bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship between IOP and age in the Salzburg‐Moorfields‐Collaborative Glaucoma Study
Authors: REITSAMER HA , HITZL W , WINTERSTELLER CH , HORNYKEWYCS K , ABRI S , GRABNER G
Published: September 2009

Purpose To investigate the distribution of intraocular pressure in a population based survey in the county of Salzburg.

Methods The SMCGS is a single‐center, prospective cohort study embedded into a government supported glaucoma blindness prevention program in Salzburg county, Austria. A complete ophthalmological examination including biomicroscopy of the optic nerve head, visual field testing, measurements of intraocular pressure, central corneal thickness and laser scanning topography of the optic disc was performed on 3650 subjects at the beginning of the study as well as at the five year follow‐up.

Results The average age is 60.3 years (min: 40.04, max:93.9 years), IOP is 15.0 mmHg (min: 7, max: 32 mmHg) and the correlation coefficient between age and intraocular pressure is r = 0.005, p = 0.75 (95% CI ‐0.03 and 0.026). Also in the subgroups (people with normal findings, people with increased cup to disk ratio (C/D>0.45) and people with ocular hypertension (IOP>21mmHg) no significant correlation between age and intraocular was found.

Conclusion In the past, numerous studies showed a correlation between age and intraocular pressure or at least reported a vague relationship between the two variables. Of all large scale studies only the blue mountain eye study and the Beijing eye study did not find a positive correlation between age and intraocular pressure (before correction for arterial pressure). In the population of Salzburg, age is an independent risk factor for glaucoma, independent of IOP and without correction of possible confounders.
Association between optic nerve head blood flow as assessed with Laser Doppler Flowmetry and mean arterial blood pressure in glaucoma, ocular hypertension and healthy control subjects
Authors: SCHMIDL D , HOMMER A , RESCH H , FUCHSJAEGER‐MAYRL G , GARHOFER G , VASS C , SCHMETTERER L
Published: September 2009

Purpose It has been implicated that vascular dysregulation plays a role in the pathogenesis of primary open angle glaucoma (POAG). In the present study the association between optic nerve head blood flow as measured with laser Doppler flowmetry and ocular perfusion pressure in patients with treated and untreated POAG, patients with ocular hypertension and healthy control subjects was compared.

Methods 136 patients with treated POAG, 116 patients with untreated POAG, 138 patients with ocular hypertension and 160 control subjects were included in the study. Optic nerve head blood flow was assessed using laser Doppler flowmetry. Ocular perfusion pressure was calculated based on measurement of IOP and systemic hemodynamics.

Results Optic nerve head blood flow was significantly reduced in patients with glaucoma compared to patients with ocular hypertension and healthy subjects (p<0.01). However, no difference in optic nerve head blood flow between treated and untreated glaucoma patients was detected. The highest association between ocular perfusion pressure and optic nerve head blood flow was found in untreated glaucoma patients followed by ocular hypertensives and treated glaucoma patients.

Conclusion The present study confirms evidence that optic nerve head blood flow is reduced in patients with POAG and patients with ocular hypertension. Correlation coefficients in the glaucoma groups and in the ocular hypertensives indicate a vascular dysregulation in these patients compared to healthy control subjects.
Vascular endothelial dysfunction in primary open angle glaucoma
Authors: CELLINI M , GIZZI C , STROBBE E , FAVARETTO E , FILIPPINI M , PALARETI G , CAMPOS EC
Published: September 2009

Purpose Glaucomatous optic neuropathy (GON) is related not only to elevated intraocular pressure (IOP) but also to an insufficient ocular blood supply related to a vascular dysregulation. We evaluated peripheral vascular endothelial function in primary open‐angle glaucoma (POAG) with a non‐invasive endothelium flow mediated vasodilatation (FMD).

Methods We studied 20 POAG patients. The diagnostic criteria for POAG was an IOP exceeded 22 mm/hg before treatment, open anterior chamber angle, cup/disc ratio >0.7 and optic nerve related visual field loss (MD>6 dB, SF>2.5 dB and CPSD>3 dB). Patients with systemic diseases such hypertension, heart failure and diabetes mellitus were excluded. All patients and 20 normal controls underwent measurement of FMD with high‐resolution 2‐dimensional ultrasonographic imaging of the brachial artery by a Philips ENVISOR echographic machine. To induce iperemia a sphygmomanometer cuff was inflated to 250 mm/hg for 5 minutes. The cuff then was deflated rapidly and at 60 seconds after cuff deflation 2‐D images of the brachial artery were recorded for 5 seconds. A statistical analysis was made of the FMD in POAG and in normal control patients using the Student “t” test for unpaired data and the Pearson correlation test to show the correlation between the endothelial dysfunction and the visual field indexes.

Results Patients affected by POAG exhibit lower values of FMD compared with healthy people In POAG patients we found an FMD 4,28%±2,49 vs. 8,66%±3,02 (p<0.001). The mean decrease (MD) visual field index was related to FMD (p<0.05).

Conclusion Patients with POAG have an impaired vascular function related to a vascular endothelium dysfunction and the MD visual field is related to FMD impairment.
Measurement of IOP with radiowave telemetry
Authors: TODANI A , FAVA M , BEHLAU I , MELKI S , DOHLMAN CH
Published: September 2009

Purpose To illustrate the implantation technique & tolerance of a novel wireless silicone‐encased intraocular pressure transducer in rabbit eyes. The device can conceivably provide a reliable way to measure the IOP in situations where measurement is difficult with the present technology, for instance in eyes with keratoprosthesis implants.

