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https://www.readbyqxmd.com/read/27902540/macular-perivenous-retinal-whitening-and-presumed-retino-ciliary-sparing-in-a-recurrent-central-retinal-vein-occlusion-associated-with-the-antiphospholipid-syndrome-and-cryoglobulinemia
#1
Dov B Sebrow, Jesse J Jung, Jason Horowitz, Jeffrey G Odel, K Bailey Freund
PURPOSE: Macular perivenous retinal whitening results from hypoperfusion-induced ischemia of the middle retina that can occur in central retinal vein occlusion (CRVO). We describe an unusual case of recurrent CRVO with macular perivenous retinal whitening and retino-ciliary venous sparing in the setting of 2 prothrombotic diseases, antiphospholipid syndrome and Type II cryoglobulinemia. METHODS: A 50-year-old man presented with intermittent loss of vision in his right eye related to a recurrent CRVO...
November 29, 2016: Retinal Cases & Brief Reports
https://www.readbyqxmd.com/read/27895898/nest-covering-in-plovers-how-modifying-the-visual-environment-influences-egg-camouflage
#2
Jolyon Troscianko, Jared Wilson-Aggarwal, Claire N Spottiswoode, Martin Stevens
Camouflage is one of the most widespread antipredator defences, and its mechanistic basis has attracted considerable interest in recent years. The effectiveness of camouflage depends on the interaction between an animal's appearance and its background. Concealment can therefore be improved by changes to an animal's own appearance, by behaviorally selecting an optimal background, or by modifying the background to better match the animal's own appearance. Research to date has largely focussed on the first of these mechanisms, whereas there has been little work on the second and almost none on the third...
October 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/27893849/features-of-age-related-macular-degeneration-in-the-general-adults-and-their-dependency-on-age-sex-and-smoking-results-from-the-german-kora-study
#3
Caroline Brandl, Valentin Breinlich, Klaus J Stark, Sabrina Enzinger, Matthias Aßenmacher, Matthias Olden, Felix Grassmann, Jochen Graw, Margit Heier, Annette Peters, Horst Helbig, Helmut Küchenhoff, Bernhard H F Weber, Iris M Heid
Age-related macular degeneration (AMD) is a vision impairing disease of the central retina characterized by early and late forms in individuals older than 50 years of age. However, there is little knowledge to what extent also younger adults are affected. We have thus set out to estimate the prevalence of early AMD features and late AMD in a general adult population by acquiring color fundus images in 2,840 individuals aged 25 to 74 years of the Cooperative Health Research in the Region of Augsburg project (KORA) in South Germany...
2016: PloS One
https://www.readbyqxmd.com/read/27873005/photoreceptor-spectral-tuning-by-colorful-multilayered-facet-lenses-in-long-legged-fly-eyes-dolichopodidae
#4
D G Stavenga, A Meglič, P Pirih, H Koshitaka, K Arikawa, M F Wehling, G Belušič
The facet lenses of the compound eyes of long-legged flies (Dolichopodidae) feature a striking, interlaced coloration pattern, existing of alternating rows of green-yellow and orange-red reflecting facets, due to dielectric multilayers located distally in the facet lenses (Bernard and Miller. Invest Ophthalmol 7:416-434 (1968). We investigated this phenomenon in the dolichopodid Dolichopus nitidus by applying microspectrophotometry, electron microscopy and optical modeling. The measured narrow-band reflectance spectra, peaking at ~540 and ~590 nm with bandwidth ~105 nm, are well explained by a refractive index oscillating sinusoidally in six periods around a mean value of about 1...
November 21, 2016: Journal of Comparative Physiology. A, Neuroethology, Sensory, Neural, and Behavioral Physiology
https://www.readbyqxmd.com/read/27872754/evaluation-of-contrast-sensitivity-chromatic-vision-and-reading-ability-in-patients-with-primary-open-angle-glaucoma
#5
Maria P Bambo, Blanca Ferrandez, Noemi Güerri, Isabel Fuertes, Beatriz Cameo, Vicente Polo, Jose M Larrosa, Elena Garcia-Martin
Purpose. To compare contrast sensitivity, acquired color vision deficiency, and reading ability in patients with glaucoma at different stages of the disease and to establish correlations between visual field parameters and visual function scores. Methods. This prospective cross-sectional study included 121 glaucoma patients. Subjects with a diagnosis of chronic open angle glaucoma were recruited and classified according to Hodapp-Parrish-Anderson criteria. Patients with severe visual field defects were excluded because they were older, which could bias the interpretation of visual function tests...
2016: Journal of Ophthalmology
https://www.readbyqxmd.com/read/27858936/retinal-ganglion-cell-and-axonal-loss-in-optic-neuritis-risk-factors-and-visual-functions
#6
T H Lee, Y S Ji, S W Park, H Heo
PurposeThe peripapillary retinal nerve fiber layer (pRNFL) and the macular ganglion cell-inner plexiform layer (GCIPL) are important predictive factors for the prognosis of optic neuritis (ON). We investigated the risk factors for pRNFL and GCIPL thinning in ON and its relationship with visual function.Patients and methodsWe analyzed 33 eyes of 33 patients with a first attack of unilateral ON. Patients were divided into two groups according to pRNFL and GCIPL thinning, using spectral-domain optical coherence tomography...
November 18, 2016: Eye
https://www.readbyqxmd.com/read/27857872/the-lamb-s-head-as-a-model-for-surgical-skills-development-in-endonasal-surgery
#7
Luíza Baptista Mallmann, Otávio Bejzman Piltcher, Gustavo Rassier Isolan
Objectives To test the viability of a lamb's head model for sinonasal surgery training in Brazil by comparing performance of endoscopic procedures in the septum and inferior turbinates. Design Prospective study. Settings Universidade Federal do Rio Grande do Sul (2015). Participants Ten physicians performed septoplasty, inferior turbinoplasty, and middle turbinectomy on 30 lamb's heads. Main Outcome Measures Degree of difficulty and similarity, opinion of tissue color and texture, and degree of satisfaction...
December 2016: Journal of Neurological Surgery. Part B, Skull Base
https://www.readbyqxmd.com/read/27856005/mobile-universal-lexicon-evaluation-system-mules-test-a-new-measure-of-rapid-picture-naming-for-concussion
#8
Lucy Cobbs, Lisena Hasanaj, Prin Amorapanth, John-Ross Rizzo, Rachel Nolan, Liliana Serrano, Jenelle Raynowska, Janet C Rucker, Barry D Jordan, Steven L Galetta, Laura J Balcer
OBJECTIVE: This study introduces a rapid picture naming test, the Mobile Universal Lexicon Evaluation System (MULES), as a novel, vision-based performance measure for concussion screening. The MULES is a visual-verbal task that includes 54 original photographs of fruits, objects and animals. We piloted MULES in a cohort of volunteers to determine feasibility, ranges of picture naming responses, and the relation of MULES time scores to those of King-Devick (K-D), a rapid number naming test...
November 4, 2016: Journal of the Neurological Sciences
https://www.readbyqxmd.com/read/27851900/residual-perception-of-biological-motion-in-cortical-blindness
#9
Ruffieux Nicolas, Ramon Meike, Lao Junpeng, Colombo Françoise, Stacchi Lisa, Borruat François-Xavier, Accolla Ettore, Annoni Jean-Marie, Caldara Roberto
From birth, the human visual system shows a remarkable sensitivity for perceiving biological motion. This visual ability relies on a distributed network of brain regions and can be preserved even after damage of high-level ventral visual areas. However, it remains unknown whether this critical biological skill can withstand the loss of vision following bilateral striate damage. To address this question, we tested the categorization of human and animal biological motion in BC, a rare case of cortical blindness after anoxia-induced bilateral striate damage...
