<prompt> All are true regarding periventricular leukomalacia exceptAppear as echolucent areas cysts on neuroimaging in preterm neonate.Require atleast 2 weeks to form.Presence at birth helps to determine timing of hemorrhagic event.Cystic areas in grey matter of brain that develop after ischemic infarction.  <response>: Periventricular leukomalacia - refers to cystic areas deep in white matter of brain that develop after hemorrhagic or ischemic infarction. 