title: Quantification of acute vocal fold epithelial surface damage with increasing time and magnitude doses of vibration exposure.
abstract: Because the vocal folds undergo repeated trauma during continuous cycles of vibration, the epithelium is routinely susceptible to damage during phonation. Excessive and prolonged vibration exposure is considered a significant predisposing factor in the development of vocal fold pathology. The purpose of the present study was to quantify the extent of epithelial surface damage following increased time and magnitude doses of vibration exposure using an in vivo rabbit phonation model. Forty-five New Zealand white breeder rabbits were randomized to nine groups and received varying phonation time-doses (30, 60, or 120 minutes) and magnitude-doses (control, modal intensity phonation, or raised intensity phonation) of vibration exposure. Scanning electron microscopy and transmission electron microscopy was used to quantify the degree of epithelial surface damage. Results revealed a significant reduction in microprojection density, microprojection height, and depth of the epithelial surface with increasing time and phonation magnitudes doses, signifying increased epithelial surface damage risk with excessive and prolonged vibration exposure. Destruction to the epithelial cell surface may provide significant insight into the disruption of cell function following prolonged vibration exposure. One important goal achieved in the present study was the quantification of epithelial surface damage using objective imaging criteria. These data provide an important foundation for future studies of long-term tissue recovery from excessive and prolonged vibration exposure.
authors.affiliation: Department of Otolaryngology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kojima
authors.affiliation: Department of Otolaryngology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America.
authors.forename: Mark
authors.initials: M
authors.lastname: Van Deusen
authors.affiliation: Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America.
authors.forename: W Gray
authors.initials: WG
authors.lastname: Jerome
authors.affiliation: Department of Otolaryngology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America.
authors.forename: C Gaelyn
authors.initials: CG
authors.lastname: Garrett
authors.affiliation: Department of Speech, Language, and Hearing Sciences, Purdue University, West Lafayette, Indiana, United States of America.
authors.forename: M Preeti
authors.initials: MP
authors.lastname: Sivasankar
authors.affiliation: Department of Hearing and Speech Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America.
authors.forename: Carolyn K
authors.initials: CK
authors.lastname: Novaleski
authors.affiliation: Department of Otolaryngology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America; Department of Hearing and Speech Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America.
authors.forename: Bernard
authors.initials: B
authors.lastname: Rousseau
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D004848:Epithelium / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010699:Phonation; D011817:Rabbits; D013718:Tensile Strength; D013997:Time Factors; D014463:Ultrasonography; D014732:Vibration; D014827:Vocal Cords / Q000473:pathology* / Q000648:ultrastructure