The Clinical Usefulness of Aerodynamic Test Using the Airway Interruption Method in Patients with Laryngeal Disorders / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The airway interruption method was developed as a combination of the measurement of expiratory pressure, mean air flow, intensity, and frequency. We evaluated the clinical usefulness of the airway interruption method in measuring vocal frequency, vocal intensity, mean air flow rate and expiratory air pressure. MATERIALS AND METHODS: We performed phonatory function tests in the patients with vocal nodule (n=380), vocal polyp (n=41), vocal sulcus (n=20), laryngitis (n=72), vocal paralysis (n=10) and glottic cancer, T 1 (n=5). And these results were compared with normal values which were reported previously. In 91 patients with vocal nodule and 5 patients with polyp, phonatory function test was followed up after laryngomicrosurgery and compared with preoperative test. RESULTS: In patients with vocal nodule and polyp, mean air flow rate was significantly increased (p<0.05). In polyp, these differences were greater than nodule group. In vocal paralysis, mean air flow rate was significantly increased than other groups. In glottic cancer (T1), expiratory air pressure was significantly increased than other groups. In laryngitis and sulcus vocalis, mean air flow rate was increased in some phonation methods. But their differences were less significant than other groups. After laryngomicrosurgery, mean air flow rate and expiratory air pressure were decreased in both groups. CONCLUSION: The aerodynamic test using the airway interruption method is a noninvasive, easy to perform and reliable for evaluation of aerodynamic conditions at the glottis. This research finds that the interruption method is effective both in evaluation of the treatment and in postoperative assessments of the laryngeal disorder patients.

Objective Evaluation of Phonation in the Normal and Pathological States / 听力学及言语疾病杂志

Mean flow rate (MFR) ,vocal intensity (I) ,pitch frequency(P) ,pitch perturbation (PP) and vocal efficiency (I/F) were measured simutaneously during sustained phonation of the vowel [i] at wide range levels of intensities in 158 nor mal subjects and the same parameters were measured at moderate vocal intensity level in 136 patients with various kinds of laryngeal diseases. PP indicates the amount of irregular vibration of vocal folds and I/F represents efficient transition from MFR to acoustic energy. When phonation at different intensities ,MFR,P and I/F increase but PP decreases when I increases. At moderate intensity phonation, there are positive correlations between MFR and I,and between I and P but negative correlation between MFR and I/F,between I(male) and PP,and between P(fe-male) and PP.Most of the patients with laryngeal diseases showed higher MFR and PP but lower I/F than normal subjects.MFR, PP and I/F could be used as objective and quantitative parameters with I and P as reference parameters in assessing laryngeal function of phonation.