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This study described the development of a haploscope-based pupillometer for the parametrization of the Pupillary Light Reflex (PLR), and its feasibility in a set of 30 healthy subjects (light or dark-colored irides) and five patients diagnosed with Relative Afferent Pupillary Defect (RAPD). Our supplementary aim focused on evaluating the influence of iris colour on the PLR to decide whether a difference in PLR parameters should be anticipated when this system is used across ethnicities. All the participants underwent a customized pupillometry protocol and the generated pupil traces, captured by an eye tracker, were analyzed using exponential fits to derive PLR parameters. A Pupil Response Symmetry (PRS) coefficient was calculated to predict the presence of RAPD. The mean (SD) Initial PD during dilation (3.2 (0.5) mm) and the minimum PD during constriction (2.9 (0.4) mm) in the light iris group had a statistically significant (p < 0.001) higher magnitude compared to the dark iris group. The normal limits of the PRS coefficient ranged from − 0.20 to + 1.07 and all RAPD patients were outside the calculated normal limits. This proposed system, analysis strategies, and the tested metrics showed good short-term repeatability and the potential in detecting pupil abnormalities in neuro-ophthalmic diseases. [ABSTRACT FROM AUTHOR]

In eye movement perimetry (EMP), the saccadic reaction time (SRT) to 'seen' visual stimuli are delayed in glaucoma. Evaluating SRT behaviour in hemi-field sectors could refine its clinical implication. The development phase included 60 controls retrospectively and for the test cohort in evaluation phase, another 30 healthy subjects and 30 glaucoma patients were recruited prospectively. The SRTs were used to calculate the normative limits within 5 predefined hemi-field sectors. Scores were assigned to probabilities for SRT at the level of 5%, 2.5% 1% and 0.5%. Per sector pair, a probability score limit (PSL) was calculated at each of the four levels and were compared with the scores obtained from the test cohort. The classification accuracy 'normal versus abnormal' was assessed for PSL in EMP and compared with glaucoma hemi-field test in standard automated perimetry. We found no statistically significant differences in SRTs between the mirror sectors in healthy subjects. The PSL at 2.5% had moderate classification accuracy with a specificity of 77% and sensitivity 70%. This could be suggestive of an SRT delay in the overall visual field in glaucoma. [ABSTRACT FROM AUTHOR]

We report a case of six-year-old boy who presented with a progressive intracorneal cyst in the left eye. Anterior segment optical coherence tomography (AS-OCT) was performed, and it showed the location of the cyst in the corneal stroma. Its dimension was measured to be 7.09 × 2.12 mm. The cyst aspiration was successfully done. AS-OCT helped in the management and follow-up of the condition. [ABSTRACT FROM AUTHOR]

Purpose: The evaluation of visual impairment requires the measurement of visual acuity with a validated and standard logMAR visual acuity chart. We aimed to construct and validate new logMAR visual acuity chart in Indian languages (Hindi, Bengali, Telugu, Urdu, Kannada, Malayalam, and Assamese).Methods: The commonly used font in each language was chosen as the reference and designed to fit the 5 × 5 grid (Adobe Photoshop). Ten letters (easiest to difficult) around median legibility score calculated for each language based on the results of legibility experiment and differing by 10% were selected. The chart was constructed based on the standard recommendations. The repeatability of charts was tested and also compared with a standard English Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart for validation.Results: A total of 14 rows (1.0 to -0.3 logMAR) with five letters in each line were designed with the range of row legibility between 4.7 and 5.3 for all the language charts. Each chart showed good repeatability, and a maximum difference of four letters was noted. The median difference in visual acuity was 0.16 logMAR for Urdu and Assamese chart compared to ETDRS English chart. Hindi and Malayalam chart had a median difference of 0.12 logMAR. When compared to the English chart a median difference of 0.14 logMAR was noted in Telugu, Kannada, and Bengali chart.Conclusion: The newly developed Indian language visual acuity charts are designed based on the standard recommendations and will help to assess visual impairment in people of these languages across the country. [ABSTRACT FROM AUTHOR]

