Timing and evolution of periventricular haemorrhage in infants weighing 1250 g or less at birth.

The brains of 50 consecutively admitted infants who weighed 1250 g or less at birth were examined with real time ultrasound. Of 30 (60%) who had periventricular haemorrhage (PVH), 19 (63%) bled on the first day and 17 (57%) showed extension of the initial haemorrhage on serial scans. The median age was 16 hours when PVH was first detected and 48 hours when PVH reached its maximum extent. Ventricular size at birth correlated with gestation. Progressive ventricular growth was seen after birth in infants both with and without PVH. Charts of normal ranges of ventricular size and head circumference were drawn up from birth to 10 weeks of age. All infants with PVH showed a transient increase in ventricular size at 2 weeks of age but most returned to normal by 6 weeks of age. Ventricular dilatation after PVH that was greater than the 95th centile for this population developed in 5 (31%) of 16 survivors, four of whom subsequently developed hydrocephalus, although none required ventriculo peritoneal shunting. The optimal timing for diagnosis with ultrasound is at the end of the first week for PVH and the second to third week for ventricular dilatation.