Preliminary study of a novel artificial anal sphincter with perception reconstruction

• Published in: Artificial organs 2022-05, Vol.46 (5), p.794-803
• Main Authors: Han, Ding, Yan, Guozheng, Hua, Fangfang, Wang, Lichao
• Format: Article
• Language: English
• Subjects: Anal Canal - surgery; artificial anal sphincter; Artificial Organs; cam‐follower transmission structure; Clamping; Design optimization; Fecal Incontinence - surgery; Humans; in vitro experiments; In vitro methods and tests; Modules; Perception; Pressure; Pressure sensors; rectal perception reconstruction; Rectum; Reliability engineering; Reproducibility of Results; Safety; Sensors; Sphincter; strain gauge pressure sensor; Strain gauges; Structural reliability
• ISSN: 0160-564X; 1525-1594
• DOI: 10.1111/aor.14129

Background Artificial anal sphincter (AAS), as an advanced device, has been widely investigated by researchers around world. But the reliability of the structure is still unsatisfactory according to clinical results. What's more, the previous AAS systems are lack the ability of rectal perception as native anal sphincter, which fails to guarantee the safety of the blood supply. In addition, without it, the patient cannot determine when to defecate. Methods In order to improve the reliability and safety of current AAS systems, a novel structure AAS system with rectal perception function, based on pressure sensor module, is proposed in this article. The novel AAS system has a closed three‐arm clamping mechanism, with transmission structure of cam‐follower system. Then, the design, strength check, optimization and force analysis of the proposed mechanism are investigated. After that, to remodel rectal perception function, the novel sensor module system based on strain gauge is established. Finally, in vitro experiments are conducted. Results In vitro test, the sensor system could monitor the rectal pressure accurately. And when H = 24.6 cm (feeling the urge to have a bowel movement), the clamping pressure is 7.39 kPa. which is also less than the safe pressure 9.33 kPa. Conclusions Good performance of the reliability and safety of both novel rectal perception function and new clamping mechanism have been showed. The new AAS system has designed a closed three‐arm sphincter prosthesis. Controlling defecation by clamping the intestine to form an anorectal angle, compared with traditional device. Furthermore, 10‐channel pressure sensor modules have been established to rebuild rectal perception function, which can provide accurate and reliable sense ability.