Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
IMACTIS, 20 Rue du Tour de l'Eau, Grenoble, 38400, Saint-Martin-d'Hères, France.
Cardiovasc Intervent Radiol. 2021 Mar;44(3):500-506. doi: 10.1007/s00270-020-02761-6. Epub 2021 Jan 6.
To assess the accuracy and applicability of an electromagnetic navigation system (EMNS) for CT-guided microwave ablation (MWA) of hepatic tumors in comparison with conventional CT-guidance.
34 patients (m = 20/f = 14, mean age 34 y) with 34 liver tumors (primary = 22, metastases = 14, mean size 20 mm) referred for CT-guided MWA were included in this IRB-approved study. Interventions were performed prospectively using an EMNS in 17 patients (navigation group), and results were compared to a matched historic cohort of 17 patients using conventional CT-guidance (control group, t-test, p < 0.05 deemed significant). Primary outcome measurement: accuracy of antenna placement (deviation). Secondary outcome measurements: setup time, number of control scans, duration and radiation exposure for antenna placement.
Ablations were performed using a single or a double-angulated approach. Application of the EMNS was feasible in 14 cases (82%). Mean total deviation of the antenna feed point in the navigation and control group was 2.4 mm (range 0.2-4.8 mm) and 3.9 mm (range 0.4-7.8 mm), p < 0.05. Mean setup time for the EMNS was 6.75 ± 3.9 min (range 3-12 min). Mean number of control scans in the navigation and control group was 3 ± 0.9 (range 1-4) and 6 ± 1.3 (range 4-8), p < 0.0001; mean time for antenna placement was 9 ± 7.3 min (range 1.4-25.9 min) and 11.45 ± 6.1 min (range 3.9-27.4 min), p = 0.3164. Radiation exposure was significantly less in the navigation group.
Our experience in a limited number of patients suggests that EMNS enables intuitive CT-guided MWA of liver tumors with higher accuracy when compared to ablations performed without navigation and with fewer control scans needed.
评估电磁导航系统（EMNS）在 CT 引导下微波消融（MWA）肝肿瘤中的准确性和适用性，并与传统 CT 引导进行比较。
本研究经机构审查委员会批准，共纳入 34 例（男 20 例，女 14 例，平均年龄 34 岁）34 个肝脏肿瘤患者（原发性肿瘤 22 个，转移性肿瘤 14 个，平均大小 20mm），这些患者均接受 CT 引导下 MWA。17 例患者采用 EMNS 进行前瞻性干预（导航组），并与 17 例匹配的传统 CT 引导历史对照患者（对照组，t 检验，p<0.05 认为有统计学差异）进行比较。主要测量指标：天线放置的准确性（偏差）。次要测量指标：设置时间、控制扫描次数、天线放置时间和辐射暴露。
消融采用单或双角入路。EMNS 应用在 14 例（82%）中是可行的。导航组和对照组的天线馈电点总偏差分别为 2.4mm（范围 0.2-4.8mm）和 3.9mm（范围 0.4-7.8mm），p<0.05。EMNS 的平均设置时间为 6.75±3.9min（范围 3-12min）。导航组和对照组的平均控制扫描次数分别为 3±0.9（范围 1-4）和 6±1.3（范围 4-8），p<0.0001；天线放置的平均时间分别为 9±7.3min（范围 1.4-25.9min）和 11.45±6.1min（范围 3.9-27.4min），p=0.3164。导航组的辐射暴露明显较少。
在有限数量的患者中，我们的经验表明，与无导航和需要更少控制扫描的消融相比，EMNS 可实现更准确的 CT 引导下肝肿瘤 MWA，同时具有更高的准确性。
