bluuebunny/crossref_metadata_2025_split huggingface dataset:
Developing a clinically viable protocol for measuring and analysing the human contrast sensitivity function on a standard computerised chart
Authors: DONALD J , LI J , SAROSSY M , WEYMOUTH A 
Published: August 2014

AbstractPurpose Contrast sensitivity testing is an important part of visual assessment and can identify visual deficits that go undetected by measuring visual acuity (VA) alone. Despite this, contrast sensitivity testing is rarely performed clinically due to the expensive processes required and limited test availability, with few spatial frequencies used. Further, gratings can be difficult for subjects to learn and results are often not standardized. We developed and tested a convenient, inexpensive protocol using Snellen optotypes to measure the CSF using a widely available computerised VA chart. Effects of blur and neutral density (ND) light attenuation were analysed to evaluate the technique under different conditions.Methods 34 eyes of 34 subjects were tested monocularly under photopic conditions. Subjects had corrected VA of 6/4.8 (or better) and normal ocular health. A computerised chart (Luneau) was used to measure contrast sensitivity thresholds across 19 spatial frequencies between 0.9 and 60.0 cpd using an ascending Method of Limits. This was repeated with +1.50DS blur and a 2.9 ND filter. CSFs were analysed and modeled using R and Prism to extract useful parameters: the area under the log10 CSF (AULCSF), CSF peak, high‐ and low‐spatial frequency limits.Results A quadratic function was found to best fit the pooled log CSF data, minimising cross‐validation error. The AULCSF was calculated between log spatial frequencies of 0.6 and 1.4 using integration of the fitted quadratic function. Mean AULCSF was 1.82±0.133.Conclusion Our method can measure, display and calculate the normal CSF. This can be used to compare and assess the CSFs of patients with ocular diseases.
Flash visual evoked potentials (FVEP) in various stimulation conditions
Authors: POJDA‐WILCZEK D 
Published: August 2014

AbstractPurpose Comparison between the results of FVEP examinations conducted with various stimulators (Ganzfeld, Mini Ganzfeld i Flash Goggles) as well as for opened and closed eyes.Methods 17 volunteers (34 eyes), including 11 females, aged 23‐56 (average age: 30 years) have been examined with Roland Consult electrophysiological equipment. Basing on Wilcoxon signed‐rank test the amplitude and the latency of P2 wave have been compared: 1. of results acquired with each of three stimulators; 2. of results acquired with eyes opened and eyes closed.Results Mean P2 amplitude (latency) acquired with Ganzfeld stimulation amounted to 12 µV (130 ms), acquired with Mini Ganzfeld stimulation amounted to 7 µV (124 ms) and acquired with Flash Goggles amounted to 9 µV (113 ms). The results statistically significantly differed (p < 0,0001) between all compared stimulators. Mean P2 amplitude (latency) acquired with Ganzfeld stimulation amounted to 12 µV (130 ms), acquired with Mini Ganzfeld stimulation amounted to 7 µV (124 ms) and acquired with Flash Goggles amounted to 9 µV (113 ms) with eyes opened and accordingly 11 µV (131 ms), 9 µV (126 ms) and 6 µV (120 ms) with eyes closed. The results for eyes opened and eyes closed statistically significantly differed (p < 0,001) for Mini Ganzfeld as well as for Flash Goggles stimulators.Conclusion The amplitude and latency of P2 FVEP acquired with different stimulators cannot be compared. Keeping eyes closed does not significantly alter the amplitude and latency of P2 FVEP only in case of Ganzfeld stimulation. The results acquired with other stimulators can be faulty if the patient closed eyes during examination.
Simulation of DME changes on OCT
Authors: CORREIA A , ARAÚJO A , BARBEIRO S , CARAMELO F , SERRANHO P , MORGADO M , BERNARDES R 
Published: August 2014

