Brief Answer:
Significant only if there are symptoms.

Detailed Answer:
I read your question carefully and I understand your concern. I also read some of the past exchanges you have had with other doctors.

I am not sure what do you mean by prognostic significance. That is because that term does not mean a disease, does not mean a diagnosis. It simply means that the observer has the impression that the spaces between the brain folds are wider than usual which might indicate that there is some degree of brain shrinking.
Now first of all that is somewhat subjective, especially if mild, as there is no measure to express that, it is not measured in ml or cm, there are no approved normal values. So if shown to different radiologists they might even not agree there is such shrinking of the brain. In fact the french report doesn't mention it at all, considers size of ventricles and spaces as normal (my french comprehension is pretty good and I've spent a couple of months in the one of the most prominent French hospitals).
Even if we admitted that there is sulcal widening, that is a phenomena which happens in all individuals. All of us after the third decade of life lose a percentage of brain mass each year and sooner or later that will show through widening of the sulci and enlargement of the ventricles. That is how the brain ages, but that doesn't mean it represents any threat, it is like saying that one has early wrinkling of the skin for his/her age, it is not good but it is not a threatening condition, some people age earlier than others, the same applies to the brain, that is what was meant by normal variant. That is why it becomes significant only if there are manifestations of dementia like memory, speech, judgment issues, difficulty in performing higher mental functions.

Now I do not say that it is perfectly fine. If present it might mean that over the years your brain performance is prone to decline more quickly, that you are more prone, have a higher risk to develop dementia in say 30 years. That is why I am not providing reference saying it is fine, you have a higher risk. However having a higher risk doesn't mean you will develop it, there are so many other factors influencing over the years, like healthy lifestyle, education, other conditions like hypertension diabetes etc. And it certainly does not represent any threat to your current well being rest assured about that.

One other factor, I notice that the french report speaks of a maniacal episode. I do not know whether it was an isolated event, however if you also suffer from mood disorders like depression or bipolar disorder you should know that studies have shown that cortical sulcal widening is more common in such patients, so that may be a factor as well if it is your case.

I remain at your disposal for other questions.

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Brief Answer:
Read below.

Detailed Answer:
Hello again! Sorry for answering a little late but I was on the move and it is not possible to open the mri images in the dicom format on my smartphone, had to wait till I got hold of a PC.

The fact that the CT done before the french MRI spoke of atrophy while the mri didn't, reinforces what I said about it being a subjective evaluation as there are no measuring parameters, it's an impression of the observer which can be subjective. So we don't make evaluations based on images but on patients manifestations.

Speaking of my personal impression on the available MRI, I thought there was mild widening of the sulci as well. Whether that represents any near term threat, I maintain that it doesn't for the reasons I already explained, but it might be associated with a higher risk of dementia later on in life as age advances. But as I said that is affected by many factors overs the years such as lifestyle, high blood pressure, diabetes, inheritance etc. And higher mental functions do not correlate completely with gross brain mass, the brain mass doesn't tell us about the number of connections and performance of the cell. So even when there are manifestations it is through appropriate neuropsychological tests which determine whether cognitive functions are impaired or not, not MRIs.

Saying widening of the sulci is the same with atrophy, it's not that one cause the other, only different ways to describe it. What I suppose you had in mind when you ask whether congenital or a result of atrophy is whether it's something which is finished now, or whether it is an evolving process, a progressive atrophy. The answer is yes, it is possible to be as a result of a problem present before birth or early infancy, such as ischemia, infection, past trauma. But unfortunately there is no certain way of determining that now though, only watching evolution over the years.

As for the arachnoid cysts being the cause, no, that is not the case. Regarding the maniac episode, if an isolated transitory one shouldn't be the cause, it is the cause when there are long standing mood disorders.

I hope to have been of help.

P.S. While you do not have to worry about me or the moderators here, I believe that the conversations here may be viewed by other people on the net, so I would change the google password if I was you in order to avoid some stranger being able to access your account and the info on the drive.

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