title: Air Pressure and Contact Quotient Measures During Different Semioccluded Postures in Subjects With Different Voice Conditions.
abstract: OBJECTIVE
  The purpose of this study was to investigate the effect of phonation into tubes in air and tubes submerged in water on air pressure variables and vocal fold adduction in subjects with different voice conditions.
  
  
  METHODS
  Forty-five participants representing four vocal conditions were included: (1) subjects diagnosed with normal voice and without voice training, (2) subjects with normal voice with voice training, (3) subjects with muscle tension dysphonia, and (4) subjects with unilateral vocal fold paralysis. Participants phonated into different kinds of tubes (drinking straw, 5 mm in inner diameter; stirring straw, 2.7 mm in inner diameter; silicon tube, 10 mm in inner diameter) with the free end in air and in water. Aerodynamic, acoustic, and electroglottographic signals were captured simultaneously. Mean values of the following variables were considered: glottal contact quotient (CQ) measured by electroglottograph, fundamental frequency, subglottic pressure (Psub), oral pressure (Poral), and transglottal pressure.
  
  
  RESULTS
  All exercises had a significant effect on Psub, Poral, transglottal pressure, and CQ (P < 0.05). Phonation into a 55-cm silicon tube submerged 10 cm in water and phonation into a stirring straw resulted in the highest values for CQ, Psub, and Poral compared with baseline (repetition of syllable [pa:]) for all vocal status. Poral and Psub correlated positively.
  
  
  CONCLUSIONS
  During semioccluded exercises, most variables behaved in a similar way (same trend with a quite large individual variation) regardless of the vocal status of the participants.
authors.affiliation: School of Communication Sciences, University of Chile, Santiago, Chile; Department of Otolaryngology, Voice Center, Las Condes Clinic, Santiago, Chile. Electronic address: guzmann.marcoa@gmail.com.
authors.forename: Marco
authors.initials: M
authors.lastname: Guzmán
authors.affiliation: School of Communication Sciences, University of Valparaiso, Valparaiso, Chile.
authors.forename: Christian
authors.initials: C
authors.lastname: Castro
authors.affiliation: School of Communication Sciences, University of Chile, Santiago, Chile.
authors.forename: Sofia
authors.initials: S
authors.lastname: Madrid
authors.affiliation: Department of Otolaryngology, Voice Center, University of Chile Hospital, Santiago, Chile.
authors.forename: Christian
authors.initials: C
authors.lastname: Olavarria
authors.affiliation: Department of Otolaryngology, Voice Center, University of Chile Hospital, Santiago, Chile.
authors.forename: Miguel
authors.initials: M
authors.lastname: Leiva
authors.affiliation: Department of Otolaryngology, University of Chile, Santiago, Chile.
authors.forename: Daniel
authors.initials: D
authors.lastname: Muñoz
authors.affiliation: School of Communication Sciences, University of Valparaiso, Valparaiso, Chile.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Jaramillo
authors.affiliation: School of Education, Speech and Voice Research Laboratory, University of Tampere, Tampere, Finland.
authors.forename: Anne-Maria
authors.initials: AM
authors.lastname: Laukkanen
mesh_terms: D000162:Acoustics; D000328:Adult; D000399:Air Pressure; D000403:Airway Resistance; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D055154:Dysphonia / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D004568:Electrodiagnosis; D005260:Female; D005931:Glottis / Q000503:physiopathology*; D006801:Humans; D007101:Immersion; D008297:Male; D008875:Middle Aged; D056888:Patient Positioning; D010699:Phonation; D013997:Time Factors; D016896:Treatment Outcome; D014826:Vocal Cord Paralysis / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D014827:Vocal Cords / Q000503:physiopathology; D014833:Voice Quality; D014834:Voice Training; D014867:Water; D055815:Young Adult
chemical_list: D014867:Water
keywords: Functional dysphonia; Tube phonation; Vocal fold paralysis; Vocal semiocclusion exercises; Water resistance therapy