The co-occurrence of idiopathic normal pressure hydrocephalus like MRI features in progressive supranuclear palsy?

I read with great interest the article by Ohara et al. [1] in which they found that progressive supranuclear palsy (PSP) patients develop idiopathic normal-pressure hydrocephalus (iNPH)-like MRI features, more than other neurodegenerative diseases. I appreciate the authors for conducting such an original study; however, I would like to make some comments for a better understanding of the report and present some crucial perspectives.