bluuebunny/crossref_metadata_2025_split huggingface dataset:
Basic principles of radiotherapy in ophtalmic oncology
Authors: DENDALE R , FOURNIER ‐ BIDOZ N , CAMPITELLI M , CALUGARU V , LUMBROSO ‐ LE ROUIC L , LEVY C , PIERRAT N , MAZAL A , DESJARDINS L , FOURQUET A 
Published: September 2009

AbstractOphtalmologic Radiation Oncology concerns intra ocular tumors, orbital tumors and eyelid tumors. In these locations, tumors are often close to normal critical tissues, increasing the risk of radiation toxicities. Basic principles of ophthalmic radiotherapy are not really different from radiotherapy of others organs. They are based on a precise description of the tumor volume, knowledge of potential tumor local or regional extension, knowledge of tissue biological radiosensitivity for tumors and the surrounding normal tissues. Based on these features, treatment modalities (radiation treatment length and fractionation) are determined to fulfill the aims of medical curative intents: good local control with acceptable toxicities or the aims of medical palliative intents: to relief with minimal toxicities. Many types of radiation therapy can be used for ophthalmic tumors: brachytherapy, orthovoltage radiotherapy, conformal therapy with photons and electrons including intensity modulated radiation therapy, protontherapy, and the use of specific devices such as CyberKnife and Tomotherapy. All of these techniques have their advantages and their disadvantages, leading the radiation oncologist to make a choice depending on the tumor site and characteristics.
The treatment of uveal melanoma by ruthenium plaques
Authors: DAMATO B 
Published: September 2009

Abstract Purpose Plaque radiotherapy is the first choice of treatment for choroidal melanomas. The standard practice is to position the plaque centrically in relation to the tumour, with a 2mm physical safety margin in all directions. The author has developed techniques for administering brachytherapy with plaques positioned eccentrically, with their posterior edge aligned with the posterior tumour margin. This allows a higher apex dose to be given while reducing the radiation delivered to optic nerve and fovea. Methods The tumour is localized by transillumination and its anterior margin marked on the sclera with a pen. The 'plaque‐tumour difference' measurement is then marked on the sclera at the point where the anterior plaque margin should be. A transparent plaque template is sutured to the sclera. The position of the plaque is checked with a right‐angled fibre‐optic transilluminator, which is passed through a perforation near the posterior edge of the template. If the template is positioned correctly, then with binocular indirect ophthalmoscopy one should see the 'sunset sign', which occurs when the transilluminator is exactly at the posterior tumour margin. Results Eccentric ruthenium plaque positioning has been practised in Liverpool for over a decade. The results have been published. Local tumour control rates have been good (partly because of case selection). Radiation maculopathy and optic neuropathy have been rare if the tumour has not extended within 1 mm of these structures. The main cause of visual loss has been maculopathy, caused by exudation from the irradiated tumour. Methods for treating such exudation are described. Conclusion Plaque radiotherapy is effective for choroidal melanomas up to 5 mm in thickness. It achieves good local tumour control with preservation of vision in most cases.
Principle of adaptive optics
Authors: SÖDERBERG PG 
Published: September 2009

Abstract Purpose To provide an overview of adaptive optics imaging of the retina. Methods In ophthalmoscopical imaging, the two dimensional spatial radiance variation of the back scattered light from the retinal surface is measured. Perfect imaging would require that light backscattered from one point on the retina examined is refocused to one point on the detector. Due to diffraction, light scattering and aberrations, some of the light, injected into the eye examined and some of the light back scatted from the retina examined, are deviated. This leads to loss of contrast. Aberrations induced are, for each individual, specific to the optics of the eye examined. In AOSLO, in addition to confocal illumination and light detection, aberrations induced by the optics of the eye examined are individually measured by wave front sensing and corrected for. Results In the AOSLO, a wave front sensor is introduced between the light source and the eye examined. The information from the wave front sensor is fed back to a deformable mirror, also placed in between the light source and the eye examined. The deformable mirror corrects the wave front aberrations induced by the optics of the eye examined. This allows the injected light to form a point on the retinal surface and simultaneously, the backscattered light from the retina of the eye examined to be focused to a point on a detector. An x‐y scanner in front of the eye allows sequential illumination and capturing of aberration minimized back scattered light from an x‐y matrix of the retinal surface of the eye examined. The relative radiances measured in the x‐y matrix represent the image. Conclusion Adaptive optics in ophthalmoscopy improves contrast in the image of the retina examined by correcting for aberrations induced by the optics of the eye examined.
Telangiectasia evaluated with adaptive optics and HR‐OCT
Authors: ATMANI K , LEVEZIEL N , SOUBRANE G 
Published: September 2009

