Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
Hôpital Kirchberg (Hôpitaux Robert Schuman), 9, Rue Edward Steichen, 2540, Luxembourg, Luxembourg.
Cardiovasc Intervent Radiol. 2020 Jun;43(6):918-923. doi: 10.1007/s00270-020-02453-1. Epub 2020 Mar 31.
The purpose of this study was to evaluate the heat generation of surgical clips within the target area of MWA and the influences on the ablation volume.
In bovine liver tissue, 42 ex vivo microwave ablations (60 W; 180 s) were performed. During ablation, the temperature was measured continuously at 4 points of interest (POI), in a distance of 7.5 and 15 mm on each side of the microwave antenna, with a titanium surgical placed at one 7.5-mm POI. Ablation volumes containing large vessels (n = 10) were excluded. For every POI, the mean temperature of 32 ablations was calculated. The mean temperatures were compared between the 4 POI and statistically analyzed using the Student's t test.
The mean maximum temperatures at the side of the clip were 88.76 °C/ 195 s and 52.97 °C/ 195 s and at the side without clip 78.75 °C/ 195 s and 43.16 °C/ 195 s, respectively, at POI 7.5 mm and POI 15 mm. The maximum difference of mean temperatures for POI 7.5 mm was 12.91 °C at 84 s (p = 0.022) and for POI 15 mm 9.77 °C at 195 s (p = 0.009). No significant changes in size and shape of the ablation zone could be determined.
Our study demonstrated significantly higher temperatures adjacent to surgical clips. Also, the temperatures distal to the titanium clip were higher compared to the control location without clip. These findings suggest an increased risk of thermal damage to surrounding tissues during MWA, especially in case of immediate contact to surgical clips.
本研究旨在评估微波消融（MWA）靶区内手术夹的产热情况及其对消融体积的影响。
在牛肝组织中进行了 42 次离体微波消融（60 W；180 s）。在消融过程中，连续在 4 个感兴趣点（POI）测量温度，微波天线两侧距离为 7.5 和 15 mm，在一个 7.5-mm POI 处放置钛制手术夹。排除含有大血管的消融体积（n = 10）。对于每个 POI，计算了 32 次消融的平均温度。通过学生 t 检验对 4 个 POI 的平均温度进行比较和统计学分析。
夹侧的平均最大温度分别为 88.76°C/195 s 和 52.97°C/195 s，无夹侧的平均最大温度分别为 78.75°C/195 s 和 43.16°C/195 s，在 7.5 mm 和 15 mm POI。POI 7.5 mm 处的平均温度最大差异为 12.91°C，在 84 s 时（p = 0.022），POI 15 mm 处的平均温度最大差异为 9.77°C，在 195 s 时（p = 0.009）。未确定消融区大小和形状的显著变化。
本研究表明，手术夹附近的温度明显升高。此外，与无夹控制位置相比，钛夹远端的温度更高。这些发现表明，MWA 过程中周围组织发生热损伤的风险增加，尤其是在与手术夹直接接触的情况下。
