Possible etiological factors in extensive periventricular leukomalacia of preterm infants.

During a twelve-month period five cases of extensive periventricular leukomalacia (PVL) in preterm infants with a gestational age of 31-32 weeks were diagnosed by routine ultrasound screening of preterm infants. The perinatal courses and later development of these infants were compared with 12 other infants with a comparable gestational age born during the same time period. PVL babies were delivered more often by the vaginal route (p = 0.0034), and their mean highest serum total bilirubin value was significantly higher (p = 0.0054) than that of the control infants. The mean value of the highest blood pH during the first 72 hours of life was also significantly higher (p = 0.0311) in PVL babies than in control babies. On the basis of these results we speculate that in addition to ischaemia in the periventricular area, bilirubin toxicity may play an additional role in the severe damage seen in extensive periventricular leukomalacia.