescence in the Perilesional Zone of Geographic Atrophy

      Structural Changes in Optical Coherence Tomography Underlying Spots of Increased Autofluorescence in the Perilesional Zone of Geographic Atrophy

      Purpose : To investigate structural correlates corresponding to the appearance of increased fundus autofluorescence (FAF) in the perilesional area of geographic atrophy (GA) secondary to age-related macular degeneration. Methods : Serial FAF images of 181 eyes with GA of 134 patients participating in the Directional Spread in Geographic Atrophy study (NCT02051998) were screened for increased FAF spots that had developed during the review period. Thickness and reflectivity of the retinal pigment epithelium (RPE)–basal lamina complex, as well as the integrity of the external limiting membrane (ELM) and the ellipsoid zone (EZ), respectively, in corresponding optical coherence tomography (OCT) scans were compared ...

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    19. Axial Length Variation Impacts on Superficial Retinal Vessel Density and Foveal Avascular Zone Area Measurements Using Optical Coherence Tomography Angiography

      Axial Length Variation Impacts on Superficial Retinal Vessel Density and Foveal Avascular Zone Area Measurements Using Optical Coherence Tomography Angiography

      Purpose : To evaluate the impact of image magnification correction on superficial retinal vessel density (SRVD) and foveal avascular zone area (FAZA) measurements using optical coherence tomography angiography (OCTA). Methods : Participants with healthy retinas were recruited for ocular biometry, refraction, and RTVue XR Avanti OCTA imaging with the 3 × 3-mm protocol. The foveal and parafoveal SRVD and FAZA were quantified with custom software before and after correction for magnification error using the Littman and the modified Bennett formulae. Relative changes between corrected and uncorrected SRVD and FAZA were calculated. Results : Forty subjects were enrolled and the median (range) age of the ...

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    20. Author Response: Gap in Capillary Perfusion on Optical Coherence Tomography Angiograph

      Author Response: Gap in Capillary Perfusion on Optical Coherence Tomography Angiograph

      We appreciate the valuable comments from Huang and Sha 1 regarding our recent article. 2 Their comments raise an important point about image artifacts in optical coherence tomography angiography (OCTA). Image artifacts in OCTA are common and physicians should be aware of this problem. 3 As reported elsewhere, it is difficult to evaluate precise vascular abnormalities when macular edema is present. 4 Thus, in the current study, we described our OCTA protocol in cases in which macular edema persisted. 2 In eyes with persistent macular edema, OCTA was performed within 2 months after the last anti-VEGF treatment, when the macular ...

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    21. Gap in Capillary Perfusion on Optical Coherence Tomography Angiography

      Gap in Capillary Perfusion on Optical Coherence Tomography Angiography

      We read with great interest the recent article by Tsuboi et al.1 The authors used optical coherence tomography angiography (OCTA) and a threshold technique to evaluate correlations between persistent macular edema associated with branch retinal vein occlusion (BRVO), and the macular perfusion status in the superficial (SCP) and deep (DCP) capillary plexus. They found that the gap between the SCP and DCP (i.e., specifically the presence of isolated vessels in the SCP existing simultaneously with capillary loss in the DCP) was associated with persistent macular edema. We congratulate the authors for their excellent work and would like to ...

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    22. The Impact of Lens Opacity on SD-OCT Retinal Nerve Fiber Layer and Bruch's Membrane Opening Measurements Using the Anatomical Positioning System (APS)

      The Impact of Lens Opacity on SD-OCT Retinal Nerve Fiber Layer and Bruch's Membrane Opening Measurements Using the Anatomical Positioning System (APS)

      Purpose : To evaluate the impact of lens opacity on retinal nerve fiber layer thickness (RNFLT) and Bruch's membrane opening (BMO) measurements. Methods : Fifty-nine randomly selected patients without any other relevant ocular pathology undergoing elective routine cataract surgery in two specialized eye clinics were enrolled. RNFLT, BMO area, and BMO minimum rim width (BMO-MRW) were assessed with the Heidelberg Engineering Spectralis OCT using the anatomical positioning system (APS) prior to and 1 day after cataract surgery using a ring scan at different eccentricities of the disc (3.5, 4.1 and 4.7 mm). Lens opacity was quantified using densitometry ...

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    23. Repeatability and Reproducibility of Retinal Blood Flow Measurement Using a Doppler Optical Coherence Tomography Flowmeter in Healthy Subjects

      Repeatability and Reproducibility of Retinal Blood Flow Measurement Using a Doppler Optical Coherence Tomography Flowmeter in Healthy Subjects

      Purpose : To evaluate the repeatability and reproducibility of retinal blood flow (RBF) measurements in humans by using new auto-alignment and measurement software in a commercially available Doppler optical coherence tomography (DOCT) system. Methods : The DOCT flowmeter assessed the intrasession repeatability and the intersession and interobserver reproducibility of the RBF measurements. For intrasession repeatability, the coefficients of variation (CVs) of five repeated RBF measurements were calculated at the retinal arteries and veins in 20 normal eyes of 20 healthy volunteers. For intersession reproducibility, two sets of three measurements obtained by one observer on 2 different days were compared. For interobserver reproducibility ...

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    24. Biomechanical Responses of Lamina Cribrosa to Intraocular Pressure Change Assessed by Optical Coherence Tomography in Glaucoma Eyes

      Biomechanical Responses of Lamina Cribrosa to Intraocular Pressure Change Assessed by Optical Coherence Tomography in Glaucoma Eyes

      Purpose : The purpose of this study was to measure change in anterior lamina cribrosa depth (ALD) globally and regionally in glaucoma eyes at different intraocular pressures (IOP). Methods : Twenty-seven glaucoma patients were imaged before and after IOP-lowering procedures using optical coherence tomography. The anterior lamina was marked in approximately 25 locations in each of six radial scans to obtain global and regional estimates of ALD. ALD and its change with IOP were compared with optic disc damage, nerve fiber layer thickness, and visual field loss. Results : Variables associated with deeper baseline ALD included larger cup/disc ratio, thinner rim area ...

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    1-24 of 197 1 2 3 4 5 6 7 8 9 »
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