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Purpose: We introduce a new method to observe the morphologic features of the vitreous with spectral-domain optical coherence tomography (SD-OCT) by evaluating and describing the posterior vitreous structure of various selected cases using enhanced high-density (HD) line mode., Methods: This is a descriptive case series of SD-OCT images with enhanced HD line at Denver Health Medical Center, University of Colorado School of Medicine, in 2014. The medical records with ocular images for these patients were analyzed., Results: Enhanced HD line in vitreoretinal mode with SD-OCT offered wide images with well-visible vitreoretinal interface. The posterior precortical vitreous pocket (PPVP), often mistaken as a posterior vitreous detachment on standard retina-based cross line mode, was easily identified. Vitreomacular adhesion and traction, absence or presence of connecting channels between PPVP and Cloquet's canal, liquefied vitreous lacuna, and emulsified silicone oil droplet-layer could be observed., Conclusions: SD-OCT using enhanced HD line in vitreoretinal mode enables clear visualization of the posterior vitreous structure and often reclassifies patients previously thought to have a posterior vitreous detachment.

Purpose: To propose a model that measures the effect of intravitreal bevacizumab (IVB) on relatively healthy retina. The purpose is to analyze the remote effect of a branch retinal vein occlusion in the healthy retina, to determine the response it may have to IVB, and to determine if IVB has an atrophic effect on the healthy retina., Methods: Retrospective, longitudinal comparative analysis of patients with branch retinal vein occlusion treated with IVB. Eyes were divided into experimental (branch retinal vein occlusion eye) and control (contralateral eye) groups. Each eye was analyzed for thickness and area. Thickness measurements were performed for total retinal thickness, inner retina thickness, and outer retina thickness. Area was measured for photoreceptors, choroid, and total retina., Results: Eighteen eyes of 9 patients. For thickness analysis, 1,050 scans were studied, and 126 measurements were performed on 42 scans for area analysis. No difference was observed for thickness, except for inner retina thickness. No difference was observed for area. No difference was observed when analyzing a cumulative exposure to IVB., Conclusion: There is no evidence to suggest an atrophic effect caused by IVB when analyzing thickness or area in this experiment. This model could be used to analyze the long-term safety of IVB in larger studies.

This paper uses computer modeling to estimate the progressive decline in oxygenation that occurs in the human diabetic retina after years of slowly progressive ischemic insult. An established model combines diffusion, saturable consumption, and blood capillary sources to determine the oxygen distribution across the retina. Incorporating long-term degradation of blood supply from the retinal capillaries into the model yields insight into the effects of progressive ischemia associated with prolonged hyperglycemia, suggesting time-scales over which therapeutic mitigation could have beneficial effect. A new extension of the model for oxygen distribution introduces a feedback mechanism for vasodilation and its potential to prolong healthy retinal function., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: To evaluate and compare the perfluorocarbon liquid, silicone oil, and viscoelastic against standard saline, in their ability to dampen the impact force of a foreign body, dropped within the eye. In an experimental surgical model in where cohesive and adhesive forces of the substances are not enough to float heavy-than-water foreign bodies., Methods: A model of ophthalmic surgery was constructed. A BB pellet was dropped from 24 mm onto a force transducer through four different fluids: balanced salt solution, perfluoro-n-octane, viscoelastic, and silicone oil. The impact energy (force) for each case was measured and recorded by the force transducer. The mean force of impact for each fluid was compared using the Student t-test., Results: Silicone oil resulted in the lowest force of impact. Both silicone oil and viscoelastic dampened the impact an order of magnitude more than perfluoro-n-octane and balanced salt solution., Conclusions: Silicone oil and viscoelastic cushioned the force from a dropped BB. They may be useful adjuncts to prevent iatrogenic retinal injury during vitrectomy for intraocular foreign body removal., (© 2012 The Authors. Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.)

Purpose: To study the intravitreal application of silicon quantum dots (QDs) and their capabilities to deliver electrical stimulation to the retinal cells and to assess the potential effect on retinal electrophysiology and anatomy., Methods: A Royal College of Surgeon rat model of retinal degeneration was used in this study. A total of 32 eyes were used, divided in four groups of 8 eyes each; the first group received the silicon-based QD, the second group received an inactive gold-based QD, the third group received a sham injection, and the fourth group was used as a control. An electroretinogram (ERG) was done at baseline and thereafter every week for 9 weeks. At the end of the follow-up, eyes were collected for further pathologic analysis and nuclei cell counts., Results: Eyes within the silicon-based QD group showed a definite but transient increase in the waves of the ERG, especially in the rod response compared with the sham and control groups (P < 0.05). The pathologic examination demonstrated a higher nuclei count in the QD group, consistent with a higher cell survival rate than that in the sham and control groups in which cells degenerated as expected., Conclusions: Intravitreal injection of silicon-based QD seems to be safe and well tolerated, with no evident toxic reaction and demonstrates a beneficial effect by prolonging cell survival rate and improving ERG patterns in a well-established model of retinal degeneration. (ClinicalTrials.gov numbers NCT00407602, NCT01490827.).

Purpose: To characterize retinal electrophysiologic and psychophysical abnormalities associated with membranoproliferative glomerulonephritis type II., Methods: Three adults with membranoproliferative glomerulonephritis type II were studied. Retinal function was measured psychophysically (automated perimetry, Farnsworth D-15 color vision testing, and dark adaptometry) and electrophysiologically (full-field flash electroretinography and electro-oculography)., Results: Two symptomatic individuals had prominent drusenlike deposits and retinal pigment epithelial disturbances, findings characteristic of membranoproliferative glomerulonephritis type II retinopathy. These individuals had mild visual field and color vision abnormalities, prolonged dark adaptation, and delayed electroretinographic dark-adapted dim and bright flash responses of normal amplitude. The electro-oculogram of the most severely affected individual was abnormal. The third individual who was asymptomatic had the mildest fundus abnormalities and exhibited normal psychophysical and electrophysiologic responses., Conclusions: Membranoproliferative glomerulonephritis type II retinopathy may be associated with symptomatic and measurable psychophysical and electrophysiologic abnormalities of retinal function.