Vitamin A Blood Serum Levels and Electroretinogram in 5- to 14-Year Age Group in Indonesia and Thailand

Abstract
Using the electroretinogram (ERG) as a response criterion, a group of 33 children aged 5–9 and 21 aged 10–14 were studied to relate the ERG parameters to the vitamin A blood serum levels. Qualitatively, the wave form appears to be independent of the blood serum level. The amplitudes of both the a- and b-waves show a significant positive correlation to the blood serum vitamin A values in the 5–9 age group. No such relationship is found in the older group, although there is no difference in mean vitamin A level. Those children with a past history of clinical manifestations of vitamin A deficiency tend to give lower responses than those without this past history, suggestive of a long-lasting effect of low-deficient vitamin A levels.