Abstract
Rationale: The simultaneous measurement of regional lung ventilation, aerosol deposition and the anatomic configuration of airways are crucial for the better understanding of the determinants of aerosol deposition heterogeneity. However, no single imaging modality currently allows the acquisition of all such data simultaneously. The goal of this study was to test the feasibility of KES imaging to this end.
Methods: We used KES synchrotron radiation imaging [AJRCCM, 2009;180:296–303] to quantify regional lung ventilation, and the deposition of iodine (Iomeprol 88 mg/ml in NaCl 0.9%), delivered using an ultrasonic nebulizer (mass median aerodynamic diameter: 2.6±0.1 μm), in a healthy anesthetized, and mechanically ventilated rabbit (2.8 kg) in upright position. Regional ventilation images were obtained in 4 axial slices during inhalation of 70% Xe in O2. Regional iodine deposition images were obtained in 45 contiguous slices after 0, 5, 10, 15 and 20 minutes of nebulization.
Results: See figure. Aerosol deposition showed significant spatial heterogeneity in normal lung. Inset: 3D rendering of central conducting airways (dark) and iodine (medium) and parenchyma (light grey).
Conclusions: These data demonstrate the feasibility of K-edge subtraction imaging for the quantitative measurement of regional aerosol deposition, lung ventilation and airway morphology in vivo.
- © 2011 ERS
