title: How to avoid eyelid ptosis when injecting botulinum toxin into the corrugators.
authors.forename: F D
authors.initials: FD
authors.lastname: Parsa
mesh_terms: D001763:Blepharoptosis / Q000139:chemically induced / Q000517:prevention & control*; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D005138:Eyebrows / Q000187:drug effects*; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular
chemical_list: D019274:Botulinum Toxins, Type A