HSC Section 6 Nov2016 Green Book

Reprinted by permission of J Voice. 2015; 29(6):755-762.

Vocal Fold Vibration in Vocal Fold Atrophy: Quantitative Analysis With High-Speed Digital Imaging

* Akihito Yamauchi, † Hisayuki Yokonishi, * Hiroshi Imagawa, ‡ Ken-Ichi Sakakibara, * Takaharu Nito, § Niro Tayama, and * Tatsuya Yamasoba, * yx Tokyo and z Hokkaido, Japan Summary: Introduction. Vocal fold vibrations of vocal fold atrophy (VFA), a rapidly increasing voice disorder owing to worldwide societal aging, have not been clarified by high-speed digital imaging (HSDI). Methods. The HSDI method was performed on 46 patients (33 males and 13 females) with VFA and 20 vocally healthy subjects (8 males and 12 females), and the obtained data were quantitatively evaluated by frame-by-frame anal- ysis, laryngotopography, single- and multi-line kymography, and glottal area waveform. Results. Overall, patients with VFA revealed larger open quotients, larger lateral phase difference, larger integral glottal width (the average glottal width over a glottal cycle), and smaller speed index than vocally healthy subjects. Some gender difference was noted: in males, lateral phase difference was not significant; and in females, integral glottal width and speed index were not significant. Correlation study revealed moderate correlations between HSDI-derived parameters and conventional acoustic or aerodynamic parameters. Conclusions. The combination of multiple HSDI analysis methods was effective in documenting the characteristics of vocal fold vibrations in VFA. The knowledge of general vibratory characteristics and gender difference is beneficial for the appropriate clinical care of VFA. Key Words: Vocal fold atrophy–Presbyphonia–High-speed digital imaging–Aging–Anti-aging.

provides reconstructed, averaged, illusory images. Second, HSDI offers wider application to clinical cases than videostroboscopy because HSDI is free from the problem with synchronization and is applicable to severe dysphonia in which videostroboscopy results in desynchronization. Third, various analysis methods for HSDI are now available, and thus HSDI provides more multifaceted information than videostroboscopy that has relatively limited choices of analysis methods. Furthermore, only little is known about the association between vibratory parameters and acoustic or aerodynamic parameters in VFA, 5 and HSDI data have not been reported on this matter. The connection between HSDI pa- rameters and routinely evaluated vocal function parameters in VFA should be beneficial for better understanding the patho- physiological aspects of this clinical entity. Hence, the purpose of the present study was to quantitatively elucidate the vibratory characteristics in VFA patients using HSDI, and to clarify the relationship between HSDI parameters and aerodynamic/acoustic measures. Patients who visited the Voice Outpatient Clinic of the Depart- ment of Otolaryngology and Head and Neck Surgery at the Uni- versity of Tokyo Hospital (Tokyo, Japan) and those who were diagnosed with VFA between 2006 and 2013 were included in this study. The diagnosis of VFA was based on careful history taking, acoustic and aerodynamic evaluation, and laryngostro- boscopic findings: Patients with objective dysphonia on acoustic or aerodynamic studies; without signs of other laryngeal dis- eases such as vocal fold paralysis, vocal fold polyp, laryngeal carcinoma, vocal fold scar, or functional dysphonia; and with the prominent vocal process, bowed vocal fold, spindle-shaped or anterior glottal gap, or increased open phase during phonation MATERIALS AND METHODS Subjects

INTRODUCTION Vocal fold atrophy (VFA) is a voice disorder resulting from the atrophiedmuscle andmucosa in the vocal folds. 1 These structural modifications lead to increased glottal air leakage and breathy, rough voice. Aging is considered to be the most major predispos- ing factor for VFA, although other risk factors have also been pro- posed (eg, reflux laryngitis, chronic medical conditions, and vocal abuse). 2 The VFA has increased considerably during the past two decades as a result of the worldwide societal aging, and thus, is attracting clinical attention in the world these days. 3,4 Laryngoscopically, the vocal fold bowing, prominent vocal process, and spindle-shaped glottal gap are usually observed. 1,2 The vibratory characteristics observed with videostroboscopy include normal or decreased amplitude, either complete closure or glottal gap, normal mucosal wave, and small supraglottal area. 1,2,5,6 The details of vocal fold vibrations in VFA, however, have not yet been documented by high-speed digital imaging (HSDI), although HSDI is considered to be the better choice than videostroboscopy. 7,8 First, HSDI is capable of observing actual vocal fold vibrations with a high frame rate, and guarantees reliable assessment of intra- and intercycle vibratory behaviors, unlike videostroboscopy that only From the *Department of Otolaryngology, The University of Tokyo Hospital, Tokyo, Japan; y Department of Otolaryngology, The Tokyo Metropolitan Police Hospital, Tokyo, Japan; z Department of Communication Disorders, The Health Sciences University of Hokkaido, Hokkaido, Japan; and the x Department of Otolaryngology and Tracheo- Esophagology, The National Center for Global Health and Medicine, Tokyo, Japan. Address correspondence and reprint requests to Akihito Yamauchi, Department of Otolaryngology, The University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655 Japan. E-mail: drachilles23@yahoo.co.jp Journal of Voice, Vol. - , No. - , pp. 1-8 0892-1997/$36.00 2015 The Voice Foundation http://dx.doi.org/10.1016/j.jvoice.2014.12.008 Accepted for publication December 15, 2014. This research was presented in the Seventh East Asian Conference on Phonosurgery; November 26–27, 2010; Tokyo, Japan.

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