Context: Various systems are available to stage glaucomatous field defects into different severity grades. Still, the preference for such systems among Indian eye care practitioners (ECPs) and the consensus between them are not explored. Purpose: To compare the clinical performance of perimetric glaucoma staging systems and to assess their preference patterns among Indian ECPs. Setting and Design: Retro-prospective cross-sectional study. Methods: Three investigators stratified 400 perimetry reports using four systems: Hodapp Anderson Parrish (HAP), enhanced Glaucoma Severity Staging (eGSS), Advanced Glaucoma Intervention Study (AGIS), and Collaborative Initial Glaucoma Treatment Study (CIGTS). Their performance was compared in terms of agreement and association. Following this, 30 ECPs from across the country segregated a subset of reports (n = 20) into different stages based on their system of choice, and their preferences/perceptions about the available perimetry staging systems were enquired and documented. Statistical Analysis Used: Descriptive statistics, Kruskal–Wallis, Cohen's kappa, and Spearman's correlation. Results: For the consolidated severity stages, substantial agreements (K ranging from 0.61 to 0.75) were found between all the systems, except for HAP–CIGTS (K = 0.58) and AGIS–CIGTS (K = 0.51). All ECPs were aware of perimetry staging systems, and a high preference was reported for HAP (97%) due to ease of implementation and interpretation. Conclusion: Among the four staging systems, the highest agreement was found between HAP and eGSS. A majority of ECPs proposed the need for a uniform classification system across the practices for clinical comparisons and patient education. [ABSTRACT FROM AUTHOR]

Aim: To compare the saccadic reaction time (SRT) in both the central and peripheral visual fi eld in normal and glaucomatous eyes using eye movement perimetery (EMP). Materials and Methods: Fift y-four normal and 25 glaucoma subjects underwent EMP and visual fi eld testing on the Humphrey Field Analyser (HFA) 24-2 program. The EMP is based on infrared tracking of the corneal reflex. Fift y-four test locations corresponding to the locations on the 24-2 HFA program were tested. SRTs at diff erent eccentricities and for different severities of glaucoma were compared between normal and glaucoma subjects. Results: Mean SRT was calculated for both normal and glaucoma subjects. Mann-Whitney U test showed statistically significant (P < 0.001) diff erences in SRT's between normal and glaucoma subjects in all zones. Conclusion: SRT was prolonged in eyes with glaucoma across diff erent eccentricities. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the screening accuracy of an Eye Movement Perimetry (EMP) in comparison with Frequency Doubling Perimetry (FDP) and to investigate the patient preference and perception towards these visual field screening methods. Methods: A total of 104 healthy subjects (mean age (SD) of 48 (14) years) and 73 glaucoma patients (mean age (SD) of 52 (13) years) were recruited. All the participants underwent a comprehensive ophthalmic evaluation including the 24-2 SITA standard protocol on the Humphrey Field Analyzer (HFA). This was followed by the 26-point protocol in EMP and the C-20-1 protocol in FDP. During EMP, all subjects were instructed to fixate a central target and to look at the detected peripheral target, followed by refixation of the central target and Saccadic Reaction Time (SRT) towards each of the "seen" stimuli was calculated. Next, a questionnaire was administered to evaluate the patient preference and perception towards the perimetry techniques. Mean SRTs and Robin scores were used to plot Receiver Operating Characteristics (ROC) curves to determine the screening accuracies. From the questionnaire survey, the frequency distributions of the responses were calculated. Results: Robin score and SRT were significantly increased in glaucoma patients in comparison with the age-matched healthy subjects (p < 0.001). The ROC analysis revealed comparable Area Under the Curve (AUC) values (0.95, p = 0.81) with a specificity of 95.2% for FDP and 96.2% for EMP with a sensitivity of 87.7%. Thirty-seven percent of the older age group (≥ 40 years) and 65% of severe glaucoma patients showed preference for EMP over FDP. Conclusions: This study results indicate that the customized protocol in EMP provides efficient and rapid means of screening visual field defects in glaucoma, which compared well with FDP. Elderly healthy participants and patients with moderate and severe glaucomatous defects preferred EMP as it permitted natural reflexive eye movements thereby resembling a real-life test setting. [ABSTRACT FROM AUTHOR]