Abstract
During the past 17 years we have been performing the tracheoesophageal (TE) fistulization for voice reconstruction following total laryngectomy. The principle of this technique is to divert the exhaled air through the TE fistula into the esophagus and vibrate hypopharyngeal mucosa. Radiographical examination and manometry during TE phonation reveal that the thyropharyngeal muscle forms the retropharyngeal prominence on which the neoglottis is located. It has been alreadly reported that the glottis is open for voiceless sounds with laryngeal articulatory adjustment in laryngeal speech. Although TE speakers have lost the larynx, they produce voiceless and voiced sounds with articulatory adjustment. This strongly suggests that neoglottic adjustment exists in TE speech. This study was designed to clarify its mechanism.
Ten speakers were subjected to this study consisting of the fiberoptic examination of the neoglottis, and aerodynamic and electromyographic (EMG) studies with the test words of voiceless or voiced plosives.
Fiberoptic examination revealed a transient neoglottal opening for voiceless sound production. The EMG activity of the thyropharyngeal muscle decreased for voiceless sound production. The EMG activity reduction started prior to the increase of the supraneoglottal pressure. These findings indicate that the neoglottic adjustment plays an important role to open the neoglottis in TE speech.
