Ventriculomegaly is a brain condition that occurs when the lateral ventricles become dilated. The most common definition uses a width of the atrium of the lateral ventricle of greater than 10 mm. This occurs in around 1% of pregnancies. When this measurement is between 10 and 15 mm, the ventriculomegaly may be described as mild to moderate. When the measurement is greater than 15mm, the ventriculomegaly may be classified as more severe. In your case it is 7 mm and it is of not much concern, but follow your doctor advice and go for a 4D scan. In this scan they might pick up more details of any anomalies if present. Ventriculomegaly is also known to be associated with other malformations such as agenesis of the corpus callosum, spina bifida, and heart defects. Fetuses with both isolated ventriculomegaly and with other anomalies have an increased risk of having a chromosomal abnormality, including that of Down Syndrome. I think you need not worry much about this All the best Dr Santosh