Brief Answer:
No worrying findings

Detailed Answer:
I read your question carefully and I understand your concern.

That finding speaks of mild volume loss, or shrinking of the brain to say it in more plain terms. Everyone one of us has some volume loss after the twenties, we all lose some brain cells. At first it's not visible but as the years go by this phenomenon becomes visible on imaging. To a certain degree it is part of aging, brain ages like every other organ. So the interpretation of that finding depends on the patient age and clinical findings. For a 20 year old mild atrophy might be worrying, after the age of 65 it is a very common finding in many people, it is no worrying finding in itself. As for the asymmetry it meant that this process is uniform, if it was affecting only certain lobes it might indicate a certain type of dementia like the temporal lobe in Alzheimer's. As for not having an intracranial process it means simply no brain lesion like tumor, infection, stroke etc.

Now of course imaging alone doesn't make the diagnosis, the atrophy doesn't have an exact relationship with cognitive function, there are cases of dementia where atrophy is not marked in the initial stages and vice versa there are people with marked atrophy who perform well on cognitive tests. So to say whether you have Alzheimer's or not imaging is not enough, neuropsychological tests to evaluate your cognitive functions are also necessary, like the MMSE (mini mental state exam) to name a simple one. If you have had such tests and they resulted normal then that coupled with the mild atrophy, acceptable for your age, then one can say you have no Alzheimer's. It's the tests which provide an objective estimation of your cognition, because in everyday life one might have the impression of having memory issues which in fact might be simply anxiety and lack of concentration.

I remain at your disposal for further questions.

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