Comparison of lea gratings with cardiff acuity cards for vision testing of preverbal children

Abstract

Aims:

To create a normative data for lea grating (LG) in the Indian population and to compare LG with Cardiff Acuity Card (CAC).

Settings and Design:

Normative Data was acquired from normal children between 6 months-3 years coming to the ‘Immunisation Clinic’ and ‘Well-Baby Clinic’ at a Civil Hospital. To compare LG with CAC, normal and amblyopic children between 6 months-3 years were evaluated,

Materials and Methods:

Monocular and binocular visual acuity (VA) was measured using LG and then CAC. VA and time taken to perform the test were compared.

Statistical Analysis Used:

Pearson's Correlation Coefficient to compare VA and Student paired t-test (significance P<0.005) to compare time.

Results:

Two standard deviations of VA of 100 normal children overlapped with that published by Lea. Of the 30 amblyopic children aged 18.32 ± 10.5 months (2-36), 18 were females. VA was 0.95 ± 0.3 logMAR (0.7–1.2) and 1.0 ± 0.6 logMAR (0.5–2.1) binocularly and 1.32 ± 0.08 logMAR (0.2-0.6) and 1.15 ± 0.15 logMAR (0.88-1.48) monocularly on CAC and LG respectively. Pearson's correlation coefficient was 0.98 and 0.63 for binocular and monocular assessment respectively. Time taken to perform LG monocularly and binocularly was significantly less ( P<0.001) than CAC.

Conclusion:

Normative data acquired in Indian pre-verbal children is similar to that published by Lea. Though VA by CAC is better than LG, the two tests are comparable.