Objective: To determine whether in fetuses with open spina bifida at 11-13 weeks' gestation the frontomaxillary facial angle is decreased.
Methods: The frontomaxillary facial angle was measured in 20 fetuses with open spina bifida and in 100 normal controls matched for crown-rump length (CRL) at 11 + 0 to 13 + 6 weeks and the values in the two groups were compared.
Results: In the control group the frontomaxillary facial angle decreased significantly with CRL from a mean of 84.0 degrees at a CRL of 45 mm to 76.5 degrees at a CRL of 84 mm (SD, 3.26 degrees). In the spina bifida group the mean frontomaxillary facial angle, corrected for CRL, was 9.9 degrees lower than in the controls and it was below the 5(th) centile in 18 (90%) of the cases (P < 0.0001).
Conclusions: In fetuses with open spina bifida at 11-13 weeks' gestation the frontomaxillary facial angle is decreased and this measurement may be useful in early screening for this abnormality.
(c) 2010 ISUOG. Published by John Wiley & Sons, Ltd.