Enlarged Ventricles at 21 week scan

[erriechick]

Hi there, due to high AFP result (5.6) I was scanned at 16 weeks for spina bifida. At 16 weeks no abnormalities were seen and was back for a scan yesterday at 21 weeks. Again no abnormalities were seen, however the space in the baby's head was 11.6 (above "normal" of 10mm). As you can imagine I am extremely upset, scared that the baby may develop hydrocephalus if the space gets bigger between now and the next scan - in 3 weeks time! Anyone else gone through similar?