I am assuming that you are referring to the redness of the scars following breast reduction/lift. I have not seen a patient with hyperpigmentation of their skin following this surgery. The redness in the scars comes from the new blood supply growing across the scar. Over time, this should fade. Generally speaking, it should take about a year to a year and a half for the scar to fully flatten, fade, and mature. Some scars may remain dark even after a sufficient time has passed. I don't really know why that happens. There are a number of scar improvement creams/treatments on the market. I'm not sure that any of them work exceptionally well. I think time is the best treatment.