bluuebunny/crossref_metadata_2025 huggingface dataset:
Visual acuity thresholds associated with activity limitations in the elderly. The POLA study
Authors: DAIEN V , PERES K , VILLAIN M , COLVEZ A , CARRIERE I , DELCOURT C
Published: November 2013

Purpose Activity limitations, which induce loss of autonomy in the elderly, are a major public health problem. We investigated the associations between objectively determined visual impairments and activity limitations, and assessed the visual acuity thresholds associated with these restrictions.

Methods The study sample consisted of 1887 people aged 63 years and over from a population‐based cohort. Visual impairment was defined according to the WHO definition. Multivariate logistic regressions were used to estimate the associations between vision and Instrumental Activities of Daily Living (IADL) limitations. Using receiver‐operating characteristic (ROC) curves, we identified visual acuity thresholds that maximized the Youden index ([Sensitivity+Specificity]‐1) for predicting IADL limitations.

Results After adjustment for potential confounders, moderate to severe visual impairment and mild visual impairment were strongly associated with IADL limitations(odds ratio [OR]=3.49; 95% confidence interval [CI]=1.93, 6.32 and OR=1.77; 95% CI=1.07, 2.91, respectively). Visual acuity was a strong predictor of IADL limitations, with an area under the ROC curve of 0.72 (95% CI=0.68, 0.76). The best discrimination between subjects with or without IADL limitations (global, physical, cognitive) was obtained for visual acuities around 20/40‐20/50.

Conclusion This study confirms major increased risk for IADL limitations in subjects with moderate to severe visual impairment. In addition, it suggests that milder visual impairments (in particular below 20/40) may also be related to an increased risk for IADL limitations and should be considered for early medical intervention, before the decline of the subjects’ autonomy.
Functional characterization of retinitis pigmentosa causing RPGR mutations
Authors: SHU X , PATNAIK S , CRAFT J , MCCULLOCH D
Published: November 2013

Purpose Retinitis pigmentosa (RP) is a progressive outer retinal dystrophy, affecting 1/3500 individuals in most populations. X‐linked RP (XLRP) is one of the most severe forms of human retinal degeneration, as determined by age‐of‐onset and progression. Mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene, responsible for the major subtype of XLRP, are the most common single cause of RP, accounting for 6‐20% of all cases. We aim to investigate the functional role of RPGR mutations in the pathogenesis of XLRP.

Methods Different RP‐causing RPGR mutations were cloned into pCEP‐4 expression vector and transfected into retinal pigment epithelium (RPE) 1 and IMCD3 cell lines. RPGR expression was detected by immunocytochemistry and western blotting. The pathological effects caused by RPGR mutations were characterized by immnocytochemistry.

Results The average length of cilia in RPE1 cells with over‐expression of mutant RPGR are around 50‐60% shorter compared to that in cells with over‐expression of wild type RPGR. Cells with over‐expression of RPGR mutant proteins exhibited stronger actin filaments. The frameshift RPGR mutations also cause aggregations in IMCD3 cell lines indicating that the mutant proteins are misfolded which may cause toxicity.

Conclusion Mutant RPGR proteins have functional role in cilia defect through regulating actin remodelling,
Modern Trabeculectomy: Technique, and results from a UK muticentre study
Authors: KIRWAN JF , LOCKWOOD A , MCNAUGHT AI , MACLEOD A , SHAH P , KING AJ , BROADWAY DC , AGRAWAL P
Published: November 2013

Efficacy and safety of current trabeculectomy surgery Methods: 428 patients with OAG and no previous glaucoma surgery from 9 units were evaluated. All cases had 2 yr minimum follow up. Main outcomes: IOP, VA, complications and interventions. Reoperation for glaucoma (except needling and resuturing) and loss of light perception were classified as failures. Results: Antifibrotics were used in 400 (93%) cases; MMC in 271 (63%), 129 had 5‐FU (30%). At 2 years, IOP (mean ± SD) was 12.3 ± 4.3 mmHg, 370 (86%) had IOP ≤21 mmHg without medication; 405 (95%) achieved an IOP ≤ 21 mmHg overall. IOP ≤18 mm Hg was achieved by 352 (82%) without treatment and 373 (87%) overall. By TVT criteria: 310/365 (85%) had complete success at 2 yr and 335/365 (92%) achieved qualified success. Postoperative treatments: suture manipulation 43%, resuturing 5.1%, bleb needling 16%, postop 5FU 27% and cataract extraction in 31%. Visual loss of more than two lines occurred in 24 (5.6%). 31 (7.2%) had late hypotony (IOP <6 mmHg). 2 patients (0.5%) developed blebitis. One patient had endophthalmitis at 3 wks (0.2%). We show good trabeculectomy outcomes with low rates of complications can be achieved but intensive postoperative care is required.
In vivo integrity of intra‐corneal bioengineered discs in rabbit models
Authors: RAFAT M , LAGALI N , KOULIKOVSKA M , GRIFFITH M , FAGERHOLM P
Published: November 2013

Background: We have previously reported the successful integration and safety of bioengineered materials as corneal substitutes in human models. Despite the promising results as corneal implants, more elastic and robust materials are required for use as thin intra‐corneal lenses to withstand surgical manipulation for corrective surgery and improved vision. Most of the existing corneal inlays are made of synthetic materials. Here we describe the potential of bioengineerd materials for vision correction. Objectives: to develop bioengineered materials as inlays within the corneal tissue as well as evaluating the in vivo integrity and integration of the materials in rabbit models. Methods: Bioengineered inlays were prepared from collagen and tested for their physical and biological propertis. A femtosecond laser was used to cut 100 mircon thick discs of mid‐stromal tissue from corneas of 20 rabbits and replaced with bioengineered inlays. Results: The new materials demonstrated improved mechanical properties while maintaining their clarity and biocompatibility. The bioengineered inlays retained their shapes, thickness, and clarity 8 weeks post‐surgery in rabbits.

