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Ingeborg Stalmans,1 Hans Lemij,2 Jonathan Clarke,3 Christophe Baudouin4 On behalf of the GOAL study group1Department of Ophthalmology, UZ Leuven, Leuven, Belgium; 2Glaucoma Service, Rotterdam Eye Hospital, Rotterdam, the Netherlands; 3NIHR Biomedical Research Centre - Moorfields Eye Hospital, NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK; 4Ophthalmology Unit, Quinze-Vingts National Hospital and Vision Institute, IHU ForeSight, Sorbonne University, Paris, FranceCorrespondence: Christophe BaudouinOphthalmology Unit, Quinze-Vingts National Hospital and Vision Institute, IHU ForeSight, Sorbonne University, Paris, FranceEmail cbaudouin@15-20.frAbstract: Ocular Surface Disease (OSD) and hyperemia are the most common adverse events of topical ocular medications. While active compounds may cause allergic reactions or irritation, preservatives, which are intended to prevent bacterial growth, are toxic as well. Therefore, the most recent glaucoma medications no longer contain preservatives. Despite this, local tolerability may still impact treatment compliance and patient quality of life. We conducted an observational, multi-center, international, cross-sectional study in 793 treated and stabilized glaucoma patients to assess patient satisfaction and local tolerability of their treatment. The vast majority (93.7%) of patients was satisfied or very satisfied with their treatment in terms of tolerability and only 6.3% were dissatisfied. However, ophthalmological examination showed a high frequency of ocular signs: conjunctival hyperemia (32%), OSD (42.5%) and positive conjunctival fluorescein staining (10.3%). Additionally, patients reported symptoms upon instillation (31.4%) and between instillations (57.3%); 25.1% of patients were using tear substitutes. All signs and symptoms were significantly (p< 0.001) associated with patient dissatisfaction. A logistic regression model indicated that dissatisfaction was higher in patients with symptoms upon instillation and in those using tear substitutes (OR: 3.03 and 4.63, respectively). The mean patient tolerability score to treatment was 82.7± 16.1 on a 100-point visual analogue scale. In conclusion, even if patients may be highly satisfied with their current treatment, most of them present ocular signs and symptoms. A treatment change should be considered in case of clinical signs or patient-reported symptoms.Keywords: glaucoma, tolerance, preservatives, tear substitutes, patient satisfaction, ocular surface disease

Background: Eye Movement Perimetry (EMP) uses Saccadic Eye Movement (SEM) responses for visual field evaluation. Previous studies have demonstrated significant delay in initiation of SEMs among glaucoma patients in comparison with healthy subjects. The aim of the current study was to develop an EMP-based screening grid to identify glaucomatous visual field defects.Methods: An interactive test consisting of 36 locations and two stimulus contrasts (162 cd/m2 and 190 cd/m2 on a background of 140 cd/m2) was evaluated in 54 healthy subjects and 50 primary glaucoma patients. Each subject was presented a central fixation target combined with the random projection of Goldmann size III peripheral targets. Instructions were given to look at each peripheral target on detection and then re-fixate at the central fixation target while the saccades were assessed using an eye tracker. From each seen peripheral target, the Saccadic Reaction Time (SRT) was calculated for contrast level 162 cd/ m2. These values were used to plot Receiver Operating Characteristic (ROC) curves for each test locations and the Area Under the Curve (AUC) values were used to identify the locations with highest susceptibility to glaucomatous damage. Each stimulus location with an AUC less than 0.75 along with its mirrored test location around the horizontal axis were eliminated from the grid.Results: The mean age was 48.1 ± 16.6 years and 50.0 ± 14.5 years for healthy subjects and glaucoma patients respectively. A significant increase of SRT values by 76.5% (p < 0.001) was found in glaucoma patients in comparison with the healthy subjects. From the ROC analysis, ten out of 36 locations meeting the cut-off criteria of AUC were eliminated resulting in a new grid containing 26 test locations. SRT values were significantly different (p < 0.05) between the healthy subjects and glaucoma irrespective of the grids used.Conclusions: The present study resulted in a screening grid consisting of 26 locations predominantly testing nasal, superior and inferior areas of the visual field. An internal validation of the modified grid showed 90.4% of screening accuracy which makes it a potential approach for population based glaucoma screening. [ABSTRACT FROM AUTHOR]

