Magnetisation transfer ratio is low in normal-appearing cerebral white matter in patients with normal pressure hydrocephalus

We measured the magnetisation transfer ratios (MTR) of normal-appearing rostral (PR) and caudal (PC) periventricular white matter, the genu (CG) and the splenium (CS) of the corpus callosum and the thalamus (TH) in 12 patients with normal-pressure hydrocephalus (NPH) and compared them with 16 healthy control subjects. We found a significantly lower MTR in the NPH group than in the normal group for PR, PC, CG, and CS but not for TH. MT measurements give additional information which cannot be gained by conventional MRI, suggesting that NPH is associated with diffuse white matter damage, even in normal-appearing cerebral white matter. (orig.)