Aesthetic surgeons in the business of facial wrinkle reduction have noted that if one weakens the glabella muscle with injections of AbobotulinumtoxinA without also weakening the frontalis muscle, unwanted side effects can occur. Known in the trade as ‘Spock,’ ‘Joker,’ or ‘Mephisto’ eyebrows. These side effects can be avoided by also injecting the fontalis muscle […]