Methods The transducer, manufactured by Mesotec GmbH (Hannover, Germany), is a fully digital ultra miniature system, integrating pressure sensing, data handling and telemetry on a single microchip. The microchip is connected to a telemetry coil and requires no internal power source. The data is received using an external reader unit. The transducers were initially tested for calibration in enucleated bovine eyes. They were sterilized with ethylene oxide. They were implanted either through a corneal autograft (n=2) or through a large limbal incision (n=2) and placed either in the sulcus (n=2) or suspended into the vitreous cavity (n=2) after removing the crystalline lens. In one rabbit (SHAM), the crystalline lens was removed but no implant was placed. The eyes were closed with interrupted 10‐0 nylon sutures. Daily observations and weekly full clinical examinations were performed. The readings obtained by the transducer‐readers were compared with those obtained by Tonopen.

Results The transducers were well tolerated, with minimal transient post‐operative intraocular inflammation that was similar in both the experimental and SHAM groups at comparable time‐points. The pressure obtained by the transducers showed good correlation with those obtained by Tonopen.

Conclusion Our animal studies show that the transducer can be easily implanted and is well tolerated inside the rabbit eye, up to 4 months at the present time.
Retinal oxygenation in diabetic retinopathy
Authors: HARDARSON SH , OLAFSDOTTIR OB , KARLSSON RA , BEACH JM , EYSTEINSSON T , BENEDIKTSSON JA , STEFANSSON E
Published: September 2009

Purpose Diabetic retinopathy (DR) is believed to cause retinal tissue hypoxia by damaging retinal capillaries. The purpose of this study was to examine the effect of diabetic retinopathy on oxygen saturation in retinal arterioles and venules.

Methods The retinal oximeter (Oxymap ehf., Reykjavik, Iceland) is composed of a fundus camera, beam splitter and light filters. Specialized software calculates relative oxygen saturation from light absorption at two wavelengths of light (605nm and 586nm). One first or second degree temporal arteriole and venule were measured in one eye of 31 healthy individual and 28 patients with diabetic retinopathy. The diabetic patients had background DR (n=6), macular oedema (n=7), untreated preproliferative or proliferative DR (n=7) or stable proliferative DR after treatment (n=8). Statistical analyses were performed with an unpaired t‐test, one‐way ANOVA and Dunnett's post test.

Results Retinal arteriolar saturation was 93±4% (n=31, mean±SD) in healthy subjects and 101±6% (n=28) in patients with DR (p<0.0001). Retinal venular saturation was 58±6% in healthy subjects and 67±8% in diabetic patients (p<0.0001). Arteriolar and venular saturation was higher in all subgroups of diabetic patients (see methods) than in healthy subjects.

Conclusion Increased oxygen saturation in retinal vessels in diabetic retinopathy, also found by other researchers, is consistent with poor distribution of blood and oxygen to the retinal tissue rather than decreased total retinal blood flow. Poor distribution of oxygen may be caused by capillary dropouts and shunts as well as thickening of the capillary walls.

Commercial interest
Retinal vessel oximetry made simple and reliable ‐ principle, performance and clinical results
Authors: HAMMER M , SCHWEITZER D
Published: September 2009

Purpose The regulation of the oxygen supply to the retinal tissue is critical and the detection of alterations in the oxygen supply or consumption may have a diagnostic merit. Quantitative assessment of oxygen supply and oxygen utilization in the tissue requires the measurement of the blood flow as well as the blood oxygenation. While the blood flow can be calculated from laser Doppler velocimetry and the vessel diameter, the intra‐vascular heamoglobin oxygen saturation (SO2) can be determined by a photometric measurement.

Methods In the current approach, the SO2 is measured by a dual – wavelength technique. Using a fundus camera, equipped with a special dual wavelength transmission filter and a color CCD camera, two monochromatic fundus images at 548 nm and 610 nm were recorded simultaneously. The optical densities of retinal vessels for both wavelengths and their ratio, which is known to be proportional to the oxygen saturation, were calculated. Measurements of SO2 were performed in patients with diabetic retinopathy, arterial occlusion, and healthy controls. Furthermore, the changes of SO2 upon flicker light stimulation of the eye were investigated.

Results From a healthy control population, mean arterial and venous SO2 were measured to be 98±10.1% and 65±11.7% with reproducibility of 2.52% and 3.25% respectively. In 10 patients with central or branch vein occlusion, a reduction of the arterial SO2 to 62±11% was found in the occluded vessel. After 5 days on pentoxifilin therapy, the SO2 increased to 90±16%. Diabetics showed venous SO2 increasing with the severity of the retinopathy. Flicker increased the venous SO2 by about 5%.

Conclusion Dual wavelength oximetry is a simple and reliable method for physiological and clinical investigations.

Commercial interest
Screening history of those with severe visual impairment due to diabetic retinopathy
Authors: HART PM , HART PW , JACKSON AJ
Published: September 2009

Purpose To examine screening activity prior to blind registration due to diabetic retinopathy (DR) in NI. To identify any grading misclassifications and risk factors for blindness in those screened.

Methods Details on all registered blind due to diabetic retinopathy were obtained from the statutory register (SOSCARE). Demographic data (surname, date of birth and sex) were used in any combination to ascertain previous screening within the evolving NI Diabetic Retinopathy Screening Programme. Screening history and clinical chart review formulated the history prior to registration.

