ABSTRACT
PURPOSE: To compare visual acuity with two visual acuity charts in preschool children. MATERIALS AND METHODS: Visual acuity measurement with Lea symbols and Bailey-Lovie tumbling E chart was performed on children between 3 and 6 years of age. Visual acuity data from the two charts were analyzed with Bland-Altman plot to determine the limits of agreement. The Wilcoxon signed test was performed in children aged 3-4 years and in children aged 5-6 years separately to evaluate the influence of age. The inter-eye difference between the two charts were further analyzed with the paired t-test. A p value > 0.05 was considered statistically significant. RESULTS: A total of 47 children were enrolled for the study. The average logarithm of the Minimum Angle of Resolution (LogMAR) monocular visual acuity with Lea symbols (0.17 ± 0.13) was better than the Bailey-Lovie tumbling E chart (0.22 ± 0.14). The mean difference between Bailey-Lovie tumbling E chart and Lea symbol chart was 0.05 ± 0.12 in logMAR units. A second analysis eliminating outliers showed the same result but lower differences (n = 43, 0.05 ± 0.05 logMAR units). Visual acuity results between the two charts in children aged 3-4 years showed a significant difference (p = 0.000), but not for children aged 5-6 years (p = 0.059). Inter-eye differences between the two charts was not statistically significant (p = 0.77). CONCLUSION: Bailey-Lovie tumbling E chart is comparable to the Lea symbols chart in pre-school children. But preference should be given to Lea symbols for children aged 3-4 years as the symbols are more familiar than a directional test for this age group.
Subject(s)
Vision Screening/instrumentation , Visual Acuity/physiology , Child , Child, Preschool , Female , Humans , Male , Vision, Binocular/physiologyABSTRACT
This six-year retrospective longitudinal study was conducted to examine the changes in the pattern of prescribing soft contact lenses in an optometry centre located in a University in South India. Details regarding the type of lenses, lens material, wearing pattern and the clinical diagnoses were analyzed from January 2006 to December 2011. A total of 1273 soft contact lens fits (n=1273) were analyzed. Two-third of the total lenses dispensed was for females and their mean age (24.0±8.3 yrs) was less than that of male (27.0±11.2 yrs) lens users. Nearly 70% of them had myopia and 48% wore conventional soft contact lenses. During the studied six years, the percentage of conventional lenses declined by 60%. This study demonstrated a gradual and significant increase in popularity of disposable contact lenses and silicone hydrogel lens material which is comparable to the global trend.
Subject(s)
Contact Lenses, Hydrophilic/statistics & numerical data , Contact Lenses, Hydrophilic/trends , Practice Patterns, Physicians'/statistics & numerical data , Practice Patterns, Physicians'/trends , Prescriptions/statistics & numerical data , Vision Disorders/epidemiology , Vision Disorders/rehabilitation , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Educational Status , Female , Health Care Surveys , Humans , India/epidemiology , Infant , Longitudinal Studies , Male , Middle Aged , Physicians/statistics & numerical data , Physicians/trends , Prevalence , Professional Competence/statistics & numerical data , Young AdultABSTRACT
BACKGROUND: Many clinical techniques exist to quantify the magnitude of heterophoria in free space. In this article, we determine the agreement between the modified Thorington test and three different tests for dissociated heterophoria at near distance in free space. METHODS: The modified Thorington, Maddox rod, von Graefe and alternate cover tests were performed on 49 university students at near distance in free space. The 95% limits of agreement between the modified Thorington and other tests were compared in pairs by using the Bland-Altman statistical test. RESULTS: While the Maddox rod-modified Thorington pair showed narrow 95% limit range (2.5 to -3.34(Δ) ) between each other compared to the von Graefe-modified Thorington (4.2 to -3.15(Δ) ) and alternate cover test-modified Thorington pairs (4.52 to -2.77(Δ) ), none of the three tests showed good agreement with the modified Thorington test. CONCLUSION: The modified Thorington test cannot be interchanged with the other three near tests for heterophoria in free space. The accuracy in the measurement and the different methods of dissociation may play a crucial role in comparisons of the different tests for heterophoria.
Subject(s)
Accommodation, Ocular/physiology , Oculomotor Muscles/physiology , Optometry/methods , Adolescent , Adult , Female , Humans , Male , Reference Values , Strabismus/diagnosis , Strabismus/physiopathology , Vision Tests , Young AdultABSTRACT
AIM: To determine the efficacy of a remotely operated computer-based logarithmic (logMAR) visual acuity chart. METHODS: Visual acuity was tested using a laptop or computer-based logMAR chart (COMPlog) for all subjects by two different methods. The methods differed by the physical presence and absence (remote) of an optometrist and in the mode of instructions provided. Remote access was obtained through the internet, using Teamviewer software to control the system linked to COMPlog and instructions were provided by telephone. The order of measurements and the eye to be tested was randomised. logMAR visual acuity and time taken were recorded. A questionnaire was used to assess the participant's feedback. RESULTS: Intraclass correlation for visual acuity between the two methods (α=0.964, 95% CI 0.937 to 0.979). There was no statistically significant difference (p=0.648) in the median visual acuity measurement between the two methods (median difference 0.00, IQR 0.20 logMAR). The time taken between the two methods was not statistically significant (p=0.457). There was no significant difference in the responses to the questionnaire between the study methods (p=0.119). CONCLUSIONS: Tele (remotely controlled) visual acuity measurement is as reliable as that measured with the physical presence of an optometrist.