The effects of blepharoplasty are long lasting and you should be able to enjoy your results for many years. Once skin or fat are removed, they do not grow back. Most people who have eyelid surgery do not have to repeat the procedure.
However, your eyelids will not stay exactly as they are after eyelid surgery for the rest of your life, because eyelid surgery does not stop the natural aging process. Eventually your eyes will start to show signs of aging.