Results The prevalence of diabetic blindness amongst the diabetic population was 0.34%.(171 people) 56% were female and the average age was 65.6(SD 15.6). Diabetic maculopathy was cited as the commonest cause ( 83%) with proliferative disease in 17%. 84% had never been screened and were under the care of an eye clinic. 27 people ( 16%) had been screened within the previous 4 years. 22 of these had been discharged from eye clinics post registration. 5 had never attended an eye clinic. 4 of these showed maculopathy on screening and were referred to an ophthalmologist. One person aged 31, diabetic for 20 years, was screened 2 years prior to registration due to PDR. The screening result was given as no retinopathy in either eye. The digital images were reassessed and no change in grade made. Detailed scrutiny of clinical notes revealed a recent history of severe anorexia with insulin used to control weight.

Conclusion Timely referral from screening is required for optimal management, but it must be recognised that vision cannot be maintained in all cases. Risk factor stratification for earlier screening in exceptional circumstances may be wise.

Commercial interest
Needs from residents’ perspective and SOE YO
Authors: KHAWAJA A
Published: September 2009

A resident's training needs are very diverse and include acquiring knowledge to pass exams, clinical skills, surgical skills and business acumen. Modern training programs aim to deliver each of these requirements in a more structured and reproducible format. However, not all these needs are amenable to structure. These challenges will be discussed and the recently introduced training scheme in the UK will be highlighted as an example.
Professionalism and appraisal
Authors: DUA HS
Published: September 2009

Professionalism is defined as the expertness characteristic of a professional person. A true professional encompasses attributes of integrity, honesty, transparency, fairness, trust, respect, dignity, courtesy and ethical behaviour, working within means with insight into limitations, updating knowledge & skills, communicating effectively and others. Professionalism also involves striking a balance between conflicting pressures such as work and life, family and colleagues and saying “yes” and “no”. In short, professionalism is the ability to put all the above together. Appraisal is a two way process in which the appraiser and appraise together, in a non‐confrontational manner identify the needs of the appraise, establish the means of fulfilling those needs and set objectives and timeframes in which to achieve those needs. Achievements are recognised and appreciated, problems and their causes where possible are identified and means of solving them are considered and action points agreed. Appraisal should occur regularly. All necessary information should be gathered beforehand, discussed during the appraisal and goals set for the next appraisal. The next cycle should begin by considering the goals set previously and understanding why some were not met and acknowledging those that were. The whole process should be a positive and constructive experience for the appraise. The individual should have confidence in the appraisal process and look upon it as a process whereby his accomplishments are recognised and where he or she can openly discuss concerns and find answers. A good appraisal benefits the individual and the employing organisation. Unlike ‘assessment’ it does not pass judgement on the individual’s performance but represents a concerted effort to improve performance.

Commercial interest
Symmetry of retinopathy in the NI diabetic retinopathy screening programme NIDRSP
Authors: HART PM , STEVENSON MR
Published: September 2009

Purpose To predict the probable level of retinopathy in an ungradeable image from the retinopathy status in the gradeable fellow eye

Methods Retinopathy is graded within NIDRSP on a well established grading scale ( 0‐6) based on the ETDRS scale. The retinopathy status ( screening grades) was taken from a cohort of 5000 consecutive patients. Inter eye correlations in grading outcome were examined

Results A high degree of symmetry in retinopathy grades was found. At the lower levels of grade the right eye tended to be slightly worse than the left If a retinopathy grade of 0( none ) to 2 ( definite early retinopathy) was found in the right eye If no retinopathy was found in 1 eye ( right or left), the probability of having referable retinopathy in the fellow eye was found to be zero. If moderate non referable retinopathy was found in the right eye, the probability of having referable retinopathy in the left was 8%. If moderate non referable retinopathy was found in the left eye , the probability of having referable retinopathy in the right was 6%. If referable retinopathy was found in the right eye, referable retinopathy was present in the left in 60%. If referable retinopathy was found in the left eye, referable retinopathy was found in the right eye in 46%.

Conclusion At more advanced levels of retinopathy the probability of having sight threatening retinopathy is higher for the left eye than for the right. This should be considered when referring patients in whom the retinal status of one eye is masked by eg media opacities.

Commercial interest
Central corneal thickness and its association with ocular and general parameters in indians. Central India Eye and Medical Study
Authors: JONAS JB , NANGIA V , SINHA A , MATIN A , KULKARNI M
Published: September 2009

Purpose To evaluate the distribution of central corneal thickness and its associations in the adult Indian population

Methods The Central India Eye and Medical Study is a population‐based study performed in a rural region close to Nagpur in Central India and included 4711 subjects (aged 30+ years) out of 5885 eligible subjects. This study was focused on central corneal thickness (CCT) as measured by sonography and it associations. Intraocular pressure was measured by applanation tonometry.

