title: Facial nerve grading instruments: systematic review of the literature and suggestion for uniformity.
abstract: BACKGROUND
  A variety of facial nerve grading scales have been developed over the years with the intended goals of objectively documenting facial nerve function,tracking recovery, and facilitating communication between practitioners. Numerous scales have been proposed; however, all are subject to limitation because of varying degrees of subjectivity, reliability, or longitudinal applicability. At present, such scales remain the only widely accessible modalities for facial functional assessment. The authors' objective was to ascertain which scales(s) best accomplish the goals of objective assessment.
  
  
  METHODS
  A systematic review of the English language literature was performed to identify facial nerve grading instruments. Each system was evaluated against the following criteria: convenience of clinical use, regional scoring, static and dynamic measures, features secondary to facial palsy (e.g., synkinesis), reproducibility with low interobserver and intraobserver variability, and sensitivity to changes over time and/or following interventions.
  
  
  RESULTS
  From 666 articles, 19 facial nerve grading scales were identified. Only the Sunnybrook Facial Grading Scale satisfied all criteria. The Facial Nerve Grading Scale 2.0 (or revised House-Brackmann Scale) fulfilled all criteria except intraobserver reliability, which has not been assessed.
  
  
  CONCLUSIONS
  Facial nerve grading scales intend to provide objectivity and uniformity of reporting to otherwise subjective analysis. The Facial Nerve Grading Scale 2.0 requires further evaluation for intraobserver reliability. The Sunnybrook Facial Grading Scale has been robustly evaluated with respect to the criteria prescribed in this article. Although sophisticated technology-based methodologies are being developed for potential clinical application,the authors recommend widespread adoption of the Sunnybrook Facial Grading Scale as the current standard in reporting outcomes of facial nerve disorders.
authors.affiliation: Liverpool, and East Grinstead, United Kingdom; Madrid, Spain; Boston, Mass.; Los Angeles, Calif.; Durham, N.C.; St. Louis, Mo.; and Nijmegen, The Netherlands From the Facial Nerve Programme, Regional Paediatric Burns and Plastic Surgery Service, Alder Hey Children's NHS Foundation Trust, Queen Victoria Hospital Foundation NHS Trust; the Department of Otolaryngology, La Paz University Hospital; Harvard Medical School, Massachusetts Eye and Ear Facial Nerve Center; University of Southern California, House Clinic; the Division of Plastic, Reconstructive, Oral and Maxillofacial Surgery, Duke University Medical Center; Washington School of Medicine; and Radboud University Medical Centre.
authors.forename: Adel Y
authors.initials: AY
authors.lastname: Fattah
authors.forename: Anthony D R
authors.initials: ADR
authors.lastname: Gurusinghe
authors.forename: Javier
authors.initials: J
authors.lastname: Gavilan
authors.forename: Tessa A
authors.initials: TA
authors.lastname: Hadlock
authors.forename: Jeff R
authors.initials: JR
authors.lastname: Marcus
authors.forename: Henri
authors.initials: H
authors.lastname: Marres
authors.forename: Charles C
authors.initials: CC
authors.lastname: Nduka
authors.forename: William H
authors.initials: WH
authors.lastname: Slattery
authors.forename: Alison K
authors.initials: AK
authors.lastname: Snyder-Warwick
mesh_terms: D018450:Disease Progression; D005154:Facial Nerve / Q000503:physiopathology*; D005158:Facial Paralysis / Q000145:classification* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D009460:Neurologic Examination; D015588:Observer Variation; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D063189:Symptom Assessment; D014741:Video Recording