November 13, 2016: Neuropsychologia
https://www.readbyqxmd.com/read/27848022/is-there-a-change-in-the-quality-of-life-comparing-the-micro-invasive-glaucoma-surgery-migs-and-the-filtration-technique-trabeculectomy-in-glaucoma-patients
#10
Milena Pahlitzsch, Matthias K J Klamann, Marie-Luise Pahlitzsch, Johannes Gonnermann, Necip Torun, Eckart Bertelmann
PURPOSE: This study was conducted to assess the impact on the Quality of Life (QOL) of micro-invasive glaucoma surgery (MIGS: iStent, Trabectome) and a penetrating technique such as Trabeculectomy (TE). METHODS: This study evaluated 88 eyes of 88 open angle glaucoma patients undergoing glaucoma surgery: 43 (mean age 72.8 ± 8.8y, female 59.5 %, male 40.5 %) Trabectome (NeoMedix, Inc., Tustin, CA, USA), 20 (mean age 68.6 ± 16.4y, female 60 %, male 40 %) iStent (Glaucos Corporation, Laguna Hills, CA, USA), and 25 TE patients (mean age 74...
November 15, 2016: Graefe's Archive for Clinical and Experimental Ophthalmology
https://www.readbyqxmd.com/read/27847514/tracking-algorithm-of-multiple-pedestrians-based-on-particle-filters-in-video-sequences
#11
Hui Li, Yun Liu, Chuanxu Wang, Shujun Zhang, Xuehong Cui
Pedestrian tracking is a critical problem in the field of computer vision. Particle filters have been proven to be very useful in pedestrian tracking for nonlinear and non-Gaussian estimation problems. However, pedestrian tracking in complex environment is still facing many problems due to changes of pedestrian postures and scale, moving background, mutual occlusion, and presence of pedestrian. To surmount these difficulties, this paper presents tracking algorithm of multiple pedestrians based on particle filters in video sequences...
2016: Computational Intelligence and Neuroscience
https://www.readbyqxmd.com/read/27845179/spatial-summation-improves-bird-color-vision-in-low-light-intensities
#12
Peter Olsson, David Wilby, Almut Kelber
Color guides many important behaviors in birds. Previously we have shown that the intensity threshold for color discrimination in the chicken depends on the color contrast between stimuli and their brightness. The birds could discriminate larger color contrasts and brighter colors in lower light intensities. We suggested that chickens use spatial summation of cone signals to maintain color vision in low light levels. Here we tested this hypothesis by determining the intensity thresholds of color discrimination using similar stimuli, patterns of grey tiles of varying intensity interspersed with color tiles, adjusted for this specific aim...
November 25, 2016: Vision Research
https://www.readbyqxmd.com/read/27843942/color-matching-and-blending-effect-of-universal-shade-bulk-fill-resin-composite-in-resin-composite-models-and-natural-teeth
#13
Rasha M Abdelraouf, Nour A Habib
Objectives. To assess visually color-matching and blending-effect (BE) of a universal shade bulk-fill-resin-composite placed in resin-composite-models with different shades and cavity sizes and in natural teeth (extracted and patients' teeth). Materials and Methods. Resin-composite-discs (10 mm × 1 mm) were prepared of universal shade composite and resin-composite of shades: A1, A2, A3, A3.5, and A4. Spectrophotometric-color-measurement was performed to calculate color-difference (ΔE) between the universal shade and shaded-resin-composites discs and determine their translucency-parameter (TP)...
2016: BioMed Research International
https://www.readbyqxmd.com/read/27837238/the-flicker-fusion-frequency-of-budgerigars-melopsittacus-undulatus-revisited
#14
Jannika E Boström, Nicola K Haller, Marina Dimitrova, Anders Ödeen, Almut Kelber
While color vision and spatial resolution have been studied in many bird species, less is known about the temporal aspects of bird vision. High temporal resolution has been described in three species of passerines but it is unknown whether this is specific to passerines, to small actively flying birds, to insectivores or to birds living in bright habitats. Temporal resolution of vision is commonly tested by determining the flicker fusion frequency (FFF), at which the eye can no longer distinguish a flickering light from a constant light of equal intensity at different luminances...
November 11, 2016: Journal of Comparative Physiology. A, Neuroethology, Sensory, Neural, and Behavioral Physiology
https://www.readbyqxmd.com/read/27828102/perifoveal-l-and-m-cone-driven-temporal-contrast-sensitivities-at-different-retinal-illuminances
#15
Cord Huchzermeyer, Jan Kremers
We established a protocol using a well-established LED stimulator to measure temporal contrast sensitivities driven by sine-wave modulation of L- and M-cones in the perifovea using triple silent substitution. The stimulus was presented in an annular field (2° inner diameter, 13° outer diameter). We validated this technique by studying the contrast sensitivity of three color normal observers at 10 different temporal frequencies (between 1 and 28 Hz) over a large range of retinal illuminances (between 0.07 and 587 phot Td), spanning the complete mesopic range...
