This study has shown that irrespective of the underlying aetiology, early indications for HPHC (derived from concurring ventriculomegaly and macrocephaly) are accompanied by pro-inflammatory cytokine activation (IL-18 and IFNγ) with highest IL18 concentrations in post-hemorrhagic HPHC. The gene discussed is IL18; the disease is Ventriculomegaly.