Reversing a brow lift that removed muscle or fat?

Your question seem to be more theoretical in nature since you did not present any photos. You are right, most of the brow lift changes are not reversible in particular muscle activity. However, some improvement may be achieved providing that there is well defined and visible problem to be corrected. Hope this helps.

Hello, hope you are well. It depends on the type of brow lift that was performed. Some brow lifts are reversible (at least partially), and fat grafting can be performed in the upper third of the face if needed. A free muscle transfer to the brow in the context you are describing is not a feasible operation. The first step would be to obtain his operative report to see what has been done previously, all further options are somewhat dependent on that.
Best,Dr. Tower