PADI4 and Hydrocephalus: Secondly, kaolin‐induced hydrocephalus rats were treated by peptidylarginine deiminase 4 (PAD4) inhibitor and DNase I. NETs, subarachnoid fibrosis, reactive gliosis, proliferation and differentiation of meningeal fibroblasts were detected by immunofluorescence and Western Blot (WB), ventricular volumes were evaluated by magnetic resonance imaging (MRI).