MAPT and normal pressure hydrocephalus: 41 patients with a typical clinical and MR-/CT-morphological presentation of NPH divided into an Alzheimer-negative (AD–, n = 25) and an Alzheimer-positive (AD+, n = 16) group according to neurodegenerative biomarkers (S100 protein, neuron-specific enolase, β-amyloid 1–42, Tau protein, phospho-Tau, protein-level and CSF pressure) in CSF.