肝细胞癌高强度聚焦超声治疗后近期MR成像观察

目的分析原发性肝细胞癌高强度聚焦超声(high intensity focused ultrasound,HIFU)治疗后的MRI表现.方法21例经病理或临床诊断的原发性肝细胞癌患者在HIFU治疗前、后行腹部的轴位T1WI,轴位T2WI,冠状位SPIR,以及GD-DTPA增强后T1WI的轴位、FFE序列的冠状位扫描.在MRI图像上观察肿瘤在HIFU治疗前、后的大小及信号改变.结果HIFU治疗29个癌灶,其中24个缩小(82.76%),5个增大(17.24%);在T1WI增强上26个(89.66%)出现无信号增强区,12个癌灶无增强区周围见环状强化,7个强化环内见低信号环(T1WI、T2WI、SPIR).无强化区大多在T1WI表现为低信号或高信号,T2WI为低、等信号或高信号,SPIR序列为低、等信号或高信号,FE序列为低信号.结论HIFU治疗后,肝癌瘤灶内可出现多种MR信号改变,MR成像应成为肝癌HIFU治疗效果评估的一种无创而有效的方法.

MR imaging of hepatocellular carcinoma following the treatment of high intensity focused ultrasound

Objective To analyze the MRI findings of hepatocellular carcinoma (HCC) treated with high intensity focused ultrasound (HIFU). Methods Abdoman MR imaging was performed in 21 patients with HCC before and after HIFU treatment. The MR sequences included axial T1W SE, axial T2WI TSE, coronal SPIR, and GD-DTPA enhanced axial T1WI SE and coronal FFE. The changes of HCC carcinoma in size and signal were observed at MR images. Results Twenty-nine HCC lesions were treated by HIFU. The volume of 24 carcinomas (82.76%) shrinked, and 5 (17.24%) increased. At GD-DTPA enhanced T1W imaging, "no enhanced area" in 26 cancer lesions (89.7%) was observed, and enhanced ring in the boundary of the "no enhanced area" in 12 lesions were demonstrated. There was a dark ring between the enhanced boundary and the "no enhanced area" in 7 lesions at T1WI, T2WI and SPIR images. Most of the "no enhanced area" showed low or high intensity signal on T1WI, low, equal or high intensity signal on T2WI and SPIR sequence, low intensity signal on FFE sequence relative to surrounding hepatic parenchyma. Conclusion Various signal changes of hepatic carcinoma can be detected on different MR images following HIFU treatment. MRI could potentially provide a noninvasive observation for the effects of HIFU therapy on HCC.