Once Botox Wears Off, is It Possible for the Muscle to Have Been Trained for at Least a Slight Permanent Fix?

Botox lasts for 3 to 4 months.  After than any lasting effect are from muscle retraining.  However, these wear off as well.  The precise time frame varies from person to person.  

It is possible that after several botox treatments, your muscle habits may change and the pulling up of one eyebrow may relax. Possibly your muscles may retrain themselves after only one treatment but this is not the norm. You could try one session, and try hard not to voluntarily pull up the eyebrow as the botox wears off in three to four months, not even once, and maybe this will help long term. If you find that the eyebrow goes back up the same as it was before Botox, you don't have to continue the treatments.

Tyler

I think Botox is the best option for you at this time. I understand that you don't want to get injections every 6 months, but you have to look at the alternatives.  Surgery might offer a more permanent result, but is more expensive and you might still have asymmetry.  Certainly doing nothing is also an option - so you have to weigh the expense, inconvenience and pain of injections with value of the cosmetic improvement.