Hydrocephalous is detailed best antenately by -
Ans-DUltrasound (Ref Williams Obstetrics, 21st,p. 1119-1120).The best method for the diagnosis of hydrocephalus prenatally is ultrasound.On ultrasound, the excess fluid is reflected by ventriculomegaly.
X-ray abdomen
Amniocentasis
Clinical examination
Ultrasonography