Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio.
J Appl Physiol (1985). 2021 Nov 1;131(5):1629-1639. doi: 10.1152/japplphysiol.00694.2020. Epub 2021 Sep 16.
Surgical treatment of obstructive sleep apnea (OSA) in children requires knowledge of upper airway dynamics, including the closing pressure (Pcrit), a measure of airway collapsibility. We applied a flow-structure interaction (FSI) computational model to estimate Pcrit in patient-specific upper airway models obtained from magnetic resonance imaging (MRI) scans. We sought to examine the agreement between measured and estimated Pcrit from FSI models in children with Down syndrome. We hypothesized that the estimated Pcrit would accurately reflect measured Pcrit during sleep and therefore reflect the severity of OSA as measured by the obstructive apnea-hypopnea index (AHI). All participants ( = 41) underwent polysomnography and sedated sleep MRI scans. We used Bland-Altman plots to examine the agreement between measured and estimated Pcrit. We determined associations between estimated Pcrit and OSA severity, as measured by AHI, using regression models. The agreement between passive and estimated Pcrit showed a fixed bias of -1.31 [confidence interval (CI) = -2.78, 0.15] and a nonsignificant proportional bias. A weaker agreement with active Pcrit was observed. A model including AHI, gender, an interaction term for AHI, and gender and neck circumference explained the largest variation ( = 0.61) in the relationship between AHI and estimated Pcrit ( < 0.0001). Overlap between the areas of the airway with the lowest stiffness, and areas of collapse on dynamic MRI, was 77.4 ± 30% for the nasopharyngeal region and 78.6 ± 33% for the retroglossal region. The agreement between measured and estimated Pcrit and the significant association with AHI supports the validity of Pcrit estimates from the FSI model. We present a noninvasive method for estimating critical closing pressure (Pcrit) using fluid-structure interaction (FSI) simulations and magnetic resonance imaging (MRI) scans in patients with obstructive sleep apnea (OSA). We used patient-specific stiffness measures in our FSI model to account for any individual variability in the elasticity of soft tissues surrounding the upper airway. We validated this model by measuring the degree of agreement between measured and estimated Pcrit.
小儿阻塞性睡眠呼吸暂停（OSA）的手术治疗需要了解上呼吸道动力学，包括气道关闭压（Pcrit），这是气道塌陷程度的一个衡量标准。我们应用流固耦合（FSI）计算模型来估计从磁共振成像（MRI）扫描获得的患者特定的上气道模型中的 Pcrit。我们旨在检查 FSI 模型中测量的和估计的 Pcrit 在唐氏综合征患儿中的一致性。我们假设估计的 Pcrit 将在睡眠期间准确反映测量的 Pcrit，因此反映阻塞性呼吸暂停低通气指数（AHI）所测量的 OSA 的严重程度。所有参与者（n=41）都接受了多导睡眠图和镇静睡眠 MRI 扫描。我们使用 Bland-Altman 图来检查测量的和估计的 Pcrit 之间的一致性。我们使用回归模型确定估计的 Pcrit 与 OSA 严重程度（由 AHI 衡量）之间的关联。被动和估计的 Pcrit 之间的一致性显示出固定的偏差为-1.31（置信区间（CI）=-2.78，0.15），并且没有显著的比例偏差。与主动 Pcrit 的一致性较差。包括 AHI、性别、AHI 的性别交互项以及颈围的模型解释了 AHI 和估计的 Pcrit 之间关系的最大变化（R²=0.61）（<0.0001）。气道中刚度最低的区域和动态 MRI 上塌陷区域之间的重叠度，在鼻咽区域为 77.4±30%，在舌后区为 78.6±33%。测量的和估计的 Pcrit 之间的一致性以及与 AHI 的显著关联支持 FSI 模型中 Pcrit 估计的有效性。我们提出了一种使用流体-结构相互作用（FSI）模拟和磁共振成像（MRI）扫描来估计阻塞性睡眠呼吸暂停（OSA）患者临界关闭压力（Pcrit）的非侵入性方法。我们在 FSI 模型中使用了患者特定的刚度测量值，以考虑上气道周围软组织弹性的任何个体差异。我们通过测量测量的和估计的 Pcrit 之间的一致性程度来验证该模型。
