Inclusion Criteria:
\- 1.18 to 85-year-old men and women. 2. People with moderate to severe functional constipation according to Rome IV criteria.
The Rome IV criteria for functional constipation are as follows:
1. Must include two or more of the following:
* Straining during more than one-fourth (25%) of defecations;
* Lumpy or hard stools (BSFS 1-2) more than one-fourth (25%) of defecations;
* Sensation of incomplete evacuation more than one-fourth (25%) of defecations;
* Sensation of anorectal obstruction/blockage more than one-fourth (25%) of defecations;
* Manual maneuvers to facilitate more than one fourth (25%) of defecations (e.g., digital evacuation, support of the pelvic floor);
* Fewer than 3 spontaneous bowel movements per week;
2. Loose stools are rarely present without the use of laxatives.
3. Insufficient criteria for irritable bowel syndrome Criteria fulfilled for the last three months with symptom onset at least six months prior to diagnosis.
Severity of constipation:
1. Mild: The symptoms are mild and do not affect daily life. Normal BMs can be restored through overall adjustment and medication use in a short time.
2. Moderate: The symptoms are between mild and severe symptoms.
3. Severe: The symptoms are severe and persistent, seriously affecting work and life, and requiring medications, and medications cannot be stopped, or medications are ineffective.
3\. People who had a colonoscopy within three years before screening and had negative results, or whose colonoscopy results are judged by the investigator as mild anomalies, but the cause of their constipation cannot be explained. If the colonoscopy report is unavailable, the study physician will determine if a colonoscopy is needed. If the subjects undergo a colonoscopy after signing the ICF, they will not enter the treatment period until their BMs return to the baseline level (which takes about 1-4 weeks).
4\. People had colonic polyps and a polypectomy (except for endoscopic submucosal dissection (ESD)). Those with a polyp ≤1 cm can be enrolled one month after the polypectomy. Those with a polyp \>1 cm can be enrolled three months after the polypectomy.
5\. People who consent to participate in this trial, can communicate with the investigator, understand and comply with the relevant procedures and requirements during the study (including completing study questionnaires on time, being treated and visited as scheduled, and undergoing relevant examinations), and voluntarily sign the ICF.
Exclusion Criteria:
1. People who are not eligible for surgery or refuse to undergo any abdominal surgery.
2. People with known or suspected gastrointestinal obstruction, stenosis, diverticulum, bleeding, malformation, and fistula.
3. People allergic to polymeric materials.
4. People implanted with cardiac pacemakers and using gastrointestinal pacemakers.
5. People with abdominal aortic aneurysms, gastrointestinal vascular lesions, ulcers, and lesions with bleeding tendencies.
6. People with dysphagia.
7. People with severe depression and anxiety and severe acute gastrointestinal lesions.
8. People who had gastrointestinal surgery or a history of surgery that changed the structure of the gastrointestinal tract (except for appendectomy) or people who underwent gastrointestinal ESD in the past three months.
9. People with severe hemorrhoids (patients with grade III-IV hemorrhoids according to the Clinical Practice Guidelines for the Management of Hemorrhoids of the American Society of Colon and Rectal Surgeons).
10. People who plan to undergo MRI in the near future.
11. Pregnant women or women with pregnancy plans in the next year.
12. People with other conditions, so the investigator considers them not eligible for this study.
