BACKGROUND Monopolar instruments are generally used in colorectal endoscopic mucosal resection (EMR). Bipolar instruments have previously been reported to be as safe as monopolar instruments. We sought to compare the safety of the monopolar and bipolar snare and hemostatic forceps in an animal model. METHODS We created 5-mm, 10-mm, and 15-mm target lesions on an ex vivo porcine rectum. Two lesions of each size were resected via monopolar polypectomy (M-P), monopolar EMR (M-E), bipolar polypectomy (B-P), and bipolar EMR (B-E). We performed a pathological evaluation of the conditions of perforation and the effects of burning on the tissues. In addition, we burned the muscularis propria covered with submucosal layer using monopolar and bipolar hemostatic forceps and performed pathological evaluations. RESULTS Polypectomy and EMR were performed in a total of 24 target lesions. A perforation was found on histology in one case of M-P and one case of M-E after removing target lesions of 15 mm in diameter. There were no perforations during endoscopic resection using the bipolar snare. The thermal denaturation in B-P did not reach the muscularis propria layer regardless of the size of the target lesion. Although thermal damage after using monopolar hemostatic forceps was extensive, thermal denaturation was only seen on the surface of the submucosal layer when bipolar hemostatic forceps were used. CONCLUSIONS Bipolar instruments cause less damage to the tissue than monopolar instruments. Our results also suggest that bipolar instruments may be safer than monopolar instruments in endoscopic procedures for colorectal lesions.

中文翻译：

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在离体猪模型中使用单极器械与双极器械进行内窥镜检查的安全性。

背景技术单极器械通常用于结直肠内窥镜粘膜切除术（EMR）。以前已经报道过双极仪器与单极仪器一样安全。我们试图在动物模型中比较单极和双极圈套器和止血钳的安全性。方法我们在离体猪直肠上创建了5毫米，10毫米和15毫米的目标病变。通过单极息肉切除术（MP），单极EMR（​​ME），双极息肉切除术（BP）和双极EMR（​​BE）切除每种大小的两个病变。我们对穿孔条件和烧伤组织进行了病理评估。此外，我们使用单极和双极止血钳烧毁了粘膜下层覆盖的固有肌层，并进行了病理评估。结果在总共24个靶病变中进行了息肉切除术和EMR。在切除直径为15 mm的目标病变后，在1例MP和1​​例ME的组织学上发现了穿孔。使用双极圈套器的内窥镜切除术中没有穿孔。不论目标病变的大小如何，BP的热变性均未到达固有肌层。尽管使用单极止血钳后的热损伤是广泛的，但是当使用双极止血钳时仅在粘膜下层的表面可见热变性。结论双极器械比单极器械对组织的损伤小。我们的研究结果还表明，在大肠病变的内窥镜检查中，双极器械可能比单极器械更安全。