[1] WILHELMINA CHILDRENS HOSP,DEPT CHILD NEUROL,AMSTERDAM,NETHERLANDS
[2] UNIV AMSTERDAM HOSP,DEPT RADIODIAG,AMSTERDAM,NETHERLANDS
[3] UNIV UTRECHT,CTR BIOSTAT,UTRECHT,NETHERLANDS
[4] FREE UNIV AMSTERDAM HOSP,CTR DIAGNOST RADIOL & NEURORADIOL,AMSTERDAM,NETHERLANDS