Adult Hydrocephalus and the Glymphatic System.

Adult hydrocephalus, especially idiopathic normal pressure hydrocephalus (iNPH), involves cerebrospinal fluid (CSF) dysfunction that is associated with impaired waste clearance in the brain, potentially causing toxic protein buildup. This condition shares features with neurodegenerative diseases like Alzheimer's, where amyloid-β and tau proteins accumulate. Recent discoveries in the glymphatic and meningeal lymphatic systems, key in CSF and metabolic waste clearance, provide insights into these protein imbalances. However, altered CSF flow in iNPH may disrupt glymphatic transport, exacerbating protein deposits. This review proposes reframing iNPH as a cerebral "CSF-proteinopathy" disorder, although its full relationship with glymphatic impairment needs further exploration.