Baggott Christopher D, Yuen Alexander K, Hoffman Matthew R, Zhou Liang, Jiang Jack J
Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792-7375, USA.
Laryngoscope. 2007 Aug;117(8):1491-5. doi: 10.1097/mlg.0b013e318063e89e.
Subglottal pressure (SGP) is a valuable parameter in the research and clinical assessment of laryngeal function. The lungs serve as a constant pressure source during sustained phonation, and that pressure, SGP, can be used to determine the efficiency with which the larynx converts aerodynamic power to acoustic power. As the larynx serves as an aerodynamic transducer, the vocal efficiency (Ve) coefficient, defined as acoustic power (dB) divided by aerodynamic power (SGP x glottal airflow) has been shown to reliably reflect vocal health. However, current SGP measurement techniques are hesitantly used because of either an invasive nature or the requirement of intensive patient training. This study tests a novel device that has been designed to noninvasively estimate SGP through mechanical airflow redirection, producing a numeric output on completion of the trial, which lasts only a few seconds. The novelty of this design lies in the ease of use for both the patient and the clinician. Multiple mechanical airflow redirections occlude the airway for only 135 ms, which is predicted to limit the effect of confounding laryngeal reflexes that may occur during the trials. Additionally, the airflow redirection into a retention device allows for the pneumatic in-trial comparison of the estimated SGP with the pressure achieved by the patient, providing a numeric output to the clinician on completion.
声门下压力（SGP）是喉部功能研究和临床评估中的一个重要参数。在持续发声过程中，肺部作为一个恒定的压力源，而该压力即SGP，可用于确定喉部将气动功率转换为声功率的效率。由于喉部是一个气动换能器，已证明定义为声功率（dB）除以气动功率（SGP×声门气流）的发声效率（Ve）系数能够可靠地反映发声健康状况。然而，由于当前SGP测量技术具有侵入性或需要患者进行密集训练，因此使用时较为谨慎。本研究测试了一种新型设备，该设备旨在通过机械气流重定向来无创估计SGP，在试验完成时产生一个数字输出，整个试验仅持续几秒钟。这种设计的新颖之处在于对患者和临床医生来说都易于使用。多次机械气流重定向使气道阻塞仅持续135毫秒，预计这将限制试验期间可能出现的混淆喉反射的影响。此外，气流重定向到一个保留装置中，允许在试验过程中对估计的SGP与患者实现的压力进行气动比较，并在完成时向临床医生提供一个数字输出。
