Analysis Of The Biological Viability Of Cerebral Alveolar Echinococcosis In The Marginal Zone:A Comparison Between Magnetic Resonance Perfusion And ¹⁸F-FDG PET/CT

Objective:To evaluate the blood supply mechanism and biological activity of the parenchyma and margin regions of Cerebral alveolar echinococcosis lesion based on the perfusion characteristics of Perfusion-weighted imaging technique.The results were compared with the SUV_max value of PET/CT to evaluate the application value of PWI in the activity of CAE.Methods:17 patients with CAE who met the inclusion criteria during the period of September 2014^January 2020 were collected.All of them were examined by routine brain MR enhancement scanning and magnetic resonance perfusion?PWI?examination using GE3.0T Signa Hdx System MR equipment,and a total of 31lesions were selected.Using GE ADW4.4 post-treatment workstation to analyze the PWI imaging of CAE disease,to compare the changes of PWI perfusion indexes in parenchymal region,margin region,edema region,and contralateral normal region of the lesion,and the four PWI parameter indexes of each region of the lesion were measured:relative cerebral blood flow?rCBF?,relative cerebral blood volume?rCBV?,mean passing time?MTT?,peak time?TTP?.The differences between the above PWI parameter values in the parenchymal,marginal,edema and contralateral normal regions of the lesion were statistically compared.We also collected the simultaneous FDG-PET examination of 10 CAE patients,selected 16 lesions with the same magnetic resonance perfusion examination,compared the differences of PET-SUV_max values in each region of the lesion,and analyzed the Spearman correlation statistically between the rCBF?rCBV?MTT?TTP parameters indexes and PET-SUV_max index in the marginal region of the CAE lesion.Using statistical method to further analyzes the ROC curve of diagnosis of PWI index and PET/CT index which have statistical difference between marginal area of CAE lesion and normal brain tissue of control side in the marginal zone of CAE disease.Results:The rCBF?rCBV values of the marginal region were higher than those of the parenchymal region,and the TTP values of the marginal region were lower than those of the parenchymal region,the overall distribution was statistically different?P<0.05?,The rCBF?rCBV values of each region in the CAE lesion were compared,showing the marginal region>the contralateral normal region?or the edema region?>parenchymal region,The rCBF?rCBV value of the marginal region was the highest in all region of the CAE lesion,which in the parenchymal region was the lowest.the results showed that the blood supply was the most abundant in the margin of the lesion,the parenchymal region was lack of blood supply due to the mass of necrotic material.The results of Spearman correlation analysis showed that there was a negative correlation between the TTP values at the edge area of CAE lesions and the PET-SUV_maxax values in the same region?r=-0.319,P<0.05?,and the other rCBF?rCBV?MTT indexes had no significant correlation with the SUV values.The ROC curve analysis of rCBF?rCBV?SUV_max parameters shows that AUCrCBF=0.845?P<0.05?,AUCrCBV=0.828?P<0.05?,AUCSUV_max=0.856?P<0.05?.Conclusion:PWI imaging can evaluate the activity of CAE lesions by evaluating the blood supply and perfusion at the inside and marginal region of the lesion,the results of TTP parameter value are correlated with the SUV_max value,suggesting that Perfusion-weighted imaging is expected to be recommended for clinical application as a more practical new technique without conditional PET/CT examination to judge the lesion activity.