The Mixto helps to tighten the skin of the lower eye by placing hundreds of microscopic pinholes of heat into the tissue that ablate. This means that every small pin-sized hole of tissue is removed. As the skin heals over the next few days, the tissue surrounding that hole fills in and thereby contracts the surrounding skin. Heating the tissue in this way, also helps to promote new collagen fibers that help give the crepey tissue under the eye more elasticity- so you can see that the Mixto is very effective in producing improvement in the eyelid skin's appearance....
Having said that, I'm not sure I can agree with the doctor who told you you would not benefit from surgery. Without an exam it is difficult to be sure, but from the photo you posted, it looks like you have a bag under your eyes.... Depending on what is causing this appearance in you (there are several possibilities and an exam would be necessary to understand the cause in any individual), treatment might optimally include some combination of eyelid surgery, Mixto laser treatment, and/or injection of fillers.
The only way to have your question answered is to visit with a surgeon you like and can trust and proceed with a plan that makes sense to you.
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