title: Differential diagnosis in facial nerve palsy: a clinical review.
abstract: BACKGROUND
  The facial nerve possesses five functional components and manifests a complex course from its origin in the motor cortex to its peripheral distribution. Pathologies that impact the facial nerve in various locations along its route result in characteristic clinical manifestations that often involve other neurologic entities.
  
  
  METHODS
  Case reports of three patients who manifested lesions of the facial nerve are presented. Each case represents a specific facial nerve pathology occurring within the supranuclear, nuclear, and infranuclear location. An anatomic, regional, and etiologic approach to the spectrum of facial nerve disorders is provided. Additionally, hyperkinetic facial disorders is discussed, and the management of facial nerve palsy is emphasized.
  
  
  CONCLUSIONS
  The clinician must understand the fundamental anatomy and distribution of the facial nerve in order to localize lesions and institute the appropriate management. Abnormalities of lid position and insufficient corneal wetting are problematic. All efforts should be directed toward the maintenance of corneal integrity by appropriate wetting strategies.
authors.affiliation: Pennsylvania College of Optometry, Philadelphia, USA.
authors.forename: B H
authors.initials: BH
authors.lastname: Blaustein
authors.forename: A
authors.initials: A
authors.lastname: Gurwood
mesh_terms: D000368:Aged; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis; D003937:Diagnosis, Differential; D005152:Facial Muscles / Q000294:innervation / Q000503:physiopathology; D005158:Facial Paralysis / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged