bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanism of cone cells death in retinitis pigmentosa
Authors: Campochiaro Peter A. 
Published: December 2019

AbstractRetinitis pigmentosa (RP) is a group of diseases in which one of a large number of mutations causes death of rod photoreceptors. After rods die, cone photoreceptors slowly degenerate in a characteristic pattern. Rod cell death causes night blindness, but visual disability and blindness result from cone degeneration and therefore it is critical to determine the mechanisms by which it occurs. The death of rods reduces oxygen consumption resulting high tissue levels of oxygen in the outer retina. The excess oxygen stimulates superoxide radical production by mismatches in the electron transport chain in mitochondria and by stimulation of NADPH oxidase activity in cytoplasm. The high levels of superoxide radicals overwhelm the antioxidant defense system and generate more reactive species including peroxynitrite which is extremely damaging and difficult to detoxify. This results in progressive oxidative damage in cones which contributes to cone cell death and loss of function because drugs or gene transfer that reduce oxidative stress promote cone survival and maintenance of function. Oral administration of N‐acetylcysteine (NAC) has shown good efficacy in mouse models of RP prompting the FIGHT RP1 open label clinical trial, the results of which will be presented.
Contribution of French ophthalmologists
Authors: Soubrane Gisèle 
Published: December 2019

AbstractIn France, ophthalmology was an essential part of medicine in the Gallo‐Roman period ascertained by the oculist stamps. During the Middle‐Ages, couching of the cataractous lens was the only method and this was performed by barber‐surgeons. Ambroise Paré, a military surgeon, considered a pioneer in surgical technics, conceived an artificial eye. His followers opened the way to Daviel who initiated cataract extraction and designed the adapted instruments in the early XVIII th century, the century of surgery. The XVII th century witnessed the development of optics with Descartes. Later, Monoyer and Parinaud designed far and reading scales still used to day. Hauy and Braille took care of the education and created an alphabet for the blind. Meanwhile the introduction of the microscope allowed the description for example of Descemet membrane, Cloquet’s canal, Tenon’s capsule. In the field of retina the introduction of the ophthalmoscope, increased tremendously the level of precision in diagnosis and treatment of ophthalmologic conditions. Giraud Teulon conceived the first binocular indirect ophthalmoscope that will become popular one century later with Schepens. Bonnet‐Blanc ‐Dechaume described the arterio venous communications 6 years before Wyburn‐Mason. After Vienna and Berlin, Paris became a center of excellence in ophthalmology attracting numerous students.
Integrating exome and whole genome analysis with the Human Phenotype Ontology for discovery of new genes in rare eye diseases
Authors: Pontikos Nikolas 
Published: December 2019

AbstractExome and whole genome sequencing have become the preferred approaches for discovering novel causal mutations in monogenic disorders.The effectiveness of these approaches has greatly improved thanks to large datasets of non‐monogenic controls such as Exac and Gnomad, and bioinformatics approaches such as the Variant Effect Predictor.In parallel the detailed encoding of clinical features using the Human Phenotype Ontology (HPO) is greatly helping refine our candidate gene lists by linking patients across databases, mining literature phenotypes from model organisms, and providing improved statistical power through grouping of patients by HPO term. To this aim, we have developed Phenopolis (www.phenopolis.org) for browsing and discovery of gene to phenotype relationships in our large dataset (6000) of HPO annotated exomes and genomes.
Overview of latest clinical advances
Authors: Francesca Cordeiro M. 
Published: December 2019

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. Although confirmation of neuroprotective effects by randomized clinical trials is needed, there was a demonstration of positive non‐IOP dependent effects in the LoGTS study, although recently negative published results of the Memantine study. Furthermore, it has been proposed as a treatment strategy in other ocular diseases, such as AMD. Neuroprotection has been advocated for many years in neurodegeneration. Indeed, the therapies that have been suggested in Alzheimer’s and Parkinson’s Disease are similar to those investigated in ophthalmology. This talk will review the evidence for neuroprotection and its role in glaucoma and application as a practical and future treatment strategy.
Optical coherence tomography – basic optical principles
Authors: Irsch Kristina 
Published: December 2019

