bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insights into the molecular basis of rhegmatogenous retinal detachment
Authors: BISHOP PN 
Published: September 2009

Abstract Purpose Factors that determine the likelihood of developing posterior vitreous detachment and subsequent rhegmatogenous retinal detachment (RRD) include (i) the degree of vitreous liquefaction (ii) the strength of post‐basal vitreoretinal adhesion and (iii) the topology of the posterior border of the vitreous base. The purpose of these studies was to investigate each of these using a combination of ultrastructural and molecular techniques. Methods Ultrastructural studies of the human vitreous and vitreoretinal interface were performed in combination with various antibodies and cationic dyes. Biochemical studies were performed on extracted vitreous components. Results The resultant data suggest that: (i) vitreous liquefaction is caused by the aggregation of vitreous collagen fibrils and this is due to a loss of type IX collagen proteoglycan from the fibril surfaces; (ii) interactions between heparan sulphate proteoglycans in the inner limiting lamina and components on the surface of cortical vitreous collagen fibrils contribute to postbasal vitreoretinal adhesion; (iii) the posterior border of the vitreous base migrates posteriorly with aging due to the synthesis of new vitreous collagen by the peripheral retina. Conclusion The molecular basis of RRD is starting to be unravelled. Furthering our understanding of the underlying molecular processes may lead to the development of novel therapeutic strategies to treat RRD and other vitreoretinal disorders.
Ocular Response Analyzer waveforms analysis in normal and post‐laser in situ keratomileusis eyes
Authors: FRANCO S , FONSECA V , LIRA M 
Published: September 2009

Abstract Purpose Many clinicians have noticed that the morphological signal produced by Ocular Response Analyzer (ORA) (Reichert) is a unique “signature” for the eye being measured and suggested that probably there is other valuable information contained in these signals. This study explores the possibility of using information contained in these waveforms comparing them between normal and post‐LASIK eyes. Methods Corneal biomechanical properties of 40 normal eyes and 20 post‐LASIK eyes were obtained with ORA. Corneal thickness was measured with the SP‐100 Handy pachymeter (Tomey). Data aquired by ORA was exported to an Excel worksheet to obtained parameters such as areas of both the applanation and pressure signal curve, area of the “in” and “out” applanation curves, maximum applanation peaks, maximum of the pressure signal. Results There were significant differences between normal eyes and those submitted to LASIK for almost the studied parameters. Normal eyes show a bigger applanation curve area(p<0.001); the first peak maximum as well as its area are higher than for post‐LASIK corneas (p<0.001). For the second peak there are no statistically significant differences between normal and post‐LASIK eyes. Areas of both applanation peaks shows no significant differences for the post‐LASIK eyes (p=0.794) contrary to that observed in normal eyes. Post‐LASIK eyes show a lower maximum for the pressure signal curve and a smaller area for the second half of the pressure curve than for the normal eyes. Conclusion The results obtained indicate that there is more information in ORA measurements than have been used. Some of the corneal biomechanical properties studied, as weel as waveforms, have not the same behavior in normal and in post‐LASIK eyes.
Novel mutations and electrophysiological findings in RGS9 and R9AP associated retinal dysfunction (Bradyopsia)
Authors: HOLDER GE , MICHAELIDES M , LI Z , RANA NA , RICHARDSON EC , HYKIN PG , MOORE AT , WEBSTER AR 
Published: September 2009

Abstract Purpose To describe the phenotypic characteristics of patients with mutation in RGS9 or R9AP, which give rise to the disorder "bradyopsia" Methods Patients were ascertained according to history, examination and electrophysiological recordings. ERGs were performed in excess of the ISCEV standard better to characterise retinal function, and included S‐cone ERGs, ON‐OFF ERGs, and dark adapted ERGs to a bright flash with extended inter‐stimulus intervals. Blood samples were taken for DNA extraction from affected subjects and where possible unaffected relatives. Mutation screening of RGS9 and R9AP was performed. Results Four subjects were found to harbour mutations in RGS9 or R9AP, with three being novel. Three subjects, two Pakistani sisters and an Afghani female, had mutations in R9AP. The remaining patient, a British male, had a compound heterozygous mutation in RGS9. All mutation positive subjects had characteristic electrophysiological findings with, in particular, severely abnormal photopic cone ERGs (with relative S‐cone sparing) but normal dark adapted cone ERGs, and the need to use a prolonged inter‐stimulus interval to allow recovery from a dark‐adapted bright flash. Clinically, the patients had a stationary cone dysfunction syndrome, including mild photophobia; normal colour vision; normal fundi; and no nystagmus. Conclusion Novel electrophysiological features are described in association with RGS9 and R9AP mutations. The distinctive electrophysiological features associated with RGS9 and R9AP mutations enable directed genetic screening, and allow the distinction from patients with Oligocone Trichromacy, who present with a similar clinical phenotype.
Ultrasound biomicroscopy for the analysis of the anterior segment
Authors: PEDROTTI E 
Published: September 2009

