Niro Tayama

Role of Laryngeal Movement and Effect of Aging on Swallowing Pressure in the Pharynx and Upper Esophageal Sphincter

Objectives Describe contribution of laryngeal movement to pressure changes at the upper esophageal sphincter (UES) and the effect of aging on the swallowing function.

High-speed digital imaging of the medial surface of the vocal folds

High-speed digital imaging of the medial surface of the vocal folds was performed in excised canine larynx experiments. Building on the excised larynx investigations of Baer [Ph.D. dissertation, MIT, Boston, MA (1975)] and hemilarynx investigations of Jiang and Titze [Laryngoscope 103, 872-882 (1993)], nine vocal fold fleshpoints were tracked simultaneously along the medial surface of one coronal plane of the left vocal fold using a Kodak EktaPro 4540 high-speed digital imaging system. By imaging from two distinct views, 3D reconstructions of fleshpoint trajectories were performed with a sampling frequency of 4.5 kHz and a spatial resolution of approximately 0.08 mm. Quantitative results were derived from a typical example of periodic chestlike vibrations. Furthermore, these data were decomposed into empirical eigenfunctions, the building blocks of vocal fold vibration, illuminating basic mechanisms of self-sustained oscillation. Previously, such mechanisms have only been explored theoretically using computer models of vocal fold vibration [Berry et al., J. Acoust. Soc. Am. 95, 3595-3604 (1994)]. Similar to the theoretical studies, two eigenfunctions captured 98% of the variance of the data. Because this investigation utilized high-speed technology, the methodology may also be used to examine complex, aperiodic vibrations. Thus, this technique allows mechanisms of regular and irregular vocal fold vibration to be explored using direct observations of vibrating tissues in the laboratory.

Surgical management of the plunging ranula : a review of seven cases

We have treated seven patients with a plunging ranula during the past 10 years. All patients underwent surgery via a cervical approach. In two, the ranula reached the anterior neck by passing through a dehiscence in the mylohyoid muscle, while in the other five the plunging ranula passed posteriorly to the mylohyoid muscle. A pseudocyst was extirpated in each patient. Although total sublingual gland excision was not performed in two patients, no recurrence was observed in any patient. Incision of the pseudocyst facilitated subsequent procedures and decreased the incidence of transient facial paralysis. In the presence of a cervical mass without swelling of the oral floor, a cervical approach may still be the method of choice either for the first operation or for salvage surgery after recurrence subsequent to intraoral procedures. It is based on the fact that there may be ectopic sublingual glands residing on the inferior surface of the mylohyoid muscle.

Clinical analysis of presbylarynx—Vocal fold atrophy in elderly individuals

OBJECTIVE The proportion of elderly Japanese is increasing significantly and aging society greatly influences the medical services. The number of elderly patients who visited out Voice Outpatient Clinic has been increasing in recent years. The aim of the present study was to analyze the trend in the number of patients with aging-related vocal fold atrophy, and to assess the characteristics of senile change of vocal function. METHODS A retrospective review of the 1999-2005 medical records of patients aged > or =65 years was conducted, and patients with presbylarynx were analyzed. We evaluated age, sex, occupation, maximal phonation time (MPT), and mean airflow rate (MFR) during comfortable phonation to assess the physiological characteristics of senile change of vocal function. We compared MFR of presbylarynx with those of normal elderly person. RESULTS The number of patients aged > or =65 who visited our clinic in the 7-year study period was 361, and 72 (20%) were diagnosed with vocal fold atrophy. They included 47 (65%) men and 25 (35%) women, with a mean age of 71 years (range, 65-89). Among these patients, 27 (38%) were still employed at the time of consultation, while 17 (24%) were retired, at least 26 jobs required voice skills; and 15 patients (21%) were involved in singing and recitation of poems. MPT correlated negatively with age, while MFR correlated positively with age. CONCLUSION The number of elderly patient with vocal fold atrophy increased gradually almost every year. The male patients account for 65%. Thirty-three percent of patient of the present study with presbylarynx were still in the workforce. MFR correlated positively and significantly with age. MFR was higher in presbylarynx than normal elderly person.

