Age norms for grating acuity and contrast sensitivity measured by Lea tests in the first three years of life.

AIM

To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test.

METHODS

Lea grating test was used to estimate binocular grating acuity and Hiding Heidi low contrast face test was used to estimate contrast sensitivity in 600 healthy infants and children. Age ranged from 3 to 36mo subdivided into 12 groups subjected for full ophthalmologic and pediatric examinations.

RESULTS

The grating acuity developed along the first three years of life. It ranged from 1.88±0.32 c/d at 3mo to 30.95±0.77 c/d at 36mo. The most rapid development was during the first 12mo and the slowest development was from 30 to 36mo. The contrast sensitivity showed rapid development in the first two years of life. Its mean value ranged from 4.23±1.17 at 3mo to 78.26±8.21 at 24mo. It was constant at the highest score (80) thereafter.

CONCLUSION

Age norms for grating acuity along with contrast sensitivity offer a more comprehensive measure of spatial vision and should be incorporated in clinical practice for better visual assessment in preverbal and nonverbal children.