5 1/2 week post FUE and the sides of donor area are clearly thinner, will this improve?

It can take 6 to 12 months after surgery to see results.  If you are concerned it is best to contact your doctor.  It is not clear if your thinning will improve based on photos alone.

You have to give it some time to see if it will improve.  It may be shock loss, it may also have been over harvested in that area.  It's important when doing an FUE you spread the wealth and not get greedy and harvest from area of the scalp where its easy.

Hi, Piet--I agree: there clearly is noticeable thinning in the donor area at a time when the shaved hairs would normally have regrown. This could possibly be the result of over-harvesting outside the SDA ("safe donor area") where the "permanent" hair can be less so, and there may already have been some miniaturization. At any rate, this is just speculation--time will tell. You may need to let your hair grow long enough to help mask the thinning......in which case, you could have had an FUT procedure  which likely would have left you with an undetectable linear scar in the center of the safe donor area.Thanks for your question--I hope this helps.Dr. Ballon

How many grafts did you have done in this and previous sessions?  This is important information to know as it will tell much me if the thin areas will regrow or not.