title: Glottal gap as an early predictor for permanent laryngoplasty in unilateral vocal fold paralysis.
abstract: OBJECTIVE
  To assess the possible predictive factors for permanent laryngoplasty (PL) in patients with acute unilateral vocal fold paralysis (UVFP), and to assess the effects of early vocal cord hyaluronic acid injection.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Patients diagnosed with UVFP within the previous 6 months were enrolled. Initial and follow-up videolaryngostroboscopy, voice laboratory analysis, laryngeal electromyography, and Voice Outcome Survey were performed.
  
  
  RESULTS
  Fifty newly diagnosed UVFP patients were recruited. Eight were excluded after 12 months of follow-up and data for 42 patients were analyzed. In patients treated conservatively, the glottal gap was measured on presentation. Normalized glottal gap area (NGGA) was the only predictor of PL (P = 0.036) according to multivariate logistic regression analysis. A cutoff value of 7.36 resulted in sensitivity of 85.7% and specificity of 80.0% for predicting future PL. The PL rate was significantly higher in patients with an initial NGGA > 7.36 compared with ≤ 7.36. (6/9 vs. 1/13; χ(2) = 6.71; P = 0.010). Among patients with an initial NGGA > 7.36, those who accepted early hyaluronic acid injection had a significantly lower rate of PL (1/11 vs. 6/9; χ(2) = 7.21; P = 0.007) and better social and emotional role functioning at follow-up.
  
  
  CONCLUSIONS
  The glottal gap on presentation is a robust early predictor of PL. Early, office-based hyaluronic acid intracordal injection can reduce the need for PL in patients with a large NGGA.
authors.affiliation: Department of Otolaryngology, Chang Gung Memorial Hospital at Taipei, Taipei.
authors.forename: Tuan-Jen
authors.initials: TJ
authors.lastname: Fang
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Pei
authors.forename: Hsueh-Yu
authors.initials: HY
authors.lastname: Li
authors.forename: Alice M K
authors.initials: AM
authors.lastname: Wong
authors.forename: Hui-Chen
authors.initials: HC
authors.lastname: Chiang
mesh_terms: D000208:Acute Disease; D005260:Female; D005544:Forecasting; D005931:Glottis / Q000033:anatomy & histology*; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D007267:Injections; D058753:Laryngoplasty; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014826:Vocal Cord Paralysis / Q000628:therapy*
chemical_list: D006820:Hyaluronic Acid
keywords: Unilateral vocal fold paralysis; Voice Outcome Survey; glottal gap; hyaluronic acid; injection laryngoplasty