Thanks for your question. For small implants axillary incisions can be used and often very hard to see scars. It can however sometimes be difficult to properly position the implant and release muscle. The axillary approach also has higher infection rates. It is unusual to see bad scars with the infra-mammary incision and this has less infection rate and allows easier positioning of the implant.
Thanks for your question. I think you would get a good result from both upper and lower lids. If however you are uncertain they can always be done as seperate procedures but I would recommend commencing with the upper lids first. This is the most predictable, reliable, and safe procedure.
Thanks for your question. One of the problems with different sized implants is the larger implant is placed in a smaller tighter envelope and the smaller implant put in a larger looser envelope. This can paradoxically make the asymmetry worse as the larger tighter breast sits higher and the looser smaller implant sits lower. Sometimes it is better to accept a small amount of asymmetry and use the same size implants. Your asymmetry on 3D imaging does not look extreme to me and I would probably agree with the advice you have been given.
Thanks for your question. Arcus release is the first step in improving tear trough however it must be combined with release of the ligament between the two muscles in the area and then usually draping of some fat from behind the orbital septum. It's extremely important then that the lower eyelid is suspended to avoid a pull down lid after these structures are released.