AQP4 and Ventriculomegaly: A previous study using aged animals exposed to Hx showed the development of a hydrocephalic condition that reproduced fundamental pathophysiological features of patients with iNPH, such as ventriculomegaly, elevation of intracranial pressure, cognitive impairment, and reduced CSF drainage and ventricular distensibility, with clear participation of AQP4 in the CSF ventricular overload during the hypoxic event [19].