Evaluation of Vocal Fold Vibration With an Assessment Form for High-Speed Digital Imaging: Comparative Study between Healthy Young and Elderly Subjects

OBJECTIVES/STUDY DESIGN We conducted a prospective study with a subjective assessment form for high-speed digital imaging (HSDI) to elucidate the features of vocal fold vibrations in vocally healthy subjects and to clarify gender- and age-related differences. METHODS Healthy adult volunteers participated in this study. They were divided into young (aged 35 and younger) and elderly (aged 65 and older) groups, and the scores of an assessment form for HSDI characteristics elaborated at our institution were statistically analyzed. RESULTS Twenty-six young subjects (males: 9, females: 17; mean age: 27 years) and 20 elderly subjects (males: 8, females: 12; mean age: 72 years) were assigned to our study. Posterior gap and posterior-to-anterior longitudinal phase difference were characteristic to young females, whereas in young males, mucosal wave, anterior-to-posterior longitudinal phase difference, and supraglottic hyperactivity were frequent. In elderly males, axis shift, asymmetry, supraglottic hyperactivity, increased mucosal wave, lateral phase difference, and anterior-to-posterior longitudinal phase difference were frequent; and in elderly females, high incidence of lateral phase difference, atrophic change, anterior gap, and asymmetry were observed. CONCLUSIONS The results show that the behaviors of vocal fold vibrations were diverse even in healthy subjects with no vocal complaints or history of laryngeal diseases, and hence, the diversity of vocal fold vibrations in normal subjects must be taken into account in evaluating vocal fold vibrations.

Aerodynamic Profiles of a Hemilarynx with a Vocal Tract

The pressure-flow relationship was examined in excised canine and human larynges with and without a vocal tract. Canine and human larynges were prepared and cut in the midsagittal plane from the top to about 10 mm below the vocal folds. The right half was removed and replaced with an acrylic plate. The vocal tract was simulated initially with a 15-cm plastic tube and later with a vocal tract model with an area function resembling “ah.” Simultaneous recordings were made of the glottal pressure, mean subglottal pressure, and average airflow at various levels of adduction. Preliminary data indicated that the pressure-flow relationships were similar to those of a full larynx and were almost linear. The addition of the vocal tract increased the glottal resistance by moving these pressure-flow lines to the lower-flow and higher-pressure region. The human larynx appears to phonate more easily than the canine larynx on the laboratory bench and has lower phonation threshold pressures.

Single institutional analysis of trends over 45 years in etiology of vocal fold paralysis

OBJECTIVE It is important to assess the causes of vocal fold paralysis. Many studies have reported causes of paralysis, but few reports have shown changes in longitudinal etiology in a single institution. METHODS We investigated the medical records of 797 patients with vocal fold paralysis from 1990 to 2005 at the voice and bronchoesophageal outpatient clinics at the University of Tokyo Hospital. We evaluated the etiology of paralysis, and compared our results with a previous study by Hirose in our clinic from 1961 to 1989 to assess changes in etiology. RESULTS The postoperative group comprised 466 patients (58.5%), while the non-surgical group comprised 331 (41.5%) patients. In the postoperative group, the most common cause of paralysis was thyroid surgery (106 cases), and other common causes were surgery for aortic aneurysm (61 cases) and tracheal intubation (58 cases). In the non-surgical group, idiopathic paralysis (134 cases) was the most common cause. Other common causes were lung cancer (34 cases) and cerebrovascular disease (24 cases). In a previous study from our clinic, the rate of postoperative paralysis was 43.5%. In the current analysis, the percentage of postoperative patients has increased remarkably compared with that of the previous report while the rate of idiopathic paralysis, has decreased by half. CONCLUSION The increase in postoperative cases of paralysis may be caused by the increasing frequency of operations for many diseases, due to the progress of medical techniques in recent years. The decrease in idiopathic cases may be related to the advances of diagnostic devices such as CT and MRI.

