The key differentials in this case are normal pressure hydrocephalus (NPH) and sodium valproate encephalitis. The clinical and imaging findings however point towards a diagnosis of vascular dementia. The MRI shows a lot of white matter change. The ventricles are widened. Of note, and against the diagnosis of NPH is that he has a patent cerebral aqueduct and his callosal angle measured in the coronal plane is within the lower limits of normal.