Inclusion of extremes of prematurity in ventricular index centile charts

Objective: To assess the relationship between ventricular index (VI) measurements and postmenstrual age in preterm infants and to generate centile charts and normal ranges for frontal horn ratio (FHR) for a large contemporary cohort of preterm infants. Study Design: A retrospective cohort study of 253 infants with birth gestation less than 32 weeks admitted between January 2009 and December 2011 to a tertiary NICU in Ireland. Results: A total of 816 cranial ultrasounds were reviewed. Data collected were grouped according to postmenstrual age at the time of scan from 23 weeks to 45 weeks. Median values for VI show a general trend to increase with gestation. FHR did not significantly change with postmenstrual age at scan with a median value of 0.31. Conclusion: There is a slight increase in VI as gestation at the time of scans increases. These results provide the basis for updated centile charts which we propose for current practice.