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    1. Effect of Ophthalmic Examination Procedures on the Quality of Spectral Domain OCT Images

      Effect of Ophthalmic Examination Procedures on the Quality of Spectral Domain OCT Images
      The authors compare the image quality of spectral domain optical coherence tomography (OCT) images in eyes before and after routine ophthalmic screening procedures. The study population in this prospective case series included 24 patients (45 eyes). No significant difference in OCT scan quality factor was found in the study population pre-screening and post-screening (P > .05 for the horizontal, vertical, and raster pattern scans performed in each OCT scan series). Routine ophthalmic screening procedures do not affect the quality of spectral domain OCT images.
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    2. Quantification of Change in Axonal Birefringence Following Surgical Reduction in Intraocular Pressure

      Quantification of Change in Axonal Birefringence Following Surgical Reduction in Intraocular Pressure
      BACKGROUND AND OBJECTIVE The purpose of this study was to examine the hypothesis that retinal nerve fiber layer (RNFL) birefringence increases following surgical reduction of intraocular pressure (IOP). PATIENTS AND METHODS Twenty-six glaucomatous eyes requiring trabeculectomy or drainage implant were enrolled. Optical coherence tomography (OCT), scanning laser polarimetry (SLP), and IOP measurements were performed preoperatively and 3 months postoperatively. The OCT and SLP images were aligned using a new algorithm that aligns the vessels in an OCT image to those in the corresponding SLP reflectance image. The SLP retardance values at the location of the OCT scan circle were then ...
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    3. Visante OCT Measurement of Central Corneal Thickness Following Descemet's Stripping Endothelial Keratoplasty

      Visante OCT Measurement of Central Corneal Thickness Following Descemet's Stripping Endothelial Keratoplasty
      A 63-year-old man with Fuchs' dystrophy and cataract underwent successful phacoemulsification, insertion of a posterior chamber intraocular lens, and Descemet's stripping endothelial keratoplasty (DSEK) of the right eye. At 1-month follow-up, measurement of central corneal thickness (CCT) obtained by ultrasound pachymetry was 549 ?m. The ultrasound pachymetry measurement was thought to be an artifact, so anterior segment optical coherence tomography analysis of the right eye was performed. Both host and graft tissue were imaged in cross-section; optical coherence tomography measurement of CCT was 769 ?m. Reliable measurements of CCT are clinically important following DSEK. This case demonstrates that anterior ...
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    4. Persistent Placoid Maculopathy Imaged With Spectral Domain OCT and Autofluorescence

      Persistent Placoid Maculopathy Imaged With Spectral Domain OCT and Autofluorescence

      Persistent placoid maculopathy is a rare entity characterized by bilateral well-delineated whitish plaque-like lesions in the macula. Secondary choroidal neovascularization and extensive retinal pigment epithelial damage, highlighted by spectral domain optical coherence tomography and autofluorescence imaging, can limit visual prognosis. Aggressive immunosuppression can preserve vision and perhaps delay the onset of choroidal neovascularization.

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    5. AS-OCT as a Tool for Flap Thickness Measurement After Femtosecond-Assisted LASIK

      AS-OCT as a Tool for Flap Thickness Measurement After Femtosecond-Assisted LASIK

      BACKGROUND AND OBJECTIVE: To investigate the efficacy of anterior-segment optical coherence tomography (AS-OCT) for calculating flap thickness in femtosecond laser-assisted laser in situ keratomileusis.PATIENTS AND METHODS: Fifty-one eyes of 26 patients with myopia and myopic astigmatism were included in this prospective study. High-resolution corneal images were evaluated at 1 week and 1 month postoperatively. Images along the horizontal meridian were measured with the flap tool at seven points.RESULT: Measurements at vertex and at 1 mm nasally and temporally from the vertex were indistinct but easily defined. Although statistically not significant, flaps were found to be thinner in the ...

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    6. Optical coherence tomography findings in a case of cone-rod dystrophy

      Optical coherence tomography findings in a case of cone-rod dystrophy
      A patient with cone-rod dystrophy, who was examined thoroughly with biomicroscopy, fluorescein angiography, optical coherence tomography, and electrophysiology, is presented. Although fluorescein angiography depicted only window-defect type of hyperfluorescence, optical coherence tomography disclosed detachment of the neurosensory retina, focal absence of the outer parts of the photoreceptors' layer in the fovea, and cystoid edema in the macula. To the authors' knowledge, these findings have not been described in cone-rod dystrophy so far.
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    7. Fourier-Domain Optical Coherence Tomography Imaging of Gas Tamponade Following Macular Hole Surgery

