[Reference values in vision development of infants with clinical use of the Teller Acuity Cards].

BACKGROUND

Using Teller Acuity Cards (TAC) for clinical visual testing, the question arose how our measurements fitted in the different standard tables of the producer's hand-book. In addition, we wanted to investigate how reliable the measurements of newborn and infants were and what the examination success rate under clinical conditions was.

METHODS

At the paediatric clinic of the University of Erlangen, we tested the binocular grating acuity of 98 infants up to the age of one year, using the complete set of Teller acuity cards. In addition, 41 of the children underwent a monocular vision test.

RESULTS

1. Theoretical: At first we calculated conversion data for our card set. Using this conversion scale from cy/cm in cy/deg and the corresponding vision equivalent we produced our own standards for the development of grating acuity up to the age of one year. 2. Clinical: In 3-5 min per clinical examination we could determine for 90.8% of the patients a vision equivalent. The reliability of the results was age dependent and was at its best at the age of 5-11 months. The reliability was also very dependent on the duration of the test and the number of test runs. This resulted in a limited card choice for each age group.