title: Vibratory onset and offset times in children: A laryngeal imaging study.
abstract: OBJECTIVE
  The aim of the study was to evaluate the differences in vibratory onset and offset times across age (adult males, adult females, and children) and waveform types (total glottal area waveform, left glottal area waveform, and right glottal area waveform) using high-speed videoendoscopy.
  
  
  METHODS
  In this prospective study, vibratory onset and offset times were evaluated in a total of 86 participants. Forty-three children (23 girls, 18 boys) between 5 and 11 years and 43 gender matched vocally normal young adults (23 females and 18 males) in the age range (21-45 years) were recruited. Vibratory onset and offset times were calculated in milliseconds from the total, left, and right Glottal Area Waveform (GAW). A two-factor analysis of variance was used to compare the means among the subject groups (children, adult male, and adult female) and waveform type (total GAW, left GAW, right GAW) for onset and offset variables. Post hoc analyses were performed using the Fishers Least Significant Different test with Bonferroni correction for multiple comparisons.
  
  
  RESULTS
  Children exhibited significantly shorter vibratory onset and offset times compared to adult males and females. Differences in vibratory onset and offset times were not statistically significant between adult males and females. Across all waveform types (i.e. total GAW, left GAW, and right GAW), no statistical significance was observed among the subject groups.
  
  
  CONCLUSIONS
  This is the first study reporting vibratory onset and offset times in the pediatric population. The study findings lay the foundation for the development of a large age- and gender-based database of the pediatric population to aid the study of the effects of maturation of vocal fold vibration in adulthood. The findings from this study may also provide the basis for evaluating the impact of numerous lesions on tissue pliability, and thereby has potential utility for the clinical differentiation of various lesions.
authors.affiliation: Department of Speech and Hearing Sciences, Indiana University, 200 S. Jordan Avenue, C145, Bloomington, IN 47405-7002, United States. Electronic address: patelrir@indiana.edu.
authors.forename: Rita R
authors.initials: RR
authors.lastname: Patel
mesh_terms: D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007828:Laryngoscopy; D008297:Male; D008875:Middle Aged; D010699:Phonation; D011446:Prospective Studies; D013997:Time Factors; D014732:Vibration; D014741:Video Recording; D014827:Vocal Cords / Q000473:pathology / Q000502:physiology*; D055815:Young Adult
keywords: Laryngeal imaging; Pediatric vibratory offset; Pediatric vibratory onset