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Premature infants are at risk of developing metabolic bone disease mainly because of low calcium and phosphorus intake. We have examined the effect of different mineral supplements on bone mineral content at term in 127 premature infants with gestational age <32 wk in a double-blinded randomized trial. We used either phosphate supplementation of human milk as recommended by the European Society of Pediatric Gastroenterology and Nutrition or fortified supplementation with protein, calcium, and phosphorus or preterm formula as recommended by the American Academy of Pediatrics. The intervention period was from 1 week old until 36 wk of gestational age, and the infants were fed approximately 200 mL x kg(-1) x d(-1). Bone mineral content was measured at term by dual-energy x-ray absorptiometry scan. Surprisingly, neither phosphate, fortifier, nor preterm formula supplementation had any significant effect on bone mineral content at term compared with infants fed their own mother's milk only. There was a tendency to higher total bone mineral content in infants fed preterm formula compared with infants fed their own mother's milk only (p = 0.05), but when the bone mineral content was corrected for the size of the infant, there was no difference (p = 0.68). Infants fed preterm formula had a significantly higher weight at term compared with infants fed their own mother's milk only (p = 0.02), but did not differ significantly in length or head circumference. In a regression analysis, the amount of supplemented phosphorus was significantly associated with weight at term (p = 0.008). We conclude that when feeding 200 mL x kg(-1) x d(-1), mineral supplementation of human milk or use of preterm formula does not significantly improve bone mineralization outcome at term.

The purpose of this study was to determine whether visual stimulation in sleeping infants and young children can be examined by functional magnetic resonance imaging. We studied 17 children, aged 3 d to 48 mo, and three healthy adults. Visual stimulation was performed with 8-Hz flickering light through the sleeping childs' closed eyelids. Functional magnetic resonance imaging was performed with a gradient echoplanar sequence in a l.5-T magnetic resonance scanner. Six subjects were excluded because of movement artifacts; the youngest infant showed no response. In 10 children, we could demonstrate areas of signal decrease during visual stimulation in the occipital cortex (mean decrease 2.21%), contrary to the signal increase observed in the adult controls (mean increase 2.82%). This decrease may be due to a higher proportional increase in oxygen extraction compared with increase in cerebral blood flow during activation. The different response patterns in young children and adults can reflect developmental or behavioral differences. Localization of the activation seemed to be age-dependent. In the older children and the adults, it encompassed the whole length of the calcarine sulcus, whereas it was restricted to the anterior and medial part of the calcarine sulcus in the younger infants. This may reflect a different functional organization of the young child's visual cortex or the on-going retinal development.

To investigate the metabolic consequences of germinal matrix hemorrhage (GMH) we used volume-selective 1H magnetic resonance spectroscopy in the striatal region in 12 preterm infants with predominantly small GMH. Both sides of the brain were investigated twice. Metabolite indices were calculated as the metabolite signal, recorded with TR = 1.6 s and TE = 272 ms, divided by the fully relaxed water signal corrected for transverse relaxation time constant (T2) decay. At the first investigation, when the infants were 32.5 +/- 2.0 (mean +/- SD) wk postmenstrual age, the hemorrhage was unilateral or markedly asymmetrical in size in 10 of 12 infants. The lactate index was higher (p < 0.01) and the phosphocreatine + creatine (Cr) (p < 0.05) and N-acetyl-L-aspartate (NAA) (p < 0.05) indices lower in the side with the larger hemorrhage. At the second investigation, 54.1 +/- 2.7 wk postmenstrual age, no sign of a previous GMH could be seen on magnetic resonance imaging in three of 10 infants. Lactate could be detected in two of 10 infants only, and the Cr and NAA indices did not differ between sides. However, the choline index was significantly higher in the side with the larger hemorrhage (p < 0.01). We conclude that GMH is initially followed by lactate accumulation and possibly a delay in maturation as indicated by the transiently low Cr and NAA indices. Moreover, an increased choline index at the corrected age of 3 mo indicates a more persistent metabolic change after small GMH.