Results CCT measurement data were available for 9370 (99.4%) eyes. Mean CCT was 514±33 mm (median:517 mm; range: 290‐696 mm). In multiple regression analysis, CCT was significantly associated with male gender (P<0.001), higher body mass index (P=0.028), lower age (P<0.001), lower corneal refractive power (P<0.001), and higher anterior chamber depth (P=0.025). CCT was not significantly associated with axial length (P=0.39), lens thickness (P=0.65), refractive error (P=0.12) and cylindrical refractive error (P=0.75). Intraocular pressure readings increased significantly (P<0.001) with higher CCT and higher corneal refractive power

Conclusion Indians from rural Central India have markedly thinner corneas than Caucasians or Chinese. As in other populations, CCT is higher in males. It decreased with higher age and lower body mass index. Intraocular pressure readings were falsely high in eyes with thick corneas and steep corneas. Besides corneal thickness, the anterior corneal curvature has to be taken into account in applanation tonometry. It may hold true particularly after corneal refractive surgery.
N‐Acetyl cysteine (NAC) attenuates neuronal cell death in culture not solely by up regulating glutathione (GSH).
Authors: ABDUL MAJID AS , OSBORNE NN
Published: September 2009

Purpose To show that NAC attenuates GB (glutamate/buthionine sulfoximine)‐induced death to retinal ganglion cells (RGC‐5 cells) in culture by a mechanism that does not solely involve GSH.

Methods Transformed retinal ganglion (RGC‐5) cells grown in culture were exposed to an insult of GB for defined periods. NAC at different concentrations or vehicle was added to the cultures over 24 hours. Reactive oxygen species (ROS) generation was measured using a dye 20,70‐dihydroethidium. Cell death was measured by use of an MTT and resazurin‐assays and evidence for apoptosis was obtained with an APOPercentage™ procedure. Glutathione (GSH), catalase (CAT), gluthathione‐S‐transferase (GST) and superoxide dismutase (SOD) were also determined using a different fluorescent procedure.

Results NAC dose‐dependently attenuated GB‐induced generation of ROS and death by a form of apoptosis to RGC‐5 cells in culture. NAC also independently stimulated the production of not only GSH but also GST, CAT and SOD. Moreover, NAC attenuated GB‐induced loss of intracellular GSH, CAT and GST.

Conclusion NAC significantly blunts oxidative‐induced death to RGC‐5 cells induced by GB. Evidence is also provided to show that NAC increases intracellular GSH, GST, CAT and SOD levels. The neuroprotective action of NAC is therefore complex and is not solely caused by an action on GSH.
Ocular and plasma bioavailability of different memantine formulations after periocular administration
Authors: PRIETO CALVO E , BREGANTE UCEDO MA , PEREZ OLIVÁN S , PUENTE BAYO B
Published: September 2009

Purpose To determine the memantine vitreous and plasma levels after the periocular injection of different types of memantine formulations, saline solution (SS), metylcellulose 0,5% (MC 0,5%) and polyvinylpyrrolidone 1% solution (PVP 1%); by posterior subtenon route.

Methods In vivo experiments were done with albino New Zealand rabbits. Forty five rabbits were used and divided into 3 groups, one for each of the essayed formulations. 4,5 mg of memantine in 0,3 ml of formulation were administrated per animal by periocular injection into the posterior subtenon space, on the right eye of each animal. Plasma (2mL) and vitreous humor samples were obtained at 10, 60, 120, 240, and 1440 minutes post injection. A method with n‐hexane liquid‐liquid extraction and FMOC derivatization was used for the quantitative determination of memantine in the biological samples, using HPLC with fluorescence detection.

Results Just 10 minutes post injection, detectable levels of memantine in plasma and vitreous humor were obtained on each of the 3 groups. Several concentrations of memantine were detected in vitreous from 10 to 1440 minutes when PVP formulation was administered. However, 24 hours post injection, no Memantine levels were detected on treated eyes with SS or MC 0,5% solution. According to plasma similar concentrations of memantine have been obtained for the different types of formulations.

Conclusion After periocular administration, several memantine levels were detected in the vitreous chamber. In our opinion, these concentrations can be higher than after systemic and topic administration. The use of formulations as PVP, which has a higher permanence on the injected area, allows a sustained delivery of the drug.
The effect of betablockers on ocular hemodynamics in anesthetized rabbits
Authors: RUNGE CW , BOGNER B , STROHMAIER C , GRABNER G , REITSAMER HA
Published: September 2009

Purpose To compare the effects of different betablockers on ocular hemodynamics in anesthetized New Zealand White rabbits.

Methods Mean arterial pressure (MAP), intraocular pressure (IOP) and orbital venous pressure (OVP) were measured by direct cannulation of the central ear artery, the vitreous and the orbital venous sinus, respectively. Laser Doppler flowmetry was used to measure choroidal and ciliary blood flow. The performed measurements were made continuously at baseline and after drug application.

Results Metoprolol showed a significant reduction of the choroideal blood flow (‐13,6 ± 1,4%, p = < 0,05) which was not observed in the ciliary body. Atenolol had a similar effect on the choroid with a significant reduction (‐7,3 ± 1,0%, p=< 0,05) and no significant change in the ciliary body. The intravenous administration of Nebivolol produced a decrease of the choroideal blood flow (‐11,2± 0,9%, p=< 0.05) and also no significant change of the ciliary blood flow. In all three series we could detect a clear decrease of IOP and heart rate.

Conclusion All tested betablockers showed vasoconstrictive effects on the choroidea. Although they are different in their nature they showed similar effects by intravenous administration on the examined parameters. A vasodilative effect of nebivolol could not be detected.
Surgical experience and outcome of scleral buckling procedures in retinal detachment
Authors: ARNDT C , FRANCERIE‐SADDIKI V , BRUGNIART C , SEGAL A , DUCASSE A
Published: September 2009

Purpose The purpose of this study was to evaluate the impact of the surgeons' experience on the anatomical and functional outcome of primary scleral buckling surgery in rhegmatogenous retinal detachment.

