肝癌射频消融术后MRI表现及疗效

摘要

PurposeWith the extensive use of percutaneous radiofrequency ablation (RFA) for the treatment of hepatic carcinoma (HC), the study of MRI findings and its clinical signiifcance after RFA of HC have important value and can improve the complete ablation rate.Materials and MethodsA retrospective analysis of post-procedure MRI ifndings of 79 patients (114 lesions) with HC were performed, the size of the lesion, the signal changes and enhancement condition were observed at the ifrst, fourth and seventh month after RFA; the two different ifndings of high signal ring on MRI T1WI and local recurrence rate were analyzed.ResultsOne month after RFA, peripheral region of RFA lesion showed high signal on T1WI, and slightly lower signal on T2WI, the size of lesions was slightly larger than pre-procedure, enhancement scan showed the thin homogeneous ring enhanced around the non-enhanced lesions; 4 months later, the size of lesions were relative stable and the periphery enhancement was weaken; 7 months later, the size of lesions were reduced and showed no enhancement. For recurrence lesions, the high signal ring was incomplete on TIWI, the incomplete area showed nodular enhancement on the arterial phase, and most of nodule showed slightly lower signal on the delay phase demonstrated a feature of "quick wash-in and wash-out"; 7 months after RFA, recurrence rate was 6.12% in patients with complete high signal ring and 43.75% in patients with incomplete high signal ring, the difference was statistically significant (P<0.05). The total survival rate and accumulated survival rate of the patients with complete high signal ring on T1WI were higher than the patients with incomplete ring, the difference was statistically signiifcant (P<0.05).ConclusionThere are characteristic ifndings of MRI examination of liver cancer after percutaneous RFA, observation of the integrity of high signal ring on T1WI image and ifnding of dynamic enhancement scan can early evaluate efifcacy of RFA guide the selection of treatment plan.%目的：经皮穿刺射频消融（RFA）广泛应用于肝癌的治疗，本研究分析肝癌RFA术后的MRI表现及疗效，以提高肿瘤的完全消融率。资料与方法回顾性分析79例（共114个病灶）肝癌患者经皮RFA术后的MRI表现，包括RFA术后1个月、4个月及7个月的病灶大小、信号变化及强化情况；分析术后消融灶两种不同MRI T1WI高信号环表现及肿瘤局部复发率。结果肝癌RFA术后1个月病灶周边在T1WI呈高信号，T2WI呈稍低信号，病灶范围较前稍增大，增强扫描病灶周围呈薄层均匀环形强化，中心区无强化；术后4个月病灶大小相对稳定，病灶周围强化减弱；术后7个月病灶范围较术前缩小，病灶未见明显强化。肝癌复发者，消融灶T1WI高信号环不完整，不完整区增强扫描动脉期呈结节状强化，延时期大部分呈稍低信号，呈“快进快出”的强化特点。T1WI高信号环完整组与不完整组术后7个月复发率分别为6.12%、43.75%，差异有统计学意义（P<0.05）。T1WI高信号环完整组总生存率及无瘤生存率均较T1WI高信号环不完整组高，差异有统计学意义（P<0.05）。结论肝癌经皮穿刺RFA术后的MRI检查具有特征性的表现，通过T1WI高信号环的完整性及动态增强扫描的表现能早期提示肝癌RFA术后的疗效，指导临床尽早选择治疗方案。