Abstract Purpose Type 2 Macular Telangiectasia is a progressive disease starting in the fifth to seventh decade and characterized by a progressive damage of the neurosensory retina.. The purpose of this study is to compare the images obtained using two non‐invasive techniques, High‐Resolution Optical Coherence Tomography (HR‐OCT) and Adaptive Optics (AO), in Type 2 Macular Telangiectasia. Methods Nine eyes of 5 patients affected by Type 2 Macular Telangiectasia underwent examination including visual acuity measurement with ETDRS (Early Treatment of Diabetic Retinopathy Study) chart, color photographs, monochromatic photographs, Spectral‐Domain Optical Coherence Tomography with Heidelberg Spectralis™ OCT and Adaptive Optics assessment with Imagine Eyes™ System. The neurosensory retina and the photoreceptor layer were analyzed using both HR‐OCT and AO imaging. Results The disruptions of the photoreceptor layer on HR‐OCT correspond to a cellular loss on Adaptive Optics Imaging. On the other hand, Adaptive optics Imaging allows the measurement of cellular density in areas which have a normal aspect on HR‐OCT. Conclusion The diagnosis of Macular Telangiecctasia is based on biomicroscopy and fluorescein angiography. Adaptive Optics Imaging is helpful to analyze the retinal damages, especially the cone abnormalities. This technique will certainly allow a better understanding of this rare disease. Author Disclosure Information: K. Atmani, None; N. Leveziel, None G. Soubrane, None.
Drusen in adaptive optics and SD‐OCT
Authors: MASSAMBA N , LAMORY B , SOUBRANE G 
Published: September 2009

Abstract Purpose The study objective was to explore the microscopic structure of soft macular drusen and surrounding retinal areas using an adaptive optics (AO) camera and to compare the findings to those from standard clinical examinations. Methods 18 patients of age between 65 and 85 and presenting soft macular drusen were recruited after aninitial scanning laser ophthalmoscope (SLO) examination. We used an AO flood‐illumination system to acquire high‐resolution images of selected drusen areas. Every acquisition provided a series of 20 consecutive reflectance images, out of which 10 were numerically averaged to produce an enhanced final image. The resulting AO images were analyzed in comparison with conventional infrared and autofluorescence fundus images and spectral optical coherence tomography scans. Results The soft drusen were visible in AO images as generally round areas delimited by a peripheral low‐reflectance line. Hyper reflective spots of size comprised between 2 and 15 μm were observed in many drusen inner areas. These bright spots were sometimes isolated, sometimes grouped into tight aggregates of 2 to 40 components. Cone photoreceptors were visible in areas between drusen in most AO images. Conclusion The microscopic structures observed in the AO images of soft drusen presents analogies with their described anatomopathologic characteristics, which could not be identified using other in vivo imaging techniques. AO technology could help to refine the clinical classification of macular drusen and obtain deeper insight in their link with the development of different types of advanced AMD. Author Disclosure Information: N. Massamba, None; B. Lamory, Imagine Eyes, G. Soubrane, None.
Comparison of macular pigment optical density (MPOD) between a northern European and a Mediterranean population
Authors: TSIKA C , MAKRIDAKI M , PLAINIS S , TSILIMBARIS M , PALLIKARIS IG 
Published: September 2009

