title: Analysis of Temporal Change in Voice Quality After Thyroidectomy: Single-institution Prospective Study.
abstract: OBJECTIVE
  This study analyzed the temporal changes of voice quality after thyroidectomy and assessed the predictive perioperative parameters of postthyroidectomy voice disorder (PTVD).
  
  
  METHODS
  This is a prospective cohort study.
  
  
  METHODS
  From March 2011 to July 2014, 559 patients who underwent thyroidectomy with or without central neck dissection were prospectively enrolled. All patients underwent prospective voice evaluation using the subjective and objective comprehensive battery of assessments, preoperatively and postoperatively at 1 week, 1 month, 3 months, 6 months, and 12 months.
  
  
  RESULTS
  Fundamental frequency (F0) was not significantly decreased during the postoperative follow-up. Maximal vocal pitch (MVP) and maximal intensity were not recovered, even at 1 year postoperatively, whereas the Grade, Roughness, Breathiness, Asthenia, Strain scale reached preoperative value at postoperative 3-6 months and voice handicap index at 1 year. Postoperative 1-month MVP was the best predictor for PTVD, and the cut-off value was 80% of preoperative value. Wide surgical extent and high preoperative F0 were the parameters that significantly correlated with PTVD (P = 0.021 and P < 0.001, respectively), and large tumor, higher preoperative MVP, and lower postoperative 1-month F0 were significantly associated with permanent PTVD (P = 0.028, P < 0.001, and P = 0.003, respectively).
  
  
  CONCLUSIONS
  Different recovery patterns of voice parameters should be considered in preoperative counseling. Intensive voice therapy may be needed for patients with the ability to produce higher pitch than normal preoperatively and wide surgical extent.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Doh Young
authors.initials: DY
authors.lastname: Lee
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Ki Jeong
authors.initials: KJ
authors.lastname: Lee
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Soo Min
authors.initials: SM
authors.lastname: Hwang
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Kyoung Ho
authors.initials: KH
authors.lastname: Oh
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Jae-Gu
authors.initials: JG
authors.lastname: Cho
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Seung-Kuk
authors.initials: SK
authors.lastname: Baek
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Soon-Young
authors.initials: SY
authors.lastname: Kwon
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.
authors.forename: Jeong-Soo
authors.initials: JS
authors.lastname: Woo
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea.. Electronic address: kyjungmd@gmail.com.
authors.forename: Kwang-Yoon
authors.initials: KY
authors.lastname: Jung
mesh_terms: D000162:Acoustics; D000328:Adult; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D037981:Neck Dissection / Q000009:adverse effects; D017060:Patient Satisfaction; D011446:Prospective Studies; D020127:Recovery of Function; D056910:Republic of Korea; D012649:Self Concept; D013061:Speech Acoustics; D013067:Speech Perception; D013068:Speech Production Measurement; D013965:Thyroidectomy / Q000009:adverse effects*; D013997:Time Factors; D016896:Treatment Outcome; D014832:Voice Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D014833:Voice Quality
keywords: fundamental frequency; maximal vocal pitch; papillary thyroid carcinoma; thyroidectomy; voice