Diagnostic accuracy of neonatal structural MRI scores to predict 6-year motor outcomes of children born very preterm.

AIMS

This study aimed to (1) evaluate associations between Early and Term structural MRI (sMRI) brain abnormality scores and adverse motor outcomes at 6-years corrected age (CA), (2) determine their diagnostic accuracy in predicting adverse motor outcomes and cerebral palsy (CP) at 6-years CA.

METHODS

Infants born < 31-weeks gestational age (GA) returning for 6-year follow-up were included. Early and Term sMRI were scored using a validated method, deriving white matter, cortical grey matter, deep grey matter, cerebellar and global brain abnormality scores (GBAS). At 6-years CA, Movement Assessment Battery for Children-2nd Edition (MABC-2) was administered. Linear regression assessed associations between Early and Term GBAS/subscale scores and 6-year MABC-2 total score. For diagnostic accuracy, sMRI scores were categorised as none/mild vs moderate/severe, MABC-2 cut-off ≤ 5th percentile, and CP as present/absent.

RESULTS

Infants had Early MRI (n = 123) at mean PMA 32.5-weeks (median GA 28.4-weeks; mean birthweight 1101 g) and n = 114 had Term MRI (Mean PMA 40.8-weeks). Nine had CP and n = 116 had MABC-2 scores. Early (B: -1.92; p ≤ 0.001) and Term (B: -1.67; p ≤ 0.01) GBAS were negatively associated with MABC-2 scores. Both Early and Term GBAS had high specificity (Sp) and low sensitivity (Se) in predicting MABC-2 ≤ 5th percentile (Early: Se 36 %, Sp 82 %; Term: Se 28 %, Sp 93 %) and predicted CP with high Se and Sp (Early: Se 78 %, Sp 78 %; Term: Se 75 %, Sp 89 %).

CONCLUSION

High Sp of Early and Term MRI predicting an outcome on MABC-2 may help accurately identify infants unlikely to develop motor impairments at 6-years CA.