Objectives: One method for assessing pathological retinal nerve fiber layer (NFL) appearance is by comparing the NFL to normative values, derived from healthy subjects. These normative values will be more specific when normal physiological differences are taken into account. One common variation is a split bundle. This paper describes a method to automatically detect these split bundles.Methods: The thickness profile along the NFL bundle is described by a non-split and a split bundle model. Based on these two fits, statistics are derived and used as features for two non-parametric classifiers (Parzen density based and k nearest neighbor). Features were selected by forward feature selection. Three hundred and nine superior and 324 inferior bundles were used to train and test this method.Results: The prevalence of split superior bundles was 68% and the split inferior bundles' prevalence was 13%. The resulting estimated error of the Parzen density- based classifier was 12.5% for the superior bundle and 10.2% for the inferior bundle. The k nearest neighbor classifier errors were 11.7% and 9.2%.Conclusions: The classification error of automated detection of split inferior bundles is not much smaller than its prevalence, thereby limiting the usefulness of separate cut-off values for split and non-split inferior bundles. For superior bundles, however, the classification error was low compared to the prevalence. Application of specific cut-off values, selected by the proposed classification system, may therefore increase the specificity and sensitivity of pathological NFL detection. [ABSTRACT FROM AUTHOR]

PurposeFirst, to determine the absolute measurement precision of scanning laser ophthalmoscopy (SLO) parameters, by expressing them as 95% limits of agreement (LA95%). Second, to propose a method for mathematically estimating the clinical ability of a parameter to monitor disease progression, expressed as the Discriminating Capacity Index (DCI).MethodsWe measured the optic disc of 14 healthy volunteers and 14 glaucoma patients. LA95%-values were calculated from the average standard deviation of three measurements on the same day for repeatability, and three measurements on separate days within a 6-week period for reproducibility. We then calculated the DCI by dividing the measurement range by its LA95% in healthy subjects and glaucoma patients separately. Thus, the DCI takes into account both the dynamic range of disease progression and the extent of measurement variance, providing an index of the possible clinical usefulness of a parameter. As the DCI is dimensionless it allows comparison across various parameters and across technologies.ResultsIn the glaucoma group, the SLO parameters with the highest DCIs were ‘volume below’ (DCI, 9.38) and ‘mean contour depth’ (DCI, 8.02). In the healthy group, ‘Neuroretinal rim area’ had the highest index (DCI, 2.15).ConclusionSLO optic disc biometry is uniformly reproducible and may prove a clinically useful method for glaucoma follow-up, due to the high DCI found for several parameters. The capacity to detect conversion from health to glaucoma is less pronounced, possibly due to a larger biological variability found in healthy volunteers.Eye (2006) 20, 755–763. doi:10.1038/sj.eye.6701993; published online 1 July 2005 [ABSTRACT FROM AUTHOR]

PurposeAutomated glaucoma detection in images obtained by scanning laser polarimetry is currently insensitive to local abnormalities, impairing its performance. The purpose of this investigation was to test and validate a recently proposed algorithm for detecting wedge-shaped defects.MethodsIn all, 31 eyes of healthy subjects and 37 eyes of glaucoma patients were imaged with a GDx. Each image was classified by two experts in one of four classes, depending on how clear any wedge could be identified. The detection algorithm itself aimed at detecting and combining the edges of the wedge. The performance of both the experts and the algorithm were evaluated.ResultsThe interobserver correlation, expressed as ICC(3,1), was 0.77. For the clearest cases, the algorithm yielded a sensitivity of 80% at a specificity of 93%, with an area under the ROC of 0.95. Including less obvious cases by the experts resulted in a sensitivity of 55% at a specificity of 95%, with an area under the ROC of 0.89.ConclusionsIt is possible to automatically detect many wedge-shaped defects at a fairly low rate of false-positives. Any detected wedge defect is presented in a user-friendly way, which may assist the clinician in making a diagnosis.Eye (2006) 20, 776–784. doi:10.1038/sj.eye.6701999; published online 1 July 2005 [ABSTRACT FROM AUTHOR]