Reinhardt Joseph M, Ding Kai, Cao Kunlin, Christensen Gary E, Hoffman Eric A, Bodas Shalmali V
Department of Biomedical Engineering, University of Iowa, Iowa City, IA 52242, USA.
Med Image Anal. 2008 Dec;12(6):752-63. doi: 10.1016/j.media.2008.03.007. Epub 2008 Apr 12.
The main function of the respiratory system is gas exchange. Since many disease or injury conditions can cause biomechanical or material property changes that can alter lung function, there is a great interest in measuring regional lung ventilation and regional specific volume change. We describe a registration-based technique for estimating local lung expansion from multiple respiratory-gated CT images of the thorax. The degree of regional lung expansion is measured using the Jacobian (a function of local partial derivatives) of the registration displacement field, which we show is directly related to specific volume change. We compare the ventral-dorsal patterns of lung expansion estimated across five pressure changes to a xenon CT based measure of specific ventilation in five anesthetized sheep studied in the supine orientation. Using 3D image registration to match images acquired at 10 cm H(2)O and 15 cm H(2)O airway pressures gave the best match between the average Jacobian and the xenon CT specific ventilation (linear regression, average r(2)=0.73).
呼吸系统的主要功能是气体交换。由于许多疾病或损伤情况会导致生物力学或材料特性的变化，进而改变肺功能，因此人们对测量局部肺通气和局部比容变化有着浓厚的兴趣。我们描述了一种基于配准的技术，用于从胸部的多个呼吸门控CT图像估计局部肺扩张。使用配准位移场的雅可比行列式（局部偏导数的函数）来测量局部肺扩张程度，我们证明它与比容变化直接相关。我们将在仰卧位研究的五只麻醉绵羊中，在五个压力变化下估计的肺扩张腹背模式与基于氙CT的比通气量测量值进行了比较。使用三维图像配准来匹配在气道压力为10 cm H₂O和15 cm H₂O时采集的图像，平均雅可比行列式与氙CT比通气量之间的匹配度最佳（线性回归，平均r² = 0.73）。