AbstractPurpose To identify the changes at the cellular level responsible for the differences seen in OCT scans of DME patients.Methods Cirrus HD‐OCT (Carl Zeiss Meditec, Dublin, CA, USA) scans of DME eyes (12 eyes of 8 patients: 68.9±7.5 yrs) and healthy control (HC) eyes (12 eyes of 11 controls: 63.0±3.6 yrs) were acquired from our database. The ONL was segmented by a human grader (AC) and each segmentation was aligned to its upper boundary, averaged into an A‐scan and then normalized by the intensity at the RPE to discard the effect of media opacities. To understand the significant differences found between the profiles of DME and HC, a Monte Carlo method for simulating light scattering with a model of the ONL was implemented. The inputs for the method are calculated using Mie theory by assuming that the ONL may be modelled as a homogeneous medium filled with nuclei. Changes in each model parameter (e.g. nucleus' size) were tested and compared with the measured profile to identify which cellular change could best reproduce the OCT differences found between HC and DME patients. Moreover, the DME group was divided into those without significant visible changes and those with increased ONL volume.Results The simulation method successfully reproduced the differences observed between the HC and DME groups. For the DME cases with increased volume, it was possible to match the simulated and acquired profiles by using the measured increase in ONL thickness. In the DME case with no significant changes, it was necessary to increase only the nucleus size to be able to reproduce the measured profiles.Conclusion The method proposed is capable of reproducing the reflectivity changes measured on OCT scans of the ONL of DME eyes and to justify these at the subcellular level.
Visual impairment in diabetic patients with and without established blood‐retinal barrier leakage and relation with the status of the blood‐brain barrier
Authors: QUENDERA B , AMORIM A , CORDEIRO M , FERREIRA C , MARQUES J , BERNARDES R , REIS A , RIBEIRO L , CASTELO‐BRANCO M 
Published: August 2014

AbstractPurpose To assess visual impairment in diabetic patients with and without established blood‐retinal barrier leakage and relation with the status of the blood‐brain barrier.Methods We assessed 37 diabetic patients (29 type2; mean Hb1Ac 7.93[1.44]) using four different approaches: a two‐alternative forced‐choice multi‐psychophysical channel test for speed discrimination and achromatic contrast as well as chromatic L, M and S cone contrast discrimination; multifocal electrorretinography(mfERG) and brain barrier integrity assessment using a permeability measure Ktrans for dynamic contrast enhanced MRI (Cramer et. al, 2013) in 4 regions of interest(ROIs). We selected two diabetic groups with and without measured retinal barrier leakage. Spearman’s rank were used for correlations and Mann‐Whitney U test for comparison between groups for a set p value threshold of 0.05.Results We found that presence of retinal leakage was not associated with changes in blood brain barrier permeability at any of the studied ROIs. Interestingly we found, in particular in diabetic type 2 patients, significant negative correlations between the amplitude and/or implicit time of N1 and P1 components of the multifocal electrorretinogram and brain leakage, for the most external stimulation rings. Psychophysical performance was impaired in particular for S but was not correlated with barrier status.Conclusion Our findings suggest that retina and brain blood barriers are patho physiologically unrelated in diabetes. We found a direct correlation between neurophysiological measures and brain barrier damage, suggesting that both may have a direct common cause.
Chromatic pupillometry for assessment functional rod and cone patterns in Usher syndrome patients
Authors: SLIESORAITYTE I , MACHIN C , MAKOWIECKA K , MOHAND‐SAID S , SAHEL J 
Published: August 2014

AbstractPurpose The aim of the study was to characterize the functional rod and cone patterns using chromatic pupillometry in Usher syndrome patients.Methods Prospective case series study enrolled 45 Usher syndrome patients. All patients underwent in‐depth phenotypic examination. Functional rod and cone patterns were obtained using custom‐made chromatic pupillometer(AMTech, Dosenheim, Germany). Pupil diameter was recorded monocular in response to red (640 nm) and blue (462 nm) light stimuli for varied intensity levels (ranged from 1000 cd/m2 to 0.001cd/m2). Response amplitudes were analyzed and compared to the clinical phenotype.Results Pupil responses to rod‐ and cone‐weighted stimulation were significantly diminished in all Usher syndrome patients for all intensity levels (mean decrease 60% and 30%, respectively p<0.001). Lower rod‐weighted responses were related with decreased b‐wave amplitude in full field ERG (r=0.37,p<0.001). Decreased cone‐weighted responses were correlated with diminished photopic ERG b‐wave amplitude (r=0.43,p<0.001) and mfERG amplitudes (r=0.65,p<0.001). Higher cones‐weighted responses were associated with preserved cone mosaic in adaptive optics and presence of inner/outer segment in optical coherence tomography, although not always related with preserved visual field and visual acuity. Rod‐ and cone‐weighted responses were recordable even in a very advanced Usher syndrome cases associated with abolished ERG.Conclusion Chromatic pupillography is an objective tool to assess functional rod and cone patterns in Usher syndrome, which potentially could be used as an outcomes measure to assess safety and efficacy in therapy trials, in particularly in advanced cases.
Curable forms of childhood strabismus
Authors: MOHNEY B 
Published: August 2014

