The Vertical Level of the Paralyzed Vocal Fold in Unilateral Vocal Fold Paralysis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: ln the unilateral vocal fold paralysis, it has been generally accepted that the level of the paralyzed vocal fold is higher than that of a normally innervated vocal fold. In this study, we introduce methods to detect the level difference between the paralyzed and innervated vocal folds, and observe the vertical levels of paralyzed vocal fold. MATERIALS AND METHOD: We conducted a retrospective review using video recorded images of the larynx. A total of 38 patients selected for this study complained of voice change due to a unilaterally paralyzed vocal fold. Video-recordings were obtained using a laryngeal telescope. The height was assessed according to the paralyzed positions, status (inspiration or phonation) and shapes of the paralyzed arytenoid. The shapes of paralyzed arytenoid during inspiration were classified as a body type, process type, tip type and no type. RESULTS: In the medial paralysis, a paralyzed vocal fold showed same horizontal level as does a normal vocal fold during phonation. But in some cases of medial paralysis, the vertical level was either lower or higher than the normal vocal fold depending on the types of paralyzed arytenoid during phonation. In the lateral paralysis, interestingly, most of the paralyzed vocal fold is not vertically higher than an innervated vocal fold during phonation. CONCLUSIONS: The height of paralyzed vocal fold depends on the paralyzed positions, inspiration or phonation, and shapes of the paralyzed atytenoid. The fact that a paralyzed vocal fold is placed vertically higher than a normal vocal fold should be reconsidered from now.

Acoustic and Electromyographic Characteristics of Fluent Alaryngeal Speech / 대한이비인후과학회지

Alaryngeal speech(esophageal, neoglottal, shunt, and electrolaryngeal speech) differ from normal laryngeal speech primarily with regard to the sound or source of voicing. Theoretically, esophageal, tracheoesophageal, neoglottal and electrolaryngeal speech have difficulty in accomplishing the voiceless consonants. But perceptual studies often reveal that there is a clear production of voiceless consonants resulting good articulation scores in skilled alaryngeal speakers except electrolaryngeal speech. The purpose of the present study was to relate the three-way distinction of Korean voiceless stops in manner of articulation with normal speakers and skilled alaryngeal speakers in terms of the voicing distinction in consonants. Acoustic analysis were performed to investigate the acoustic characteristics of alaryngeal speech compared to the normal speech with special reference to the voiceless distinction. Electromyographic studies were performed to clarify the adjustment of neck muscle during normal and alaryngeal speech.