1. Articles from Nagahisa Yoshimura

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    1. Lacrimal Canaliculus Imaging Using Optical Coherence Tomography Dacryography

      Lacrimal Canaliculus Imaging Using Optical Coherence Tomography Dacryography

      Lacrimal canaliculus (LC) has a key role in tear drainage, but it is difficult to evaluate the LC in detail, using the existing examinations. In this study, our novel LC imaging technique provided the high-resolution images of LC in a non-invasive manner. Three-dimensional images of LC were acquired via the palpebral conjunctiva from 20 healthy volunteers (20 eyes) and 10 patients with various lacrimal disorders (10 eyes), using optical coherence tomography (OCT) dacryography (OCTD). The LC images showed morphological differences between the vertical and horizontal segments. The function of LC could be evaluated by measuring the intralumen signal intensity over ...

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    2. EVALUATION OF MACULAR ISCHEMIA IN EYES WITH BRANCH RETINAL VEIN OCCLUSION: An Optical Coherence Tomography Angiography Study

      EVALUATION OF MACULAR ISCHEMIA IN EYES WITH BRANCH RETINAL VEIN OCCLUSION: An Optical Coherence Tomography Angiography Study

      Purpose: To quantitatively assess macular morphology and perfusion status using optical coherence tomography, and optical coherence tomography angiography in eyes with branch retinal vein occlusion when macular edema has completely resolved, and to investigate the impact on visual function. Methods: Thirty consecutive eyes with branch retinal vein occlusion–macular edema that resolved after treatment with intravitreal ranibizumab injections were included. Macular sensitivity was measured by microperimetry; defect length of foveal ellipsoid zone band was measured using optical coherence tomography; foveal avascular zone and parafoveal nonperfusion areas (NPA) were measured by optical coherence tomography angiography. Results: The logarithm of minimum angle ...

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    3. 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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    4. Optical Coherence Tomography Angiography to Estimate Retinal Blood Flow in Eyes with Retinitis Pigmentosa

      Optical Coherence Tomography Angiography to Estimate Retinal Blood Flow in Eyes with Retinitis Pigmentosa

      Ophthalmologists sometimes face difficulties in identifying the origin of visual acuity (VA) loss in a retinitis pigmentosa (RP) patient, particularly before cataract surgery: cataract or the retinal disease state. Therefore, it is important to identify the significant factors correlating with VA. Nowadays, retinal blood flow in superficial and deep layers can be estimated non-invasively using optical coherence tomography angiography (OCTA). We estimated blood flow per retinal layer by using OCTA; investigated the correlation between VA and other parameters including blood flow and retinal thickness; and identified the most associated factor with VA in patients with RP. OCTA images in 68 ...

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    5. In Vivo Choroidal Vascular Lesions in Diabetes on Swept-Source Optical Coherence Tomography

      In Vivo Choroidal Vascular Lesions in Diabetes on Swept-Source Optical Coherence Tomography

      Diabetes induces microvascular diseases including diabetic retinopathy and choroidopathy which reciprocally promote the pathogenesis, although optical coherence tomography images of diabetic choroidopathy remains to be documented. Here we evaluated the qualitative characteristics of choroidal vascular lesions in patients with diabetes and their association with diabetic retinopathy on swept-source optical coherence tomography (SS-OCT) images. We retrospectively reviewed 110 consecutive eyes of 110 patients with diabetes and 35 eyes of 35 healthy subjects for whom SS-OCT images (6x6-mm scans centered on the fovea) of sufficient quality were acquired. The curve of chorioretinal sections was flattened using Bruch’s membrane as a reference ...

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    6. Increased Choroidal Vascularity in Central Serous Chorioretinopathy Quantified Using Swept-Source Optical Coherence Tomography

      Increased Choroidal Vascularity in Central Serous Chorioretinopathy Quantified Using Swept-Source Optical Coherence Tomography

      Purpose To investigate the choroidal vascular structural changes in eyes with central serous chorioretinopathy (CSC) by using swept-source optical coherence tomography (SS-OCT). Design Prospective cross-sectional study. Methods We prospectively examined 40 eyes of 34 consecutive patients with CSC. Three-dimensional choroidal images of the macular area, covering 3 × 3 mm and 6 × 6 mm, were obtained with SS-OCT. En face images of the microvasculature of the inner choroid and large choroidal vessel layers were converted to binary images. Choroidal vascular areas were analyzed quantitatively using the binary images. Results The choroidal vascular area was larger in eyes with CSC (the microvasculature ...

