My son has lissencephaly. for last 2 weeks, he wakes up screaming crying and hysterical and i cant do anything to calm him down. whats causing this?

?hydrocephalus: How old is your son? How severe is his lissencephaly? When was his last head imaging study? Does he have any hydrocephalus? I would be worried that his screaming/crying are occurring because of a headache. Any headache that wakes a child up can be concerning for increased intracranial pressure. I would contact your son's primary care doctor and/or neurologist and have him examined.

Lissencephaly: lissencephaly has problems with neuronal migration. It increases risk of seizures. You want to ask you pediatrician to get EEG to rule out seizure disorder that medications might help