      Fourier-Domain Optical Coherence Tomography Imaging of Gas Tamponade Following Macular Hole Surgery
      In this prospective study, the authors report fourier-domain optical coherence tomography (FD-OCT) imaging of gas-inner retinal tamponade following surgery for full-thickness macular hole and evaluate postoperative posturing based on FD-OCT findings. Patients underwent FD-OCT 1 day after pars plana vitrectomy, internal limiting membrane peel, and gas injection. Three-dimensional FD-OCT and high-resolution line scans demonstrated gas-inner retinal tamponade across the macula with the apex of tamponade located at the fovea. Inner and outer retina landmarks could be accurately identified along the curvature of the eye using FD-OCT in x-, y-, and z-planes. No pa-tients required face-down positioning postoperatively based on FD-OCT ...
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    8. Assessing the Photoreceptor Mosaic over Drusen Using Adaptive Optics and SD-OCT

      Assessing the Photoreceptor Mosaic over Drusen Using Adaptive Optics and SD-OCT

      Drusen are extracellular deposits that accumulate between the retinal pigment epithelium and Bruch’s membrane. They are one of the earliest clinical manifestations of age-related macular degeneration and it is thought that they disrupt the overlying photoreceptors, leading to subsequent vision loss. The purpose of this study was to illustrate how spectral domain optical coherence tomography and adaptive optics fundus imaging can be used to quantitatively analyze the integrity of the overlying photoreceptors in a single subject with macular drusen. This imaging approach and the image analysis metrics introduced may serve as the foundation for valuable imaging-based biomarkers for detecting ...

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    9. In Vivo Structural Characteristics of the Femtosecond LASIK-Induced Opaque Bubble Layers With Ultrahigh-Resolution SD-OCT

      In Vivo Structural Characteristics of the Femtosecond LASIK-Induced Opaque Bubble Layers With Ultrahigh-Resolution SD-OCT
      The authors report in vivo morphology of opaque bubble layers with ultrahigh-resolution anterior-segment optical coherence tomography (UHR-OCT) in 3 patients. Two patients were operated on with a 30-kHz IntraLase femtosecond laser (Abbott Medical Optics, Abbott Park, IL) and one patient was operated on with a 500-kHz VisuMax femtosecond laser (Carl Zeiss Meditec, Jena, Germany). UHR-OCT images from the patient operated on with the 500-kHz femtosecond laser revealed that the opaque bubble layer extended anterior to the flap dissection plane up to Bowman’s membrane. The lamellar flap dissection was incomplete in this patient. The opaque bubble layer in the patients ...
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    10. Spectral Domain Optical Coherence Tomography in the Diagnosis and Management of Glaucoma

      Spectral Domain Optical Coherence Tomography in the Diagnosis and Management of Glaucoma
      Spectral domain optical coherence tomography (SD-OCT) is a relatively new imaging technology that is being used for the diagnosis and management of glaucoma. This article presents a review of the specific parameters analyzed by SD-OCT and the diagnostic capability, reproducibility, and limitations of the device. SD-OCT parameters useful for diagnosis of glaucoma include retinal nerve fiber layer analysis, optic nerve head analysis, and ganglion cell complex analysis. These parameters have proven to be at least as equivalent to time-domain technology in terms of diagnostic capability and superior in terms of reproducibility. SD-OCT technology may be limited by signal quality, image ...
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    11. Measurement of Subfoveal Choroidal Thickness Using Spectral Domain Optical Coherence Tomography

      Measurement of Subfoveal Choroidal Thickness Using Spectral Domain Optical Coherence Tomography
      BACKGROUND AND OBJECTIVE To compare subfoveal choroidal thickness (SFCT) in normal patients and those with known ocular pathology using spectral domain optical coherence tomography (SD-OCT). PATIENTS AND METHODS This retrospective, observational case series was conducted at a tertiary care center where 194 consecutive eyes from 102 patients were imaged. Patients were not included or excluded based on presence or absence of pathology. One masked observer imaged the choroid and a second masked observer measured SFCT. Multivariate analysis was used and a statistical model created to analyze the changes in SFCT induced by age, diabetic retinopathy, glaucoma, wet and dry age-related ...
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    12. Quantification of Retinal Nerve Fiber Layer Thickness in Normal Eyes, Eyes With Ocular Hypertension, and Glaucomatous Eyes With SD-OCT

