Correlation Between Lung CT Texture Features And Renal Perfusion After Rabbit Paraquat Poisoning

Objective:To investigate the correlation between lung CT texture features and renal CT perfusion parameters Renal blood flow(RBF)after multiple organ dysfunction induced by rabbit paraquat poisoning.Methods:Twenty-four rabbits were randomly divided into control group(normal saline)and paraquat(35 mg/kg)group.All groups underwent 320-row CT lung volume scan and renal perfusion imaging scan at 2 hours,24 hours,7 days and 14 days after drug gavage.The images of bilateral lung volume CT scan and double renal perfusion were obtained.The lung CT texture features of each group were extracted at each time point for texture analysis and the RBF values were measured on CT perfusion Pseudocolor maps.The correlation analysis between rabbit lung CT texture features and RBF was performed by Pearson correlation analysis.Meanwhile,two rabbits were randomly killed in each group,and the lung and renal tissues were dissected for pathological examination.Results:1.Renal and lung pathological changes:1)Observation under light microscope showed that the morphology and structure of kidney cortex and medulla were normal in the control group;the pathological changes of the kidney tissue in the paraquat group from 2 hours to 14 days included a small amount of eosinophilic substance in the renal capsule,renal tubular dilatation,cytoplasmic vacuolation of renal tubular epithelial cells,nuclear pyknosis hyperchromatic,renal tubular visible protein tube type,detached epithelial cells seen locally,renal capsule atrophy in the renal cortex,and with the extension of time,the extent and scope of the above changes gradually increase and were irreversible.2)Observation under light microscope showed that the morphology and structure of bronchus and alveoli in the control group were normal;the pathological changes of the lung tissue in the paraquat group from 2 hours to 14 days included local perivascular inflammatory cell infiltration and alveolar wall rupture,bronchial epithelial cytoplasmic vacuolation,and inflammatory cells infiltration around bronchus,local tissue hemorrhage with a large number of red blood cells in the alveolar cavity,local alveolar wall thickening with inflammatory cell infiltration,eosinophilic serous substance exudation in the alveolar cavity,local bronchial epithelium shedding,and large areas of capillary congestion and expansion in the tissue.As time goes on,the scope and extent of the above changes gradually increase and were irreversible2.Imaging changes of renal and lung:1)Compared with the control group,the RBF values of the paraquat group showed a downtrend with time passing,and the difference was statistically significant(F=4.285,P?0.05).2)Compared with the control group,Volume,Run length nonuniformity,Gray level nonuiformity,and Long run emphasis of the paraquat group showd a downtrend with time passing,among which the differences of Volume,Gray level nonuiformity,and Long run emphasis are statistically significant(F=5.739?4.429?5.829,P?0.05);while the Mean,Percentile(Perc.1%,Perc.10%,Perc.50%),Short run emphasis,and Fraction of image in runs showed an increasing tendency with time passing,and the differences of Mean,Perc.50%,Short run emphasis,and Fraction of image in runs are statistically significant(F=4.614?4.860?4.206?4.260,P?0.05).3)From 2 hours to 14 days in the paraquat group,the plain CT images of rabbits' lung were changed to initially visible thickening and disorder of the lung texture,and there were a few flaky ground-glass opacity.Subsequently,thickening of bronchial vascular bundle was accompanied by bronchiectasis and distortion,and local consolidation shadow was accompanied by air bronchial signs.Finally,pneumothorax formation at the side of the mediastinum and lateral chest wall could be seen.In the control group,the lung texture of the rabbits were clear at each time point,and there was no obvious exudation and solid changes in the bilateral lung field.3.Correlation between lung CT texture features and renal perfusion parameters:Compared with the control group,there was a linear correlation between the renal perfusion parameters RBF and nine lung CT texture features of the paraquat group,among which RBF was significant positive correlated with Volume,Gray level nonuiformity,and Long run emphasis(r=0.972,0.963,0.981,P?0.05),while with Mean,Perc 1%,Perc 10%,Perc 50%,and Short run emphasis,Fraction of image in runs showed a significant negative correlation(r=-0.981,-0.977,-0.989,-0.988,-0.970,-0.967,P?0.05).Conclusions:1.There is a certain correlation between lung injury and kidney injury after paraquat poisoning.Lung CT texture texture feature parameters such as Volume,Perc.50%,Gray level nonuiformity,etc.are used as imaging markers of paraquat poisoning lung injury,which is expected to be applied in clinical diagnosis and treatment of multi-organ injury caused by paraquat poisoning.2.The Volume,Mean,Perc.50%,Gray level nonuiformity,Long run emphasis,Short run emphasis,and Fraction of image in runs of lung CT texture feature parameters can be used to quantitatively evaluate the early changes of lung function injury after paraquat poisoning.3.Based on previous research,the renal perfusion imaging parameters RBF can be verified again to quantitatively evaluate the early changes in renal function after paraquat poisoning.