Is my hair will grow back in the donor area? I had FUE 4000 grafts 45 days ago. (photo)

Thanks for the question.
It is difficult to comment thoroughly from the picture provided, but there are multiple reasons to have patches post-transplant. The most likely culprit is shock loss.  Shock loss is common and typically transient.  PRP injections and Light therapy can help prevent this. But there are also technical reasons to have patches.  It would be good to know how densely your grafts were placed (for instance, over how big of an area were the grafts placed).  When doing transplant, it is important to place the grafts such that they have sufficient space between them to insure good blood flow to the grafted hair.  For instance, if I place grafts too closely to one another (densely pack), then the grafts may be starving each other for blood supply and as a result some may fail. Apart from these, there are other reasons such as strenuous activity immediately after transplant.  This  can cause the follicles to swell and fail.  Other reasons such as smoking can also affect the the follicle.

Thank you for the post. Little difficult to judge from one photo. It can either be of 2 things, Shock Loss and or over-harvesting. If it is shock-loss, then it will resolve within 4 to 8 months..... Applying Minoxidil on that area, should also be of help. Best wishes.