Category: Peer-reviewed

期刊一览

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电离辐射可被用于新生血管性年龄相关性黄斑变性(AMD)的辅助治疗吗？在INTREPID研究中，Jackson (p. 1893) 等人采用低压、外照射放疗(SRT)，发现SRT能显著减少AMD患者重复进行玻璃体腔ranibizumab注射

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Quantitative Classification of Eyes with and without Intermediate Age-related Macular Degeneration Using Optical Coherence Tomography – Corrected Proof

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Objective: To define quantitative indicators for the presence of intermediate age-related macular degeneration (AMD) via spectral-domain optical coherence tomography (SD-OCT) imaging of older adults.Design: Evaluation of diagnostic test and technology.Participants and Controls: One eye from 115 elderly subjects without AMD and 269 subjects with intermediate AMD from the Age-Related Eye Disease Study 2 (AREDS2) Ancillary SD-OCT Study.Methods: We semiautomatically delineated the retinal pigment epithelium (RPE) and RPE drusen complex (RPEDC, the axial distance from the apex of the drusen and RPE layer to Bruch’s membrane) and total retina (TR, the axial distance between the inner limiting and Bruch’s membranes) boundaries. We registered and averaged the thickness maps from control subjects to generate a map of “normal” non-AMD thickness. We considered RPEDC thicknesses larger or smaller than 3 standard deviations from the mean as abnormal, indicating drusen or geographic atrophy (GA), respectively. We measured TR volumes, RPEDC volumes, and abnormal RPEDC thickening and thinning volumes for each subject. By using different combinations of these 4 disease indicators, we designed 5 automated classifiers for the presence of AMD on the basis of the generalized linear model regression framework. We trained and evaluated the performance of these classifiers using the leave-one-out method.Main Outcome Measures: The range and topographic distribution of the RPEDC and TR thicknesses in a 5-mm diameter cylinder centered at the fovea.Results: The most efficient method for separating AMD and control eyes required all 4 disease indicators. The area under the curve (AUC) of the receiver operating characteristic (ROC) for this classifier was >0.99. Overall neurosensory retinal thickening in eyes with AMD versus control eyes in our study contrasts with previous smaller studies.Conclusions: We identified and validated efficient biometrics to distinguish AMD from normal eyes by analyzing the topographic distribution of normal and abnormal RPEDC thicknesses across a large atlas of eyes. We created an online atlas to share the 38 400 SD-OCT images in this study, their corresponding segmentations, and quantitative measurements.Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references.

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A molecular mechanism of optic nerve regeneration in fish: the retinoid signaling pathway

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Publication date: Available online 28 August 2013
Source:Progress in Retinal and Eye Research
Author(s): Satoru Kato , Toru Matsukawa , Yoshiki Koriyama , Kayo Sugitani , Kazuhiro Ogai
The fish optic nerve regeneration process takes more than 100 days after axotomy and comprises four stages: neurite sprouting (1–4 days), axonal elongation (5–30 days), synaptic refinement (35–80 days) and functional recovery (100–120 days). We screened genes specifically upregulated in each stage from axotomized fish retina. The mRNAs for heat shock protein 70 and insulin-like growth factor-1 rapidly increased in the retinal ganglion cells soon after axotomy and function as cell-survival factors. Purpurin mRNA rapidly and transiently increased in the photoreceptors and purpurin protein diffusely increased in all nuclear layers at 1–4 days after injury. The purpurin gene has an active retinol-binding site and a signal peptide. Purpurin with retinol functions as a sprouting factor for thin neurites. This neurite-sprouting effect was closely mimicked by retinoic acid and blocked by its inhibitor. We propose that purpurin works as a retinol transporter to supply retinoic acid to damaged RGCs which in turn activates target genes. We also searched for genes involved in the second stage of regeneration. The mRNA of retinoid-signaling molecules increased in retinal ganglion cells at 7–14 days after injury and tissue transglutaminase and neuronal nitric oxide synthase mRNAs, RA-target genes, increased in retinal ganglion cells at 10–30 days after injury. They function as factors for the outgrowth of thick, long neurites. Here we present a retinoid-signaling hypothesis to explain molecular events during the early stages of optic nerve regeneration in fish.

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Macular Structure Parameters as an Automated Indicator of Paracentral Scotoma in Early Glaucoma – Corrected Proof

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Purpose: To evaluate the predictive ability of macular parameters defined in the significance map created using spectral-domain optical coherence tomography (SD-OCT) for paracentral visual field defects in early glaucoma.Design: Prospective comparative study.Methods: We studied 78 early-glaucomatous eyes of 78 patients, who underwent SD-OCT and standard automated perimetry 10-2. Macular layer parameters included the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL) + inner plexiform layer (IPL), and RNFL + GCL + IPL. The minimal distance between the area with abnormal (P < 1%) thickness and foveal center was defined as the shortest distance. A wider area of an abnormally thinned (<1%) region, within either an inferior or a superior hemicircle with a diameter of 6 mm centered at the fovea, was defined as the macular abnormal area. A circumpapillary RNFL parameter was defined in its 36 sectors. Areas under the receiver operating characteristic curves (ROCs) were calculated to discriminate between eyes with (n = 39) and without (n = 39) paracentral visual field defects in the central 5 degrees.Results: Measurement reproducibility was almost perfect in the macular parameters at P < 1% (intraclass correlation, 0.907–0.942). Areas under the ROC were significantly higher (P ≤ 0.01) in the macular parameters (0.870–0.930), including the shortest distance of GCL + IPL/RNFL + GCL + IPL, and the macular abnormal area of RNFL/GCL + IPL/RNFL + GCL + IPL than in the circumpapillary RNFL parameter (0.676). When specificity was fixed at ≥90%, the shortest distance of GCL + IPL (area under the ROC = 0.874) and the macular abnormal area of RNFL (area under the ROC = 0.894) showed sensitivities greater than 50%.Conclusions: Macular structural parameters defined on an SD-OCT significance map may be potentially useful predictors of the presence of paracentral scotoma.

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Mechanism of Retinal Pigment Epithelium Tear Formation Following Intravitreal Anti–Vascular Endothelial Growth Factor Therapy Revealed by Spectral-Domain Optical Coherence Tomography – Corrected Proof

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Purpose: To demonstrate the mechanism by which retinal pigment epithelium (RPE) tears occur in eyes with neovascular age-related macular degeneration (AMD) treated with intravitreal anti–vascular endothelial growth factor (VEGF) agents using spectral…

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