Hidetaka Yoshihashi

Assessment of phonatory function by the airway interruption method: age-related changes.

OBJECTIVE: In order to ascertain age-related changes in phonatory function, an aerodynamic phonatory function test based on the airway interruption method was conducted. STUDY DESIGN: Subjects were 142 men and 144 women aged between 20 and 79 years. No subjects demonstrated abnormalities of sound quality. The test was conducted using the Nagashima PS77E phonatory function analyzer. Subjects were instructed to phonate at the most comfortable pitch and intensity, and fundamental frequency (F0), sound pressure level (SPL), mean flow rate (MFR), expiratory lung pressure (EP), and airway resistance were determined. RESULTS: F0 was lower among women aged ≥50 years. EP was lower for women aged ≥70 years than for those in other age groups. For both genders, airway resistance was lower for those aged ≥70 years when compared to other age groups. CONCLUSIONS: Among women, F0 was lower aged ≥50 years. In advanced age, EP and airway pressure decreased among women and airway resistance decreased among men. EBM rating: C-4

The role of adjustment of expiratory effort in the control of vocal intensity: Clinical assessment of phonatory function

OBJECTIVE: To determine the role of the adjustment of expiratory effort in the control of vocal intensity. STUDY DESIGN: An intensity-loading test was performed by using the airway interruption method. Three groups of subjects were used: a control group thought to resemble normal vocal fold closure, a group of patients with Reinkes edema thought to represent increased mass at the level of the vocal folds, and a group with vocal fold paralysis that was thought to represent a group with lack of adequate vocal fold closure. RESULTS: In the control group, expiratory lung pressure and airway resistance slightly increased. In the patients with Reinkes edema, expiratory lung pressure, and airway resistance significantly increased. In this group, the voice intensity was controlled by laryngeal adjustment, but a greater expiratory effort was needed because of a greater increase in glottal resistance. In the patients with vocal cord paralysis, airway resistance did not increase even with a high-intensity voice. Vocal intensity was controlled by expiratory effort. CONCLUSIONS: If there is sufficient ability for laryngeal adjustment, vocal intensity is controlled primarily by laryngeal adjustment and by expiratory adjustment in response to increased glottal resistance. However, vocal intensity is controlled by expiratory effort when laryngeal adjustment ability is poor.

Phonatory function of the elderly determined by intensity-loading test: A comparison with the young

Objective The goal was to test the hypothesis that the elderly have diminished laryngeal regulation capability, so we investigated phonatory function in the elderly and young using a sound pressure-loading test. Study Design and Setting In 36 healthy men (17 in their 20s, 19 in their 70s) and 45 healthy women (22 in their 20s, 23 in their 70s), fundamental frequency, sound pressure level, mean flow rate (MFR), and expiratory lung pressure (EP) were determined from phonatory function testing. Subjects phonated at a comfortable level and at high intensity, without changing vocal pitch. Results MFR, EP, and airway resistance increased with high-intensity phonation in the young; however, only MFR and EP increased in the elderly. Conclusions The findings supported our hypothesis: with high-intensity phonation, the elderly undergo unchanged laryngeal regulation but a greater degree of expiratory regulation. Significance The elderly are likely to become tired due to the effort required for phonation.

P078: Voice Assessments of Spasmodic Dysphonia

The adult group had a total number of myelin fibers at the RLN higher than the elderly group (p 0.0006), this difference happening at myelin fibers with diameters of 1-3 m (p 0.007). Superior laryngeal nerves had a higher number of myelin fibers compared to recurrent laryngeal nerves (p 0.0001). The adult group had a higher total number of fibers at laryngeal nerves (sum of superior laryngeal nerves and recurrent laryngeal nerves fibers) than the elderly group (p 0.0091). CONCLUSIONS: Total number of myelin fibers from RLN is higher for the adult group, this difference occurring at myelin fibers with a diameter 1-3 m. The adult group has a higher total number of myelin fibers at the laryngeal nerves.