LAUSR

tion between blocks and mydriatic administration was not significant. Adequate pupillary dilatation was always achieved. Three infants showed a self-resolving apnoea episode after drops administration. Mydriatics are routinely used to screen preterm infants for ROP. Several combinations and doses have been used. Although generally safe, mydriatics can occasionally cause systemic side effects in preterm infants (Bolt et al. 1992; Khoo et al. 2000). Although cerebral oxygenation and blood flow are regulated by sympathetic and cholinergic mechanisms, we found no detectable changes associated with administration of phenylephrine 2.5% and tropicamide 0.5%. Main study limitations were the small sample size and the relatively short monitoring time. We conclude that the current protocol for ROP screening was not associated with measurable side effects on preterm cerebral haemodynamics, as assessed by NIRS.