Videofluoroscopic assessment of swallowing function in patients with myasthenia gravis.

Swallowing function in myasthenia gravis (MG) was investigated by videofluoroscopy (VF). A total of 23 VF examinations were performed on 11 MG patients at various time points over the exacerbation and remission stages of disease. The assessment parameters on VF examination are set as follows: bolus transport from the mouth to the pharynx, bolus holding in the oral cavity, velopharyngeal seal, tongue base movement, pharyngeal constriction, laryngeal elevation, upper esophageal sphincter (UES) opening, and bolus stasis at the pyriform sinus (PS). Aspiration was also assessed on VF examination. Aspiration was seen in 34.8%, and half of these cases involved silent aspiration. Three of four cases that showed silent aspiration went on to experience aspiration pneumonia during the follow-up term. By Spearmans rank correlation, disturbance of laryngeal elevation was significantly correlated with aspiration (p=0.001), and incomplete UES opening was not significantly, but tended to be, correlated with aspiration (p=0.067). Although other parameters in the oral and pharyngeal phase on VF examination, such as bolus transport from the oral cavity to the pharynx, pharyngeal constriction, or stasis at the PS, were remarkably disturbed (in more than 50% of the examinations), those parameters were not good indicators for aspiration. When a disturbance of laryngeal elevation is found at a bedside clinical test, we recommend performing precise swallowing evaluation, such as VF, Fiberoptic Endoscopic Evaluation of Swallowing (FEES), and/or scintigraphic assessment of swallowing, for MG patients, to detect silent aspiration.

Diagnosis and Physiopathology of Laryngeal Deposits in Autoimmune Disease

We report the clinical features and pathology of a previously unreported form of vocal fold disease seen in 4 patients, 3 of whom were diagnosed as autoimmune disease. The characteristic features of these lesions were found as bilateral transverse lesions in the mid portion of the vocal folds. The patients had dysphonia and diplophonia. Stroboscopic examinations showed 180-degree phase shifts between the anterior and posterior portion of the vocal folds. Case 1 had systemic lupus erythematosus, case 2 had Hashimoto’s thyroiditis, and case 3 had progressive systemic sclerosis. Prior to the onset of hoarseness, autoimmune antibody titers were increased. These cases need differential diagnosis from vocal fold nodules and cysts. Two cases were recurrent after endoscopic surgery, 1 recurring 3 times. Glucocorticoid was effective in preventing the recurrence in the early phase. Recurrence may have occurred because the surgical strategy was the same as that used for vocal fold nodules or cysts.

Arytenoid Adduction for Correcting Vocal Fold Asymmetry: High-Speed Imaging

Objectives We hypothesized that high-speed digital imaging provides a quantitative method to evaluate the effect of arytenoid adduction for the correction of asymmetric and irregular vocal fold vibration in unilateral vocal fold paralysis. Methods Six subjects with unilateral vocal fold paralysis participated in the study (4 male, 2 female; mean [±SD] age, 52.5 ± 21.3 years). Videokymographic and laryngotopographic methods for image analysis were performed for highspeed recordings of vocal fold vibration for visualizing the glottal vibratory patterns, and for quantifying the frequency of vibration of each vocal fold, respectively. Comparisons of the paralyzed and the normal vocal folds were made before and after arytenoid adduction. Results Analysis of the laryngotopographs revealed 2 distinct frequencies of vibration for the paralyzed and the contralateral vocal folds for all subjects before surgery. After arytenoid adduction, the vibration frequencies became identical or nearly identical in all subjects. Conclusions Asymmetric vibration in vocal fold paralysis was exemplified by differences in vibration frequency between the vocal folds. The present data showed that after arytenoid adduction the vibration frequencies and the vibratory patterns of the contralateral vocal folds approached symmetry. This surgical procedure could improve the functional symmetry of the larynx for phonation.