Methods The charts of patients presenting with a retinal detachment between 2000 end 2006 were analyzed retrospectively. All patients with macular involvement treated with scleral buckling surgery were included. The surgeons were designated according to the “on call” list. Junior surgeons were fellows with less than 2 years of experience, physicians with more than 2 years of experience were defined as senior surgeons.

Results Among the 115 included patients, 76 (65,8%) were operated by senior surgeons. The age, duration of symptoms, initial visual acuity, extension of the retinal detachment were similar in both groups. The primary reattachment rate was 87,7% in the senior surgeon group versus 92,1% in the junior surgeon group (p=0,36). In the eyes operated by senior surgeons, the final visual acuity was better than 20/40 in 78,5% versus 63,2% in eyes operated by junior surgeons (p=0,09).However, in phakic eyes with limited retinal detachments, the senior surgeons achieved better functional results (p<0.01).

Conclusion The surgical experience, except in some subgroups of patients, did not significantly influence the anatomical or the functional overall outcome of patients undergoing primary scleral buckling surgery in retinal detachment with macular involvement.
First experience with The IRIS retinal implant system
Authors: VELIKAY‐PAREL M , IVASTINOVIC D , LANGMANN G , HORNIG R , GEORGI T , WEDRICH A
Published: September 2009

Purpose To report on the first 4 months experience of a patient with the active IRIS‐ Implant.

Methods 4 weeks after implantation the training with the active implant started. Thresholds were measured at each training day. Light perception, light localisation, point to point discrimination and motion detection were measured with special test procedures. Visual function training was performed.

Results Visual perception was achieved, when the stimuli were generated by the computer and with the camera mode. All tests were successful.

Conclusion Successful stimulation and major improvements during the training demonstrates that with the Iris Implant System a visual perception can be achieved, which is relevant for daily life.
Pre‐receptoral spectral absorption, healthy ageing and pre‐clinical indications of retinal disease
Authors: KONSTANTAKOPOULOU E , BARBUR J
Published: September 2009

Purpose The aim of this study was to investigate how chromatic sensitivity changes as a function of age and to establish the extent to which such changes can be attributed to pre‐receptoral spectral absorption of short wavelength light and/or changes in retinal mechanisms caused by ageing.

Methods The absorption of blue light by the macular pigment (MP) and the crystalline lens and the subjects’ sensitivity to rapid flicker were measured using the Macula Assessment Profile (MAP) test. Red‐green (RG) and yellow blue (YB) chromatic detection thresholds were measured at the fovea for young and older subjects using the Colour Assessment and Diagnosis (CAD) test at 2.6, 26 and 65 cd/m2. The variables of interest included the spectral absorption of the lens, the optical density of the MP, subject’s age and retinal illuminance.

Results The absorption of blue light by the lens increased with age. Absorption of blue light by pre‐receptoral filters did not affect RG chromatic sensitivity at any of the light levels investigated but had an effect on YB thresholds. The considerably higher colour vision thresholds of some subjects and the subsequent worsening of their chromatic sensitivity at the lower light level may reflect changes in the retina brought about by accelerated aging effects.

Conclusion The effect of pre‐receptoral absorption of blue light on chromatic sensitivity is small. Ageing affects the amount and spectral composition of the light reaching the photoreceptors and the processing of retinal signals. As a result, flicker sensitivity declines and colour vision deteriorates. Such effects arise mostly from changes in the retina. The MAP and CAD tests help us to detect the effects of accelerated ageing and retinal disease.
Detection of osmoprotective effect of topical compatible solutes on ocular surface epithelia
Authors: CALIENNO R , NUBILE M , LANZINI M , CURCIO C , COLESANTE M , CIAFRE M , MASTROPASQUA A
Published: September 2009

Purpose Inflamation and hyperosmolarity play an important role in generating dry‐eye related damage on the ocular surface. A new approach is the use of topical compatible solutes (CS) to induce osmoprotective effect on ocular surface epithelia. Aim of this study was to evaluate the osmoprotective action of topical CS on ocular surface in dry‐eye patients.

Methods We evaluated 48 eyes of 24 dry‐eye patients, current users of artificial tears. At baseline they underwent impression cytology (IC) and immunoflurescence staining to detect expression of inflammatory cytokines linked with hyperosmolarity in ocular surface epithelia. In vivo confocal microscopy (IVCM) of corneal and conjunctival surface was performed and epithelial morphology and inflammatory cells infiltration were evaluated. Patients started topical treatment with methilcellulose and CS in one randomly selected eye, while the fellow eye continued previous eye drops.IC and IVCM were performed after 30,60 and 90 days.

Results At baseline IVCM and IC results were comparable in both eyes . At 90 days IVCM showed a significant improvement in epithelial regularity in treated eyes while in control group no significant changes were observed.IC evidenced a significant reduction of inflammatory cytokines between baseline time and day 60, stable till the end of follow‐up, while in control group no significant changes were observed.

Conclusion The use of topical CS can improve epithelial regularity and reduce ocular surface inflammation in dry‐eye syndrome.
Loss of thioredoxin activity as an important contributor to oxidative stress in lens of diabetic rats
Authors: LOU M , LECHNER J , XING K , KADOR PF
Published: September 2009

Purpose Thioredoxin (Trx) is a redox regulator whose bioavailability in mammalian tissues is regulated by its intrinsic binding protein, thioredoxin‐binding protein‐2 (TBP‐2). The purpose of this study is to investigate whether diabetic condition can alter the ratio of Trx and TBP‐2 expressions in the lens that may contribute to cataract formation.