October 1, 2016: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
https://www.readbyqxmd.com/read/27824543/giant-cell-arteritis-and-polymyalgia-rheumatica-2016-update
#16
REVIEW
Gideon Nesher, Gabriel S Breuer
Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are both more common among people of North European decent than among Mediterranean people. Women are 2-3 times more commonly affected. Giant cell arteritis and PMR are extremely rare before age 50 years. Polymyalgia rheumatica may be "isolated" or associated with GCA. There is increased expression of inflammatory cytokines in temporal arteries of PMR patients, without overt histological evidence of arteritis. One-third of "isolated" PMR patients have vascular uptake in positron emission tomography (PET) scans, suggesting clinically unrecognized, "hidden" GCA...
October 31, 2016: Rambam Maimonides Medical Journal
https://www.readbyqxmd.com/read/27822354/the-whole-is-other-than-the-sum-perceived-contrast-summation-within-color-and-luminance-plaids
#17
Avital S Cherniawsky, Kathy T Mullen
The apparent contrast of a plaid is a reflection of the neural relationship between the responses to its two orthogonal component gratings. To investigate the perceived contrast summation of the responses to component gratings in plaids, we compared the apparent contrasts of monocular plaids to a component grating presented alone across chromaticity and spatial frequency. Observers performed a contrast-matching task for red-green color and luminance stimuli at low- and medium-spatial frequencies. Using the measured points of subjective equality between plaids and gratings, we evaluate perceived contrast summation across conditions, which may vary between 1 (no summation) and 2 (full summation)...
September 2016: I-Perception
https://www.readbyqxmd.com/read/27820754/en-face-optical-coherence-tomography-of-multiple-evanescent-white-dot-syndrome
#18
Daniel Su, David Xu, Nopasak Phasukkijwatana, David Sarraf
PURPOSE: To report novel en face imaging findings of multiple evanescent white dot syndrome. METHODS: A 25-year-old woman presented with photopsia and vision loss affecting the left eye. Ophthalmic examination, color fundus photography, fluorescein angiography, spectral domain optical coherence tomography (SD-OCT), fundus autofluorescence, en face OCT, and OCT angiography were performed. RESULTS: The diagnosis of multiple evanescent white dot syndrome was made based on clinical examination and multimodal imaging findings...
November 3, 2016: Retinal Cases & Brief Reports
https://www.readbyqxmd.com/read/27820752/electronegative-electroretinogram-in-achromatopsia
#19
Craig S Schallhorn, David B Granet, Henry A Ferreyra
PURPOSE: To report novel electroretinographic findings in a genetically confirmed case of achromatopsia. METHODS: A patient with a history of childhood nystagmus, photoaversion, and absent color vision was examined. Electroretinography and fundus examination were performed under anesthesia at the time of corrective surgery for nystagmus. Genomic DNA isolated from peripheral blood was directly sequenced for variations in the CNGA3 and CNGB3 genes. RESULTS: Ophthalmoscopic examination revealed no distinct abnormalities...
November 3, 2016: Retinal Cases & Brief Reports
https://www.readbyqxmd.com/read/27813519/comparison-of-vision-related-quality-of-life-in-primary-open-angle-glaucoma-and-dry-type-age-related-macular-degeneration
#20
S Karadeniz Ugurlu, A E Kocakaya Altundal, M Altin Ekin
PurposeTo compare quality of life (QoL) in patients with primary open-angle glaucoma (POAG) and dry-type age-related macular degeneration (AMD) with similar best-corrected visual acuity.MethodsAge-, sex-, and visual acuity-matched POAG and dry AMD patients were included in the study. Each patient performed 24-2 and 10-2 SITA standard visual field tests. Contrast sensitivity was evaluated with CSV-1000 HGT instrument. The 25 item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) was used to analyze QoL...
November 4, 2016: Eye
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