AbstractOptical Coherence Tomography (OCT) is an optical analogue to ultrasound imaging. The much higher speed of light compared with sound allows for finer cross‐sectional views of the retina and anterior segment. Since it is extremely difficult to directly detect the shorter “echo” times it takes light to travel from different structures at axial distances within the eye, interferometry is used. Incident light is thus split into two beams, and the beam backscattered from the ocular tissue is then compared (“interfered”) with the beam that has traveled a known time from the reference mirror. Broadband (i.e., low “coherence”) light sources are used, because they produce a wider band of wavelengths, and thereby enable greater sensitivity in comparing the travel time differences of the two beams. In time‐domain OCT, the reference mirror position is altered, so that interference patterns are generated whenever the two beams have traveled almost the same amount of time. In spectral‐domain OCT, the reference mirror position is fixed and the mixed interference patterns are separated via spectral wavelength analysis. This lecture will explain underlying concepts of OCT with a discussion of cutting‐edge technological developments.
Adaptive optics – basic optical principles
Authors: Irsch Kristina 
Published: December 2019

AbstractAdaptive Optics (AO) refers to a technique to compensate for distortions caused by optical aberrations in the media between the camera and the object being imaged. It was originally developed for use in astronomical telescopes to compensate for optical distortions induced by the inhomogeneous earth atmosphere. It has since evolved to become a powerful clinical tool in ophthalmology. In the eye, a “wavefront sensor” (aberrometer) measures the distortion of incoming light induced by inhomogeneities within the cornea and crystalline lens, which is then “undistorted” via reflection by a deformable mirror. AO thus enables imaging of the human retina with unprecedented resolution in vivo, such as revealing individual photoreceptors or the walls of blood vessels. One should note that AO by itself does not provide an image; rather an AO subsystem is incorporated into an existing imaging device. AO subsystems have thus far been successfully integrated into three ophthalmic imaging devices: fundus cameras, scanning laser ophthalmoscopes, and the OCT device. This lecture will introduce the basic principles of AO, illustrate its value with state‐of‐the‐art clinical examples, and discuss potential future applications in ophthalmology.
Ocular thermography in contact lens wearers
Authors: gonzalo carracedo rodriguez juan 
Published: December 2019

AbstractThe infra‐red thermal images have been used in the past for measuring the ocular surface temperature, its main advantage being the non‐invasive means. It is well‐known for its ability to detect the pathological and physiological changes in the eye.There are a few studies about ocular surface temperature and contact lenses. Some authors found that insignificant changes in ocular surface. temperature in soft contact lenses did occur, but other authors described that the pre‐lens tear film in soft lens wearers is cooler than that of the non‐CL‐wearing eye, while the temperature of the post‐lens tear film beneath the CL is higher. Regarding hard and gas permeable corneal contact lenses, the changes are between 0.5–1.5°C compared to the naked eyes. However, gas permeable scleral contact lens seems not to modify the ocular surface temperature despite the presence of the tear film stagnation under the lens.This presentation will navigate in the scientific literature about the usability and applicability of ocular thermography in contact lens wearers.
IOL calculation concepts
Authors: Langenbucher Achim 
Published: December 2019

AbstractThe first intraocular lenses implanted resampled the shape of the natural lens and resulted in high postoperative myopia. First attempts to preoperatively calculate the intraocular lens (IOL) power by vergence formulas were presented by Fjodorov in 1967. Other authors soon followed presenting numerous attempts to estimate the required IOL power. While most of the calculation schemes nowadays are based on the vergence formula, there were also empirical approaches such as the SRK and SRK‐II formulas. Beside different interpretation of corneal power from the measured radii of curvature and several offset values, the main difference between formulas is in the estimation of the effective lens position (reference plane of the thin lens in the pseudophakic eye) (ELP): We will present various approaches for calculating IOL power and discuss differences between formulas as well as the pros and cons of these different concepts.
Expression of VEGFA‐regulating miRNAs and mortality in wet AMD
Authors: Blasiak Janusz 
Published: December 2019

AbstractMicro RNAs (miRNAs) regulate gene expression and hundreds of them act in retinal pigment epithelium (RPE), whose degeneration is critical in age‐related macular degeneration (AMD). Repeated injections with anti‐VEGFA (vascular endothelial growth factor A) is the only remedy in wet AMD. We investigated the correlation between the expression of 18 miRNAs involved in the regulation of the VEGFA gene in serum of 76 wet AMD patients and 70 controls. Pharmacogenetic efficacy of anti‐VEGFA treatment was evaluated by the number of injections monitored up to 12 years. In addition, we compared the relative number of deaths in AMD patient and control groups. We observed a decreased expression of miR‐34‐5p, miR‐126‐3p, miR‐145‐5p and miR‐205‐5p in wet AMD patients as compared with controls. These miRNAs are involved in the regulation of angiogenesis, cytoprotection and protein clearance. No miRNA was significantly correlated with the treatment outcome. Wet AMD patients had greater mortality than controls and their survival was inversely associated with the number of anti‐VEGFA injections per year. No association between miRNA expression and mortality was observed. Our study supports the importance of and the need for further research on the role of miRNA regulation in AMD pathogenesis.
Dealing with the complications of uveitis
Authors: Tranos Paris 
Published: December 2019

