Dad, 85 was diagnosed yesterday with dementia. His doctor has ordered a brain scan. Will this tell what type of dementia he has?

The specialist evaluating my mom ordered a 3D MRI and then diagnosed her with vascular dementia (he had already said Lewy Body Dementia during a visit) saying it had shown numerous mini-strokes. We had no idea she even had any!

Not exactly, not necessarily. But it will rule out certain things, and it may show certain diagnostic other things. It certainly is worth doing.

Is your father all right with having the scan done? He's not worried about it? If he is, appeal to the radiographer to give him a little extra t.l.c. - I would expect a radiographer to have masses of experience in giving clear instructions and reassurance to anxious patients, who by the nature of the patient group may not be doing too well cognitively. And are often a bit deaf, too.

If you (like me) are given to morbid curiosity, spend some leisure time on Google typing in "Alzheimer's MRI," "vascular dementia on CT," and similar topics. This will at least give you an idea of the type and quality of information your father's doctor is aiming to get.

Not necessarily. What it will do is show what he doesn't have: strokes, tumours, hydrocephalus or other diseases that will show up in a brain scan.