Commercial interest
The basics of femtosecond laser cataract surgery
Authors: NAGY Z
Published: November 2013

Femtosecond lasers have been used for corneal flaps for years. Recently the problems of beam delivery through the ocular optic media has been solved. Precise incisions can be performed within the crystalline lens (fragmentation or liquefaction), on the anterior capsule and possible on the posterior capsule as well (capsulotomy) and in the cornea (customised geometry, size and position of the wounds). During the lecture the basics of femtolaser catarct surgery will be shown.
Endothelial graft precutting from the epithelial and endothelial side with the femtosecond laser, on cornea stored in a new corneal bioreactor
Authors: BERNARD A , MAUCLAIR C , BAUBEAU E , GRANIER J , EGAUD G , HE Z , CAMPOLMI N , PISELLI S , FOREST F , PEOC'H M , DUMOLLARD JM , THURET G , GAIN P
Published: November 2013

Purpose To compare femtosecond laser endothelial graft precut from epithelial and endothelial side, on corneas stored in a new corneal bioreactor

Methods Human corneas unsuitable for transplantation for serological reasons and procured by the Auvergne‐Loire eye bank (Saint Etienne, France) were used after informed consent of the relatives, as authorized by French bioethics laws. Femtosecond laser lamellar cuts were realized on corneas stored in a new corneal bioreactor, patented by our laboratory, designed to maintain a constant endothelial pressure and to permit an epithelial aplanation without opening the device. Lamellar cuts of several thickness were realized with corneal epithelium or corneal endothelium side up, but always with epithelial aplanation. OCT images (Casia SS1000, Tome) were realized in the bioreactor before and after each cut. Endothelial viability was determined by using a triple Hoechst/Ethidium/Calcein labeling (HEC, IOVS Pipparelli 2011) coupled with image analysis of the whole endothelial surface immediately after the cut. Surface roughness was assessed by scanning electron microscopy

Results This study demonstrates the possibility to realise femtoseconde laser endothelial graft precut directly in a dedicated storage device. First results of endothelial viability in function of lamellar graft thickness and lamellar cut side will be presented as well as surface roughness

Conclusion Capacity to realize femtosecond laser endothelial graft precut directly in a storage device could improve the quality and security of delivered lamellar grafts
Adeno‐associated viral vector serotypes for gene transfer to corneal endothelial cells
Authors: FUCHSLUGER T , MUELLER C , DANA R
Published: November 2013

Purpose The aim of this study was to determine the efficacy and efficiency of the non‐pathogenic recombinant adeno‐associated viral vectors (rAAV) for gene transfer to EC. Therefore, different rAAV pseudotypes were compared to assess the expression and kinetic patterns of a reporter gene (GFP).

Methods A comparison of GFP expression and kinetics after EC transduction using a AAV 2/1, 2/2, 2/5, 2/8, 2/9, 2/10 was performed on both murine EC (Balb/C) and human EC (corneas, cell line and primary cells). In addition, the effects of different vector concentrations (3x10^3/10^4, 10^5, 10^6, 10^7, 10^8IU/µl) were investigated. Analyses were performed using laser scanning microscopy and flow cytometry.

Results Significant differences between human and murine EC as well as primary and immortalized EC were detected. Murine corneal EC transduced with AAV2/2, 2/5 and 2/9 resulted in considerable protein expression, AAV 2/5 did not show considerable expression in human corneas. A slow onset of GFP expression both in immortalized and primary EC was detected, leading to peak and stable expression around 2‐3 weeks. Peak expression was reached earlier in primary EC and immortalized murine EC compared to immortalized human EC. The overall plateau of expression was highest in primary EC (~80%).

Conclusion Pseudotypes of recombinant AAV alter in their tropism and transduction efficiency between murine and human corneas. In general high levels of gene expression can be obtained with several of these pseudotypes. Characteristic slow‐onset kinetics of protein expression have to be taken into account when applying AAVs in translational applications, e.g. in corneal storage in eye banks.
Iron antagonism of DICER1 promotes NLRP3 inflammasome priming due to enhanced Alu RNA stability
Authors: GELFAND B , KIM Y , YASUMA T , LI S , FOWLER B , KLEINMAN M , AMABTI J
Published: November 2013

Purpose Excessive free iron induces retinal toxicity in several human diseases and has been linked to age‐related macular degeneration. Iron toxicity is widely attributed to its ability to catalyze hydroxyl radical formation through Fenton’s reaction. Iron was recently described as an inhibitor of canonical DICER1 enzymatic activity through sequestration of the cofactor poly(C)‐binding protein 2 (PCBP2). We sought to determine whether iron similarly impaired non‐canonical DICER1 activity to clear cytotoxic Alu RNA in the retinal pigemented epithelium.

Methods Iron overload was induced in human ARPE‐19 cells by supplementing culture media with ferric ammonium citrate for 72 hours and in wild‐type mice by subretinal injection. Alu, B1 and B2 RNA abundance was measured by northern blotting. Alu RNA/DICER1/PCBP2 binding was assessed by immunoprecipitation, western blotting and LC‐MS. Alu RNA cleavage efficiency was evaluated using synthetic in vitro transcribed Alu RNA and recombinant human DICER1 and PCBP2. Inflammasome priming was assessed by quantifying NLRP3 mRNA via qRT‐PCR.

