title: Functional outcome of vocal fold medialization thyroplasty with a hydroxyapatite implant.
abstract: OBJECTIVE
  Unilateral vocal fold paralysis can cause a persistent incomplete glottal closure during phonation, resulting in impaired voice function. The aim of this study was to evaluate functional results of medialization thyroplasty using a hydroxyapatite implant (VoCoM).
  
  
  METHODS
  Prospective observational cohort study.
  
  
  METHODS
  Between 1999 and 2003, a total of 26 patients (19 men, 7 women) undergoing medialization thyroplasty using a hydroxyapatite implant because of unilateral vocal fold paralysis were enrolled in the study. To evaluate voice function, the following parameters were measured preoperatively and postoperatively: mean fundamental frequency, mean sound pressure level, frequency and amplitude range (voice range profile), and maximum phonation time. A perceptual assessment of hoarseness was conducted using the Roughness, Breathiness, Hoarseness scale. Furthermore, the magnitude of voice related impairment of the patient's communication skills was rated on a 7-point scale. A combined parameter called the Voice Dysfunction Index (VDI) was used to rate vocal performance.
  
  
  RESULTS
  All patients showed a statistically significant improvement in the VDI, in perceptual voice analysis, in maximum phonation time, and in the dynamic range of voice. One patient experienced a postoperative wound hemorrhage as a minor complication. No further complications or implant extrusions were observed.
  
  
  CONCLUSIONS
  Medialization thyroplasty using a hydroxyapatite implant is a secure and efficient phonosurgical procedure. Voice quality and patient satisfaction improve significantly after treatment.
authors.affiliation: Clinic of Otorhinolaryngology, Head and Neck Surgery, University Hospital Zurich, Switzerland. cstorck@uhbs.ch
authors.forename: Claudio
authors.initials: C
authors.lastname: Storck
authors.forename: Meike
authors.initials: M
authors.lastname: Brockmann
authors.forename: Elvira
authors.initials: E
authors.lastname: Schnellmann
authors.forename: Sandro J
authors.initials: SJ
authors.lastname: Stoeckli
authors.forename: Stephan
authors.initials: S
authors.lastname: Schmid
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001672:Biocompatible Materials / Q000627:therapeutic use*; D017886:Durapatite / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care; D011183:Postoperative Complications; D011300:Preoperative Care; D019736:Prostheses and Implants; D013961:Thyroid Gland / Q000601:surgery*; D016896:Treatment Outcome; D014826:Vocal Cord Paralysis / Q000209:etiology* / Q000601:surgery*; D014832:Voice Disorders / Q000175:diagnosis / Q000209:etiology; D014833:Voice Quality
chemical_list: D001672:Biocompatible Materials; D017886:Durapatite