Methods Streptozotocin (STZ at 75 mg/kg) induced diabetic rats were divided into aldose reductase inhibitor (0.0125% AL1576) treated and untreated groups. Rats without STZ injection were used as controls. Lenses from 3 and 8 wks post STZ injection were used to determine GSH level, Trx activity, and Western blot analysis for Trx and TBP‐2 protein levels.

Results The lenses in the diabetic untreated group showed slight haziness in 3 wks, and moderate to severe opacity in 8 wks while all lenses in the ARI‐treated or control groups remained clear in both ages. The untreated diabetic group showed severe loss in GSH (< 20% of control in both 3 and 8 wks) and Trx activity (< 35% of the control in both 3 and 8 wks). TBP‐2 expression although was unchanged at 3 wks but elevated ~4‐fold over the control in 8 wks while Trx expression remained constant at both time points. ARI treatment protected the GSH level, Trx activity, and TBP‐2 expression in these lenses.

Conclusion Diabetic condition induced TBP‐2 expression in the lens with concurrent suppression of Trx activity. The results suggest that the loss of the bioavailability of TRx, in conjunction with a severe GSH depletion, is likely to contribute to the oxidative stress observed in diabetic conditions. Furthermore the observation that ARI can normalize these changes suggests a role of osmotic stress in Trx/TBP‐2 imbalance.
Treating diabetic dogs with topical KinostatTM for cataracts: proof of concept clinical trial
Authors: KADOR PF , ROBBIN‐WEBB T , BRAS D , KETERING KL , WYMAN M
Published: September 2009

Diabetic dogs rapidly form bilateral sugar cataracts within one year of diagnosis. Similar sugar cataracts also form in galactose‐fed dogs. Since topical KinostatTM has been shown to reverse initial cataract formation in young galactose‐fed dogs, we have conducted a proof of concept masked pilot study with 41 newly diagnosed dogs with diabetes mellitus (DM) to investigate whether KinostatTM can inhibit the progression of cataracts in a clinical setting. After obtaining owner consent to participate in the study, all dogs were randomly assigned a coded vial containing either KinostatTM or vehicle for 1 year with the contents of the vial (drug or placebo) masked from the examiners. Thirty dogs received the active agent while the remainder received the placebo vehicle. Owners were instructed to administer the agent 3 times daily to both eyes and compliance was monitored by recording each time of administration. Ocular examinations on dilated eyes conducted at the initial examination and at 1, 2, 3, 6, and 9 month intervals with slit lamp and indirect ophthalmoscopy indicated that KinostatTM is beneficial in arresting the onset and/or progression of cataracts in dogs with DM. The implications of this study for human sugar cataracts will also be discussed. Supported by NIH SBIR 1R43EY018013‐01A1

Commercial interest
Anticataract effect as a predictor of drug efficacy against early diabetes‐induced retinal changes
Authors: OBROSOVA IG
Published: September 2009

Purpose To evaluate if anticataract effect predicts drug efficacy against early diabetes‐induced retinal changes, using STZ‐diabetic rat model and cultured retinal microvascular cells.

Methods Mature control and STZ‐diabetic rats received one of the following treatments (a prevention approach): 1) the aldose reductase inhibitor (ARI) fidarestat, 2) the PARP inhibitors, 1,5‐isoquinolinediol or GPI‐15427; 3) the Na+/H+‐exchanger‐1 (NHE‐1) inhibitor cariporide; and 4) two agents, counteracting endoplasmic reticulum stress,trimethylamine N‐oxide dehydrate or 4‐phenylbutyric acid. The duration of diabetes was 12 wks. Cataract formation was monitored by indirects ophthalmoscopy and slit lamp examination.Oxidative stress and apoptosis were assessed as early diabetes‐induced retinal changes in rat retinae and cultured bovine retinal pericytes and endothelial cells.

Results An ARI treatment completely prevented cataract formation in STZ‐diabetic rats, whereas three other treatments delayed, but did not prevent, diabetes‐induced cataractogenesis. All four classes of agents counteracted diabetes‐induced apoptosis in rat retinae, and the ARI, PARP inhibitor, and NHE‐1 inhibitor treatments prevented high glucose and NEFA‐induced apoptosis in pericytes and endothelial cells. Fidarestat, PARP inhibitors, and cariporide treatments also counteracted diabetes‐related oxidative stress in the retinae and cultured retinal microvascular cells. The effect of agents counteracting endoplasmic reticulum stress on retinal oxidative stress has not been explored.

Conclusion Anticataract effect ia a likely predictor of the efficacy of experimental pharmacological agents against, at least, early diabetes‐associated retinal changes which may facilitate diabetes drug discovery.

Commercial interest
Comparison of the visual response to corneal enhacement on femtosecond and microkeratome created flaps.
Authors: CANADAS SUAREZ P , IBARZ‐BARBERA M , HERNANDEZ ‐VERDEJO J , TEUS M
Published: September 2009

Purpose To evaluate the evolution of visual acuity after enhacement after LASIK performed either with a mechanical microkeratome (MM) or femtosecond laser (FS), up to the third month post‐op.

