Lindie, all I will say is that they tell us way too much these days and mostly they are things that will resolve themselves and they're only mentioning it because of people suing.
I was told at my 20 week this time around, that my baby had choroid plexus cysts on her brain. It was such an awful time because I made the mistake of searching the internet to learn about it. BIG MISTAKE... I then had to wait 5 weeks before they could do another u/s to see if they'd gone.
What I read said it could be part of downs syndrome or trisomy 18. What I have since found out is that it is quite common (in 2% of babies, this is common apparently) and that they pretty much always resolve themselves. AND in baby's with trisomy etc they don't all have the cystts anyway.
So basically it was a horrible and scary time, and I can understand that you're probably feeling that now. The best advice I can give is not to look on the net, but to ring your Dr or midwives and say you're worried. I was so calmed down by them. There is also a line at some hospitals that deal with problems in unborn babies, as sort of a counselling line. I was recommended to ring, mainly so they could tell me it was nothing to worryabout.
Best of luck and I hope you can relax xoxoxo