Thanks for your query.
Ventricular dilatation with hypoplasia
of the inferior vermis of cerebellum
is a group of disorders which has a varied presentation.
It ranges from severe life threatening forms, to ones which are compatible with life.
Leading causes are Dandy Walker syndrome , Joubert syndrome
This condition is associated with other chromosomal abnormalities in upto 50 - 80 % of cases.
You should have an expert sonogram to rule out other anomalies.
If diagnosed early enough, amniocentesis
to rule out other syndromes could have been done.
Please consult a Genetic and Fetal Medicine Expert at the earliest, to evaluate the ultrasound
, other risk factors present in the mother / family and to undergo further tests as suggested .