Silicone gel may be helpful for scarring

It is hard to say based on your description as a "visible" scar can mean many things (e.g. Is it raised? Red? Wide? Flat?). But either way, silicone gel is known to help with scarring. In your particular case, I believe gentle regular scar massage may also help.  You should discuss this with your surgeon so he can instruct you properly on technique!  It is very unusual for lower eyelid scars to heal poorly, and typically, time will sort it out and your scar should fade regardless of how you treat it now.