Results Iron overload in cells and mouse retina induces robust accumulation of Alu transcripts as well as the rodent homologs B1 and B2 RNAs. Iron overload impairs Alu RNA clearance by RPE cells, independently of DICER1 mRNA abundance. Alu RNA binds to the iron sensitive co‐factor PCBP2, which enhances DICER1‐mediated Alu RNA cleavage. Iron overload or siRNAs targeting PCBP2 prime the NRLP3 inflammasome, which can be prevented by antisense‐mediated Alu RNA antagonism.

Conclusion These data suggest that Alu RNA induced inflammasome signaling could contribute to retinal iron toxicity in addition catalytic free radical generation.
Retinal pigment epithelium cell‐derived microparticles mediate oxidative stress‐induced retinal cells dysfunction
Authors: TAHIRI H , YANG C , DUHAMEL F , CHEMTOB S , HARDY P
Published: November 2013

Purpose Age‐related macular degeneration (AMD) represents the leading cause of vision loss in the elderly. The cumulative oxidative injury induces retinal pigment epithelium (RPE) membrane microparticles production, RPE cell death and cellular senescence. The RPE blebs are implicated in the formation of sub‐retinal deposit. Nonetheless, the pathophysiological roles of RPE microparticles (RMPs) remain largely unexplored. This study was designed to investigate whether RMPs participate in the retinal cells dysfunction.

Methods RMPs and fluorescent DiI‐labelled RMPs were isolated from cultured ARPE‐19 cells under oxidative stress. RMPs‐treated RPE cells were subjected to WST‐1, cellular senescent, apoptotic assay and FACS cell cycle analysis respectively. The antibody against CD36 was used in uptake experiment to determine the involvement of scavenger receptor CD36.

Results Our study revealed that uptake of RMPs by RPE cells is time‐dependent, and this process is partially dependent on CD36 evidenced by an approximately 50% decrease of RMPs uptake caused by CD36 antibody treatment. In addition, RMPs significantly reduced RPE cell viability in a dose‐dependent manner. RMPs in a concentration of 5% µg/ml significantly induced RPE cell‐cycle arrest at G0/G1 phase. RMPs‐treated cells exhibited a 19% increase in G0/G1 phase, with associated increases of the senescence‐associated β‐galactosidase activity.

Conclusion We demonstrated for the first time that RPE cells uptake microparticles derived from RPE cells under oxidative stress. These findings strongly suggest that RMPs function as mediators to exacerbate the oxidative damages to RPE cells, and indicate a pathological role of RMPs in AMD.
Plasma gangliosides and age‐related macular degeneration
Authors: DOSSARPS D , MASSON EA , BERDEAUX O , BRON A , CREUZOT‐GARCHER C , BRETILLON L
Published: November 2013

Purpose Age‐related macular degeneration (AMD) is a multifactorial and polygenic disease and is the main cause of vision loss in developed countries after 50 years old. Indeed, dry AMD leads to progressive retinal atrophy and exsudative AMD induces a rapid alteration of the macula through neovascularisation. Gangliosides (GG) make a wide and heterogeneous family of sialic‐acid‐containing glycosphingolipids, composed of a sugar chain branched on a ceramide. They are major components of cellular membranes and are particularly abundant in the brain and nervous tissue, including retina. They are also found circulating in the plasma. GG are known for their neuroprotective properties in the nervous system and retina. The present study aimed to determine whether plasma GG could represent biomarkers of AMD.

Methods The study included 90 subjects divided into 3 groups: control, dry AMD and exsudative AMD. For each subject, plasma GG were extracted, purified and analyzed by liquid chromatography coupled to mass spectrometry.

Results GM3 appeared to be by far the major GG of human plasma. Small amounts of GD3, GM2, GD1a and GD1b could also be detected, but no specific species could be identified in the plasma of AMD patients. Fifteen molecular species of GM3 were identified accounting for the variability in the ceramide moiety of the GG molecule. Analyses revealed no significant differences in the proportion of the different GM3 species between control, dry and exsudative AMD patient groups.

Conclusion Although GG are important for retina’s structure and function, it seems they cannot be used as circulating markers of the retinal damages occurring during the course of AMD.
Inflammatory cytokines decrease viability and alter ganglioside profile in retinal pigment epithelium cells
Authors: MASSON EA , DOSSARPS D , BERDEAUX O , BRON A , CREUZOT‐GARCHER C , BRETILLON L
Published: November 2013

Purpose Early stages of Age related Macular Degeneration (AMD) are characterized by dysfunction and degeneration of the retinal pigment epithelium (RPE) cells, which participate in the death of the overlying photoreceptors ultimately leading to loss of vision. Gangliosides (GG) make a wide and heterogeneous family of sialic‐acid‐containing glycosphingolipids, composed of a sugar chain branched on a ceramide. They are major components of cellular membranes, particularly abundant in the brain and nervous tissue, including retina. While their developmental and neuroprotective actions have been demonstrated, their precise role in retina’s function and its pathologies is still poorly understood. The present study aimed to investigate the role of GG in the response of RPE cells to inflammation, which is known as one of the pathophysiological features of AMD.

Methods Cultured human RPE cells (ARPE19) were exposed to an inflammatory cytokine mixture (ICM): TNF‐α, IL‐1β and IFN‐g for 72 hours. Cell viability was assessed and GG were analyzed by Liquid Chromatography coupled with tandem mass spectrometry.

