Value of sequential MRI in preterm infants.

Since the introduction of neonatal intensive care in the 1970s, there has been a pronounced decrease in overall mortality of premature infants as well as a decrease in the incidence of severe white matter injury, best known as cystic periventricular leukomalacia (c-PVL).(1) While cranial ultrasonography readily visualizes large lesions in the white matter (periventricular hemorrhagic infarction and c-PVL), this technique is not sufficiently sensitive to recognize the much more common and less severe noncystic white matter lesions.(2) The absolute number of extremely preterm infants is increasing because of improved survival rates.(e1.)