Park Eun-Ah, Goo Jin Mo, Park Sang Joon, Lee Chang Hyun, Park Chang Min
Department of Radiology, Seoul National University College of Medicine and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 110-744, Korea.
Department of Radiology, Seoul National University College of Medicine and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 110-744, Korea. ; Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea.
Korean J Radiol. 2015 May-Jun;16(3):648-56. doi: 10.3348/kjr.2015.16.3.648. Epub 2015 May 13.
The aim of this study was to evaluate whether the difference in the degree of collateral ventilation between canine and swine models of bronchial obstruction could be detected by using xenon-enhanced dynamic dual-energy CT.
Eight mongrel dogs and six pigs underwent dynamic dual-energy scanning of 64-slice dual-source CT at 12-second interval for 2-minute wash-in period (60% xenon) and at 24-second interval for 3-minute wash-out period with segmental bronchus occluded. Ventilation parameters of magnitude (A value), maximal slope, velocity (K value), and time-to-peak (TTP) enhancement were calculated from dynamic xenon maps using exponential function of Kety model.
A larger difference in A value between parenchyma was observed in pigs than in dogs (absolute difference, -33.0 ± 5.0 Hounsfield units [HU] vs. -2.8 ± 7.1 HU, p = 0.001; normalized percentage difference, -79.8 ± 1.8% vs. -5.4 ± 16.4%, p = 0.0007). Mean maximal slopes in both periods in the occluded parenchyma only decreased in pigs (all p < 0.05). K values of both periods were not different (p = 0.892) in dogs. However, a significant (p = 0.027) difference was found in pigs in the wash-in period. TTP was delayed in the occluded parenchyma in pigs (p = 0.013) but not in dogs (p = 0.892).
Xenon-ventilation CT allows the quantification of collateral ventilation and detection of differences between canine and swine models of bronchial obstruction.
本研究旨在评估使用氙增强动态双能CT是否能够检测出犬类和猪类支气管阻塞模型之间侧支通气程度的差异。
八只杂种犬和六头猪接受了64层双源CT的动态双能扫描，在闭塞节段支气管的情况下，以12秒的间隔进行2分钟的灌注期（60%氙）动态扫描，然后以24秒的间隔进行3分钟的洗脱期扫描。使用凯蒂模型的指数函数从动态氙图中计算出通气参数，包括幅度（A值）、最大斜率、速度（K值）和峰值时间（TTP）增强。
观察到猪实质之间的A值差异比犬类更大（绝对差异，-33.0±5.0亨氏单位[HU]对-2.8±7.1 HU，p = 0.001；标准化百分比差异，-79.8±1.8%对-5.4±16.4%，p = 0.0007）。仅在猪的闭塞实质中，两个时期的平均最大斜率均降低（所有p<0.05）。犬类两个时期的K值无差异（p = 0.892）。然而，在猪的灌注期发现有显著差异（p = 0.027）。猪的闭塞实质中TTP延迟（p = 0.013），而犬类中未延迟（p = 0.892）。
氙通气CT能够对侧支通气进行定量分析，并检测出犬类和猪类支气管阻塞模型之间的差异。