AbstractThe conventional ultrasound imaging allows to study easily the structures of the eye, even if the obtained informations have a maximal definition of 500‐600 um and a maximal depth of 30‐40 mm. This definition, sometimes, is not enough to study the microscopical structures, such as cornea, iris, anterior chamber angle, ciliary bodies and zonula. The ultrasound biomicroscopy (UBM) was born to achieve a greater definition of the acquired images. This method, originally developed by Pavlin, Sherar, and Foster, allow the exploration of smaller and superficial structures, in particular of the anterior segment, with a spatial definition in vivo similar to histological preparations. The ultrasound biomicroscopy, thanks to high frequency of 50‐100 MHz, can reach a depth of 5 mm with a definition of 50‐60 um, unthinkable with conventional ultrasound. The application fields of this technique are pathologies of conjunctiva, cornea, iris, zonula, ciliary body and lens. The best informations are given especially when we have to study the angle of anterior chamber and ciliary body in glaucoma, cancers of the anterior segment, the artificially outflow roads in glaucoma surgery and the accommodation mechanism. This technique have two main concerns, the repeatability of the measures is operator‐dependent, as each ultrasound technology, and then it is a contact method. Even if new no contact and operator independent technologies are emerging, like interferometry and Scheimpflug Camera, UBM is actually undoubtedly the gold standard for the study of the anterior segment structures.
Diffuse keratoconjunctival diseases: an in vivo confocal microscopic study
Authors: DUA HS , MIRI A , ALOMAR T 
Published: September 2009

Abstract Purpose To establish in vivo confocal microscopic features of diffuse ocular surface disease. Methods IVCM of diffuse OSD such as chemical burns, inflammatory disease related limbal stem cell deficiency, conjunctival intraepithelial neoplasia and OS infections was carried out using the Rostock Cornea Module RCM and HRTII. In some patients subsequent biopsy or surgery allowed for histological correlation of the observed IVCM features. Results Multiple clinical and histological correlations have enabled us to establish diagnostic features of dendritic cells, inflammatory cells, metaplastic and dysplastic superficial and basal epithelial cells, goblet cells, intraepithelial cysts, corneal new vessels, subtypes of acanthamoeba cysts and other nonspecific features. These features can be seen individually or in combination in different diseases entities. Conclusion IVCM can help in making rapid clinical diagnoses without resort to biopsy or impression cytology. This in turn allows for early initiation of appropriate treatment.
Commercial interest
Optical simulation of large and small angle scatterers
Authors: DE BROUWERE D , GINIS H , PALLIKARIS IG 
Published: September 2009

Abstract Purpose However corneal scattering is clinically often quantified as haze (backscattered light), the visual function is affected by the forward light scattering in the anterior ocular media. The angular light distribution of the scattered light is inherent to the interaction between the light and the scattering media. The purpose of this study is to describe an optical model of the scattering tissues in the cornea and compare its light propagation to experimental single pass scattering measurements. Methods Histologic data and confocal imaging of the cornea revealed that a significant portion of corneal scattering originates by keratocytes and scar tissue created during a wound healing process, e.g. after refractive surgery. Keratocytes were modeled as small spheres, angular scattering distribution is derived on the Mie theory. The parameters were optimized to meet the light distribution measure by a single pass experiment through excised rabbit corneas. Results Single pass scatter measurements of excised rabbit corneas revealed a narrowly forward peaked scattering distribution (FWHM 30 arcmin), corresponding to a distribution of scattering spheres with 36μm+/‐15 radius and a relative refractive index of 1.0024. Scattering ratio (SR), equal to the scattering cross section, varied from 0.2 (clear) to 0.7 (scarred). The SR was correlated with the scar tissue thickness (0.79) and haze grade (0.51), Pearson's coefficient. Conclusion Despite the non‐spherical geometry of keratocytes, we presented a simple model to describe the corneal scattering distribution, controlled by physically relevant parameters as observed in histologic and confocal microscopy. Optical simulations based on light propagation through random phase maps may result in more realistic scattering models.
Intraocular straylight screening in medical testing centres for driver licence holders in Spain
Authors: MICHAEL R , VAN DEN BERG TJTP , BARRAQUER RI 
Published: September 2009

