Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Gulou district, Nanjing, 210029, Jiangsu, China.
Abdom Radiol (NY). 2017 Jun;42(6):1781-1787. doi: 10.1007/s00261-017-1064-0.
To compare the technical success and accuracy of hepatic microwave ablation (MWA) using non-enhanced and enhanced T1-weighted imaging early after ablation. Patients were evaluated with regard to the ablation zone and local tumor progression (LTP).
This retrospective study conducted between September 2014 and December 2015 which consisted of 56 patients with 56 hepatic malignant lesions who underwent percutaneous MWA. Non-enhanced and contrast-enhanced T1-weighted imagings were performed within 2 days after tumor ablation. The efficacy of ablation assessed according to the hyperintense middle zone on non-enhanced T1-weighted images and the non-enhanced area on contrast-enhanced T1-weighted images were compared. The development of LTP during ≥7 months of follow-up served as the end point.
On the non-enhanced T1-weighted images, the ablated region had a characteristic two-zone structure featuring a hyperintense middle zone and a surrounding hypointense band. Among the 56 patients, LTP developed in ten including seven lesions, in which both the non-enhanced T1-weighted and portal-phase images showed incomplete tumor ablation. In two of the remaining three patients, incomplete tumor ablation was detected on the non-enhanced T1-weighted images, whereas the corresponding portal-phase images showed complete ablation. In the remaining patient, no residual tumor was detected on either the non-enhanced T1-weighted or the portal-phase images. In the 46 patients without LTP, there was no evidence of residual tumor on the non-enhanced T1-weighted or portal-phase images obtained early after ablation.
Non-enhanced T1-weighted images are useful in assessing the therapeutic efficacy of MWA of liver tumors early after the procedure.
比较肝微波消融（MWA）术后即刻非增强和增强 T1 加权成像在技术成功率和准确性方面的差异，评估消融区域和局部肿瘤进展（LTP）。
本回顾性研究于 2014 年 9 月至 2015 年 12 月期间进行，共纳入 56 例 56 个肝恶性肿瘤患者，均接受经皮 MWA 治疗。肿瘤消融术后 2 天内行非增强和增强 T1 加权成像检查。根据非增强 T1 加权图像上的高信号中间区和增强 T1 加权图像上的无增强区评估消融效果，并进行比较。以≥7 个月随访期间 LTP 的发展为终点。
在非增强 T1 加权图像上，消融区域呈现出特征性的两区域结构，表现为高信号中间区和周围低信号带。在 56 例患者中，10 例（7 个病灶）发生 LTP，其中非增强 T1 加权图像和门静脉期图像均显示肿瘤不完全消融。在其余 3 例患者中的 2 例中，仅在非增强 T1 加权图像上检测到肿瘤不完全消融，而相应的门静脉期图像显示完全消融。在其余 1 例患者中，非增强 T1 加权图像和门静脉期图像上均未检测到残留肿瘤。在无 LTP 的 46 例患者中，术后即刻非增强 T1 加权图像和门静脉期图像均未见残留肿瘤。
非增强 T1 加权图像有助于评估肝肿瘤 MWA 术后即刻的疗效。
