Are 5 flourauricil benefits for scars long lasting?

Hello I had an upper eyelid surgery 2 years ago which healed with a very raised ugly scar. Seven months post op, I found out about 5 fu & had an injection. Now scar is much better than it was however still a bit raised and I want to excise and revise.. I noticed that it seems I have more skin on eyelid after 5 fu injection and scar is also looser and more pliable. So I'm wondering--Will this injection I had provide any benefits for scar revision? Skin is much more lax than it was before.