Wanted to jump in on this thread to tell our story on behalf of my wife and I, as I know 1st hand how anxious a time this can be.
11 days ago we went for our 20 week scan at exactly 20 weeks all excited about finding out the sex of the baby. The scan was going fantastically well, everything seemed perfect, including as the sonographer described as a heart exactly like those in the textbooks. Baby was looked at from top to bottom, found out he was a boy and then finally right at the end she mentioned that she had spotted an area of concern that she wanted to follow up on in the baby's brain. She then took a series of measurements.
We were then seen by a consultant who tried to explain what this meant, from "it could be nothing" to "it could mean serious disabilties" to "Of course we may find other issues in a detailed scan". A measurement of 11.9mm had been recorded at the "Posterior horn of the lateral ventricles"
Obviously we were shellshocked, anxious, scared, the works.
A follow up ultrasound was arranged 3 days later with a doctor. Obviously I went home and straight onto google, bad move. Even more fear and anxiety ensued. The next 3 days were a struggle.
The follow up scan seemed to go well, no other issues were discovered, one ventricle measured around 8 mm. We had to go for a walk around the hospital to get the boy to move so they she could measure the other side. The RH ventricule was 10.6mm. (so big difference from monday) She did say everything else she saw seemed normal but obviously the one ventricle was more prominent so we would need to be reffered to a fetal medicine centre for a detailed analysis from an "expert". My wife also had bloods taken to check for any infections.
Another week of worry, although slightly encouraged by the fact the doctor found nothing else during the scan. Cue more googling and reading of MRI's and amnios etc.....more worry.
Yesterday we went to the fetal medicine centre in Birmingham. We had a detailed scan with a proffessor in fetal medicine. He explained about the ventricles and the scan procedure. Obviously we watched his every move and every measurement he took. The ultrasound equipment itself seemed much more advanced and the picture much clearer. He did the scan and stopped part way through, "Did a consultant do a detailed scan?", to which we obviously said yes......."Well, I've looked around the baby's head and done all the checks and there is nothing to suggest this is not a perfectly healthy baby, all measurements are well within normal range and everything else is developing normally" - Cue big smiles all around. He went on to do a detailed heart analysis and all was fine.
He seemed to question the validity of the other scans and in the nicest way possible, hoped he would not be seeing us again and there was no reason for us to follow up with him. The measurements were both around 8mm. I'd have to question the different quality of equipment too in all this, I'm not sure if the ventrical had reduced or it was just mismeasurements.
I just wanted to post what happened to try and help people from initially fearing the worst, like I did. These are such tiny measurements that a slight move of the curser here or there can make a dramatic impact on peoples lives.
All we wanted to do was enjoy the pregnancy and for the last 2 weeks its felt like a bit of a rollar coaster and its been difficult to put a brave face on all the baby comments from people who didnt know what we were going through. I dont know what the rest of pregnancy will bring but for now, all is good.
The torch screen will hopefully give you some answers. Please do take comfort from the experiences on this thread, chances are your little boy is absolutely fine! And his big brothers are going to absolutely dote on him 
