Novel neuromechanical measurements of the human upper airway in health and disease

阻塞性睡眠呼吸暂停（OSA）是一种常见的疾病，其中上呼吸道在睡眠期间反复塌陷，导致血液中的氧气浓度下降，二氧化碳上升，并且人为了重新建立足够的氧气供应而觉醒。OSA的后果包括白天嗜睡增加，事故风险增加和心血管疾病风险增加。它最常见于中年男性，但也见于更广泛的人群。阻塞性睡眠呼吸暂停与肥胖和上呼吸道及面部结构的特定形状有关。这些解剖学因素可以在清醒时得到补偿，但睡眠期间上气道周围肌肉的活动不足会导致气道塌陷的倾向增加。当肌肉无法承受气道中的低压并塌陷，阻塞气道时，发生气道塌陷。该项目将测量健康人和OSA患者气道周围肌肉的刚度和运动，以确定这些肌肉如何影响气道可扩张性。我们将使用两种新的非侵入性磁共振成像（MRI）技术，MR弹性成像和MR标记，这将使我们能够量化气道刚度或弹性及其运动（变形）。这将是人类上呼吸道弹性和变形的首次直接测量。我们还将测量各种治疗，如CPAP治疗和下颌前移如何影响气道弹性和变形，以便更好地了解其机制。这也可以解释为什么有些患者不能从这些治疗中获益。这些研究可能会导致新的诊断和治疗方式，以及获得重要的见解，人类气道塌陷的基本机制。

Obstructive sleep apnea (OSA) is a common condition, in which the upper airway repeatedly collapses during sleep, causing the oxygen concentration in the blood to drop, carbon dioxide to rise, and the person to arouse in order to re-establish adequate oxygen supply. Consequences of OSA include increased daytime sleepiness, increased risk of accidents, and increased risk of cardiovascular diseases. It most commonly affects middle-aged males, but is also seen in the broader population. OSA is associated with obesity and specific shapes of the upper airway and facial structure. These anatomical factors can be compensated for while awake but inadequate activity of the muscles surrounding the upper airway during sleep contributes to an increased predisposition of the airway to collapse. Airway collapse occurs when the muscles are unable to withstand the low pressures in the airway and collapse, obstructing the airway. This project will measure the stiffness and motion of the muscles surrounding the airway, in healthy people and those with OSA, to determine how these influence airway collapsibility. We will use two novel non-invasive Magnetic Resonance Imaging (MRI) techniques, MR Elastography, and MR tagging which will allow us to quantify the airway stiffness, or elasticity, and its motion (deformation). These will be the first direct measurements of the upper airway elasticity and deformation in humans. We will also measure how various treatments, such as CPAP therapy and mandibular advancement affect airway elasticity and deformation, so that their mechanisms can be better understood. This may also explain why some patients do not benefit from these therapies. These studies may lead to new diagnostic and treatment modalities, as well as gaining important insights into the basic mechanisms of airway collapse in humans.