Results ICM had deleterious effects on ARPE19 viability: cell number decreased by half between control and treated conditions. GM3 appeared to be the main GG class present in ARPE19 cells. Interestingly, ICM exposure was associated with modifications in the GM3 profile: relative amounts d18:1/16:0 species increased whereas those of d18:1/24:1 species decreased.

Conclusion Our observations suggest that GG might be implicated in ARPE19 cell response to inflammatory cytokines, although the precise biological role of the change in fatty acid profile of GM3 still needs to be clarified.
Blue light toxic action spectrum on A2E‐loaded RPE cells in sunlight normalized conditions
Authors: BIGOT K , BARRAU C , GONDOUIN P , VILLETTE T , SAHEL JA , PICAUD S
Published: November 2013

Purpose Sunlight exposure is supposed to induce cumulative damage to the retina in retinal pathologies, such as AMD. The high energy visible spectrum between 380 nm and 500 nm (blue light) is incriminated. The goal of this study was to identify the spectrum of retinal toxicity induced by sunlight in physiological irradiance conditions.

Methods RPE cells incubated for 6 hours with 0, 12.5, 20 and 40 µM of A2E were exposed for 18 hours to 10 nm illumination bands with the first band centered at 390 nm and going up to 520 nm. Light irradiances were normalized with respect to the natural sunlight reaching the retina after filtering by the eye ocular media. Six hours after light exposure, cell viability, necrosis and caspase‐3/7 activity were assessed using the Apotox‐Glo Triplex Assay.

Results A2E‐loaded RPE cells presented fluorescent bodies within the cytoplasm with a similar spectrum to that of A2E. Exposure to the 10 nm illumination bands induced morphological changes associated to a loss in cell viability. Light toxicity was dependant of A2E concentration and was higher in the blue spectral range with maxima in a specific 30 to 40 nm bandwidth. In addition, caspase‐3/7 activity, indicative of cell apoptosis, was highly induced by the same narrow range whereas necrosis was not significantly different to that of cells maintained in darkness.

Conclusion We described for the first time the precise spectrum of light toxicity in physiological irradiance conditions on an in vitro model of AMD. The 415‐455 nm narrow spectral range generated the greatest phototoxic risk to RPE cells. This provides new information for designing selective protective filters, without disrupting visual and non‐visual functions.
Chicken peptidylarginine deiminase type I and III are constitutively expressed in the retinal neuron
Authors: SHIMIZU A , HONDA T , KOJIMA T , KOHSAKA T , TAKAHARA H
Published: November 2013

Purpose Peptidylarginine deiminase (PAD) is a post‐translational modification enzyme that catalyzes the conversion of protein‐bound arginine residues to citrulline residues in the presence of calcium ion. PAD genes are distributed generally throughout vertebrates. In chickens, three PAD genes have been identified and are orthologous to the mammalian genes encoding PAD1, PAD2 and PAD3, respectively. The expression levels and tissue/cellar location of each PAD under normal physiological conditions have not been elucidated as yet.

Methods cPAD1 or cPAD3 specific antibodies were prepared from rabbits immunized with a synthetic peptide and used for western blot analyses and immunohistochemistry assays. To determine the intracellular localization of chicken PADs in retina cells, immunoelectron microscopy was also carried out. Whether or not the deiminated proteins were produced in retinal tissues was also examined by immunohistochemistry using an anti‐modified citrulline detection method.

Results We found that both cPAD1 and cPAD3 are expressed in the chicken retina. cPAD1 was localized in the inner nuclear layer (INL) whereas cPAD3 was localized in the outer photoreceptor (OP). cPAD3 was present at especially high levels of detection in the lamella structure. Deiminated proteins were also detected in the INL and OP, suggesting that cPAD1 and cPAD3 function in the chicken retina under normal physiological conditions.

Conclusion Our findings suggest that chicken PAD1 and PAD3 play a homeostatic role in the chicken retina in governing sight.
A drug‐induced central retinal vein occlusion
Authors: BAUDOT A , TRECHOT F , BATTA B , ANGIOI K
Published: November 2013

Purpose To report a case of central retinal vein occlusion probably caused by tranexamic acid medication.

Methods A 45‐year‐old woman consulted in our emergency room because of a visual field defect in a her left eye without visual loss. Her past medical history revealed metrorrhagias treated by tranexamic acid and no cardiovascular disease. Visual acuity was 20/20 in both eyes. Slit‐lamp examination was normal in both eyes and fundus examination showed peri‐papillary haemorrhages LE. Two days later she complained of sudden visual loss LE. Visual acuity of her left eye was limited to light perception. Fundus examination revealed many haemorrhages, macular edema, and papillary edema. Fluorescein angiography showed central retinal vein occlusion associated with a cilioretinal occlusion. General and biological examinations revealed no abnormalities. Systemic disorders were excluded. Therefore we concluded to a iatrogenic pathology.

Results In our patient after excluding systemic disorders potentially responsible for this ocular pathology we suspected a iatrogenic cause. Tranexamic acid is a classical treatment for haemorrhages especially in case of metrorrhagias. It allows haemostasis thanks to an antifibrinolytic action due to plasminogen inhibition. A few cases of vein and arterial occlusions caused by tranexamic acid treatment have been reported in literature.

Conclusion In a young patient without systemic disorder presenting with a retinal vascular occlusion we must always keep in mind a drug‐induced pathology.
Serum concentrations of infliximab in patients with Behçet's disease
Authors: TAGUCHI C , INOUE R , YAMAKAWA R
Published: November 2013

Purpose We investigated the relationship between the serum concentrations of infliximab (IFX), an anti‐tumor necrosis factor‐alpha monoclonal antibody, and its therapeutic effect in patients with Behçet's disease (BD) who were receiving IFX therapy.