Abstract Purpose To investigate the Macular Pigment Optical Density (MPOD) differences between a northern European and a Mediterranean population. Methods MPOD was measured psychophysically using Heterochromatic Flicker Photometry in 71 healthy subjects from northern Europe (18 Dutch and 53 British). 74 healthy age‐matched Cretans (Greece) underwent the same measurements according to the same protocol. None of the subjects was taking any carotenoids supplements. The comparison of MPOD between the two populations was statistically assessed with a Generalized Linear Model of regression. The effect of age and gender was taken into consideration. Results The mean MPOD of the northern Europe population was 0.43 (CI 95% 0.39‐0.47) and the mean age 45 years old (±19). No effect of age (p=0.402) or gender (p=0.074) was revealed into this group. Respectively, for the Mediterranean population the mean MPOD was 0.42 (CI 95% 0.38‐0.45) and the mean age 39 years old (±17);mean MPOD of this group didn’t seem to change with age (p=0.402) or be affected by gender (p=0.511) either. No statistically significant difference in the MPOD between the two populations was revealed from the analysis (p=0.455). No sex or age effect was observed in the total population (p=0.893, p=0.094 respectively). Conclusion The MPOD was compared between two populations with different levels of light exposure and theoretically different diet. Although these factors are believed to affect the levels of MPOD, the latter didn’t seem to differ significantly between the two groups in the present study. Additionally, the MPOD levels weren’t found to change with age in either group or in the total population. Similarly, no sex differences were observed.
Verteporfin encapsulated in cationic liposomes as an alternative drug for PDT
Authors: RANJBAR M , MARTIN G , AGOSTINI HT 
Published: September 2009

Abstract Purpose Cationic liposomes bind specifically to activated endothelial cells like tissue affected by inflammation. They can be loaded with various drugs and are used as a drug carrier system to reach a locally higher concentration of the drug. We used photodynamic therapy (PDT) to compare the established verteporfin (Visudyne®) with cationic liposome‐bound verteporfin (Lipovert) in laser‐induced choroidal neovascularization (L‐CNV) of mice. Methods Cationic liposomes were loaded with verteporfin (resulting in Lipovert). C57BL/6 mice underwent Argon laser coagulation on day 0 (d0). Lipovert or verteporfin were injected into the tail vein on d10. The CNVs were irradiated with non‐thermic red light (689 nm) 1 min (verteporfin) or 60 min (Lipovert) after injection as pre‐experiments showed the accumulation peak of the drugs during that time. Animals were perfused with FITC‐dextran at d12, d14 or d17. Choroido‐scleral flat mounts were prepared for quantification of the CNV by measuring the area of FITC‐dextran positive vessels. Results The mean CNV areas of mice treated with Lipovert or verteporfin were clearly reduced to about half of the control. Lipovert was slightly more effective than verteporfin. Conclusion In our experiments, Lipovert can be substituted for verteporfin. Therefore, it has the potential as a drug for photodynamic therapy. As Lipovert accumulates specifically at the sites of activated endothelial cells, it may show less side effects.
Quantification of neuronal cells in healthy rat retinas by flow cytometry
Authors: TSOKA P , PAPADAKI E , PALLIKARIS IG , TSILIMBARIS M 
Published: September 2009

Abstract Purpose The primary purpose of this study was to evaluate the potential to quantify the different neuronal populations in the retina of healthy Sprague–Dawley rats in an accurate quantitative way by using flow cytometry. Methods Rats were killed and the eyes were enuclated to achieve retinal dissection. Tissue dissociation was accomplished with trypsin. After trypsin action was blocked the cells were mechanically dissociated into a single‐cell suspension by gentle pippeting. The cells were permeabilized and stained with the primary antibody. This incubation was followed by another one with a blocking antibody and finally the cells were incubated with the secondary antibody. At least 100.000 healthy cells were analyzed with a FACScalibur and FlowJo software. Dead cell and cell debris were exluded from analysis by gating with forward scatter and side scatter as indicators. The primary antibodies were anti‐rhodopsin against photoreceptors, anti‐Protein Kinace C against bipolar cells, anti‐calbindin against horizontal cells and anti‐microtubule associated protein 1 against ganglion cells. All the primaries antibodies were monoclonal and the secondary antibody was goat anti‐mouse Alexa Fluor 594. Results Quantification of the above populations was possible using flow cytometry. In this preliminary study, the photoreceptors had the 53.99%, the ganglion the 7%, the bipolars the 4% and the horizontal the 1.15% in the hole mixed retinal population. All experiments were repeated six times. Conclusion Flow cytometry can be used to quantify the different neuronal populations in control healthy eyes and this verification will be very useful in future in studies in apoptosis or proliferation of these cells.
Role of HSP70 and p62 in regulation of autophagy clearance in ARPE‐19 cells
Authors: KAARNIRANTA K 
Published: September 2009

