适用于大鼠小肠吻合的磁吻合装置的吻合力控制试验研究

Experimental study on anastomosis force control of magnetic compression device for small intestine anastomose in rats

目的:利用“磁芯”设计实现用于大鼠小肠吻合的磁吻合装置的吻合力控制,并探究不同吻合力对吻合口的影响。方法:将N54钕-铁-硼材料冲压成直径1、2、3、4、5、6 mm,厚1 mm的6种扁圆柱形磁体(依次记为组1、组2、组3、组4、组5、组6),在扁圆柱形磁体外包裹环形光敏树脂外壳(组6除外),制作吻合力不同(组1、组2、组3、组4、组5、组6分别为0.09、0.31、0.79、1.90、2.94、4.32 N)但结构和尺寸一致的6组磁吻合装置。在大鼠小肠吻合中应用上述吻合装置,观察不同吻合力下吻合口的粘连情况、爆破压、组织结构和动物生存等指标间的差异。结果:组1磁力过小,难以维持磁体稳定配对,未进行动物试验;组2子、母磁体发生解离,吻合失败;组3、组4、组5、组6试验动物分别死亡1、0、5、6只。组3、组4吻合口愈合良好、粘连少、机械强度高,组5、组6吻合口愈合差、粘连严重、机械强度较差。结论:大鼠小肠吻合最适吻合力为0.79~1.90 N。通过“磁芯”设计可将吻合力控制在最适范围,同时不改变磁吻合装置的结构与尺寸,最终实现安全、有效的小肠吻合。

Objective To design a magnetic core to control the anastomosis force of a magnetic anastomosis device for small intestine anastomose in rats,and to investigate the effect of different anastomosis forces on the anastomosis.Methods The N54 NdFeB material was stamped into 6 types of flat cylindrical magnets with diameters of 1,2,3,4,5 and 6 mm and thickness of 1 mm(marked as group 1 to 6 in order),and the cylindrical magnets were wrapped with a ring-shaped photosensitive resin shell(except group 6)to form six groups of magnetic compression devices with different anastomosis force(0.09,0.31,0.79,1.90,2.94 and 4.32 N respectively for group 1 to 6)while the same structure and dimensions.Then the magnetic compression devices were applied to rat small intestine anastomoses to observe the differences in adhesions,burst pressure,tissue structure and animal survival between the anastomoses with different anastomosis forces.Results The magnetic force of group 1 was too small to maintain a stable pairing of the magnets,and no animal experiments were carried out;the master and sub links aparted from each other in group 2 and anastomosis failed;there were 1,0,5 and 6 experimental animals died in group 3,4,5 and 6,respectively;group 3 and 4 behaved better than group 5 and 6 in anastomosis healing,few adhesions and high mechanical strength.Conclusion The optimal anastomosis force was 0.79 to 1.90 N for small intestine anastomoses in rats.The magnetic core designed contributes to controlling the anastomotic force in the optimal range without changing the structure and dimensions of the magnetic compression device,resulting in a safe and effective small intestine anastomosis.[Chinese Medical Equipment Journal,2023,44(5):26-30]