Abstract Purpose To test the performance of the C‐quant straylight meter during the daily routine work in medical testing centers for driver license applicants and driver license holders in Spain. Methods Altogether 914 subjects, of which 376 younger than 35 years, 428 between 35 and 60 years and 110 over 60 years were measured with the C‐quant in three medical testing centres (Barcelona, Zaragoza and Palma de Mallorca) in 2006. Technicians were instructed once and the measurements were done during the daily routine work. We recorded: age, BCVA, self‐reported subjective blinding at night; and from the C‐quant: straylight parameter (log s), measurement quality parameters (ESD, Q) and test duration. Results Total C‐quant test duration increases slightly with age from a mean of 7 min (<35 years) to a mean of 9 min (>60). At first attempt, 82% of all subjects produced reliable results (ESD < 0.12). The straylight parameter for this group was independent of ESD and ESD was independent of total test duration. The known age dependence of the straylight parameter and the weak correlation with BCVA was confirmed. The distribution of subjective blinding at night was very different between test centres. Subjects with "very strong" subjective blinding had significantly higher straylight values than subjects with "no" subjective blinding. Subjects avoiding night driving had significant higher straylight values than subjects driving at night. Conclusion The C‐quant measure is reasonable fast. Good subject instruction is important to get first attempt reliable results. Self‐reported subjective blinding results depend strongly on the interviewer. The C‐quant is an improvement over present methods, because it is objective and cannot be influenced.
Immune regulatory effect of rapamycin and cyclosporine A on experimental corneal allograft survival
Authors: STANOJLOVIC S , SCHLICKEISER S , APPELT C , VOGT K , SCHMITT‐KNOSALLA I , HAASE S , RITTER T , SAWITZKI B , PLEYER U 
Published: September 2009

Abstract Purpose To analyze the efficiency of low dose systemic treatment with rapamycin (Rapa) alone or in combination with cyclosporin A (CsA) in preventing corneal allograft rejection in a high responder strain combination. Methods A total of 80 C57BL/6 mice received corneal grafts of BALB/c donors. Recipients were treated with CsA 3mg/kg/day or Rapa 0.5mg/kg/day monotherapy or received combined treatment. Intraperitoneal injections were started on the day of surgery and continued for 14 days. In addition, corneal samples were subjected to real time RT‐PCR analysis for cytokine transcription. The frequency of CD4+CD25+Foxp3+ T regulatory cells (Treg) in secondary lymphoid organs were measured by flow cytometry. Memory T cells were estimated by Elispot. Results Monotherapy with Rapa significantly delayed allograft rejection (p=0.03). However, the combination of low dose Rapa and CsA prolonged corneal allografts survival at a significantly higher level (MST=17.1 ± 1.37 days, p=0.000004). Addition of CsA to Rapa resulted in down‐regulation of intragraft CD3, IL‐2, IFN‐γ and IL‐10 transcription (p=0.028, p= 0.027, p=0.028 and p= 0.027 respectively). Rapa alone increased the frequency of CD4+CD25+Foxp3+ Tregs in draining lymph nodes, whereas addition of CsA reduced Tregs. Rapa monotherapy as well as combined treatment prevented development of alloantigen specific IFN‐γ producing memory T cells in spleen. Conclusion Combined treatment with low dose CsA and Rapa resulted in superior graft survival and effectively modulated mRNA expression of inflammation and infiltration markers. Supported by DFG (150/14‐2) and SFB650 TP14
Effect os mitomycin C on the cicatricial corneal response on laser‐assisted subepithelial keratectomy to correct myopia
Authors: CANADAS SUAREZ P , GARCIA‐GONZALEZ M , ARRANZ‐MARQUEZ E , TEUS M 
Published: September 2009

