介入治疗有效肝癌术后MRI信号的动态定量观测

Dynamic Quantitative Assessment of Magnetic Resonance Signals of Hepatocellular Carcinoma Before and After Effective Interventional Therapy

目的研究介入治疗有效的较小肝癌,治疗后1年内肿块磁共振成像（MRI）信号变化的规律。方法纳入肝动脉灌注化疗栓塞术治疗后1年内无复发的肝癌患者43例,共52个病灶,收集其介入治疗前及治疗后1~3个月、3~6个月、6~12个月的MRI检查资料,回顾性测量病灶及邻近肝组织的信号强度（signal intensity,SI）值,计算病灶与周围肝组织SI值的相对值（signal intensity ratio,SIR）,分析病灶SI和SIR的动态变化规律。结果T1WI脂肪抑制序列平扫及增强三期显示,介入治疗后1~3个月,90.38%（47/52）的病灶SI及SIR值升高,96.15%（50/52）的病灶于治疗后3~6个月升至峰值,介入治疗后6~12个月94.23%（49/52）的病灶SI值及SIR值呈降低趋势。T2WI脂肪抑制序列,98.08%（51/52）的病灶SI和SIR值呈缓慢降低趋势。同时,T1WI、T2WI及T1WI增强三期SI和SIR值比较,差异均有统计学意义（P〈0.05）。结论较小肝癌介入治疗后1年内,MRI T1WI平扫及动态增强三期SI值与SIR值呈抛物线样变化,T2WI序列呈单向降低变化;SI值及SIR值的动态测量具有定量评价原发性肝癌介入治疗疗效的价值。

Objective To study the changes of magnetic resonance signal intensity（SI）of relatively small hepatocellular carcinoma within the first year after the effective interventional therapy.Methods Forty-three patients with a total of 52 relatively small hepatocellular carcinoma（less than 4cm in diameter）who had no recurrence within the first year after the treatment of hepatic artery infusion chemotherapy and embolization were enrolled into this study.All the patients underwent magnetic resonance imaging（MRI）before the effective interventional therapy and during the periods of 1-3 months,3-6 months and 6-12 months after the therapy respectively,and the image data were collected and reviewed retrospectively.The signal intensity of the cancer and its adjacent liver tissues were measured at each magnetic resonance sequence.Subsequently,the relative signal intensity ratio（SIR）of SI in the lesion and the adjacent liver tissues was calculated,and the dynamic changes of SI and SIR in the lesions during the follow-ups were analyzed.Results T1 weighted fat-suppression sequence scanning and triple-phase enhanced scanning indicated that the SI and SIR increased in the 90.38% of the lesions（47of the52）during the period of 1-3months and reached the peak in the 96.15% of the lesions（50of the 52）during the period of 3-6 months,but it began to decrease in the 94.23% of the lesions（49of the 52）during the period of 6-12 months after the effective interventional therapy.T2 weighted fat-suppression sequence scanning showed that the SI and SIR decreased slowly in the 98.08% of the lesions（51of the 52）.There were significant differences in the values of SI and SIR among the arterial phase,portal phase and parenchymal phase（P0.05）.Conclusion The SI and SIR of hepatocellular carcinoma change as a curve with a single peak in the T1 weighted fat-suppression and triple-phase enhanced scanning and reduce unilaterally in the T2 weighted imaging during the first year after the effective interventional therapy.The dynamic measurement of SI and SIR can be used to assess the therapeutic efficacy of hepatocellular carcinoma quantitatively after the effective interventional therapy.