Abstract Purpose A hallmark of RPE cell aging is lysosomal lipofuscin accumulation reflecting a weakened capacity for protein degradation in lysosomes. The presence of lipofuscin increases the misfolding of intracellular proteins, which evokes additional stress in the RPE cells. If the capacity of molecular chaperones to repair protein damages is overwhelmed, then the proteins are mainly cleared in proteasomes or in lysosomes including autophagy. We demonstrate that autophagy is a master clearance mechanism in proteasome inhibitor ‐induced aggregation in ARPE‐19 cells. Methods The HSP70, p62 and ubiquitin expression levels and localization were analyzed by western blotting and immunofluorescense. Confocal and transmission electron microscopy were used to detect cellular organelles and to evaluate morphological changes. HSP70 and p62 levels were modulated using RNA interference and overexpression techniques. Cell viability was measured by colorimetric assay. Results The proteasome inhibitor MG132 evoked the formation of juxtanuclear protein aggregates in ARPE‐19 cells. It also caused a robust accumulation of HSP70 and p62 proteins and ubiquitin‐protein conjugates that all colocalized with the formed protein aggregates. We found that protein aggregation is a temporary process, a cessation of proteasome inhibition led to autophagosome‐mediated removal of cytoplasmic protein aggregates. Interestingly, the p62 rather than the HSP70 regulate autophagy activity. However, both of them have essential function in regulation of cellular viability. Conclusion In addition to classical lysosomal proteolysis, there is the increasing evidence that heat shock proteins, proteasomes and autophagy regulate protein turnover in the RPE cells and thus have important roles in AMD disease.
Intravitreal bevacizumab for choroidal neovascularization secondary to angioid streaks: one year follow‐up
Authors: KORT F , BOURAOUI R , CHEBIL A , CHAKER N , CHAABOUNI A , MGHAIETH F , EL MATRI L 
Published: September 2009

Abstract Purpose To evaluate the efficay and safety of intravitreal bevacizumab at one year follow‐up, for the treatment of choroidal neovascularization (CNV) associated with angioid streaks. Methods Consecutive series of 16 eyes with subfoveal or juxtafoveal CNV secondary to angioid streaks, treated with intravitreal bevacizumab (1.25 mg in 0.05 ml) between January 2007 and March 200, were reviewed retrospectively. Ophthalmic examination including best corrected visual acuity (BCVA), optical coherence tomography (OCT) and fluorescein angiography, was performed before and after treatment. Retreatment was given every six weeks in case of persisting symptoms or CNV activity on OCT. The main outcome measures were changes in BCVA and central retinal thickness on OCT at the 1‐year follow‐up. Results The mean number of injections was 4.6 at one year. Ten eyes (62.5%) received more than five injections. The mean BCVA at baseline was 20/81 (range 20/400 to 20/32) and improved to 20/40 (range 20/100 to 20/20) at one year (p=0.055). The BCVA improved by three or more lines in ten eyes (62.5%) and remained within two lines of baseline in six eyes (37.5%). Mean central retinal thickness was 404.2µm at baseline (range 160 to 602 µm) and decreased to 293.3µm (range 150 to 490µm) at one year (p=0.006). No ocular or systemic complications were noted. Conclusion The one‐year outcomes suggest intravitreal bevacizumab to be a promising treatment for CNV associated with angioid streaks, resulting in both functional and anatomical improvements. Repeated injections are needed to maintain these results.Further controlled, prospective and long term evaluations of this treatment are warranted.
TNFα suppresses IFNγ‐induced MHC Class II expression in retinal pigmented epithelial cells by down regulating Class II trans‐activator mRNA
Authors: MAKHOUL M , BRUYNS C , KOCH P , CASPERS L , WILLERMAIN F 
Published: September 2009

