title: Acoustic and perceptual aspects of vocal function in children with adenotonsillar hypertrophy--effects of surgery.
abstract: OBJECTIVE
  To evaluate outcome of two types of tonsil surgery (tonsillectomy [TE]+adenoidectomy or tonsillotomy [TT]+adenoidectomy) on vocal function perceptually and acoustically.
  
  
  METHODS
  Sixty-seven children, aged 50-65 months, on waiting list for tonsil surgery were randomized to TE (n=33) or TT (n=34). Fifty-seven age- and gender-matched healthy preschool children were controls. Twenty-eight of them, aged 48-59 months, served as control group before surgery, and 29, aged 60-71 months, served as control group after surgery.
  
  
  METHODS
  Before surgery and 6 months postoperatively, the children were recorded producing three sustained vowels (/ɑ/, /u/, and /i/) and 14 words. The control groups were recorded only once. Three trained speech and language pathologists performed the perceptual analysis using visual analog scale for eight voice quality parameters. Acoustic analysis from sustained vowels included average fundamental frequency, jitter percent, shimmer percent, noise-to-harmonic ratio, and the center frequencies of formants 1-3.
  
  
  RESULTS
  Before surgery, the children were rated to have more hyponasality and compressed/throaty voice (P<0.05) and lower mean pitch (P<0.01) in comparison to the control group. They also had higher perturbation measures and lower frequencies of the second and third formants. After surgery, there were no differences perceptually. Perturbation measures decreased but were still higher compared with those of control group (P<0.05). Differences in formant frequencies for /i/ and /u/ remained. No differences were found between the two surgical methods.
  
  
  CONCLUSIONS
  Voice quality is affected perceptually and acoustically by adenotonsillar hypertrophy. After surgery, the voice is perceptually normalized but acoustic differences remain. Outcome was equal for both surgical methods.
authors.affiliation: Division of Speech and Language Pathology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden. inger.lundeborghammarstrom@liu.se
authors.forename: Inger
authors.initials: I
authors.lastname: Lundeborg
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Hultcrantz
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Ericsson
authors.forename: Anita
authors.initials: A
authors.lastname: McAllister
mesh_terms: D000233:Adenoidectomy; D000234:Adenoids / Q000473:pathology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006984:Hypertrophy / Q000503:physiopathology / Q000601:surgery; D008297:Male; D014066:Palatine Tonsil / Q000473:pathology* / Q000601:surgery; D010608:Pharyngeal Diseases / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D011184:Postoperative Period; D057234:Preoperative Period; D012737:Sex Factors; D013061:Speech Acoustics; D014068:Tonsillectomy; D014831:Voice / Q000502:physiology*; D014833:Voice Quality