18F-FDG PET/MR与PET/CT在肝脏肿瘤诊断中的初步对比研究

Preliminary Comparative Study of PET/MR and PET/CT in Diagnosis of Liver Tumors

目的比较分析一体化PET/MR与PET/CT在肝脏肿瘤诊断中的差异。方法回顾性分析93例怀疑肝脏肿瘤的患者,同日先后行全身18F-FDG PET/CT显像及PET/MR局部显像的相关资料。用Pearson相关性分析、Bland-Altman分析及t检验对两者的信噪比(SNR),SUVmax及靶区/本底比值(Tissue/Backgroud,T/B)进行比较分析。运用χ2检验比较两者显像结果的差异。结果93例中,63例确诊肝脏恶性肿瘤。PET-MR图像SNR及T/B值较PET-CT高,有显著统计学差异(t=9.63,3.45,P<0.01)。66.7%(62/93)的病例PET/MR比PET/CT多发现肝脏病灶,包括恶性50例,两者具有显著统计学差异(χ2=93.00,P<0.01);其中39例病例PET/MR比PET/CT有更多的PET阳性病灶,有显著统计学差异(χ2=34.65,P<0.01)。结论PET/MR对肝脏肿瘤有较高的诊断价值。与PET/CT相比,PET/MR的PET图像信噪比及靶本比更高,PET阳性率更高,MR提供的诊断信息更多,病灶检出率更高。

Objective The purpose of this study is to compare the difference between a hybrid TOF PET/MR and PET/CT in the diagnosis of liver tumors.Methods 93 patients suspected of liver tumor,were performed whole body 18F-FDG PET/CT imaging and 18F-FDG PET/MR(T1,T2 and DWI)localized examination on the same day.The Pearson correlation analysis,Bland-Altman analysis and t test were applied to analyze the signal-to-noise ratio(SNR),SUVmax and the T/N values in two PET imaging.χ2 test was used to compare the difference between the two imaging results.Results In the 93 cases,63 cases were liver tumors.In 66.7%(62/93)cases,PET/MR found more liver lesions than PET/CT,including 50 malignant cases(53.8%),with significant statistical differences(χ2=93.00,P<0.01).More lesions with 18F-FDG uptake higher than normal liver background were found in PET/MR comparing with PET/CT in 39 cases.There was significant statistical difference(χ2=34.65,P<0.01)between detection efficiency of PET in PET/MR and PET in PET/CT.The SNR and T/B(PET-MR)was greater than that in PET-CT with significant difference(t=9.63,3.45,P<0.01).Conclusion Hybrid PET/MR imaging provides valuable diagnosis for liver space occupying lesions.Compared with PET/CT,there was better image resolution and signal-to-noise ratio(SNR)in PET imaging,and MR provides more diagnostic information.Especially,the lesion detection rate of PET/MR is much better.