title: Lateral oblique forehead lines: redefining sleeping lines and treatment with botulinum toxin A.
abstract: BACKGROUND
  Lateral oblique forehead lines had previously been defined as "sleeping lines." We present arguments to support the premise that these lines are not caused by sleeping position, but arise instead from the repeated contraction of powerful frontalis and orbicularis oculi muscles and can therefore be successful treated with onabotulinum toxin A.
  
  
  OBJECTIVE
  To understand the causes behind the development of lateral oblique forehead lines and to look at treatment outcomes using onabotulinum toxin A.
  
  
  METHODS
  An examination of facial anatomy and physical laws that could influence the formation of lateral oblique forehead lines was performed. Case studies of two male subjects presenting with these lines and treated with onabotulinum toxin A are discussed.
  
  
  RESULTS
  Lateral oblique forehead lines were shown to be the result of muscular contraction rather than sleeping position. There were positive esthetic results in the appearance of these forehead lines in the two patients treated with onabotulinum toxin A.
  
  
  CONCLUSIONS
  This new definition of lateral oblique forehead lines is important because it allows for the possibility of treating overactive muscular activity with onabotulinum toxin A thereby diminishing the appearance of the lines.
authors.affiliation: Aalst Dermatology Clinic, Aalst, Belgium.
authors.forename: Koenraad
authors.initials: K
authors.lastname: De Boulle
authors.forename: Mohammed G
authors.initials: MG
authors.lastname: Turkmani
mesh_terms: D019274:Botulinum Toxins, Type A / Q000008:administration & dosage*; D003357:Cosmetic Techniques; D005152:Facial Muscles / Q000033:anatomy & histology / Q000502:physiology*; D005546:Forehead; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction; D009465:Neuromuscular Agents / Q000008:administration & dosage*
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A