AbstractUveitis may exist as a clinical manifestation of an underlying systemic disease or may represent an idiopathic entity, sometimes with a very characteristic pattern. A plethora of ocular complications including cataract, glaucoma, macular edema and retinal detachment are associated with intermediate uveitis, posterior uveitis, or panuveitis and may occur during the acute, active phase or even when remission of the inflammatory process has been achieved. Early diagnosis and optimal treatment initiatives remain imperative to reduce the ocular complication–related burden and attain better functional and anatomical outcomes.
Comparison of in vitro assays to study the effectiveness of antiparasitics against Acanthamoeba castellanii trophozoites and cysts
Authors: Shi Lei , Stachon Tanja , Latta Lorenz , Ibrahem Elhawy Mohamed , Orosz Erika , Kiderlen Albrecht F. , Seitz Berthold , Bischoff Marukus , Szentmáry Nóra 
Published: December 2019

AbstractPurposeTo compare LDH release assay, trypan blue and fluorescent stainings and non‐nutrient Escherichia coli (E. coli) plate assay in determining treatment efficacy of antiamoebic‐agents against Acanthamoeba castellanii trophozoites and cysts, in‐vitro.MethodsA. castellanii strain 1BU‐trophozoites/cysts were challenged with the antiamoebic‐agents 0.02% polyhexamethylen‐biguanid (PHMB), 0.1% propamidin‐isethionate (PD) and 0.0065% miltefosine (MF). Efficacies of the drugs were determined by LDH‐release and trypan blue assays. The fluorescent dyes Hoechst 33343, calcein‐AM, and ethidium‐homodimer‐1 were tested for their abilities to differentiate between viable and dead 1BU‐trophozoites/cysts following treatment, a non‐nutrient agar E. coli plate assay was applied to monitor the outgrowth of 1BU‐trophozoites/cysts challenged with antiamoebic‐agents.ResultsAll three antiamoebic‐agents induced a significant LDH‐release from trophozoites, when compared to controls (p < 0.0001). There was a negligible trypan blue, Hoechst33342, calcein‐AM and ethidium‐homodimer‐1 staining in untreated 1BU‐throphozoites and cysts. Percentage of trypan blue positive trophozoites/cysts was 59.3 ± 1.5% /100% after challenge with PHMB, 100%/99.3 ± 0.5% upon PD treatment, and 95.6 ± 2.5%/77.6 ± 5.1% when using MF. Hoechst 33342 stained 100%/100%, ethidium‐homodimer‐1 100%/100%, calcein‐AM 75.33 ± 4.04%/60.67 ± 3.51% of PHMB treated trophozoites/cysts. Hoechst 33342 and ethidium‐homodimer‐1 were 100%/100%, calcein‐AM 9.67 ± 2.52%/36.67 ± 4.51% positive in PD‐treated trophozoites/cysts. MF treatment resulted in 100%/100% Hoechst 33342 and ethidium‐homodimer‐1 positive trophozoites/cysts, while none of them became positive for calcein‐AM. On non‐nutrient agar E. coli plates, in controls and MF treated 1BU trophozoites/cysts, new trophozoites appeared within 24 hr, and encystment occured after 5 weeks of cultivation. In PHMB and PD treated 1BU‐throphozoites/cysts, irregularly shaped, smaller trophozoites appeared after 72 hr, which failed to form new cysts within 5 weeks.ConclusionsNone of the enzymatic‐ and dye‐based viability assays tested here generated survival rates for trophozoites/cysts that were comparable with those yielded with the non‐nutrient agar E. coli plate assay, suggesting that the culture‐based assay is the best method to study the treatment efficacy of drugs against Acanthamoeba.
Comparison of Anterior Segment Parameters Between Phakic and Pseudophakic Eyes of Subjects with Emmetropia and Degenerative Myopia
Authors: Demir Mehmet , Akpolat Cetin , Arslan Gurcan Dogukan , Sendul Yekta 
Published: December 2019

