1. Masanori Hangai

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    1. Mentioned In 51 Articles

    2. Analysis of Fundus Shape in Highly Myopic Eyes by Using Curvature Maps Constructed from Optical Coherence Tomography

      Analysis of Fundus Shape in Highly Myopic Eyes by Using Curvature Maps Constructed from Optical Coherence Tomography

      Purpose To evaluate fundus shape in highly myopic eyes using color maps created through optical coherence tomography (OCT) image analysis. Methods We retrospectively evaluated 182 highly myopic eyes from 113 patients. After obtaining 12 lines of 9-mm radial OCT scans with the fovea at the center, the Bruch’s membrane line was plotted and its curvature was measured at 1-µm intervals in each image, which was reflected as a color topography map. For the quantitative analysis of the eye shape, mean absolute curvature and variance of curvature were calculated. Results The color maps allowed staphyloma visualization as a ring ...

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    3. 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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    4. Effects of Sex and Age on the Normal Retinal and Choroidal Structures on Optical Coherence Tomography

      Effects of Sex and Age on the Normal Retinal and Choroidal Structures on Optical Coherence Tomography

      Optical coherence tomography (OCT) has become an essential tool in ophthalmology. Advances in OCT technology have made it possible to measure the thickness of the retina, specific retinal layers, and the choroid. In the present study, the body of the literature documenting the normal retinal and choroidal thickness are reviewed and the effects of sex, age, and axial length on retinal/choroidal thickness are discussed. Macular, retinal layer, and choroidal thickness measured on OCT images in normal eyes showed significant variations by sex and age. Macular retinal thickness was greater in men than in women, especially in the center, inner ...

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    5. Alterations in the Neural and Connective Tissue Components of Glaucomatous Cupping after Glaucoma Surgery using Swept Source Optical Coherence Tomography

      Alterations in the Neural and Connective Tissue Components of Glaucomatous Cupping after Glaucoma Surgery using Swept Source Optical Coherence Tomography

      Purpose: To visualize changes in deep optic nerve head (ONH) structures following glaucoma surgery using (3-dimensional (3D)) swept-source optical coherence tomography (SS-OCT) and to determine the clinical and structural factors associated with postoperative lamina cribrosa (LC) and prelaminar neural tissue (PLT) changes. Methods: In this prospective observational case series, SS-OCT thin-sliced datasets of the ONH covering a 3×3-mm area comprised of 256 B-scans (interval between scans = ∼12µm) were obtained before and 3 months after the surgery and evaluated in 73 eyes of 73 patients with glaucoma. Bruch's membrane opening (BMO) and anterior LC boundary were manually delineated ...

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    6. Three-Dimensional Imaging of Lamina Cribrosa Defects in Glaucoma Using Swept-Source Optical Coherence Tomography

      Three-Dimensional Imaging of Lamina Cribrosa Defects in Glaucoma Using Swept-Source Optical Coherence Tomography

      Purpose. To visualize lamina cribrosa defects using three-dimensional (3D) swept-source optical coherence tomography (SS-OCT), and to determine the factors associated with this feature. Methods. All subjects were examined using an SS-OCT prototype system, which uses a tunable laser as a light source, operated at 100,000 Hz A-scan repetition rate in the 1050-nm wavelength. A 3D raster scan protocol consisting of 256 × 256 A-scans was acquired over a square area of 3 mm × 3 mm centered on the optic disc. En face sectioned volume and serial en face images and orthogonal (horizontal and vertical) serial B-scans were evaluated. Results. A ...

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    7. Three Dimensional Imaging of the Lamina Cribrosa Defects in Glaucoma Using Swept-source Optical Coherence Tomography

      Three Dimensional Imaging of the Lamina Cribrosa Defects in Glaucoma Using Swept-source Optical Coherence Tomography

      Purpose: To visualize and analyze focal lamina cribrosa defects using 3-dimensional (3D) swept-source optical coherence tomography (SS-OCT). Methods: All the subjects were examined using an SS-OCT prototype system, which employs a tunable laser as a light source operated at 100,000 Hz A-scan repetition rate in the 1,050 nm wavelength. Three-dimensional raster scan protocol comprising 256 × 256 A-scans was acquired over a square area of 3 mm × 3 mm centered at the optic disc. En face sectioned volume and serial en face images, which were reconstructed from the 3D data set, and orthogonal (horizontal and vertical) serial B-scan were ...