Methods Retrospective analysis of 148 consecutive eyes who had LASIK, 125 with femtosecond laser (intralase) and 123 with a mechanical microkeratome (Moria M2), had an enhacement performed between the third and the sixth month post‐op. All the surgeries were performed by the same surgeon. All the patients were examined preoperatively, 24 hours, 7 days, one month and three months after the enhancement.

Results Both groups had good visual outcomes with no significant differences in visual acuity at the third month. The uncorrected visual acuity (UCVA) was 1.02±0.2 in both groups (p=0.9), the best corrected visual acuity (BCVA) was 1.07±0.1 and 1.09±0.1 for the FS and the MM groups respectively. The safety (1.02±0.1 in the FS group, 1.03±0.1 in the MM group, p=0.7) and efficacy (0.97±0.1 and 0.95±0.1 for the FS and MM respectively, p=0.4) were similar in both groups. Neverthelerss we found a statistically significant difference on UCVA on the first week (0.93±0.1 femtosecond vs 0.98±0.1 microkeratome, p=0.01).

Conclusion Visual acuity recovery is slower after enhacement on FS flaps only on the early postoperative period. Probably, there is an increased epithelial damage or a superior inflammatory response due to a more difficult flap‐lifting in FS vs a MM cases.
Microplasmin improves surgical outcome in a rabbit model for trabeculectomy
Authors: VANDEWALLE E , VAN BERGEN T , YOU Y , VAN DE VEIRE S , MOONS L , STALMANS I
Published: September 2009

Purpose This study was designed to study the efficacy and safety of Microplasmin as an anti‐scarring agent after trabeculectomy in a rabbit model.

Methods The effect of Microplasmin was investigated in vivo in a rabbit model for glaucoma surgery. Clinical outcome measures were intra‐ocular pressure, bleb area and survival, side effects on slit lamp examination. Moreover, (immuno‐) histochemical analysis of the eyes was performed, with quantification of inflammation (CD 45) and collagen deposition (Trichrome and Sirius Red). In the first experiment (n=10), Microplasmin anterior chamber injection was compared to placebo injection. In the second experiment (n=3), topical Microplasmin drops were compared to placebo drops. In the third experiment (n=5) the combination of Microplasmin anterior chamber injection and topical drops was compared to placebo injection and drops. All experiments were conducted in a masked observator way.

Results Microplasmin significantly augmented the bleb area and survival in a rabbit model of trabeculectomy after a single anterior chamber injection or combination therapy (injection combined with drops) compared to control. Collagen deposition was borderline reduced after Microplasmin administration compared to control. No significant changes in inflammation were noticed in the anterior chamber or in the conjunctiva.

Conclusion Microplasmin single injection or combination with postoperative drops improved the outcome after trabeculectomy. In a rabbit model, larger blebs were produced for a longer period compared to control, and collagen deposition tended to decrease in this small series.
Do patients with normal tension glaucoma have a thinner conjunctiva?
Authors: VAN GINDERDEUREN R , STALMANS I , SPIELBERG L , ZEYEN T
Published: September 2009

Purpose The central cornea is thinner in patients with normal tension glaucoma (NTG). We had developed the surgical impression of thinner conjunctivas in patients with NTG. The purpose of this study was to determine whether there is a difference between the conjunctival thickness of patients with NTG and those with high tension primary open‐angle glaucoma (POAG).

Methods In this prospective study, 40 patients scheduled for trabeculectomy were categorized into NTG and POAG based on maximum intraocular pressure (IOP) as measured by Goldmann applanation tonometry. Ten (10) patients with NTG (max. IOP≤21mmHg) and 30 patients with high tension POAG (max IOP>21mmHg) were included in the study. Conjunctival biopsies taken from the inferior fornix one month prior to trabeculectomy were fixed in formalin and embedded in Historesin. The conjunctival thickness was measured on a standardised way and compared between the two groups. Non‐paired Student T test for two‐tailed groups with equal variance was used for statistical analysis.

Results The difference in mean conjunctival thickness between patients with NTG (66.4μ±21.1) and patients with high tension POAG (104.6μ±44.3) was statistically significant (P=0.045). The mean CCT in NTG (537,6±19.6) was lower than in POAG (548.3±38.0), but did not reach significancy in this study.

Conclusion Patients with NTG have a thinner conjunctiva than those with high tension POAG
Ocular neuromyotonia
Authors: BOSCHI A
Published: September 2009

Ocular Neuromyotonia (ONM) is rare disorder characterized by intermittent diplopia, lasting minutes or seconds, provoked by brief, episodic contraction of muscles supplied by the oculomotor, trochlear, or abducens nerve. These episodes are induced by change in the gaze direction or after holding eccentric gaze. Previous radiation therapy of the sellar or parasellar regions is the most frequent cause. Long standing compression of the oculomotor nerve, by tumor, supraclinoid aneurysms, arachnoiditis, basilar artery dolichoectasia, and others have been reported. Although the exact pathogenesis of ONM is still unknown, there is wide acceptance of the segmental demyelination hypothesis.This presentation will review the clinical presentation, discuss diagnosis work‐up as treatment options.
Visual fields after refractive surgery
Authors: DEMESTICHA A , GINIS H , KYMIONIS G , ASTIRAKAKIS N , PALLIKARIS IG
Published: September 2009

Purpose Laser correction of ametropias is achieved by changing the radius of curvature of a central portion of the cornea. Although current refractive laser technology allows relative uniform correction across an optical zone larger than the scotopic pupil it must be kept in mind that centration of the ablation pattern pertains only to objects on the line of sight. Off‐axis objects are imaged not only through the corrected portion of the cornea but additionally through a meniscus of paracentral cornea involving the transition zone as well as untreated cornea. It was the purpose of this study to investigate the role of this optical effect in the peripheral visual fields in patients undergoing photorefractive keratectomy.

