A patient comes to your office requesting cosmetic Botox. She is bothered by the wrinkles in the area depicted in the image. Which muscle would you need to target with your injections to address these rhytides?

Correct Answer: frontalis

The frontalis muscle is responsible for elevation of the forehead and produces horizontal wrinkles across the forehead. Contraction of the corrugators and procerus is responsible for the vertical glabellar lines between the brows. The orbicularis oculi muscle is a concentric muscle around the eye that upon contraction produces the classic 'crow's feet' seen at the lateral canthal area.