Screening Cranial Imaging at Multiple Time Points Improves Cystic Periventricular Leukomalacia Detection.

OBJECTIVE The aim of this study is to determine whether the cystic periventricular leukomalacia (cPVL) detection rate differs between imaging studies performed at different time points. DESIGN We retrospectively reviewed the prospectively collected data of 31,708 infants from the NICHD Neonatal Research Network. Inclusion criteria were infants < 1,000 g birth weight or < 29 weeks' gestational age who had cranial imaging performed using both early criterion (cranial ultrasound [CUS] < 28 days chronological age) and late criterion (CUS, magnetic resonance imaging, or computed tomography closest to 36 weeks postmenstrual age [PMA]). We compared the frequency of cPVL diagnosed by early and late criteria. RESULTS About 664 (5.2%) of the 12,739 infants who met inclusion criteria had cPVL using either early or late criteria; 569 using the late criterion, 250 using the early criterion, and 155 patients at both times. About 95 (14.3%) of 664 cPVL cases seen on early imaging were no longer visible on repeat screening closest to 36 weeks PMA. Such disappearance of cPVL was more common in infants < 26 weeks' gestation versus infants of 26 to 28 weeks' gestation (18.5 vs. 11.5%; p = 0.013). CONCLUSIONS Cranial imaging at both < 28 days chronological age and closest to 36 weeks PMA improves cPVL detection, especially for more premature infants.