Coghe J, Votion D, Lekeux P
Department of Physiology, Faculty of Veterinary Medicine, University of Liege, Belgium.
Vet J. 2000 Jul;160(1):25-32. doi: 10.1053/tvjl.2000.0464.
The use of lung scintigraphy in calves necessitates the validation of a ventilation (V) imaging agent compatible with clinical applications. This study aimed at defining the value of an inhaled radioactive aerosol (99mTc-DTPA) and a 'pseudogas' (Technegas) in the assessment of regional V in healthy conscious calves by comparing 99mTc-DTPA and Technegas deposition (D) images to V(V) images obtained from the steady-state inhalation of the short half-life krypton 81 (81mKr) gas. Images were compared by analysis of radioactivity distribution in computer-generated regions of interest within the right lung and D to V ratio images were generated in order to highlight areas of mismatching between 99mTc-DTPA or Technegas and 81mKr distributions. Results of this analysis showed that the 99mTc-DTPA aerosol droplets were unable to reach the lung parenchyma because of significant particle impaction in the major conducting airways. Better definition of the ventilated lung was obtained when using Technegas because of minimal deposition in conducting airways. Furthermore, the Technegas and 81mKr distribution patterns were highly equivalent.
在犊牛中使用肺闪烁扫描需要验证一种与临床应用兼容的通气（V）成像剂。本研究旨在通过将99mTc-DTPA和锝气体（Technegas）沉积（D）图像与从吸入短半衰期氪81（81mKr）气体的稳态吸入获得的V（V）图像进行比较，来确定吸入放射性气溶胶（99mTc-DTPA）和“假气体”（Technegas）在评估健康清醒犊牛区域V中的价值。通过分析右肺内计算机生成的感兴趣区域中的放射性分布来比较图像，并生成D与V比值图像，以突出99mTc-DTPA或Technegas与81mKr分布之间不匹配的区域。该分析结果表明，由于在主要传导气道中存在明显的颗粒撞击，99mTc-DTPA气溶胶滴无法到达肺实质。使用Technegas时，由于在传导气道中的沉积最少，因此对通气肺的定义更好。此外，Technegas和81mKr的分布模式高度等效。