AbstractPurposeTo compare and assess anterior segment measurements including corneal endothelial parameters in phakic and pseudophakic patients with degenerative myopia and emmetropic participants.MethodsThe individuals were divided into two main groups of Group 1 (control group) and Group 2 (study group). Emmetropic, mild myopic and/or hypermetropic patients were enrolled in Group 1. Degenerative myopic patients were enrolled in Group 2. Group 1 and 2 were composed of phakic (Group 1A, Group 2A) and pseudophakic (Group 1B, Group 2B) eyes. Corneal endothelial cell density (CD), the coefficient of variation of cell size (CV), hexagonality (HEX) and central corneal thickness (CCT) were of the parameters measured by the specular microscope. Anterior chamber depth (ACD), white to white (WTW) diameter and axial length (AXL) were the parameters measured by optical biometer.ResultsThe mean ACD was 3.45 ± 0.55 mm and 3.74 ± 0.61 mm (p = 0.005), and the mean AXL was 23.3 ± 0.9 mm and 28.6 ± 5.3 mm (p <0.001) in the control and study group, respectively. Mean BCVA values were worse and mean SE values were higher in degenerative myopic eyes than in emmetropic eyes of both phakic and pseudophakic subjects. Mean ACD was higher in degenerative myopia. Mean K2 was different between Group 1B and Group 2B (p=0.003).ConclusionsDegenerative myopia has high SE, ACD and AXL values. However, most of the specular microscope measurements did not show a significant difference in degenerative myopia.
Corneal asphericity differences between nasal‐temporal and superior‐inferior quadrants in myopic Korean children
Authors: Chun Heejeong , Ha Minji , Na Kyungsun 
Published: December 2019

AbstractPurposeCorneal asphericity (Q‐value) represents the difference in curvature from center to periphery of the cornea. This study evaluated horizontal and vertical asymmetry in corneal asphericity in myopic children and its relationship with various ocular parameters.MethodsThis retrospective study included 22 eyes in 11 myopic Korean children. Corneal parameters, such as corneal asphericity and thickness, apical radius of curvature, and high order aberrations including total RMS, spherical aberration, coma, and trefoil were analyzed by Pentacam. Axial lengths and anterior chamber depths (ACD) were measured by IOL master. From these values, characteristics of corneal asphericity differences between nasal‐temporal and superior‐inferior quadrants in myopic children and their relationship with other ocular parameters were evaluated.ResultsThe mean Q‐value (8 mm) was −0.298 ± 0.093, representing a prolate corneal shape. The mean superior‐inferior Q‐value differences (8 mm) was 0.249 ± 0.216, which was greater than the mean nasal‐temporal Q‐value differences (8 mm) measured as 0.130 ± 0.141. The mean Q‐value (8 mm) had a positive correlation with ACD (p = 0.019), whereas Q‐values in each quadrant (8 mm) showed no significant relationship with corneal thickness in each corresponding quadrants. The nasal‐temporal Q‐value differences (8 mm) showed a positive relationship with total RMS (p = 0.03) and a negative relationship with oblique trefoil (p = 0.045), and the superior‐inferior Q‐value differences (8mm) showed a negative relationship with vertical trefoil (p = 0.042).ConclusionsThe results of the study showed a variation of nasal‐temporal and superior‐inferior Q‐value differences, and the relationship between corneal shape and other ocular dimensions in myopic Korean children. A single value of asphericity of anterior cornea could not precisely reflect corneal structure. Further study with large data set is merited to ascertain the epidemiologic data of Asian ethnicity.
Probiotic bacteria Escherichia coli Nissle decrease the severity of intraocular inflammation in experimental autoimmune uveitis
Authors: Dusek Otakar , Svozilkova Petra , Klimova Aneta , Brichova Michaela , Kverka Miloslav , Tlaskalova‐Hogenova Helena , Fajstova Alena , Coufal Stepan , Hrncir Tomas , Kucera Tomas , Heissigerova Jarmila 
Published: December 2019