Abstract Purpose To evaluate the influence of mitomycin C (MMC) on the predictability of refractive results after myopic laser‐assisted subepithelial keratectomy (LASEK). Methods This retrospective study comprised 1020 consecutive eyes that had LASEK to correct myopia. MMC 0.02% was applied for 30 seconds over the ablated cornea in all cases. Due to the use of MMC, the programmed ablation was 10% less than the intended correction to avoid overcorrection. The relationship between preoperative spherical equivalent (SE) and the 3‐month postoperative SE was analyzed by lineal regression. We also compared the refractive result in the quartiles with the lowest and the highest preoperative myopia. Results Preoperatively, the mean SE was ‐5.29 ± 2.6 diopters (D). 3 months post‐op, the mean residual SE was +0.16 ± 0.4 D in the lowest quartile (≤ ‐3.25D) and ‐0.32 ± 0.8 D in the highest quartile (≥ ‐7D) (p=0.0001). The mean cylinder was ‐0.27 ± 0.4 D in the lowest quartile and ‐0.41 ± 0.5 D in the highest quartile (p= 0.003). There was a significant (p=0.0001, r2= 0.15) correlation between the preoperative and postoperative SE (i.e., the higher the preoperative SE, the greater the undercorrection). Conclusion MMC seems to influence the spherical refractive outcomes after myopic LASEK. Using a 10% fixed hypocorrection, LASEK with MMC tends to overcorrect low myopic defects and undercorrect high myopias.
3 Intravitreal ranibizumab injections series for the treatment of neovascular age‐related macular degeneration (AMD), 18 months follow‐up
Authors: GONZALEZ C 
Published: September 2009

Abstract Purpose To evaluate the functional, anatomical, vascular flow effects of intravitreal Ranibizumab injections(IVT) for retrofoveolar neovascular AMD, done with a series of 3 IVT protocol, and the recurrences frequency at 1 ½ year evolution. Methods 227 eyes of 179 patients, 58 men, 121 women, with retrofoveolar neovascularisation complicating AMD. Patients received intravitreous Ranibizumab, 3 times, every 4 weeks in an inductive treatment. The next injections depended on the follow‐up results, and were done by series of 3. First and 2 months’ interval follow‐up exam included ETDRS visual acuity (VA), complete ophthalmic examination, fluorescein and infracyanine (ICG) angiography, and optical coherence tomography (OCT).VA and OCT were done before each IVT. We want to evaluate the incidence of this protocol on the frequency of recurrences so on the number of IVT needed. Results VA improved in 48% cases, more than 10 letters in 25% cases. Angiographic leakage reduced about 70% in 53% cases. At ICG ,vascular flow, vessel’s diameter were 2/3 time less in 62% cases. Diffuse edema was 30% reduced in 85% , pigment epithelial detachment was flattened and less dense in all cases, by OCT. Most of patients had good functional, anatomical, vascular flow, results, with less IVT needed. Inductive treatment was sufficient in 113 cases,more series were necessary in 114 cases.Mean stability period was 3 months. Conclusion The results, with generally improved visual function, less and/or stable neovascular activity in FA‐ICG‐OCT, less recurrences, suggest series of 3 Ranibizumab IVT seem effective, less restrictive,more retinal protective, lastly cheaper. This protocol seems attractive, its indication must be optimized.
Outcome of exudative aged‐related macular degeneration (ARMD) after 3 intravitreal injections of bevacizumab
Authors: CREUZOT C , BIDOT ML , SOUCHIER M , MALVITTE L , BRON AM 
Published: September 2009

Abstract Purpose To evaluate the efficacy of intravitreal injections of bevacizumab in exudative ARMD. Methods Retrospective study including naive patients suffering from exudative ARMD whatever the type of neovascularisation. All the participants were treated with three monthly 1.25 mg intravitreal injections of bevacizumab.The primary objective was far and near visual acuity (VA) 1, 3 and 6 months after the third injection. The secondary objective was the residual activity of neovascularisation assessed with fluorescein and ICG angiography and retinal thickness evaluated with OCT3. Results 71 eyes of 66 patients were included. Neovascularisation was occult, visible or combined in 65%, 20% and 15% of the cases, respectively. A statistically significant improvement between pre and post‐injection VA (LogMAR) was observed one month after the third injection, 0.88±0.57 and 0.77±0.60, respectively, p=0.001). An active neovascularisation was still present at that time in 57.7% of the eyes and 34% at 6 months needing further bevacizumab injections (3.85±0.96 per eye). VA was similar at 1, 3 and 6 months (F71,2=1,54 ; p=0,46). A complication occurred in 3 eyes. Conclusion Three bevacizumab intravitreal injections led to a significant VA improvement. However, more than half of the eyes had an active neovascularisation after these 3 injections.
Focal photodynamic therapy for idiopathic polypoidal choroidal vasculopathy
Authors: POPOSKI V , VILAPLANA D , ALARCON I , MARTINEZ‐GIRALT O , POPOSKA D , CASTILLA M 
Published: September 2009