AbstractBackground: The literature on the management of childhood strabismus emphasizes some subtypes while ignoring others, based upon the experience of the author or the popularity of the topic, and are often from single‐institution, tertiary‐care referral centers. The purpose of this study is to review which forms of childhood strabismus are potentially curable. Methods: This overview identified surgically curable forms of strabismus, defined as a life‐long result of orthotropia to small angle strabismus with > 50 seconds or better of stereoacuity and normal ocular motility. Results: Children with a developmental disorder, sensory strabismus, convergence insufficiency, dissociated strabismus and Browns syndrome were excluded. Curable forms of childhood strabismus included some children with partial sixth nerve palsy, accommodative and acquired nonaccommodative estropia and, in rare instances, a small percentage of children with intermittent exotropia. Conclusions: In declining order, some children with partial sixth nerve palsy, accommodative esotropia, acquired nonaccommodative esotropia, and only a handful with intermittent exotropia, can be said to be curable forms of childhood strabismus.
What genetics has taught us about keratoconus
Authors: VINCENT AL 
Published: August 2014

AbstractKeratoconus most likely represents complex disease, with different modes of inheritance, genetic heterogeneity, and environmental factors contributing to the disease manifestation. The relative contribution of each is subject to debate and likely varies between individuals. At one end of the spectrum, disease in some individuals is probably due entirely to environmental influences, yet at the other end is solely under the control of genetic mechanisms. However the majority of cases will most likely be the result of a genetic predisposition with precipitating environmental stressors or modifiers Over the last decade significant progress has been made in identifying genetic risk factors for keratoconus. These genetic risk factors have been identified using multiple approaches including candidate gene studies, linkage analysis, genome‐wide studies and new sequencing technologies. This presentation will summarize how the genes implicated provide clues to the molecular etiology and pathways involved in the pathogenesis of keratoconus.
Twin studies in keratoconus
Authors: LISKOVA P 
Published: August 2014

AbstractGenetic determinants of keratoconus are still largely unknown. Over the last two decades there has been a shift from regarding keratoconus as a monogenic disease with variable expression towards a general consensus that it is most likely to be a multifactorial disorder with multiple genetic and environmental components​ contributing to its development. Twins are useful in assessing the heritability of traits. Discordant monozygotic twin pairs can be used to look for environmental and epigenetic factors. The contribution of twin studies to the understanding of keratoconus genetics will be discussed.
Anti VEGF
Authors: POURNARAS C 
Published: August 2014

AbstractThe diabetic macular edema (DME) related to visual loss, results mainly from changes in the affected blood‐retina barrier. VEGF, originally described as vascular permeability factor, is considered not only as a critical stimulus of retinal neovascularization but also as the primary inducer of increased vascular permeability involved in the formation of diabetic macular edema. Increased levels of VEGF in retina, vitreous and aqueous humor were found in diabetic patients with macular edema (DME). There is increasing evidence that favorable outcomes can be achieved by the use of anti‐vascular endothelial growth factor therapy. Anti‐VEGF therapy combined with laser photocoagulation, is superior to laser photocoagulation for the treatment of moderate‐to‐severe visual impairment caused by DME. Data provided from large phase III clinical trials for ranibizumab showed evidence of visual improvement and favorable safety profile. Further studies for bevacizumab, aflibercept and pegaptanib in DME, although limited, also proved the benefits of using anti‐VEGF therapy instead of laser. As a result, the use of anti‐VEGF therapy as the first line of treatment,is recommended instead of laser photocoagulation in the management of DME.
Current and emerging concepts in neuroprotection
Authors: CORDEIRO M 
Published: August 2014