AbstractPurposeThe purpose of the project was to test the influence of probiotic bacteria Escherichia coli Nissle (EcN) on severity of intraocular inflammation in experimental autoimmune uveitis (EAU).MethodsEAU was induced in C57BL/6J mice by interphotoreceptor retinoid binding protein in complete Freund´s adjuvant and pertussis toxin. The grade of uveitis (0–4) was assessed clinically (21st and 27th day) by using otoscope connected to camera and histologically (28th day) on hematoxylin and eosin stained tissues. Probiotic bacteria EcN were administered orally three times a week and saline solution was administered to control group. Different regimens of administration were tested as follows: administration throughout the experiment (47 eyes), prophylactically (26 eyes) and therapeutically (24 eyes). Mesenteric and cervical lymph nodes were collected at the end of experiment for flow cytometry analysis of lymphocyte populations (Treg, Th17, ILC3) and intracellular cytokines (IFNγ, TNFα, IL‐17).ResultsProbiotics significantly reduced the severity of uveitis compared to the control group in all three regimens by clinical evaluation i.e. throughout the experiment (p = 0.0003), prophylactically (p = 0.0015) and therapeutically (p = 0.02) and by histological evaluation throughout the experiment (p = 0.0002) and prophylactically (p = 0.0017). There was no significant difference in the lymphocyte population counts and cytokines production between groups.ConclusionsOrally administered probiotic bacteria EcN successfully prevented or reduced the severity of EAU in mice. This may have valuable implications for the control of sight‐threatening uveitis in patients.Supported by Ministry of Health of the Czech Republic (grant 17‐31248A) and Charles University Institutional Program SVV 260367.
Influence of coenzyme Q10 on ocular surface mıcrobıata
Authors: Kocaturk Tolga , Telli Murat , Korkmazgil Berna , Bilgen Mehmet 
Published: December 2019

AbstractPurposeTo evaluate the effects of Coenzyme Q10 on the proliferation of the most common ocular surface bacteria; S. aureus, P. aeruginosa and fungus; C. albicans.MethodsExperiments were performed in‐vitro with total 15 glass tubes of each filled with 1.5 mL. of fluid media were prepared. The tubes were then divided equally into three groups to culture the bacteria S. aureus, P. aeruginosa and fungus C. albicans. In a set of 5 tubes, colony of each microorganism was thus produced. In each group, Tube (numbered 0) was established as a control. The remaining Tubes 1–4 were respectively added with 1–4 drops of CoQ10 containing eye drops. The tubes were then evaluated at 0, 1, 2, 4, 5 and 24 hr. The proliferation of microorganism in a liquid medium resulted in turbidity from which microbial concentration was estimated using McFarland barium sulphate turbidity standard. Measurements were performed on the spectrophotometer as McFarland standard and interpreted through the changes in reproduction. For each group, the estimates of the average numbers of the corresponding microorganisms subjected to the four different strengths of CoQ10 were recorded and statistically compared to those in the control group.ResultsIn all the groups, the concentrations of the microorganisms (S. aureus, P. aeruginosa and C. albicans) increased with time. However, exposure to CoQ10 containing eye drops did not significantly alter the microorganismal growth as the measurements from the CoQ10‐instilled tubes remained comparable to those of the controls.ConclusionCoQ10 under in‐vitro conditions did not induce proliferation of S. aureus, P. aeruginosa and C. albicans.
Long‐term clinical courseafter vitrectomy for breakthrough vitreous hemorrhage secondary to neovascular age‐related macular degeneration
Authors: Kim Chulgu 
Published: December 2019

AbstractPurposeTo investigate the long‐term clinical course after vitrectomy for breakthrough vitreous hemorrhage secondary to neovascular age‐related macular degeneration (AMD).MethodsThis retrospective study included 45 eyes that underwent vitrectomy due to breakthrough vitreous hemorrhage secondary to neovascular AMD. The patients were divided into two groups: typical neovascular AMD group and polypoidal choroidal vasculopathy (PCV) group. Within each group, the status of the eye within 6 months after the surgery and that at the final follow‐up was identified. The visual acuity at the final visit was additionally compared between the two groups.ResultsThe patients were followed up for a mean period of 39.9 ± 19.4 months after the surgery. In the typical neovascular AMD group (n = 17), re‐bleeding requiring vitrectomy was noted in four eyes and extensive scar formation was noted in six eyes within 6 months after the surgery. At the final visit, treatment was discontinued due to poor visual outcome in 12 eyes. In the PCV group (n = 28), re‐bleeding requiring vitrectomy was noted in one eye, and extensive scar formation was noted in four eyes within 6 months after the surgery. At the final visit, treatment was discontinued in eight eyes. The visual acuity at the final visit was significantly better in the PCV group (p = 0.003).ConclusionsThe long‐term clinical course after vitrectomy for breakthrough vitreous hemorrhage was markedly different between typical neovascular AMD and PCV, showing significantly better long‐term visual outcomes in PCV.