If you are unhappy with your breast lift scars, it is important that you wait at least 6months to make sure that the scars have matured enough. Remember that they will continue to change for even a year following surgery and further intervention may not even be required. That said, microneedling can help to improve these and other scars. The addition of platelet rich plasma is unlikely to do anything more than microneedling alone except lighten your wallet. While there may be some advantages in using PRP in certain medical circumstances, I don't believe there is any science behind its use in the treatment of skin scars.