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    8. Circle and Grid-wise Analyses of Peripapillary Nerve Fiber Layers by Spectral Domain Optical Coherence Tomography in Early Stage Glaucoma

      Circle and Grid-wise Analyses of Peripapillary Nerve Fiber Layers by Spectral Domain Optical Coherence Tomography in Early Stage Glaucoma

      PURPOSE. To study diagnostic performances of circle and grid-wise analyses of peripapillary retinal nerve fiber layer thickness (RNFLT) using spectral domain optical coherence tomography (SD-OCT) in early stage glaucoma. METHODS. Eighty-nine open-angle glaucoma (OAG) eyes (mean deviation, -2.5 ± 1.8 dB) and 89 age-matched normal eyes were studied. Peripapillary RNFLT was analyzed using SD-OCT raster scan in a 6.0 × 6.0 mm area. Averaged RNFLT was calculated over 0.1 × 0.1, 0.21 × 0.21, or 0.42 × 0.42 mm grids in the peripapillary area (grid method), or arcuate sector areas between 2.8 and 4 ...

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    9. 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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    10. 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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    11. Peripapillary Scleral Deformation and Retinal Nerve Fiber Damage in High Myopia Assessed With Swept-Source Optical Coherence Tomography

      Peripapillary Scleral Deformation and Retinal Nerve Fiber Damage in High Myopia Assessed With Swept-Source Optical Coherence Tomography

      Purpose To study peripapillary morphologic changes in highly myopic eyes using swept-source optical coherence tomography at a longer wavelength. Design Prospective cross-sectional study. Methods Peripapillary regions of 196 eyes of 107 patients with high myopia (refractive error, <−8.0 diopters or axial length, >26.0 mm) were analyzed quantitatively and qualitatively with an swept-source optical coherence tomography prototype system that uses a tunable laser light source operated at a 100,000-Hz A-scan repetition rate in the 1-μm wavelength region. The visual field was evaluated by standard automated perimetry. Area of peripapillary atrophy β and presence of scleral protrusion temporal to ...

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    12. High-Resolution Imaging of Retinal Nerve Fiber Bundles in Glaucoma Using Adaptive Optics Scanning Laser Ophthalmoscopy

      High-Resolution Imaging of Retinal Nerve Fiber Bundles in Glaucoma Using Adaptive Optics Scanning Laser Ophthalmoscopy

      Purpose To detect pathologic changes in retinal nerve fiber bundles in glaucomatous eyes seen on images obtained by adaptive optics (AO) scanning laser ophthalmoscopy (AO SLO). Design Prospective cross-sectional study. Methods Twenty-eight eyes of 28 patients with open-angle glaucoma and 21 normal eyes of 21 volunteer subjects underwent a full ophthalmologic examination, visual field testing using a Humphrey Field Analyzer, fundus photography, red-free SLO imaging, spectral-domain optical coherence tomography, and imaging with an original prototype AO SLO system. Results The AO SLO images showed many hyperreflective bundles suggesting nerve fiber bundles. In glaucomatous eyes, the nerve fiber bundles were narrower ...

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    13. Imaging of Localized Retinal Nerve Fiber Layer Defects in Preperimetric Glaucoma Using Spectral-domain Optical Coherence Tomography

      Imaging of Localized Retinal Nerve Fiber Layer Defects in Preperimetric Glaucoma Using Spectral-domain Optical Coherence Tomography

      Purpose: To characterize preperimetric retinal nerve fiber layer (RNFL) defects on speckle noise-reduced spectral-domain optical coherence tomography (SD-OCT), and to determine whether detection of preperimetric RNFL defects can be improved by speckle noise reduction. Patients and Methods: Thirty-two eyes of 32 patients with preperimetric glaucoma and 30 normal eyes of 30 volunteers underwent complete ophthalmic examinations and scanning by speckle noise-reduced SD-OCT (Spectralis), single-scan SD-OCT (RTVue-100), and single-scan time-domain (Stratus) OCT. Results: All 40 RNFL defects identified by photography had angular widths <30 degrees and no disruption of RNFL reflectivity on Spectralis. Circumpapillary RNFL (cpRNFL) boundaries were accurately determined by ...

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    14. A Novel Method to Detect Local Ganglion Cell Loss in Early Glaucoma Using Spectral-Domain Optical Coherence Tomography

      A Novel Method to Detect Local Ganglion Cell Loss in Early Glaucoma Using Spectral-Domain Optical Coherence Tomography

      Purpose: To test the glaucoma-discriminating ability of a new method for detecting local ganglion cell loss using spectral-domain optical coherence tomography (SD-OCT). Methods: This study included 58 eyes from glaucomatous patients and 48 healthy eyes from volunteers. The combined thickness of the ganglion cell layer and inner plexus layer (GCIPL) was measured on a macular cube scan (200 × 200) in Cirrus HD-OCT. GCIPL thicknesses on 360 spokes extending from the inner to the outer radius of a macular elliptical annulus were calculated. The lowest value (minimum GCIPL) was compared to the average GCIPL thickness within the elliptical annulus in the ...

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  2. About Masanori Hangai

    Masanori Hangai, MD, is with the Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan.