Alzheimer's
Stroke
Parkinson's disease
Electrolyte abnormality
Malignancy
Uremic encephalopathy<unk>  ex vacuo (diffuse cerebral atrophy on CT)
Normal pressure hydrocephalus
Alzheimer's
Dementia with Lewy bodies
Stroke
Prion disease
Parkinson's disease
Multiple sclerosis
Electrolyte abnormality