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    7. Morphological features in anterior scleral inflammation using swept-source optical coherence tomography with multiple B-scan averaging

      Morphological features in anterior scleral inflammation using swept-source optical coherence tomography with multiple B-scan averaging

      Background/aims To determine the morphological features of anterior scleral inflammation using swept-source optical coherence tomography. Methods In this retrospective observational study, we examined 17 eyes of 14 patients with diffuse anterior scleral inflammation and 13 eyes of 13 young unaffected patients. We compared cross-sectional images of the conjunctiva, episclera and sclera obtained using swept-source optical coherence tomography equipped with a multiple B-scan averaging process between normal eyes and those with episcleritis and scleritis. Results Optical coherence tomography showed that the conjunctival stroma/episclera layer was notably swollen in diseased eyes. The eyes with diffuse anterior scleral inflammation had a ...

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    8. Morphological changes after trabeculectomy in highly myopic eyes with high intraocular pressure by using swept-source optical coherence tomography

      Morphological changes after trabeculectomy in highly myopic eyes with high intraocular pressure by using swept-source optical coherence tomography

      Purpose To investigate the effects of intraocular pressure (IOP) reduction on the eyeball shape in highly myopic eyes with high IOP. Methods This study included patients with an axial length ≥26.5 mm and high IOP ≥22 mmHg after receiving maximum medication, with successful trabeculectomy by a single surgeon, and who underwent swept-source optical coherence tomography (SS-OCT) examinations on preoperative and postoperative ≥3 months periods. Eight eyes of 7 patients were included in the analysis. The morphological changes in the eyeball that occurred pre- and post-operation were analyzed from the SS-OCT images. Results In 6 out of 8 examined eyes ...

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    9. Relationship between Functional and Structural Changes in Diabetic Vessels in Optical Coherence Tomography Angiography

      Relationship between Functional and Structural Changes in Diabetic Vessels in Optical Coherence Tomography Angiography

      The decorrelation signals in optical coherence tomography angiography (OCTA) are derived from the flow of erythrocytes and concomitantly delineate the retinal vasculature. We compared the structural and functional characteristics of vascular lesions visualized in fluorescein angiography (FA), OCTA, and en-face OCT images in 53 eyes (28 patients) with diabetic retinopathy (DR). The foveal avascular zone (FAZ) areas in OCTA images in the superficial layer almost corresponded to those in FA images. The FAZ areas in the en-face OCT images in the superficial layer were smaller than those in the FA images and correlated with each other, which agreed with the ...

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    10. Microvascular Density in Glaucomatous Eyes with Hemifield Visual Field Defects: An Optical Coherence Tomography Angiography Study

      Microvascular Density in Glaucomatous Eyes with Hemifield Visual Field Defects: An Optical Coherence Tomography Angiography Study

      Purpose To investigate microcirculation of peripapillary retina and optic disc in eyes with primary open-angle glaucoma (POAG) and hemifield visual field (VF) defects. Design Prospective observational case series with normal comparison group. Methods Sixty eyes with POAG (41 with superior and 19 with inferior hemifield VF defects) and 21 normal eyes were included in this study. Optical coherence tomography (OCT) angiography was used to acquire 3 × 3 mm optic disc cubes, and circumpapillary retinal nerve fiber layer thickness was also measured using OCT. Vessel densities in the peripapillary superficial retina and whole-signal mode optic disc were individually analyzed based on ...

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    11. Microarchitecture of the Vitreous Body: A High-Resolution Optical Coherence Tomography Study

      Microarchitecture of the Vitreous Body: A High-Resolution Optical Coherence Tomography Study

      Purpose To report novel vitreous body microarchitecture findings using high-resolution spectral-domain OCT (HR-SD-OCT). Design Prospective, cross-sectional study. Methods Horizontal and vertical retinal cross-sectional images that were 10 mm long were acquired from 17 eyes of 17 young healthy volunteers using HR-SD-OCT with enhanced vitreous imaging (EVI). Images were acquired through the fovea, upper vessel arcade, and lower vessel arcade. Results Three new findings on vitreous body microarchitecture were found. First, material located between the retina and posterior vitreous cortex was easily detected in 90% of upper and lower vessel arcade scans. Most scans contained hyper-reflective dots and multilayered hyper-reflective lines ...

