Cystic periventricular leukomalacia: sonographic and CT findings.

Periventricular leukoencephalopathy (PVL) is a pathologic process that has attracted little attention in neurodiagnosis. It is the second most common acquired central nervous system abnormality in neonates, outranked only by germinal matrix hemorrhage. Autopsy series suggest a 7%-22% incidence, but clinical recognition is poor. The diagnosis usually signals a less favorable neurodevelopmental outcome. Twenty-one cases with PVL and later cavitation (cystic PVL) were reviewed. Sonography was compared with computed tomography (CT) where applicable. In this series 4.8% of all neonates referred from an intensive care nursery developed cystic PVL. Hemorrhagic and nonhemorrhagic forms were observed. Sonography depicted both forms as strong periventricular echoes. Small cysts developed in the subacute phase. CT was unreliable in diagnosing the nonhemorrhagic form of PVL and had a tendency to miss the development of white-matter cysts. Sonography proved to be an excellent method for establishing the initial diagnosis and recognizing late sequelae. Late CT changes consisted of periventricular cysts, irregularity of the ventricular wall, ventricular enlargement, and cerebral atrophy.