Little is known about the clinical evolution and neurologic sequelae of transient periventricular echodensities in the neonatal period. The aim of our study was to assess the neurodevelopmental outcome in preterm infants with transient periventricular echodensities. Cerebral ultrasonography was performed within the first 72 hours of life on all preterms with a < or = 37 weeks' gestational age who were admitted consecutively to the Neonatal Intensive Care Unit of the University of Parma from January 2001 to December 2002. Cerebral ultrasonography was performed at least twice within the 14th postnatal day and was repeated weekly until 40 weeks' postconceptional age. Transient aspecific echodensities were defined as areas in the periventricular region brighter than the choroid plexus persisting less than 14 days. One hundred sixty-four preterm infants were selected and divided into three groups: (1) 78 preterm infants without ultrasound abnormalities, (2) 50 preterm infants with transient periventricular echodensities, and (3) 36 preterm infants with persistent echodensities. Developmental outcome was assessed at 44 weeks' postconceptional age, after 1 month from the discharge and at the corrected ages of 3, 6, 9, and 12 months using the Griffiths Mental Developmental Scale. Group 1 and 2 infants showed normal neurodevelopment in 88.5% and 94% of cases, respectively, whereas the preterm infants belonging to group 3 had a favorable outcome in 22.2% (P < .001) of cases only. In conclusion, our study demonstrates how infants with transient echodensities show a neurodevelopmental outcome that is entirely identical to infants with a steadily negative ultrasound finding.