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Manometric evidence for a phonation-induced UES contractile reflex
Lilani Perera1, Mark Kern, Candy Hofmann
1Division of Gastroenterology and Hepatology, Froedtert Hospital/Medical College of Wisconsin Dysphagia Institute, 9200 W Wisconsin Ave., Milwaukee, WI 53226, USA.
Summary
Phonation significantly increases upper esophageal sphincter (UES) pressure, acting as a protective barrier against stomach contents entering the pharynx. This effect is stronger in males than females.
Area of Science:
- Gastroenterology
- Physiology
- Otolaryngology
Background:
- The protective mechanism preventing gastric reflux into the pharynx during intense vocalization, common in professional singers, remains unclear.
- A potential mechanism involves the upper esophageal sphincter (UES) contracting during phonation to enhance the pressure barrier.
Purpose of the Study:
- To investigate the effect of phonation on intraluminal pressures within the esophagus and its sphincters.
- To determine if phonation induces a reflex contraction of the UES and to compare its pressure increase with other gastrointestinal segments.
Main Methods:
- Seventeen healthy volunteers underwent concurrent high-resolution manometry and voice analysis, testing various vowel sounds.
- Upper esophageal sphincter (UES) manometry with a water-perfused sleeve device confirmed findings in six subjects.
- Concurrent videofluoroscopy with high-resolution manometry and voice recording in eight volunteers analyzed laryngeal movement.
Main Results:
- All tested phonation frequencies and intensities significantly increased UES pressure (UESP) compared to prephonation levels.
- The UESP increase was significantly greater than pressure changes in the distal esophagus, lower esophageal sphincter (LES), and stomach.
- Videofluoroscopy showed no posterior laryngeal movement, ruling out a purely mechanical cause for the UES pressure increase.
- Phonation-induced UESP increases were significantly greater in males than in females.
Conclusions:
- Phonation induces a significant increase in UES pressure, suggesting a phonation-induced UES contractile reflex.
- This reflex provides a substantial pressure barrier, exceeding that of the distal esophagus, LES, and stomach.
- The magnitude of the phonation-induced UES pressure increase is influenced by sex.
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