基于有限元研究消痔灵注射治疗IRP型排便困难的机制

The Internal Rectal Prolapse(IRP) is one of the common reasons of difficult defecation. The applicant has proven that the Xiaozhiling is effective to the IRP, and found that the rigidity of the rabbit’s rectal mucosa after the injection was higher than ever before, and speculated that it was one of the mechanisms to relieve the difficult defecation of the IRP. This project will study three periods in making the IRP model.There are three groups which include blank group (normal feeding groups), model group and treatment group (Xiaozhiling injection groups) in each period. Firstly, through doing the defecography in the each group and measuring the indexes,such as the speed of the rectum. In this way, we can reflect the defecation objectively and verify the results of the finite elements. Then we will take the anorectum from the rabbits,and measure the mechanics indexes,such as elastic modulus of the rectal organization, entering the dataes to the finite element model. We simulate the defecate experiment in the model, calculating the shear stress and the displacement of different nodes under the stress to evaluate resistance of the the feces through the rectum. Finally, by studying the three ways which include Xiaozhiling injection treatment,the physical development and the pathological process,and analyzing the effect of the rectal different imaging signs in the defecation, we will summarize the effect of the rectal different mechanical forms in the defecation from the finite element data. We will analyse the mechanism of Xiaozhiling injection therapy on difficult defecations of the IRP by using the finite element theory combined with defecation imaging. The results will provide scientific basis for the treatment of the IRP.

直肠粘膜内脱垂（IRP）是排便困难发生的病因之一。申请人运用消痔灵注射治疗IRP兔已证实有效,并发现注射后兔直肠粘膜的刚性与注射前比较明显增强，推测其是治疗IRP型排便困难的机制之一。课题设计研究IRP兔造模的三个时期。将每个时期的兔分为空白组（正常饲养）、模型组与治疗组（消痔灵注射）。首先将各组兔进行排粪造影检查，测算粪便通过直肠的速度等指标，客观反映排便情况并验证有限元结果；其次解剖兔取肛门直肠测算组织的弹性模量等力学指标，输入兔肛门直肠有限元模型后模拟排便，在相同条件下计算不同节点的剪应力、位移量等指标，反映粪便通过直肠的受力情况；最后通过分析消痔灵注射治疗、生理过程与造模病理过程三种状态，研究直肠有限元节点的数据及影像学指标来探讨直肠的不同力学形态影响排便的机制。本项目首次运用有限元与排粪造影来研究消痔灵注射治疗IRP型排便困难的力学机制，结果将为IRP的治疗提供科学依据。

中医治疗直肠粘膜内脱垂（IRP）以消痔灵注射治疗为主，临床疗效显著。本课题主要分为IRP兔造模、消痔灵注射IRP兔、兔的排粪造影检查与不同时期兔肛门直肠有限元模型的建立及力学指标的测算四个部分。通过研究直肠有限元节点的数据，分析直肠不同影像对排便的影响，来探讨消痔灵注射治疗IRP型排便困难的力学机制。. 本研究主要结论如下：1、消痔灵注射后在肛管直肠角平面的直肠黏膜层与黏膜下层腹侧、中间为及背侧节点的弹性模量与内脱垂状态相比逐渐增大，提示在IRP兔肛管直肠角平面，粪块通过时阻力增大，消痔灵注射治疗后其阻力下降。2、与正常兔的直肠黏膜比较，位于肛管直肠角腹侧的综合应力降低，同一横断位不同冠状位的中间位与背侧综合应力均升高。而在消痔灵注射治疗IRP兔后，腹侧的综合应力升高，中间位及背侧的综合应力均降低，表明治疗后排便推力升高，粪便更容易通过直肠。3、排粪造影提示，消痔灵注射后，粪块通过直肠的速度较注射前状态明显加快。4、IRP兔易发生肠道逆蠕动现象，从而加重排便困难。 5、消痔灵注射液小剂量注射于肌肉，对组织的影响不大；大剂量则容易引起肌组织坏死，炎症逐渐沿周边筋膜扩散。 . 综上，本研究将有限元理论与排粪造影结合，消痔灵注射后提高直肠组织的刚性，从而促进粪便在肠道内的排出。结果将为消痔灵注射治疗 IRP型排便困难提供理论支持。