      Quantification of Retinal Nerve Fiber Layer Thickness in Normal Eyes, Eyes With Ocular Hypertension, and Glaucomatous Eyes With SD-OCT
      BACKGROUND AND OBJECTIVE To quantitatively evaluate and compare retinal nerve fiber layer (RNFL) thickness between normal eyes, eyes with ocular hypertension (OHT), and glaucomatous eyes in an Indian population using spectral domain optical coherence tomography (SD-OCT). PATIENTS AND METHODS Average and quadrant RNFL values were compared among three groups (66 normal eyes, 55 OHT eyes, and 51 glaucomatous eyes) and the discriminating power of each parameter was evaluated by calculating areas under receiver operator curves (AROCs). RESULTS The mean RNFL thickness was 93.45 ± 16.9 µm in glaucomatous eyes, significantly less than in normal (112.48 ± 6.8 µm ...
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    13. Direct Scanning of Pathology Specimens Using Spectral Domain Optical Coherence Tomography: A Pilot Study

      Direct Scanning of Pathology Specimens Using Spectral Domain Optical Coherence Tomography: A Pilot Study
      BACKGROUND AND OBJECTIVE Digital pathology has thus far focused on producing digital images of glass microscope slides. Spectral domain optical coherence tomography (SD-OCT) can be used to directly scan tissue blocks to produce three-dimensional histology images, potentially bypassing glass slide workflow. PATIENTS AND METHODS Formalin-fixed paraffin-embedded tissue blocks were scanned using SD-OCT and resulting images were compared with corresponding areas on microscope slides. RESULTS Low-magnification features were recognizable, including tissue outlines, fat, vessels, and outlines of colonic mucosal crypts. Subtle textures that were suggestive of benign breast lobules and ovarian tumor features were also visible. Initial SD-OCT images lacked resolution ...
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    14. Spectral Domain Optical Coherence Tomography Imaging of Dry Age-Related Macular Degeneration

      Spectral Domain Optical Coherence Tomography Imaging of Dry Age-Related Macular Degeneration

      Spectral domain optical coherence tomography is a useful new technology for imaging and measuring geographic atrophy (GA) and drusen, the hallmarks of dry age-related macular degeneration (AMD). The advantage of using this novel technique over other imaging modalities for dry AMD is that the same scan pattern can be used to image both drusen and GA while obtaining reproducible, quantitative data on both the area of GA and the morphologic features of drusen. Moreover, this strategy enables the clinician to follow the disease as it progresses from drusen to both GA and choroidal neovascularization. No other imaging modality is able ...

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    15. SD-OCT with Prolonged Scan Depth for Imaging the Anterior Segment of the Eye

      SD-OCT with Prolonged Scan Depth for Imaging the Anterior Segment of the Eye

      An 840-nm wavelength spectral domain optical coherence tomography (SD-OCT) with prolonged scan depth was developed and mounted onto a conventional slit lamp for imaging the anterior segment of the eye. X-Y cross aiming was applied to align the SD-OCT scanning position during imaging. An internal fixation target displayed on a miniature LCD monitor was provided. The SD-OCT instrument had an axial resolution of 6 µm and a prolonged scan depth of 7.2 mm. High-quality SD-OCT images, consisting of 2,048 × 2,048 pixels, were acquired of the entire anterior chamber and entire crystalline lens from a healthy subject. The ...

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    16. High-Definition Optical Coherence Tomography in a Case of Congenital Hypertrophy of the Retinal Pigment Epithelium

      High-Definition Optical Coherence Tomography in a Case of Congenital Hypertrophy of the Retinal Pigment Epithelium
      The authors describe the use of high-definition optical coherence tomography (HD-OCT) in a case of congenital hypertrophy of the retinal pigment epithelium. A 40-year-old woman presented with a large flat pigmented lesion in the inferior retinal quadrant of the left eye, which was compatible with congenital hypertrophy of the retinal pigment epithelium. The lesion was studied with HD-OCT (5 line raster and macular cube 512 × 128) and the results were compared with those of the fellow eye. The volume of the cube in the normal eye measured 7.1 mm3, whereas the volume of the cube with the lesion was ...
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    17. High-Resolution OCT Imaging of RPE Degeneration in Bilateral Diffuse Uveal Melanocytic Proliferation

      High-Resolution OCT Imaging of RPE Degeneration in Bilateral Diffuse Uveal Melanocytic Proliferation
      Bilateral diffuse uveal melanocytic proliferation is a rare paraneoplastic syndrome that presents with bilateral progressive loss of vision. A 70-year-old woman presented with a 3-month history of progressive, bilateral vision loss. The patient had bilateral, diffuse, shallow, subretinal fluid with patchy, reddish-brown lesions at the level of the retinal pigment epithelium (RPE) that showed significant early hyperfluorescence on fluorescein angiography and a corresponding loss of autofluorescence. Optical coherence tomography of both eyes revealed complete RPE and inner segment/outer segment junction loss with adjacent areas of thickening at the level of the RPE. Bilateral diffuse uveal melanocytic proliferation was diagnosed ...
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    18. Acute Severe Visual Decrease After Photodynamic Therapy With Verteporfin: Spectral-Domain OCT Features