Abstract Purpose The expression of MHC class II molecules induced by IFNγ on RPE cells plays a crucial role in the development of autoimmune uveitis. As TNFα is commonly coexpressed with IFNγ in this disease, we have investigated the effects of TNFα on the IFNγ mediated MHC II induction in RPE cells. Methods ARPE‐19 were cultured and stimulated with TNFα, IFNγ, IL‐1β and different combination of these cytokines. After cytokine treatment, we have analysed the expression of MHCII and ICAM‐1 by flow cytometry. IDO induction was studied by Western blotting. The activation and expression of two proteins involved in IFN pathway: IRF1 and STAT was analysed by Western blot. We have also monitored the effects of TNFα and IFNγ on the expression of CIITA by quantitative RT‐PCR. Results TNFα, but not IL‐1, inhibits IFNγ induced MHC class II expression on the surface of ARPE cells. We did not observed an inhibitory effect of TNFα on the expression of ICAM and IDO induced by IFNγ. Similarly, STAT1 phosphorylation and IRF1 induction obtained after IFNγ treatment were not affected by TNFα. On the contrary, we found that TNFα suppresses IFNγ induced CIITA mRNA accumulation. Conclusion TNFα suppresses IFNγ induced CIITA mRNA accumulation and MHC II expression in human retinal pigment cells.
Comparative assessment of S. aureus microbial biofilm inhibition by an N‐alkyl‐polyethyleneimine covalently attached to PMMA or titanium in the Boston Keratoprosthesis
Authors: BEHLAU I , MUKHERJEE K , TODANI A , KLIBANOV AM , GILMORE MS , DOHLMAN CH 
Published: September 2009

Abstract Purpose Biofilms are matrix‐associated microbial communities adherent to either biological surfaces or abiotic surfaces. They account for the majority of device‐associated infections. Our goal herein is to minimize bacterial adherence and biofilm formation by comparative analysis of new polycations bound to bio‐prosthetic ocular‐associated materials, poly (methyl methacrylate) (PMMA) or titanium, using the Boston KPro as a model system. Methods Using S.aureus ocular‐associated clinical isolates, a quantitative assessment of microbial biofilm formation by linear N,N‐dodecyl,methyl‐polyethyleneimine (DMPEI) (217 kDa) covalently bound to PMMA or titanium compared to the parent PMMA or Ti, respectively, has been performed using confocal laser scanning and electron microscopies. In addition, DMPEI‐bound materials have been screened for corneal toxicity in both cell tissue culture and rodent models, and as compared to the original materials. Results A marked inhibitory effect in S. aureus biofilm formation on DMPEI‐derivatized materials compared to the parent PMMA (3‐4 fold) and Ti (2‐fold), without conferring additional epithelial cell cytotoxicity in vitro, has been observed. Furthermore, we have found no additional tissue reactivity, and possibly even a protective effect, with DMPEI‐derivatized materials in vivo. Conclusion We found that covalent derivatization with DMPEI of PMMA and Ti greatly reduces S. aureus biofilm formation in vitro compared to the parent materials. There was no additional cytotoxicity seen both in vitro and in vivo. Future studies will evaluate DMPEI‐derivatized materials for in vivo antimicrobial efficacy.
Macular edema and neovascularization in a case of Stargardt macular dystrophy
Authors: KARAMPATAKIS V , VOUTAS S , LAKE S , KORDALI P 
Published: September 2009

Abstract Purpose To present a case of macular edema and neovascularization in a patient who was diagnosed with Stargardt macular dystrophy. Methods We present the case of a 22 year old male who experienced visual deterioration in his left eye. At presentation his visual acuity was OD 8‐9/10 and OS 6‐7/10. OCT scan, fluoroangiography (FA) and electroretinografy (ERG), were performed. Results OCT scan revealed cystoid macular edema in the right eye, and increased reflectivity of the pigment epithelium and some subretinal fluid in the left eye. FA findings were consistent with Stargardt dystrophy. However in the right eye an area of increasing hyperfluorescence was observed (presence of neovascularisation). ERG: subnormal photopic and scotopic responses. The color vision was impaired mainly in the left eye. Following the experience of other investigators acetazolamide was administered orally (300 mg per day) and resolution of the cystoid edema was obvious in OCT scan after 20 days. The visual acuity increased (OD 10/10 and OS 8/10). Two weeks after the discontinuation of acetolozamide the macular edema reappeared and the visual acuity diminished: OD 8‐9/10 and OS 6‐7/10. Conclusion This is a peculiar case of cystoid macular edema and neovascularization in Stargardt macular dystrophy. Our findings suggest, in consistency with other investigators, that administration of oral acetozolamide may be beneficial for the resolution of macular edema. The neovascularization in the left eye remained stable during the follow up period and it was considered that any intervention was not necessary at that time.