Methods Nine BD patients (7 males and 2 females) with uveitis who were receiving IFX therapy for 1 years or longer were included in this study. IFX (5‐6 mg/kg) was administered at weeks 0, 2, and 6 and thereafter every 8 weeks. After informed consent was obtained, peripheral blood samples were collected before the IFX infusion. The serum concentrations of IFX were measured by enzyme‐linked immunosorbent assay.

Results In the 6 patients who did not develop any uveitis attacks, the mean serum concentration of IFX was 3.6‐13.5 μg/ml, while the mean concentration was < 0.1‐1.58 μg/ml in three patients who had uveitis attacks. We speculate that the uveitis attacks occurred in the three patients because of the low IFX concentrations, and shortened the IFX administration interval from 8 weeks to 6 or 7 weeks. Thereafter, two of the three patients did not have any uveitis attacks. The serum concentration of IFX in the two patients was increased from 0.1 to 5.5 μg/ml and 0.2 to 3.6 μg/ml, respectively, whereas the concentration in one patient who had uveitis attacks was <0.1 μg/ml, and the neutralizing antibody titre to IFX was negative. The serum concentration of IFX was correlated with its efficacy.

Conclusion Measurement of IFX serum concentration is useful to predict treatment efficacy in BD patients.
Suppression of TRPV 1 channels activity is a possible way in treatment of ophthalmic diseases
Authors: MIRONOVA E , GRISHIN E , PCHELINTSEVA O , KOROLKOVA U
Published: November 2013

Purpose The superfamily TRP (Transient Receptor Potential Channels), including subfamily TRPV (1‐6) channels, play an important role in regulation of eye homeostasis and development of ophthalmic pathology (Zhang F. et.all, 2007). The purpose of the paper is to study the possibility of suppression of TRPV1 channels activity that can promote braking of pathological processes in the cornea and the retina.

Methods In experiment the action of laminaria dry extract is investigated on the stable line of CHO cells, expressing the receptor of the rat TRPV1 (rTRPV1). This line was received with use of the T‐REx System (Invitrogene). kDNA coding rTRPV1, was cloned in an induced expressed vector of pcDNA4/TO. The expression of TRPV1 was induced by addition of tetracycline on cellular environment (1g/ml) in 24 hours prior to testing. The selected monoclones with the greatest level of an expression of TRPV1 were used. The fluorescent analysis was carried out with the automatic system of dispensing of NOVOstar liquids (BMG LABTECH). Change of cellular fluorescence (λex=485 nm, λem=520 nm) before and after stimulation of cells agonist TRPV1 ‐ capsaicin (400 nM) in the presence of various concentrations of laminariadry extract was studied. Measurements were performed at pH7.4 and 37 °C.

Results In experiment it was established that an application of the laminaria in concentration of 4‐5 mg/ml on cells with an expressed receptor of TRPV1 considerable falling (30‐50%) Ca2+ response of cells at a single activation of cells with the capsaicin.

Conclusion Thus, the extract of laminaria shows a considerable inhibiting activity in relation to TRPV1 to channels. It may be one of the ways in the treatment of ophthalmic pathology.
Reproducibility of retrobulbar blood flow velocity measurements using two different colour Doppler imaging devices
Authors: VERTICCHIO VERCELLIN AC , CUTOLO CA , DELLAFIORE C , LAVA M , RAIMONDI M , LANTERI S , ROLANDO M , LOMBARDO S , DISTANTE P , BOSSOLESI L , TINELLI C , MILANO G
Published: November 2013

Purpose To evaluate the intra and inter‐operator reproducibility of color Doppler imaging (CDI) in assessing blood flow velocity in the ophthalmic (OA), central retinal (CRA) and short posterior ciliary arteries (SPCA)

Methods The right eye of two group of 8 healthy volunteers was examined. Two radiologists and two ophthalmologists, divided into pairs, measured Peak Systolic Velocity (PSV), End‐Diastolic Velocity (EDV) and Resistivity Index (RI) of each vessel using a different CDI device for each group. The concordance between two measurements was evaluated with Lin's concordance correlation coefficient (CCC)

Results Globally very good degrees of intra‐operator concordance were obtained for the PSV (0,859), EDV (0,834) and RI (0,859) of the OA. There was moderate concordance for PSV (0,574) and EDV (0,594) and good concordance for RI (0,694) for the CRA. Good degrees of concordance were obtained for the SPCA measurements. However inter‐operator concordance was found globally poor

Conclusion These data show that retrobulbar vessels CDI measurements are operator dependent. To increase the intra‐operator and inter‐operator concordance rules should be adopted for timing of the exam and probe position to minimize the pressure applied on the eye
Fundus autofluorescence, OCT thickness evaluation, angiography and immunohistochemistry correlation in albino P23H rats
Authors: PINILLA I , FERNANDEZ‐SANCHEZ L , SEGURA FJ , SANCHEZ‐CANO A , FUENTES‐BROTO L , TAMARIT JM , LOPEZ DE LA FUENTE C , PEREZ‐GARCIA D , RAMIRO P , CUENCA N
Published: November 2013

Purpose To evaluate the correlation between OCT changes and fundus autofluorescence (FAF) with immunohistochemistry (ICC) findings in an animal model of RP, the P23H rat and to investigate retinal and choroidal vascularization using fluorescein and indocianin green angiography

Methods Twenty albino homozigous P23H line 1 rats aging from P18 to 27 months and wild‐type albino Sprague‐Dawley (SD rats) (2 and 11 months old) were used for this study. Normal pigmented Long Evans (LE) 2 months old were used to compare FAF findings. SLO imaging and OCT were acquired using an Spectralis system (Heidelberg Engineering, Germany). For checking FAF, fluorescence was excited using diode laser at 488 nm. Thickness measurements were evaluated avoiding the ones close to the optic nerve. ICC was performed to correlate with the findings of OCT and AF changes

Results During the course of P23H degeneration, the FAF pattern varied from not findings in young animals, some spotting at 2 months old to a mosaic of hyperfluorescent dots in the rats of 6 months or older. Retinal thicknesses diminished during the time. P23H rats showed great changes in morphology in advanced ages. Mean retinal thickness values varied from 189.88 μm at P60 to 58.15 μm at 27 months old. Retinal vascular plexus were diminished with time, and vessels exhibiting an abnormal, tortuous morphology could be observed.

