Pathophysiological study of neoglottis

本研究旨在探讨自体空肠移植行象鼻式发音重建术后的新声门和发音功能，并与食管发音或T-E分流术进行比较。用高速数字图像记录系统对新声门振动进行了研究。采用发音功能分析仪NAGASHIMA PS 77 E，同时测定发音时的呼气肺压、基频、声压级和平均流速（MFR）。食管入口上方的下咽粘膜起着食管发音的新声门的作用。新声门的粘膜表面像瓣膜一样突出并振动。在T-E分流的患者中，新声门闭合，发声时会振动。第二组接受了喉咽食管切除术，游离空肠移植：大象型分流。空肠腔内可见粘液膜振动。与食管发音不同，新声门在发声时保持开放。我们认为，当呼气通过分流管到达空肠腔时，局部粘膜受伯努利效应的吸引而成为声源，第一组呼气肺压和MFR均处于低或正常水平。大象式发音重建组的压力和MFR均处于较高水平。大象组的气道阻力（呼气肺压/MFR商）较高。由于发音重建部位的管腔狭窄且具有粘膜褶皱，因此呼气时气道阻力应该较高。换句话说，在大象组中，由于气管和新声门之间的气道狭窄，需要高呼气肺压。基于目前的结果，我们希望改进手术技术和训练方法，以更好地恢复声音。

This study was conducted to investigate the neoglottis and phonatory function after elephant type voice reconstruction using a free jejunal autograft in comparison with the patients of esophageal speech or T-E shunt. The neoglottic vibration was investigated using high-speed digital image recording System. Expiratory lung pressure during phonation was determined simultaneously with the fundamental frequency, sound pressure level, and mean flow rate (MFR), using the phonatory function analyzer NAGASHIMA PS77E.The first group underwent total laryngectomy. The hypopharyngeal mucosa above the esophageal entrance plays the role of the neoglottis of the esophageal speech. The mucosal surface of the neoglottis protrudes like a valve and vibrates. In the patient with a T-E shunt, the neoglottis is closed and vibrates during phonation.The second group underwent laryngopharyngoesophagectomy with a free jejunal graft : elephant type shunt. Mucosal vibration is seen in the lumen of the jejunum. In contrast to esophageal speech, the neoglottis remains open during phonation. We consider that when the expiratory air passes through the shunt to the jejunal lumen, the local mucosa is sucked by the Bernoulli effect to serve as a sound source.In the first group, both expiratory lung pressure and MFR were in low or normal level. In the elephant type voice reconstruction group, the pressure and MFR were in high level. The airway resistance, which is the expiratory lung pressure per MFR quotient, was high in the elephant group. Because the lumen of the voice reconstruction site is narrow and possesses mucosal folds, airway resistance should be high during expiration. In other words, a high expiratory lung pressure is required due to an airway stenosis between the trachea and neoglottis in the elephant group.Based on the present results, we wish to improve surgical techniques and training methods for better voice restoration.