      Acute Severe Visual Decrease After Photodynamic Therapy With Verteporfin: Spectral-Domain OCT Features

      In this report, spectral-domain optical coherence tomography (OCT) was used to characterize the acute morphologic alterations that occur when photodynamic therapy with verteporfin results in an acute severe visual decrease. The clinical and imaging records of a patient with neovascular age-related macular degeneration who suffered this complication were reviewed. Using spectral-domain OCT, two relatively distinct subretinal fluid compartments were visualized: a sparsely hyperreflective pocket of subretinal fluid overlying the fibrovascular pigment epithelial detachment, consistent with fibrinous exudation, and a more homogenously hyporeflective compartment at the periphery of the choroidal neovascular lesion, consistent with serous exudation. The higher axial resolution, and ...

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    19. Vitreopapillary Traction Diagnosed by Spectral Domain Optical Coherence Tomography

      Vitreopapillary Traction Diagnosed by Spectral Domain Optical Coherence Tomography
      This report describes a case of vitreopapillary traction with right inferior altitudinal defect similar to anterior ischemic optic neuropathy. A 35-year-old man with inferior altitudinal defect in his right eye was referred. The right optic disc was elevated and the superior disc margin was blurred. Spectral domain optical coherence tomography (SD-OCT) of the right optic disc showed the vitreous cortex was highly reflective and pulling the optic disc margin superiorly. The posterior hyaloid membrane on the nasal side of the optic disc was less reflective than that superior to the disc, suggesting that vitreopapillary traction contributed to this condition. During ...
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    20. Optical Coherence Tomography: 20 Years After

      Optical Coherence Tomography: 20 Years After
      Almost 20 years ago, in November 1991, the first description of optical coherence tomography (OCT) was published in the journal Science.1 The first clinical instrument was developed and studied at the New England Eye Center and Tufts University School of Medicine in Boston.2-7 It is conservatively estimated that more than 20,000 OCT systems are in use around the world. OCT initially revolutionized the diagnosis and treatment of macular disease, accelerated by the widespread use of intravitreally delivered drugs for the treatment of neovascular macular degeneration and diabetic macular edema. OCT-based quantitative assessment of the retinal nerve fiber ...
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    21. Benign Fleck Retinal Findings on Multifocal ERG, Microperimetry, and OCT

      Benign Fleck Retinal Findings on Multifocal ERG, Microperimetry, and OCT

      A middle-aged asymptomatic woman presented with multiple yellow-white flecks in the retinal pigment epithelium (RPE) affecting both fundi in a symmetrical pattern. The lesions were distributed around the posterior pole and midperiphery but sparing the macula, a picture similar to what was defined by Gass as benign fleck retina. Visual acuity, visual fields, full-field electroretinogram, electrooculogram, and dark adaptation were normal. Multifocal electroretinogram [0] (mfERG) was slightly subnormal in the isopters 17° to 20°. In this same area, microperimetry confirmed a mild decrease in sensitivity more patent in the upper temporal sector where some hypoautofluorescent spots were detected. Optical coherence ...

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    22. Spontaneous Deflation of an Iris Pigment Epithelial Cyst Documented With AS-OCT

      Spontaneous Deflation of an Iris Pigment Epithelial Cyst Documented With AS-OCT
      A 3-year-old girl presented with a black pupillary margin iris mass in the right eye diagnosed as an iris pigment epithelial (IPE) cyst, central (pupillary) type. The diagnosis was verified by anterior-segment optical coherence tomography (AS-OCT), which initially showed a circumscribed, round thin-walled cyst with clear lumen attached by a strand to the IPE. On follow-up 3 months later, the IPE cyst had deflated and AS-OCT showed an irregular collapsed surface with no lumen and optical shadowing. The authors report a case in which AS-OCT was used to provide information regarding the diagnosis and behavior of an IPE cyst.
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    23. Imaging Modalities for Localization of an iStent®

      Imaging Modalities for Localization of an iStent®
      The iStent (Glaukos Corporation, Laguna Hills, CA) is a 1-mm, titanium trabecular bypass stent implanted across the inner wall of Schlemm’s canal under direct gonioscopy. This study was designed to determine the best modality to identify iStent placement when gonioscopic visualization is not possible. In this in vitro study on a human cadaver eye, ultrasound biomicroscopy (UBM), anterior segment optical coherence tomography (AS-OCT), and B-scan ultrasonography were done to visualize and precisely locate two intentionally misplaced iStents. UBM could localize both intentionally misplaced stents, whereas AS-OCT could not visualize the iStent that was lodged in the sulcus. B-scan ultrasonography ...
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    1-24 of 96 1 2 3 4 »
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