Conclusion FAF is a non‐invasive procedure that can detect changes in metabolic activity at the RPE in animal models of retinal degeneration in vivo. OCT and ICC show a good correlation. Retinal vascular plexus changes with aging.
Proteomic analysis of the retina in mice deficient in glial fibrillary acid protein and vimentin
Authors: MANDAL N , HONORÉ B , VORUM H , PEREZ MT
Published: November 2013

Purpose Investigate the mechanisms underlying functional differences observed in glial fibrillary acid protein (GFAP) and vimentin knockout mice.

Methods Retinal tissue was harvested from 21‐day‐old mice lacking GFAP and vimentin (GFAP(‐/‐)vim(‐/‐); n=6), and age‐matched wild‐type (wt; n=6) controls. The retinal samples were evaluated by two‐dimensional polyacrylamide gel electrophoresis, SYPRO Ruby fluorescent stain, and PDQuest software image analysis. Protein spots that were differentially expressed between the two groups were processed for identification by tandem mass spectrometry, prior to further ongoing investigations with western blotting and immunocytochemistry.

Results Thirteen protein spots were found to be differentially expressed between the GFAP(‐/‐)vim(‐/‐) and wt mouse retinas, as determined by Mann Whitney U test with a significance level at p< 0.05.

Conclusion The proteins identified are involved in a wide range of biological processes that include glial cell differentiation and development, neuroprotective and neurotrophic actions, redox homeostasis, cell adhesion and migration, and cytoskeletal remodeling. This study will further our understanding of the role of GFAP and vimentin in the retina, and likely provide new insights into various conditions that involve retinal cell degeneration and glial cell activation.
Long‐term results and prognostic factors for visual acuity after diabetic vitrectomy: A 10‐year follow‐up study
Authors: OSTRI C
Published: November 2013

Purpose To report long‐term results and estimate long‐term prognostic factors for visual acuity following modern diabetic vitrectomy.

Methods Retrospective review of patient files from a large diabetes center between 1996 and 2010. Surgical history was obtained from the Danish National Patient Register. Follow‐up intervals were 3 months and 1, 3, 5 and 10 years after surgery.

Results In total, 167 patients had diabetic vitrectomy. Surgery indications were non‐clearing vitreous hemorrhage (47%) or tractional retinal detachment (53%). Median visual acuity increased from 0.06 before surgery to 0.21 after surgery (p<0.001) and stabilized. The proportion of patients with reading ability stabilized as from the 3‐month follow‐up. After 10 years, 66% of the operated eyes were pseudophakic or aphakic and 13% carried silicone oil. Preoperative iris rubeosis was correlated with inability to read after 1 and 3 years (p<0.04). Use of silicone oil was correlated with inability to read at all follow‐up examinations (p<0.05).

Conclusion After diabetic vitrectomy, visual acuity improved and stabilized as from the 3‐month follow‐up. The most consistent long‐term predictor of unfavorable visual acuity was use of silicone oil as tamponade agent. The results can be used to counsel patients on the risk of complications after surgery.
Live retinal image mosaicking during fundus examination with a computer‐assisted slit‐lamp prototype
Authors: GUILLEMOT C , RICHA R , COMUNELLO E , VON WANGENHEIM A , SCHNITZLER JY , WASSMER B , HAGER G , TAYLOR R , THURET G , GAIN P
Published: November 2013

Purpose Laser photocoagulation is the standard treatment for sight‐threatening diseases worldwide, namely diabetic retinopathy. The slit lamp biomicroscope coupled to the laser permit the visualisation of only a small portion of the retina, complicating the task of localizing and identifying laser targets, increasing treatment duration and patient discomfort. Aim: to assist ophthalmologist, we propose a method for creating intra‐operative retina maps for view expansion using a slit‐lamp biomicroscope

Methods Based on the mosaicking method previously described by Richa R (Medical Image Computing and Computer‐Assisted Intervention (MICCAI’12) the method was a combination of direct and feature‐based methods, suitable for the textured nature of the human retina. We used two major enhancements to the original formulation: (1) an efﬁcient pixel selection scheme for increased computational efﬁciency; (2) an entropy‐based mosaic update method for coping with the variable visualization conditions during the procedure. We also implemented a blending method to generate a photo‐realistic retina mosaic

Results Several experiments on retinal mosaicking in live on human (without laser at this moment) with a computer‐assisted slit‐lamp prototype will be presented

Conclusion Computer‐assisted slit‐lamp prototype could be usefull in a next future for retinal documentation and laser navigation

Commercial interest
Phacoemulcification with intravitreal bevacizumab injection in patients with cataract and diabetic clinically significant macular edema
Authors: CHEBIL A , CHAKER N , KORT F , JEDIDI L , LARGUECHE L , EL MATRI L
Published: November 2013

Purpose To evaluate efficacy of intravitreal injection of bevacizumab at the time of cataract surgery in patients with diabetic clinically significant macular edema.

