in partial fulfil]ment of the - MSpace - University of Manitoba

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8.4 RAPID DÀRK ÀDÀPTATION TEST FOR USE WITH CHI LDREN
Although vitamin A deficiency disease is a problem in adults (Sabrell
and Harris, 1967), parLicular victims of the deficiency are children.
The most susceptible age group is from 9 months to 4 years (Sabrell and
Harris, 1967). In a review of xeropathalmia and keratomalacia, (Sommer
et aI., 1981 ) it was reported that over 60,000 Indonesian children
become xerophthalmic every year and by extrapolation of these findings
about 500,000 nelv cases of xerophthalmia, half of which lead to blindness
occur each year in India, Bangladesh, Phillipines and Indonesia
combined. Sommer and NuhiIal (1982) studied the nutritional factors in
the same group of Indonesian children. They observed that the serum
Vitamin À levels were depressed in all subjects, and that the level was
proportional to the severity of corneal changes. Solomons et al. (1982)
have studied the applicability of Thornton's Rapid Dark Àdaptation Test
in children. The study population was 14 males and 13 females (aged
5-12 years) in Guatemala and 1'1 males and 7 females (aged 4-5 years) in
Baltimore, USA. The study in Guatemala City was carried out at the
Institute of Nutrition of CenLraI Àmerica and Panama (lHCep). The study
in Baltimore rvas carried out in a day-school setting. All children had
normal ophthalmoscopic examination and a visual acuity of at least
20/100.
The test administered in both GuatemaLa and Baltimore ¡rere modifications
of Thornton's (1977 ) npet. They were based on the reLinal purkinje
shift and involved the timed, sequential separation of white, blue
and red discs from a black. surface in dim illumination. In Guatemala,
the procedure was identical to that originally described by ThornLon