[A study of cerebral blood flow in preterm newborns. The physiologic modification of diastole].

An evaluation of cerebral blood flow (CBF) was carried out with a Toshiba Sonolayers-S SSH-60 A echography in 127 infants with open major fontanelle which were divided in 3 groups: a) 69 non premature newborn, in which a physiological variation of all CBF parameters was found; b) 29 neurologically normal preterm infants, where the resistance index always was higher than in the preceding group, at the expense of a lower diastolic flow, in which for the first time the "physiological variation of diastole" independent of the gestational age is reported. This variation results in changes in the cerebral flow in the situations of exercise, rest or stress; c) 29 preterm infants with some abnormality, who also showed the physiologic variation of diastole with a poor flow quality were found.