Characteristics of an in vivo canine model of phonation with a constant air pressure source.
Many previous studies of laryngeal biomechanics using in vivo models have employed a constant air How source. Several authors have recently suggested that the lung-thorax system functions as a constant pressure source during phonation. This study describes an in vivo canine system designed to maintain a constant peak subglottic pressure (Psub) using a pressure-controlling mechanism. Increasing levels of recurrent laryngeal nerve (RLN) stimulation resulted in a significant rise in resistance followed by a plateau. For a given Psub, flow decreased significantly and precipitously with increasing stimulation and then quickly plateaued. Vocal intensity increased with increasing RLN stimulation until a peak was reached. After this peak, intensity dropped until a plateau was reached, corresponding to the flow minimum. At a given Psub, increasing levels of RLN stimulation resulted in a normal distribution of vocal efficiencies.
Nasri
S
S
Division of Head and Neck Surgery, Stanford University Medical Center (S.N.), Stanford, Calif.
Namazie
A
A
Ye
M
M
Kreiman
J
J
Gerratt
B R
BR
Berke
G S
GS
D000403:Airway Resistance / Q000502:physiology; D000818:Animals; D004285:Dogs; D004558:Electric Stimulation; D007830:Larynx / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D010699:Phonation / Q000502:physiology*; D012123:Pulmonary Ventilation / Q000502:physiology*; D012009:Recurrent Laryngeal Nerve / Q000502:physiology; D012016:Reference Values; D013018:Sound Spectrography; D014828:Vocalization, Animal / Q000502:physiology