Stroboscopy
Laryngology 101: Laryngoscopy the art of seeing the voice (vocal cords) (Article)
Laryngoscopy is the art of placing a camera in the throat to view the vocal cords. Important aspects of how to perform the examination, what structures can be seen and how do different areas function are described. A laryngoscopy is the foundation for diagnosing hoarseness or voice problems. (posted 8:27 PM, February 9, 2015)
normal larynx video without and with stroboscopy (Article)
This video shows the larynx of a college-age singer with a healthy larynx. The vibration is seen as a blur at first, but halfway through, the halogen light is turned off and the strobe (xenon) light is turned on. The stroboscopy gives the optimal illusion of slow-motion vibration, allowing us to see the mucosal wave. Notice the symmetry and regularity of the normal mucosal wave. (posted 2:34 PM, August 27, 2014)
left paresis pre-surgery stroboscopy video (Article)
This video is one of four in a series showing the larynx of an adult female with a left vocal fold paresis (incomplete paralysis). Note that the left vocal fold does move slightly, but is very limited compared to the right. The paresis results in weak glottic closure, which prevents normal vocal fold vibration. This video shows the larynx prior to a thyroplasty, that is, surgical placement of an implant that provides improved glottic closure and therefore better vibration. This series of videos provides a good demonstration of the concept of entrainment, in which the vocal folds become "entrained" in the airstream to vibrate, as long as they are close enough together, and have similar underlying muscle tone. The stroboscopy makes it clear that entrainment is often not achieved, leaving the vocal folds to vibrate separately, often at different frequencies. When the pitch is high enough, and there is enough longitudinal tension along the left vocal fold, the right vocal fold can vibrate against it with adequate regularity to a achieve a stable frequency, although the glottic closure is insufficient for much volume. (posted 2:34 PM, August 27, 2014)
left paresis post-surgery stroboscopy video (Article)
This video is one of four in a series showing the larynx of an adult female with a left vocal fold paresis (incomplete paralysis). Note that the left vocal fold does move slightly, but is very limited compared to the right. The paresis results in weak glottic closure, which prevents normal vocal fold vibration. This video shows the larynx after thyroplasty, that is, surgical placement of an implant that provides improved glottic closure and therefore better vibration. This series of videos provides a good demonstration of the concept of entrainment, in which the vocal folds become "entrained" in the airstream to vibrate, as long as they are close enough together, and have similar underlying muscle tone. The improvement in entrainment provided by the improved glottic closure allows for much more normal vibration of the vocal folds. (posted 2:34 PM, August 27, 2014)
How to Find a Voice Doctor (Article)
The purpose of the article is to help the individual, teacher, and family member navigate through the vocal health care system. The different types of voice care professionals involved in voice evaluation and treatment are mentioned. A variety of key components of voice evaluation are described as well as assists in providing the reader with a method to find a voice care physician. (posted 2:34 PM, August 27, 2014)