双参数11C-MET PET/MRI在脑肿瘤样病变的初步应用

Dual-parametric C-MET PET/MRI in brain tumous lesions:preliminary report

目的:探讨双参数11C-MET PET/MRI检查在脑肿瘤样病变的诊断价值。方法:回顾性分析2013年1月至2016年12月间因"颅内占位"为主诉行11C-MET PET/MRI多模态脑显像的患者32例(男22例、女10例,年龄7~82岁),测量病灶及健侧正常脑组织的SUVmax,采用dipy工具包计算DKI数据(Kmax,Kmean及Kmin),以手术病理、临床最终诊断及治疗后随访为标准。结果 :恶性病变的SUVmax显著高于良性病变(Z=-3.04,P<0.01),其Kmean值显著低于良性病变(Z=-2.25,P<0.05)。恶性病变的Kmean值显著低于健侧参考区(t=-5.44,P<0.05),而良性病变的Kmean值未见显著性差异。ROC分析显示在良、恶性病变鉴别中SUVmax和Kmean值的AUC分别为0.85和0.77,对应的最佳阈值分别为4.7和2.1。双参数分析显示良、恶性病变存在明显不同的影像特征。结论:双参数MET-PET/MRI通过互补信息的整合分析,在脑肿瘤性病变的诊断及鉴别诊断中具有良好的应用价值。

Objectives:To explore the possibility of generating meaningful clinical advantage using anatomic,diffusion weighted,and Methionine PET images in intracranial lesions with suspicion of brain tumors.Methods:Retrospective analysis of the11 C-MET PET/MRI images of 32 patients(male:22,female:8,age range:7-72 years)with pathological and/or laboratory results confirmed brain benign processes(n=8)and malignancies(n=24).PET/MRI acquisition included a 10-min MET-PET scan,structural and diffusion weighted images.Data analysis:the diffusion kurtosis images(Kmax,Kmean and Kmin)were calculated using the dipy tools and the track density images were reconstructed from the MRtrix3 tools.Results:Both SUVmax(Z =-3.04,P <0.01)and Kmean values(Z=-2.25,P<0.05)of malignancy were significantly higher than those of benign.The Kmean value of malignancy was obviously lower than that of NTR(t=-5.44,P<0.05).No significance was detected neither in the comparison between benign and malignant lesions,nor between lesions and NTR for Kmax and Kmin.Area under the receiver operating characteristic curve was 0.85 for SUVmax and 0.77 for Kmean during testing to discriminate between benign and malignant lesions,with the cutoff value of 4.7 and 2.1,respectively.Dual-parametric(SUVmax and Kmean)2 D histogram shows different distribution patterns for benign and malignant diseases.Conclusion:Dual-parametric MET-PET/MRI analysis can provide morphological and metabolic informations of intracranial diseases,which may enhance the accuracy of pre-surgery diagnosis,determine the extension of tumor resection precisely,and even affect the choice of postoperative treatment.