Background: Periventricular leukomalacia (PVL) is the most important factor in cerebral palsy in preterm infants.
Methods: In the present study, we investigated 747 preterm infants of less than 36 weeks gestation who were repeatedly examined by cranial ultrasonography and computed tomography (CT) scanning at around 40 weeks of corrected post-menstrual age. The clinical course of these infants was followed for more than 3 years and they were examined by magnetic resonance imaging (MRI) between 12 and 18 months of age.
Results: Single examinations in early infancy were not sufficient to diagnose PVL, but the combination of ultrasonography, CT and MRI examinations allowed the clinical diagnosis of PVL. In preterm infants, clinical PVL could be predicted from cystic PVL and periventricular echogenicity (PVE) 3 or PVE 2 prolonged over 3 weeks on ultrasonography and confirmed by MRI after 11 months of corrected age.
Conclusions: We tried to determine diagnostic criteria for PVL by neuroimaging. Such criteria from neuroimaging for PVL may be useful for determining the exact occurence rate of and clinical risk factors for PVL.