Methods Eighteen diabetic patients, with clinically significant macular edema and cataract who have undergone phacoemulsification with intravitreal injection of 1.25 mg bevacizumab at the time surgery, were retrospectively evaluated. All patients were evaluated by spectral OCT before, 1 month, and 3 months after the surgery. The main parameters were the best‐corrected visual acuity (BCVA) and central macular thickness (CMT). Paired samples t‐test was used for statistical analysis.

Results The mean best‐corrected visual acuity was 0.16 ± 0.07 at baseline, 0.63 ± 0.44 at 1 month and 0.68 ± 0.12 at 3 months after the surgery. The BCVA levels recorded at 1 month and 3 months after the surgery were significantly higher than the initial BCVA (P = 0.001). The mean CMT was 384.4 ± 102.4 μm at baseline, 288 ± 44.1 μm at 1 month and 254.9 ± 11.9 μm at 3 months after the surgery. The CMT values recorded at 1 month and 3 months after the surgery were significantly lower than the initial CMT (P < 0.001, P < 0.001).

Conclusion Phacoemulsification with intravitreal injection of bevacizumab at the time of cataract surgery provides a decrease in CMT with a gain in BCVA in diabetic patients with clinically significant macular edema and cataract.
Branch retinal vein occlusion and vitreovascular traction: An SD‐OCT case‐control study
Authors: ASCASO FJ , PADGET E , VILLéN L , HUERVA V , ZABADANI K , DEL BUEY MA , CRISTóBAL JA
Published: November 2013

Purpose To determine the prevalence of vitreovascular traction at the obstruction site in patients diagnosed with branch retinal vein occlusion (BRVO).

Methods In this prospective observational case‐control study thirty‐two consecutive cases of BRVO were studied with spectral‐domain optical coherence tomography (SD‐OCT) to detect the presence of vitreovascular traction or vitreous adhesión at the occlusion site. The fellow eye was used as control.

Results SD‐OCT directed to the occlusion site revealed a vitreovascular traction in eight eyes (25%). In fourteen eyes (43.75%) an adherent posterior hyaloid without signs of traction was found. Regarding to the same vessel segment of the fellow eye, none of the controls revealed vitreovascular traction, while vitreous adherence was present in 12 (37.5%). Vitreovascular traction at the occlusion site was significantly associated with BRVO (p=0.024, Chi‐squared test).

Conclusion Vitreous traction at the occlusion site could play a role in the etiology of some cases of BRVO.
Spectral‐domain optical coherence tomography (SD‐OCT) patterns in macular edema associated with retinal vein occlusion
Authors: CHEOUR M , BROUR J , HACHICHA F , LAJMI H , MEHANAOUI D , SAFRA I , MAZLOUT H , KRAIEM A
Published: November 2013

Purpose To correlate spectral‐domain optical coherence tomography (SD‐OCT) characteristics of macular edema (ME) due to retinal vein occlusion (RVO) with mean best corrected visual acuity (BCVA).

Methods Fifty patients (50 eyes) having macular edema due to CRVO or BRVO, were retrospectively reviewed Statistical analysis was used to evaluate the relative contribution of several variables, including SD‐OCT characteristics such as baseline central retinal thickness (CRT), central intraretinal cyst size, serous retinal detachment (SRD) size, photoreceptor inner segment/outer segment (IS/OS) integrity and external limiting membrane (ELM) status with mean BCVA.

Results Thirty three patients had BRVO (66%), 14 patients (28%) had CRVO and 3 patients (6%) had HVO. Mean CRT was 574,52 µm. There was a strong correlation between CRT and visual acuity (CCP=0,41 ; P=0,003). Cystoid macular edema was present in 46 eyes (92%) with central intraretinal cyst in 36 eyes (72%). Mean BCVA was statistically better in eyes without central intraretinal cyst (P=0,015) but there was not a significant difference depending of the cyst size (CCP=0,28 ; P=0,09). SRD occurred in 22 eyes (44%) and mean thickness of SRD was 237µm. Mean BCVA was statistically better in eyes without SRD (P<0,001) but there was not a significant difference depending of the cyst size (CCP=0,27 ; P=0,21). IS/OS line was disrupted in 17 eyes (34%) and absent in 21 eyes (42%). Eyes without IS/OS line showed worse BCVA (P<0,001).Mean BCAV was better when IS/OS line was intact (P<0,001). MLE was intact in 6 eyes (24%) over 25 patients. Mean BCAV was statistically better when MLE was not disrupted (P<0,001).

Conclusion SD‐OCT is an important tool in macular edema evaluation. Our results suggest that baseline SD‐OCT characteristics, the status of photoreceptor IS/OS and ELM can be helpful in predicting the final visual outcome in patients with macular edema due to retinal vein occlusion.
AMD Drusenoid deposits characterization: Interest of OCT, OCT en FACE
Authors: GONZALEZ C
Published: November 2013

Purpose To study AMD drusenoid deposits with OCT en Face and see all the input of this technique and software

Methods 204 eyes of 102 patients, 32 men, 70 women, with AMD drusenoid deposits (Cuticular drusen, Subretinal drusenoid deposits, soft Drusen, Drusenoid PED,Pseudovitelliform AMD). Deposits were evaluated by OCT, notably OCT en FACE (Spectralis HRA‐OCT, spectral domainOCT). Autofluorescence, IR imaging, ETDRS visual acuity (VA), complete ophthalmic examination with Fundus exam were added. The size, characteristics, number, topography of the lesions, their growth way were evaluated, as well as their environment above and below (particularly IS‐OS, plexiform layer, choriocapillaris structure and thickness). Each element was studied, compared cut to cut, layer to layer and time to time to itself and to each other data, every 4 months.

