全瘤及瘤周感兴趣体积双区域T1 mapping定量参数结合钆塞酸二钠增强MRI对肝细胞癌微血管侵犯的评估价值

Value of quantitative parameters of T1 mapping obtained from volume of interest of tumor and peritumoral combined with gadoxetic acid-enhanced MRI in evaluating microvascular invasion of hepatocellular carcinoma

目的探讨全瘤及瘤周感兴趣体积(VOI)双区域T1 mapping定量参数结合钆塞酸二钠增强MRI对肝细胞癌微血管侵犯(MVI)的评估价值。方法对我院2019年1月~2022年9月术后病理诊断为单发性肝细胞癌的72例患者进行回顾性分析,并根据MVI表达状态分为MVI阳性组(n=23)、MVI阴性组(n=49)。术前行钆塞酸二钠增强MRI T1 mapping扫描,得到平扫(Pre)、肝胆期(HBP)两期的T1 mapping图像。利用3D Slicer软件逐层勾画出全瘤(tumor)、瘤周(peritumor)、全瘤+瘤周的VOI并得到VOI_(tumor)、VOI_(peritumor 1 cm)、VOI_(peritumor 2 cm)、VOI_(tumor+1 cm)、VOI_(tumor+2 cm),测量出各个VOI的定量参数—T1弛豫时间(T1rt)和T1弛豫时间减低率(rrT1rt),比较MVI阳性组及阴性组间定量参数的差异,采用ROC曲线和净重分类指数(NRI)分析各定量参数的诊断效能。结果两组间T1rt-Pre-VOI_(tumor)、T1rt-Pre-VOI_(peritumor 1 cm)、T1rt-Pre-VOI_(tumor+1 cm)、T1rt-Pre-VOI_(tumor+2 cm)、T1rt-HBP-VOI_(tumor)、T1rt-HBP-VOI_(tumor+1 cm)、T1rt-HBP-VOI_(tumor+2 cm)、rrT1rt-VOI_(tumor+2 cm)差异均有统计学意义(P<0.05),其AUC值为0.720、0.689、0.748、0.730、0.727、0.726、0.717、0.639。多期参数T1rt-Pre-HBP-VOI_(tumor)、T1rt-Pre-HBP-VOI_(tumor+1 cm)、T1rt-Pre-HBP-VOI_(tumor+2 cm)的AUC值为0.740、0.756、0.743,其中T1rt-Pre-HBP-VOI_(tumor+1 cm)的诊断效能最高。NRI分析得出T1rt-Pre-VOI_(tumor+1 cm)、T1rt-HBP-VOI_(tumor+1 cm)与T1rt-Pre-VOI_(tumor+2 cm)、T1rt-HBP-VOI_(tumor+2 cm)比较均具有正向改善,NRI值为0.6158、0.4011。T1rt-Pre-HBP-VOI_(tumor+1 cm)分别与T1rt-Pre-VOI_(tumor+1 cm)、T1rt-HBP-VOI_(tumor+1 cm)比较均具有正向改善,NRI值分别为0.0692、0.5643。结论平扫、肝胆期的全瘤T1弛豫时间具有较好的诊断效能,且结合瘤周1 cm的T1弛豫时间诊断效能高于结合瘤周2 cm。多期T1弛豫时间的诊断效能高于单期,T1rt-Pre-HBP-VOI_(tumor+1 cm)诊断效能最高。

Objective To investigate the value of dual-region T1 mapping quantitative parameters of whole tumor and peritumoral volume of interest(VOI)combined with GD-EOB-DTPA enhanced MRI in evaluating microvascular invasion(MVI)of hepatocellular carcinoma.Methods From January 2019 to September 2022,72 patients with single hepatocellular carcinoma diagnosed by postoperative pathology in our hospital were retrospectively analyzed.According to the expression status of MVI,it was divided into MVI positive group(n=23)and MVI negative group(n=49).GD-EOB-DTPA enhanced MRI T1 mapping scan was performed before operation,and T1 mapping images of pre-enhancement phase(Pre)and hepatobiliary phase(HBP)were obtained.The VOI of tumor,peritumoral and tumor plus peritumor were drawn layer by layer by using 3D Slicer software and VOI_(tumor),VOI_(peritumor 1 cm),VOI_(peritumor 2 cm),VOI_(tumor+1 cm),VOI_(tumor+2 cm) were obtained.The quantitative parameters of each VOI,T1 relaxation time(T1rt)and T1 relaxation time reduction rate(rrT1rt)were measured.We compared the differences of quantitative parameters between the two groups.ROC curve and net reclassification index(NRI)were used to analyze the diagnostic efficacy of each quantitative parameter.Results T1rt-Pre-VOI_(tumor),T1rt-Pre-VOI_(peritumor 1 cm),T1rt-Pre-VOI_(tumor+1 cm),T1rt-Pre-VOI_(tumor+2 cm),T1rt-HBP-VOI_(tumor),T1rt-HBP-VOI_(tumor+1 cm),T1rt-HBP-VOI_(tumor+2 cm),rrT1rt-VOI_(tumor+2 cm) between the two groups were statistically significant(P<0.05).The AUC were 0.720,0.689,0.748,0.730,0.727,0.726,0.717,0.639.The AUC of multiphase quantitative parameter,T1rt-Pre-HBP-VOI_(tumor),T1rt-Pre-HBP-VOI_(tumor+1 cm),T1rt-Pre-HBP-VOI_(tumor+2 cm),were 0.740,0.756,0.743,among which T1rt-Pre-HBP-VOI_(tumor+1 cm) had the highest diagnostic efficiency.NRI analysis showed that T1rt-Pre-VOI_(tumor+1 cm),T1rt-HBP-VOI_(tumor+1 cm) had positive improvement compared with T1rt-Pre-VOI_(tumor+2 cm),T1rt-HBP-VOI_(tumor+2 cm).NRI values were 0.6158 and 0.4011.T1rt-Pre-HBP-VOI_(tumor+1 cm) showed positive improvement compared with T1rt-Pre-VOItumo1 cm and T1rt-HBPVOI_(tumor+1 cm),and the NRI values were 0.0692 and 0.5643,respectively.Conclusion The T1 relaxation time of tumor in Pre and HBP has good diagnostic efficacy for microvascular invasion in hepatocellular carcinoma.Combined with peritumoral 1 cm has higher diagnostic efficacy than peritumoral 2 cm.The diagnostic efficacy of multiphase quantitative parameter is higher than single-phase quantitative parameter and T1rt-Pre-HBP-VOI_(tumor+1 cm) is the highest.