“VisualFields Easy”: an iPad application as a simple tool for detecting visual field defects

@#<p style="text-align: justify;"><strong>PURPOSE/OBJECTIVE:</strong> This study aims to determine the reliability of the "VisualFields Easy" application in detecting visual field loss among ophthalmology patients; and to determine the sensitivity, specificity, positive predictive and negative predictive values of this examination using the Humphrey Visual Field Analyzer as the gold standard.</p> <p style="text-align: justify;"><strong>METHODS:</strong> This is an analytical study that enrolled subjects requiring visual field examination as part of the comprehensive evaluation of their ophthalmologic condition. Each subject was tested using the standard automated Humphrey Field Analyzer (Carl Zeiss Meditec, Inc., Germany) with the 30-2 Swedish Interactive Thresholding Algorithm (SITA) and the "VisualFields Easy" application (background = 10 cd / m2 ; size V target; 16-dB stimulus) loaded in an iPad 2 ver. 8.3. The print outs of each test were then interpreted independently by the principal investigator and verified by a glaucoma specialist as positive or negative for visual field defects and computation for sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were done.</p> <p style="text-align: justify;"><strong>RESULTS:</strong> The study included 137 eyes of 77 patients, 52 (68%) females and 25 (32%) males, age ranging from 18 to 82 years with a mean (SD) of 58 (+ 14) years. The mean test duration for the standard Humphrey perimetry was 7 minutes 50 seconds (SD + 0.08s), and 3 minutes 21 seconds (SD + 0.01s) for the "VisualFields Easy". Correlations of False Positives and False Negatives between the 2 tests were p=0.02 and p=0.03 respectively and that there was no statistically significant difference between the reliability parameters of the two tests. There were a total of 74 positives and 63 negatives visual field defects for the Humphrey. These were considered as the True Positive (TP) and True Negative (TN) values. For the "VisualFields Easy", there were 67 positives and 70 negatives. The results of the "VisualFields Easy" were plotted against the Humphrey perimetry. Sensitivity was computed at 91% and specificity at 100%. Likewise the Positive Predictive Value (PPV) was computed to be 100% and the Negative Predictive Value (NPV) was computed at 90%.</p> <p style="text-align: justify;"><strong>CONCLUSION:</strong> The "VisualFields Easy" application is a quick, easily accessible and fairly reliable way of measuring visual field abnormalities, both for glaucoma and neuro-ophthalmology patients. The application is not intended to replace standard automated perimetry machines, but it may have a role in detecting, documenting and monitoring visual field defects in low resource settings where visual field tests are not available.</p>

Efficacy of vitamin supplementation in preventing color vision abnormalities among patients undergoing DOTS for Tuberculosis

Objective@#To determine if vitamin supplementation can prevent the development of color vision abnormalities in patients taking ethambutol as part of DOTS for tuberculosis (TB).@*Methods@#A randomized, placebo-controlled, single-blind clinical trial was conducted among newly diagnosed category-1 TB patients enrolled in DOTS health centers in the third district of Manila from June 2011 to August 2012. Before starting therapy, the participants underwent a complete eye evaluation including baseline color vision tests using the Ishihara Color Vision Plates (Ishihara), Farnsworth Panel D-15 (FD 15), and Lanthony Desaturated D-15. Only subjects who passed the three color vision tests were included in the study. They were divided into 2 groups: Group A received vitamin supplementation and Group B received a placebo. Follow-up color vision testing was done monthly for 3 months.@*Results@#There were 105 patients included in the study, 77 males and 28 females, age ranging from 16 to 68 years with a mean of 37 years. Forty three (43) patients received vitamin supplementation (group A) and 62 received placebo (group B). After one month of DOTS, 5 of 43 patients (11. 6%) in group A and 10 of 62 patients (16.1%) in group B developed color vision abnormalities, detected only with the Lanthony Desaturated test. The absolute risk reduction (ARR) of color vision abnormalities by vitamin supplementation was 4.5%, with the number needed to treat (NNT) of 23. After the second month of therapy, ARR was 7.4% and NNT was 14. ARR was highest in the third month at 8.3%, with a corresponding decreased NNT of 12. Among patients who developed color vision abnormalities, reversal of the abnormalities was observed in 80% of 5 subjects in group A, and 40% of 10 patients in group B. By the third month of treatment, all in group A already had normal color vision, while 40% in group B still showed abnormal color vision. @*Conclusion@#This study showed that vitamin supplementation was effective in reducing the risk of, and in reversing cases of, color vision abnormalities among patients undergoing DOTS therapy for tuberculosis.

Prevalence of graves ophthalmopathy among patients with thyroid disease

Objective@#This study determined the prevalence of Graves ophthalmopathy among thyroid-disease patients at a tertiary government hospital.@*Methods@#Patients with thyroid disease seen at a tertiary hospital from February to September 2007 were enrolled. All patients underwent ophthalmologic examination consisting of visual-acuity testing; exophthalmometry; examination for presence of lid retraction, lid lag, and lateral flare; globe position; external-ocular-muscle-movement grading; corneal light reflex; and direct funduscopic examination. All clinical findings were recorded and data were analyzed. Chi square and Fisher’s exact tests determined the association of gender and age to the different ocular signs and symptoms. One-way analysis of variance (ANOVA) compared the average number of ocular symptoms among the different age groups.@*Results@#A total of 121 patients, 20 males and 101 females, with thyroid disease were evaluated. 47.93% had Graves ophthalmopathy, occurring more frequently among patients aged between 30 and 49 years. The most common signs were eyelid retraction, proptosis, and lid lag.@*Conclusion@#Graves ophthalmopathy occurs frequently among patients with thyroid disease, especially those more than 30 years of age.