Results VA improved in 85% cases, stabilized in 15%. AF imaging and their region finder analyze were the main elements of the atrophic lesions’ study. The surface of the atrophic area grows by 17%, the edge changes in 20%. Speed growth was in average 1,15mm2/year. At OCT, thickness of photoreceptor, pigment epithelium layer diminished about 25% and 35% at the area’s edge. Choriocapillary depth values, FA and ICG data were mainly significative in the large atrophic areas and less than AF indications. This protocol has a little impact on the evolution of atrophic areas, apparently less than monthly IVT, and the same as AMD by itself.

Conclusion The study of atrophic process and its progression is a main question in the AMD follow –up, the evaluation of the protocol treatments and their safety too.
Multispectral retinal image analysis (MRIA) for the assessment of subretinal fibrosis in neovascular age‐related macular degeneration (nAMD)
Authors: CALCAGNI A , STYLES IB , PALMER AD , SHEN Y , BARTLETT H , EPERJESI F , GIBSON JM , CLARIDGE E
Published: November 2013

Purpose To investigate the use of MRIA for quantitative characterisation of subretinal fibrosis secondary to nAMD.

Methods MRIA images of the posterior pole were acquired over 4 months from 20 eyes including those with inactive subretinal fibrosis and those being treated with ranibizumab for nAMD. Changes in morphology of the macula affected by nAMD were modelled and reflectance spectra at the MRIA acquisition wavelengths (507, 525, 552, 585, 596, 611 and 650nm) were computed using Monte Carlo simulation. Quantitative indicators of fibrosis were derived by matching image spectra to the model spectra of known morphological properties.

Results The model spectra were comparable to the image spectra, both normal and pathological. The key morphological changes that the model associated with nAMD were gliosis of the IS‐OS junction, decrease in retinal blood and decrease in RPE melanin. However, these changes were not specific to fibrosis and none of the quantitative indicators showed a unique association with the degree of fibrosis. Moderate correlations were found with the clinical assessment, but not with the treatment program.

Conclusion MRIA can distinguish subretinal fibrosis from healthy tissue. The methods used show high sensitivity but low specificity, being unable to distinguish scarring from other abnormalities like atrophy. Quantification of scarring was not achieved with the wavelengths used due to the complex structural changes to retinal tissues in the process of nAMD. Further studies, incorporating other wavelengths, will establish whether MRIA has a role in the assessment of subretinal fibrosis in the context of retinal and choroidal pathology.
Intercellular trafficking of Alu RNAs causes geographic atrophy expansion in AMD
Authors: BASTOS CARVALHO A , KERUR N , KIM Y , FOWLER B , GELFAND B , AMBATI J
Published: November 2013

Purpose Age‐related macular degeneration (AMD) accounts for the bulk of blindness in the elderly in Western societies. The hallmark of advanced atrophic AMD, geographic atrophy (GA), is loss of retinal pigment epithelium (RPE) cells that expands centrifugally over time. We previously identified decreased abundance of the enzyme DICER1 and accumulation of its substrate Alu RNA in RPE cells as a cause of GA (Kaneko et al. Nature, 2011). We hypothesized that disease progression is due to transfer of cytotoxic Alu RNA from dying RPE to neighboring healthy cells by means of bleb/microvesicle RNA trafficking.

Methods Human RPE or 661W cells were transfected with DICER AS oligonuclotide. Blebs/exosomes were collected from conditioned media by differential centrifugation. RNA content of the isolated fractions was quantified by qPCR. For live cell imaging, FITC‐Alu RNA transfected hRPE were stained with Fluorescent Cellvue®. Subretinally injected mouse eyes were stained (anti‐ZO1), flatmounted and imaged with confocal microscopy.

Results Blebs and microvesicles isolated from DICER1‐deficient RPE cells show increased abundance of Alu RNA. Additionally, exposing healthy RPE or photoreceptors to conditioned medium from Alu‐enriched cells leads to cell death. Live cell imaging identified the presence of FITC‐Alu RNA in Alu‐naïve cells co‐cultured with cells transfected with the fluorescently tagged RNA. Further, we demonstrate that subretinally injected vesicles induce RPE degeneration in mice.

Conclusion These data provide evidence for “neighborhood poisoning” as a mechanistic basis for progression of atrophic AMD. Targeting intercellular spread of Alu RNA holds therapeutic promise for inhibiting expansion of this devastating disease.
Central serous chorioretinopathy in pregnacy: A report of two cases
Authors: CARAMELLO ÁLVAREZ CM , HERRERA L , CRUZ N , ZABADANI K , PINILLA I , ASCASO J , CRISTóBAL JA
Published: November 2013

Purpose Pregnancy has been implicated in the pathogenesis of central serous corioretinopathy, along with stress, steroids, Cushing’s syndrome, systemic hypertension and lupus erythematosus.We present two cases of central serous corioretinopahty (CSC) during otherwise healthy pregnancies.

Methods Two patients that developed CSC during pregnancy are studied. Ophthalmological findings including visual acuity, slit‐lamp biomicroscopy, fundus examination, fundus photography and optical coherence tomography are presented. Patients were re‐evaluated six months after delivery.

Results Both patients had spontaneous resolution of CSC after delivery.

Conclusion CSC is a benign, self‐limited disease that can present with or without white retinal exudates. Elevated levels of glucocorticoids, present during pregnancy, can contribute to the pathogenesis of this entity.