Methods Twenty one eyes of thirteen patients were evaluated before and 3 months following PRK for the correction of myopia (average: ‐3.4D, SD:2.4D) at an optical zone of 6.5mm with the Allegretto 400 Excimer laser. Evaluation of the optical fields was made using the MEDMOND M700 visual fields analyzer using a full threshold procedure. Measurements were performed under cycloplegia while in all cases the subjects were corrected for the distance of the stimulus (+3 D)

Results The detection threshold exhibited a decrease ranging from 0.5 to 9 dB (mean:1.5 dB, SD:2.5) for the periphery of the optical field (30 to 40 degrees). This change was statistically significant (p=0.00628). No statistically significant difference was observed for the central visual field (0‐22 degrees).

Conclusion The loss of peripheral visual fields following refractive surgery may be attributed to the deteriorated retinal image quality in the peripheral visual field. A mathematical model of this reduction is proposed
Reliability and interobserver variability of non‐invasive tear film parameters
Authors: KOSINA‐HAGYO K , VERES A , FODOR E , LANG ZS , CSAKANY B , NEMETH J
Published: September 2009

Purpose To summarize our experiences with a non‐invasive tear interference device.

Methods in thirty‐seven subjects, we measured non‐invasive tear break up time (NIBUT) three times, pictured the lower tear meniscus height (TMH) and the tear film lipid layer pattern five times after complete blinks with Keeler Tearscope Plus. Three independent observers evaluated the photos. Additionally, the lipid pattern was graded by the observers with real‐time examination in thirty‐one subjects. We analysed the repeatability of the tear parameters after different blinks, and the agreement between the observers on assessments of the photos and real‐time examination.

Results The results measured after different blinks did not show significant differences in case of any tear film parameters. The intraclass correlation coefficient (ICC) with 95% confidence interval of NIBUT and mean TMH were 0.605 (0.428‐0.754) and 0.901 (0.848‐0.942), respectively. There was significant difference between the measured TMH of the observers (p<0.001). The results showed significant correlations (r≥0.912, p<0.001), but the standard deviation of the three measured TMH was meanly 11.13% of the mean of them. The graded lipid patterns of observers showed significant differences (p=0.01) in case of photos, but did not (p=0.137) during real–time examination.

Conclusion The Tearscope Plus is a useful tool of non‐invasive tear film examination. However, the evaluation of the parameters is partly subjective, which reduces the reliability of the methods. The real‐time examination of lipid pattern is recommended, because the kinetics of lipid layer allows additional information for grading, therefore decreasing the interobserver variability.
Protein screening in vitreous samples of patients with retinal vein occlusion
Authors: AGOSTINI HT , MARTIN G , HANSEN LL
Published: September 2009

Purpose The aim of the study was to identify proteins involved in the pathogenesis of retinopathy after retinal vein occlusion. In retinal vein occlusion, proteins penetrate from leaky vessels into the vitreous. Alternatively, retinal cells produce protein factors and release them into the vitreous.

Methods Vitreous and plasma samples of patients with retinal vein occlusion or macular pucker / macular hole were analyzed by antibody microarrays and ELISA.

Results An antibody based microarray with more than 500 target for screening vitreous samples initially was less enlightening than antibody arrays providing the possibility to quantify up to 30 proteins in an ELISA‐like microassay. Standard curves of antibody microarrays are as linear as those of ELISAs. VEGF values were similar to values measured by ELISA.

Conclusion In our screen, we found some candidate factors which are currently investigated for their potential of influencing retinopathy after retinal vein occlusion. The use of microarrays to identify protein factors involved in retinal disease in the vitreous will be discussed.
Pharmacokinetics of intraocular microplasmin. Revelance to themechanism of action
Authors: DE SMET M
Published: September 2009

Abstract not provided
Target oriented selection of electrophysiological endpoints in preclinical and clinical trials
Authors: ZRENNER E , WILHELM B , PETERS T , KURTENBACH A
Published: September 2009

Purpose The design of pre‐clinical and clinical studies, especially multi‐centre studies shall be discussed concerning the assessment of retinal function, retinal diseases and retinal circuitry as well as biochemistry and the selection of the proper electrophysiological “markers” for appropriate endpoints on the basis of knowledge on possible actions of particular compounds on visual function.

Methods Quality has to be ensured by extended standard operating procedures and case report forms that implement also data that test the quality of procedures and calibrations. This includes harmonized quality standards, quality control, central reading and monitoring as well as data management.

Results On the basis of standards and recommendations of International Society for Clinical Electrophysiology of Vision and EVI.CT.SE, extended protocols have been developed, targeted at rod and cone function, including sensitivity assessment of the retina by V‐log I‐functions, submicrovolt recording for clinical trials in patients with very small responses, ON and the OFF pathway differentiation. Additionally, ERG recovery after a strong bleach is recommended to target alterations in the visual cycle that involves photoreceptors as well as RPE cells.

Conclusion First investigations with such refined standardized protocols have already been performed successfully showing a clear improvement of quality. Normative data are available for the various protocols.