Congdon N, Sommer A, Severns M, Humphrey J, Friedman D, Clement L, Wu L S, Natadisastra G
Dana Center for Preventive Ophthalmology, Baltimore, MD, USA.
Am J Clin Nutr. 1995 May;61(5):1076-82. doi: 10.1093/ajcn/61.4.1076.
A prototype scotopic sensitivity machine was used to evaluate pupillary and visual thresholds for 295 Indonesian children aged 1-5 y, most of whom were initially vitamin A-deficient. Subjects were tested 6 and 9 mo after receiving a high dose of vitamin A. A group of 136 older children was tested at 6 mo after dosing; all subjects underwent testing at 9 mo. After testing at 9 mo, children randomly received either a second high dose of vitamin A or placebo and were tested a final time 2 wk later. Children with abnormal pupillary thresholds had significantly higher relative dose responses (RDRs) (P < 0.01) and significantly lower serum retinol values (P = 0.05) than did normal children. The mean pupillary threshold rose (eg, retinal sensitivity fell) as vitamin A status deteriorated between 6 and 9 mo after initial dosing, and was significantly different from a group of normal American children tested previously (P < 0.001). After placebo-controlled dosing, the decline in pupillary and visual thresholds (rise in retinal sensitivity) was significant for children receiving vitamin A but not for children receiving placebo.
使用一台原型暗适应敏感度机器对295名1至5岁的印度尼西亚儿童进行瞳孔和视觉阈值评估，这些儿童大多数最初缺乏维生素A。在接受高剂量维生素A后6个月和9个月对受试者进行测试。一组136名年龄较大的儿童在给药后6个月进行测试；所有受试者在9个月时接受测试。在9个月测试后，儿童随机接受第二次高剂量维生素A或安慰剂，并在2周后进行最后一次测试。瞳孔阈值异常的儿童相对剂量反应（RDR）显著更高（P < 0.01），血清视黄醇值显著更低（P = 0.05），与正常儿童相比。在首次给药后6至9个月期间，随着维生素A状态恶化，平均瞳孔阈值升高（即视网膜敏感度下降），并且与之前测试的一组正常美国儿童有显著差异（P < 0.001）。在安慰剂对照给药后，接受维生素A的儿童瞳孔和视觉阈值下降（视网膜敏感度升高）显著，而接受安慰剂的儿童则不然。