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    12. Characterization of Inner Retinal Spots With Inverted Reflectivity on En Face Optical Coherence Tomography in Diabetic Retinopathy

      Characterization of Inner Retinal Spots With Inverted Reflectivity on En Face Optical Coherence Tomography in Diabetic Retinopathy

      Purpose : The purpose of this study was to characterize inner retinal spots with inverted reflectivity on en face images of swept-source optical coherence tomography (SS-OCT) in diabetic retinopathy (DR). Methods : We retrospectively reviewed seventy-five eyes of 75 patients with DR (15 eyes with individual grades of DR severity). We obtained three-dimensional images (6 × 6 mm) centered on the fovea, followed by the generation of en face images. We investigated the morphologic characteristics of spots with inverted reflectivity, which had lower reflectivity than the surrounding areas in the nerve fiber layer (NFL) and higher reflectivity in the ganglion cell layer (GCL ...

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    13. Detection of Myopic Choroidal Neovascularization Using Optical Coherence Tomography Angiography

      Detection of Myopic Choroidal Neovascularization Using Optical Coherence Tomography Angiography

      Purpose To assess whether optical coherence tomography angiography (OCTA) can be used as an alternative to conventional fundus fluorescein angiography (FFA) for the detection of myopic choroidal neovascularization (CNV) Design Validity and reliability analysis Methods Twenty-eight eyes of 26 consecutive Japanese patients with exudative lesions associated with pathological myopia were included in this institutional study. Myopic CNV was detected in 23 eyes of 22 patients; five eyes exhibited simple hemorrhage. The main outcome measure was CNV detection by OCTA and FFA. The CNV area was individually measured by FFA and OCTA. Intraclass correlation coefficients (ICCs) for the CNV area independently ...

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    14. Comparison of retinal vessel measurements using adaptive optics scanning laser ophthalmoscopy and optical coherence tomography

      Comparison of retinal vessel measurements using adaptive optics scanning laser ophthalmoscopy and optical coherence tomography

      Purpose We compared adaptive optics scanning laser ophthalmoscopy (AOSLO) and optical coherence tomography (OCT) vessel caliber measurements. Methods AOSLO videos were acquired from 28 volunteers with healthy eyes. Artery measurements were made 0.5–1 disc diameters away from the optic disc margin. Individual segmented retinal arterial caliber was measured in synchronization with cardiac pulsation and averaged to obtain final horizontal retinal arterial caliber (ACH) and horizontal retinal arterial lumen (ALH). All OCT images were obtained with the Spectralis OCT, a spectral-domain OCT system. Vertical retinal arterial caliber (ACV) and vertical retinal arterial lumen (ALV) were measured on the same ...

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    15. Glaucoma Tube Changes After Suture Lysis Assessed by High-Resolution Anterior Segment Optical Coherence Tomography

      Glaucoma Tube Changes After Suture Lysis Assessed by High-Resolution Anterior Segment Optical Coherence Tomography

      This Ophthalmic Image shows swept-source optical coherence tomography of glaucoma tube changes after Baerveldt glaucoma implant into the ciliary sulcus. A woman developed Takayasu disease and neovascular glaucoma in her early 20s. She underwent cardiovascular bypass surgery, but lost vision in her left eye. When another cardiovascular bypass was planned in her mid-40s, 95% of her right eye angle was closed, but her intraocular pressure (IOP) did not exceed the high teens while receiving glaucoma medications, probably because of reduced ocular circulation. 1 In preparation for the IOP increase with circulation improvement, we performed a Baerveldt glaucoma implant into the ...

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    16. Transient Ciliochoroidal Detachment After Ab Interno Trabeculotomy for Open-Angle Glaucoma A Prospective Anterior-Segment Optical Coherence Tomography Study

      Transient Ciliochoroidal Detachment After Ab Interno Trabeculotomy for Open-Angle Glaucoma A Prospective Anterior-Segment Optical Coherence Tomography Study

      Importance Although trabeculotomy is a glaucoma surgical procedure for modest intraocular pressure (IOP) reduction, some eyes exhibit very low IOP during the early postoperative period. To our knowledge, the reason and its effect have not been investigated. Objectives To investigate ciliochoroidal detachment (CCD) immediately after ab interno trabeculotomy and evaluate its effect on IOP immediately after surgery. Design, Setting, and Participants This prospective, observational, case series was conducted at Kyoto University Hospital, Kyoto, Japan. Patients with open-angle glaucoma who underwent ab interno trabeculotomy using a microsurgical device by a single surgeon between July 1, 2014, and May 31, 2015, were ...

