I just had my 18 week ultrasound and my doc said the head is measuring more like 24 weeks, so very large and because the baby kept moving they couldnt get a clear view and could only see "minimal brain matter". Doc is very concerned and is sending me in a week or two for a higher tech ultrasound to see better. All he told me was this could potentially be serious but he doesnt know what it is at this point. Im freaking out so scared this is my fourth pregnancy, last one was a miscarriage. Please help, does anyone know what I could potentially be dealing with???