Barrau Nathalie, Duwat Adrien, Fetita Catalin, Sambourg Killian, Beurnier Antoine, Pellot-Barakat Claire, Nemeth Angéline, Fernandez Brice, Boucneau Tanguy, Lebon Vincent, Maître Xavier
Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Orsay, France.
Institut National des Télécommunications, ARTEMIS, Evry, France.
Eur Radiol. 2025 Aug 8. doi: 10.1007/s00330-025-11838-0.
Functional pulmonary MRI can assess the pathophysiology of regional ventilation, provided that nominal ventilatory patterns are characterised as a baseline. This study investigates common features and their associated gravity dependence using 3D MR spirometry in freely breathing healthy volunteers.
Repeated dynamic lung MR acquisitions were performed at 3 T on 25 healthy volunteers breathing freely in the supine and prone positions. Three-dimensional maps of tidal volumes (TV), peak expiratory flows (SPEF), expiratory flows at 25% of tidal volume (SEF25), and anisotropy deformation index (ADI) were inferred and normalised. Intra- and inter-volunteer reproducibility was evaluated using percentage differences (PD) and intraclass correlation coefficients (ICC), while gravity dependence was tested using a paired Wilcoxon test.
Twenty-five volunteers (mean age, 45 years ± 17 [standard deviation]; 15 males) were included. Respiratory parametric maps are found spatially inhomogeneous throughout each volunteer's lung, with large coefficients of variation ranging between 30 and 63%. Yet, the main respiratory patterns are shared among volunteers with common features primarily governed by lung gravity dependence for TV, SPEF, and SEF25 (p < 0.05). Spirometry biomarkers are globally repeatable despite intrinsic physiological variabilities (median PD: 5.7-9.2%, ICC: 0.71-0.88), and fairly repeatable locally after normalisations (median PD: 11-19%, ICC: 0.78-0.90).
3D MR spirometry exhibits shared respiratory features between individuals with gravity dependence. Intra-volunteer repeatability and global accuracy were found, demonstrating the reliability of the technique. A new baseline is established for regional lung pathophysiology.
Question Nominal ventilatory patterns in free breathing need to be characterised for regional pathophysiology. Findings Functional ventilatory maps showed significant inhomogeneity, but key patterns, primarily governed by gravity, were consistent across subjects. 3D MR spirometry demonstrated reliability despite physiological variability. Clinical relevance 3D MR spirometry is a reliable technique for absolute quantification of the regional ventilation and its dynamic. Nominal spatial patterns of the ventilation should be considered for assessing regional pathophysiology in free breathing.
功能性肺部磁共振成像（MRI）能够评估局部通气的病理生理学情况，前提是将名义通气模式作为基线特征进行描述。本研究利用三维磁共振肺功能测定法，对自由呼吸的健康志愿者进行研究，以探究其共同特征及其与重力依赖性的关系。
在3T磁场下，对25名健康志愿者进行重复的动态肺部MRI采集，这些志愿者分别在仰卧位和俯卧位自由呼吸。推断并标准化潮气量（TV）、呼气峰值流速（SPEF）、潮气量25%时的呼气流量（SEF25）以及各向异性变形指数（ADI）的三维图谱。使用百分比差异（PD）和组内相关系数（ICC）评估志愿者内部和志愿者之间的可重复性，同时使用配对威尔科克森检验测试重力依赖性。
纳入了25名志愿者（平均年龄45岁±17[标准差]；15名男性）。在每位志愿者的整个肺部中，呼吸参数图谱在空间上是不均匀的，变异系数较大，范围在30%至63%之间。然而，主要的呼吸模式在志愿者之间是共有的，其共同特征主要由TV、SPEF和SEF25的肺部重力依赖性决定（p<0.05）。尽管存在内在的生理变异性，但肺功能测定生物标志物在整体上是可重复的（中位PD：5.7 - 9.2%，ICC：0.71 - 0.88），在标准化后局部也具有相当的可重复性（中位PD：11 - 19%，ICC：0.78 - 0.90）。
三维磁共振肺功能测定法显示个体之间存在具有重力依赖性的共同呼吸特征。发现了志愿者内部的可重复性和整体准确性，证明了该技术的可靠性。为局部肺部病理生理学建立了一个新的基线。
问题：对于局部病理生理学，需要描述自由呼吸时的名义通气模式。发现：功能性通气图谱显示出显著的不均匀性，但主要由重力决定的关键模式在各受试者之间是一致的。尽管存在生理变异性，三维磁共振肺功能测定法仍显示出可靠性。临床意义：三维磁共振肺功能测定法是一种用于绝对量化局部通气及其动态变化的可靠技术。在评估自由呼吸时的局部病理生理学时，应考虑通气的名义空间模式。
