I agree, once a nerve is dmage it will be a permanent damage. I got a botox treatment a year ago my left eye drooped. My Dr. told me that it will wear off. thats not true once you have damaged caused to the nerves they do not send signagls for the muscles to contract as a result the muscle droops. until now my eyelids are asymatrical. may be we should tell these dr's that there wrong. once they hit the nerve, its hard to regain back the muscle functions. as a result the muscles get elongated and it droops.