Linear growth of corpus callosum and cerebellar vermis in very-low-birth-weight preterm infants.

BACKGROUND/PURPOSE: Impaired growth of the corpus callosum (CC) and cerebellar vermis (CV) is associated with poorer neurodevelopmental outcomes in preterm infants. However, references on the postnatal growth rate of the CC and CV by sonography are limited. The aim of this study is to assess the normal linear growth of CC and CV using a serial cranial ultrasound.

METHODS

We prospectively enrolled preterm infants with very low birth weight from September 2008 to December 2009 after excluding those with congenital anomalies or diseases affecting the brain parenchyma. Serial sonographic measurements of the CC and CV were performed according to the standard protocol. Scheduled comprehensive neurodevelopmental evaluations were performed till the corrected age of 2 years. We excluded those with significant brain damages or poor neurodevelopmental outcomes in the final analysis. The growth rate was estimated using the loess smoothing curve and linear regression analysis.

RESULTS

Among the 86 enrolled neonates, 14 with significant brain damage and 8 with poor neurodevelopmental outcomes were excluded from the final analysis. The growth rate of the CC length was 1.72 (95% confidence interval [CI]: 1.24-2.20) and 0.57 (95% CI: 0.33-0.80) mm per week before and after the postmenstrual age of 30.5 weeks, respectively. The growth rate of the CV length was 0.78 (95% CI: 0.68-0.89) mm per week.

CONCLUSION

We proposed reference values of the normal linear growth rate of the CC and CV lengths in very-low-birth-weight preterm infants using the serial cranial ultrasound.