Why does sunset sign occur in Hydrocephalus in children?

Question

Sun set sign is seen in children with big head due to hydrocephalus and I think its invariable finding in severe cases.
What is the cause of sunset sign?

Answer 1

In hydrocephalus, eyes might deviate downward because of impingement of the dilated suprapineal recess on the tectum, producing the setting-sun eye sign. The "setting sun" sign is an ocular abnormality where the eyes appear to look downward such that the whites of the sclera form an arc above the irises.