AbstractThe realisation that lowering IOP is unable to prevent progressive vision loss in all glaucoma patients, has led to investigation of neuroprotection as an alternative or additional treatment option. Neuroprotection has gained renewed interest recently as a therapeutic approach to prevent neuronal degeneration and loss of function in glaucoma, since the publication of the LoGTS study. Although confirmation of neuroprotective effects by other randomized clinical trials is needed, there is now a demonstration of positive non‐IOP dependent effects. Furthermore, it has been proposed as a treatment strategy in other diseases, such as AMD, Alzheimer’s and Parkinson’s Disease. Imaging biomarkers are used in medicine to provide measures that correlate with a clinically significant outcome in disease. By definition they should identify disease early, be easy to assess, have the ability to help predict disease severity and have high enough sensitivity and specificity to be useful. Retinal ganglion cell imaging in glaucoma should fulfil all these criteria. Ideally, a good end‐point in glaucoma would be one that could directly measure RGC dysfunction and disease. Continuing developments in imaging technologies offer great potential in glaucoma. More recently, advances in this field have allowed unprecedented in vivo access to the retinal layers, using many different properties of light to differentiate cellular structures. Over the next few years, advances in therapy & diagnostic methodologies, such as imaging, offer great potential in future for glaucoma.
Straylight for dummies: applications in your daily practice
Authors: VAN DEN BERG T 
Published: August 2014

AbstractIf we consider limitations and defects in the optical apparatus of the eye, two distinct types of defect must be distinguished: (1) errors and irregularities in refraction, and (2) light scattering. Those two effects together determine retinal image quality. Light scattering is recognized from the radiation of light around bright light sources against a dark background, leading to glare. The intensity of this “false” light can be assessed and is called “straylight”. It disturbs not only night driving, but also day time situations, and can be voiced by patients as “hazy vision”, face recognition problems, spatial orientation problems, etc. It is of great importance to realize that these problems often do not coincide with visual acuity loss. So, if visual acuity is good, you may need to assess straylight in order to understand your patient’s complaint. This occurs often in case of early cataract. Studies have shown the existence of a large proportion of non‐acuity cataract that needs treatment all the same. But also in other conditions straylight can be the more important problem. Practical examples and population data will be discussed, including Fuch’s dystrophy, pigmentation defects, IOL deposits and inclusions, etc.
Commercial interest
Aqueous humor cytokine profile of patients with primary or recurrent ocular toxoplasmosis
Authors: THIEME C , PLEYER U , METZNER S , DAMES C , SCHLICKEISER S , DOBNER B , VOLK HD 
Published: August 2014

AbstractPurpose Toxoplasma gondii infection remains the most frequent cause of infectious posterior uveitis and a significant cause of visual impairment worldwide. Still, the immune mechanisms are largely unexplored. The aim of this study is to investigate the cytokine profiles of aqueous humor samples in patients with first or recurrent manifestation of ocular toxoplasmosis and to correlate findings with clinical characteristicsMethods Using the BioRad Multiplex immunoassay, we determined the concentrations of 27 cytokines/chemokines in aqueous humor specimens obtained from 16 patients with active (n=7) or recurrent (n=9) ocular toxoplasmosis. Results were compared to 5 matched control patients without intraocular infectionResults Using the Wilcoxon‐Mann‐Whitney‐Test significant changes could be identified in both groups affected by either initial or recurrent ocular toxoplasmosis compared to controls. Patients with initial manifestation revealed a significant increase (p < 0.05) of IL‐1RA, IL‐7, MIP1a and IP‐10. In addition significant changes in individuals affected by recurrent disease also differed from controls and became significant (p< 0.05) for TNF‐alpha, MIP‐1b and IP‐10. The cytokine/chemokine profiles however did not differ significantly between initial or recurrent ocular toxoplasmosis subgroups.Conclusion Our data suggests that MIP1 and IP‐10 are associated with both primary and recurrent ocular toxoplasmosis. These findings may support the important role of IP‐10 and MIP, as specific chemoattractants for activated T cells in parasitic disorders. In contrast to a recent report we were not able to correlate IL‐5 and VEGF with recurrences of the disease. A larger cohort is recruited to underline the results.
Specifics of viral entry in epidemic keratoconjunctivitis
Authors: RAJAIYA J , YOUSUF MA , MUKHERJEE S , LEE JS , ZHOU X , RAMKE M , LEE JY , CHODOSH J 
Published: August 2014