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    17. Influence of Clinical Factors and Magnification Correction on Normal Thickness Profiles of Macular Retinal Layers Using Optical Coherence Tomography

      Influence of Clinical Factors and Magnification Correction on Normal Thickness Profiles of Macular Retinal Layers Using Optical Coherence Tomography

      Purpose To identify the factors which significantly contribute to the thickness variabilities in macular retinal layers measured by optical coherence tomography with or without magnification correction of analytical areas in normal subjects. Methods The thickness of retinal layers {retinal nerve fiber layer (RNFL), ganglion cell layer plus inner plexiform layer (GCLIPL), RNFL plus GCLIPL (ganglion cell complex, GCC), total retina, total retina minus GCC (outer retina)} were measured by macular scans (RS-3000, NIDEK) in 202 eyes of 202 normal Asian subjects aged 20 to 60 years. The analytical areas were defined by three concentric circles (1-, 3- and 6-mm nominal ...

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    18. Changes in morphology and visual function over time in mouse models of retinal degeneration: an SD-OCT, histology, and electroretinography study

      Changes in morphology and visual function over time in mouse models of retinal degeneration: an SD-OCT, histology, and electroretinography study

      Purpose To examine the long-term natural course of retinal degeneration in rd10 and rd12 mice using serial spectral-domain optical coherence tomography (SD-OCT), electroretinography/electroretinograms (ERGs), and histological analysis. Methods Photoreceptor layer thickness and the ability to visualize photoreceptor ellipsoid zones were analyzed using SD-OCT images, and these images were compared with hematoxylin and eosin-stained sections and electron microscopy images. The a- and b-wave amplitudes of the ERGs were analyzed. Results In rd10 mice, the photoreceptor layer thickness rapidly decreased, and the photoreceptor ellipsoid zone was visible on SD-OCT images in 89 and 43 % of eyes of 21 and 33-day-old mice ...

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    19. Structural dissociation of optic disc margin components with optic disc tilting: a spectral domain optical coherence tomography study

      Structural dissociation of optic disc margin components with optic disc tilting: a spectral domain optical coherence tomography study

      Purpose To investigate the dissociation of the Bruch’s membrane opening (BMO) from the scleral canal opening (SO) of the optic disc. Methods In this prospective, cross-sectional, observational study, 101 eyes from 101 patients or suspected subjects of primary open angle glaucoma were included. Enhanced depth imaging spectral domain optical coherence tomography images along the long axis of the optic disc were used to visualize better the deep structures around the optic disc on both the temporal and nasal sides. The distances between the BMO and SO were measured at the temporal and nasal sides of the optic disc, and ...

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    20. Potential Measurement Errors Due to Image Enlargement in Optical Coherence Tomography Imaging

      Potential Measurement Errors Due to Image Enlargement in Optical Coherence Tomography Imaging

      The effect of interpolation and super-resolution (SR) algorithms on quantitative and qualitative assessments of enlarged optical coherence tomography (OCT) images was investigated in this report. Spectral-domain OCT images from 30 eyes in 30 consecutive patients with diabetic macular edema (DME) and 20 healthy eyes in 20 consecutive volunteers were analyzed. Original image (OR) resolution was reduced by a factor of four. Images were then magnified by a factor of four with and without application of one of the following algorithms: bilinear (BL), bicubic (BC), Lanczos3 (LA), and SR. Differences in peak signal-to-noise ratio (PSNR), retinal nerve fiber layer (RNFL) thickness ...

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    21. Macular morphologic findings on optical coherence tomography after microincision vitrectomy for proliferative diabetic retinopathy

      Macular morphologic findings on optical coherence tomography after microincision vitrectomy for proliferative diabetic retinopathy

      Purpose To investigate macular morphology on spectral-domain optical coherence tomography (SD-OCT) images after microincision vitrectomy for vitreous hemorrhage associated with proliferative diabetic retinopathy (PDR). Methods In this retrospective case series, 69 eyes (57 consecutive patients) that underwent 23-gauge microincision vitrectomy for vitreous hemorrhage due to PDR were investigated. Qualitative and quantitative characteristics on SD-OCT images [central retinal thickness, external limiting membrane (ELM), and the ellipsoid zone, epiretinal membranes involving the fovea, and hyperreflective foci at the fovea] were assessed 6 months postoperatively. Their association with the logarithm of the minimum angle of resolution visual acuity (logMAR VA) was evaluated. Results ...

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    22. The Application of Extended Field Imaging to Optical Coherence Tomography

      The Application of Extended Field Imaging to Optical Coherence Tomography

      Since its invention, optical coherence tomography (OCT) has made remarkable advancements in both image resolution and acquisition speed. 1,2 With improvements in both hardware and software, higher resolution and less noisy retinal cross-sectional images can be obtained noninvasively. 3 Recent improvements to commercially available OCT systems have also included increasing scan length. For example, most spectral-domain OCT machines provide line scans that are approximately 9 mm in length. Therefore, a single scan can include the macula and part of the optic disc.

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    23. 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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