Abstract Purpose To evaluate the focal treatment with photodynamic therapy (PDT) to treat idiopathic polypoidal choroidal vasculopathy (IPCV). Methods Retrospective study of 8 eyes of 6 patients with visual loss and diagnosed of IPCV. Diagnosis was confirmed with indocyanine green (ICG) angiography. We treated with PDT only the “hot spots” or the maximum hyperfluorescence focal area. In the first month, funduscopic and visual acuity examination using ETDRS optotype were performed. In the third month all the examinations including a fluorescein and ICG angiography were repeated. Afterwards, controls had taken place every 6 months. Results Five women and one men were included in the study. Its age was between 64 and 85 years. Mean follow‐up was 18.1 months (range: 6‐35 months). Mean initial and final visual acuity were 20/100 and 20/80 respectively. We observed a visual acuity improvement in 6 eyes and a visual stability in 2 eyes. Five eyes needed only one treatment, 2 eyes two PDT sessions and only one eye required 5 PDT sessions. Conclusion In our study, focal photodynamic therapy of “hot spots” has shown to be an effective, non invasive and secure treatment for idiopathic polypoidal choroidal vasculopathy.
Combined 23‐gauge sutureless pars plana vitrectomy (ppV), injection of recombined tissue plasminogen activator (rtPA), expansile gas and bevacizumab treating acute subretinal haemorrhage (SRH) in exudative AMD
Authors: MAIER M , PERZ C , FEUCHT N , KONRAD J , WINKLER VON MOHRENFELS C , LOHMANN CP 
Published: September 2009

Abstract Purpose To evaluate the effect of 23‐gauge core ppV with consecutive intravitreal injection of rtPA, gas and bevacizumab for the displacement of SRH in patients with exudative age‐related macular degeneration (AMD). Methods The retrospective, non‐randomized case study included 15 eyes of 15 patients aged 74 to 89 with SRH resulting from exsudative AMD. Each patient was treated with 23‐gauge ppV and injection of 0.05 ml rtPA (50 μg), 0.3 ml of sulphur hexafluoride (SF6) gas and 0.05 ml bevacizumab (1.25 mg). Visual acuity (VA), lesion size measured by fluorescein angiography (FA) and retinal thickness as determined by optical coherence tomography (OCT) were evaluated pretreatment as well as 1, 3 and 6 months postoperatively. Results The mean visual acuity pretreatment was 20/400. The figure remained constant until month 3 postoperatively. At 6 months, the mean VA had improved to 20/200. No patient had reading ability before treatment. 1 month postoperatively reading VA was achieved in 6 %, rising to 27% at 6 months. There was a reduction in retinal thickness in 8 patients measured by OCT. FA showed a reduction of lesion size in 10 out of 15 patients. Conclusion The combined application of rtPA, gas and bevacizumab via 23‐gauge PPV for the treatment of SRH secondary to exudative AMD appears to be a safe and effective method. In our study, the combined treatment including the injection of bevacizumab enabled 27 % of patients to achieve reading ability at 6 months postoperatively.
Accommodation and pupillary response in the reading of texts with varying cognitive demand
Authors: MIHELCIC M 
Published: September 2009

Abstract Purpose The relationship of the pupil size changes and lag of accommodation during reading of texts with varying cognitive demand was examined to determine whether the content of reading has significant influence on the accommodative and pupillary response. The results are discussed in regard to possible impact on myopia growth. Methods The study included 112 high school students (84 female, 28 male) aged 17 to 19. At the distance of 40 cm (=2.5 D) five short texts with different cognitive demands were presented on a laptop screen. From 1.0 m distance, the measurements of pupil size and accommodation were taken using the Plusoptix Power Refractor. Results Accommodative lag was found to be very stable during all the tests, with the mean value of 0.275 D. On the other hand, the pupil size varied significantly, depending on the mental effort and type of cognitive involvement. Smallest pupils were associated with the reading of advanced philosophically blended texts (4.79 mm), whereas texts with simple calculations were associated with greatest pupil size (5.08 mm). The difference between the these two was statistically significant with p = 0.0024. Conclusion Young subjects reading contents with higher cognitive demand, particularly those that require instant reasoning, have larger pupils than subjects reading philosophical novel‐like texts. Larger pupils are associated with more exaggerated aberrations and smaller depth of focus. With consistent lag of accommodation and considering accommodative microfluctuations, retinal image in this case must be blurrier or at least closer to the blur point. It can be concluded that the content of reading itself is a factor in nearpoint stress and could hipotetically contribute to myopia growth.