Things which I notice: the left nipple is a lot higher than the right, the creases under the breasts are pretty even, the overall shape is O.K., right areola and breast seems a little larger, the left seems to be bottoming out more, and you state they are silicone gel implants, but put 550-590 (which seems to indicate saline filled implants". When you lift the breasts, you still end up with skin (on the bottom of the breasts) which has previously been stretched and does not have the same holding power as "normal" skin. I think "roundness" on the top is achieved by overfilling saline implants, and not usually with gel. I would suggest you do nothing at this time. The sagging will continue and there will be less "roundness". When you decide to do something, I would consider doing a minimal reduction on the right (to try and even the size); if saline, slightly overfill the same implants; repeat the peri-areolar and vertical lift on the right, making the areola smaller; and take some skin out vertically on the left. If there was a horizontal scar in the creases, it may need adjustment. Good luck .
O'Neil Engeron, M.D.