AbstractCellular entry pathways for viruses dictate the types of immune responses elicited upon infection. Human adenovirus species D type 37 (HAdV‐D37) causes epidemic keratoconjunctivitis (EKC), associated with severe ocular surface inflammation. However, viral entry is known to be cell type and virus specific. To examine basic mechanisms of HAdV‐D37 pathogenesis in EKC, we studied entry of HAdV‐D37 in vivo in our mouse corneal adenovirus keratitis model, and in vitro in cultured human corneal cells. In the mouse model at 1 hour post infection, viruses appeared to be entering cells by macropinocytosis. By 8 hours post infection, viruses formed regular packed intracytoplasmic arrays adjacent to cell nuclei, with minimal capsid uncoating. Therefore, viral entry occurred, but transport of virus to the cell nucleus appeared abortive, possibly explaining the failure of HAdV‐D37 replication in the mouse cornea. In vitro, inhibition of PKCα reduced viral entry and phosphorylation of both Src and caveolin‐1 in lipid raft fractions, suggesting that PKCα activity occurs upstream of both molecules. Phosphorylated PKCα and Src were found in same endosomal fractions and may be physically associated. These results suggest a central role for PKC in HAdV‐D37 entry and regulation of downstream molecules in corneal cells, including caveolin‐1. Interestingly, the small GTPase dynamin II, did not appear necessary for HAdV‐D37 entry into corneal epithelial cells, but was critical for viral entry in corneal fibroblasts.
Eswab® transport media and 16S RNA PCR in the microbiological diagnosis of infectious keratitis
Authors: BAUDONNET R , GARNIER F , ROBERT PY 
Published: August 2014

AbstractPurpose The microbiological diagnosis of infectious keratitis based on a corneal scrapping is necessary in order to adapt the treatment. Our study aimed to determinate if the use of Eswab® transport media and 16S RNA PCR increase the sensitivity of this microbiological diagnosisMethods Retrospective cohort study including all patients who benefited from a corneal scrapping for an infectious keratitis suspicion from June 1, 2007 to June 1, 2011. They were divided into two groups according to the methods of microbiological analysis. In non‐Eswab® (NES) group, four samples per patient were collected, directed to laboratories: bacteriology (direct exam and culture); virology (PCR and culture); mycology and parasitology (direct exam and Acanthamoeba PCR). In the Eswab® (ES) group, three samples per patient were collected. The first one, on Eswab® transport media, was directed to PCR analysis, including 16S RNA, viral and Acanthamoeba research and bacteriological culture. The two others samples were analysed in mycology and parasitology. Infectious gravity factors and the use of antibiotics before corneal scraping, were reported. The main criteria of judgement was the number of patients with a microbiological diagnosisResults 190 patients were included, 84 in the NES group and 106 in the ES group. Infectious keratitis gravity factors (47,6% vs 56,6% p=0,356) and use of antibiotics before the corneal scrapings (23,8% vs 29,2% p=0,5) was not significantly different between two groups. The diagnosis sensibility in the NES group was 36,9% versus 60,4% in the ES group (p=0,002)Conclusion The usage of a transport media such as Eswab® and 16S RNA PCR research on corneal scrapping significantly improves the sensibility of microbiological diagnosis
Genotypes & molecular strategies in albinism
Authors: ARVEILER B , LASSEAUX E , MORICE‐PICARD F 
Published: August 2014

AbstractOculocutaneous albinism (OCA) affects 1/17000 person. It is characterized by hypopigmentation of the skin, hair and eyes. The main handicap in patients is at the ophthalmologic level. There are 6 known OCA genes (TYR, OCA2, TYRP1, SLC45A2, SLC24A5, C10ORF11) (OCA1,2,3,4,6,7 respectively). An OCA5 locus has been localized, but the gene is not known yet. Apart from the OCA types, an X‐linked ocular albinism gene (OA1, GPR143) as well as 17 genes involved in syndromic forms (HPS, CHS, WS, GS) of albinism have been identified. We routinely search for mutations (point mutations, deletions) in the OCA1, 2, 3, 4, 6 ,7, OA1 and HPS1 genes. Our data in more than 400 patients show 36% OCA1, 25% OCA2, 2% OCA3, 11% OCA4, 1.25% OCA6, 0% OCA7, 6% OA1, 1% HPS1. 17.75% of patients remain without a molecular diagnostic either because only one mutation (6%)or no mutation at all (11.75%) was found. This suggests two main alternative hypotheses. First of all the patient may have a hitherto clinically undiagnosed form of syndromic albinism. For this reason, we are now heading towards analyzing all 24 known albinism genes by next generation sequencing. Secondly, it is likely that additional OCA genes remain to be identified.