Neoglottic vibration in tracheoesophageal shunt phonation.

The purpose of the present study was to examine vibratory patterns of the neoglottis and to ascertain the neoglottic conditions that could cause failure in tracheoesophageal shunt phonation. We studied 30 tracheoesophageal shunt speakers while using "trap-door" type voice prostheses. Videostroboscopy was undertaken to investigate vibratory patterns of the neoglottis during phonation of the sustained vowel sound /e/ in these patients. The voice qualities of the patients were judged perceptually. A regular neoglottic vibration was observed in 21 patients. Nine patients had irregular neoglottic vibrations. In this latter group, two patients had incomplete neoglottic closures with breathy voices, four patients had multiple contacts of several mucosal walls with rough voices, and three patients had tight neoglottic closures with strained voices. During stroboscopic evaluation of tracheoesophageal shunt phonation, regularity of the neoglottic vibration may be the most significant finding. These findings show that it is as important to evaluate neoglottic vibration in alaryngeal voicing as it is to study glottic vibration in laryngeal voicing. Stroboscopic examination may be a help to elucidate a cause of failure in cases of poor tracheoesophageal shunt speech.