Mechanisms of Action on Rectal Motricity of Intrarectal Botulinum Toxin Injections (MECA-TOX)

Inclusion Criteria: Active or predominantly active fecal incontinence with failure of 1st-line conservative treatments (normalization of transit, perineal re-education) Impairment of quality of life at investigator's discretion Patients at least 18 years of age Patients who have read and understood the information letter and signed the consent form Patients affiliated to the French Social Security system Women of childbearing age using effective contraception (Cf. CTFG) (estro- progestins or intrauterine device or tubal ligation) for at least 1 month and a negative B-HCG urine pregnancy test at inclusion and for the duration of the study. Postmenopausal women: confirmatory diagnosis (non-medically induced amenorrhea for at least 12 months prior to inclusion visit) Exclusion Criteria: General Pregnant women, women in labor, breastfeeding women, or women without proven contraception Patient deprived of liberty by administrative or judicial decision, or protected adult (under guardianship or trusteeship) Exclusive passive fecal incontinence Patient suffering from constipation (Rome IV criteria) Patient with an evolving inflammatory or cancerous digestive pathology Previous rectal surgery Person participating in another research protocol or having participated in another research protocol in the 4 weeks preceding the inclusion visit Linked to botulinum toxin injections Hypersensitivity to botulinum toxin or to one of the excipients (human albumin, sodium chloride) Neuromuscular junction pathology (myasthenia, Lambert-Eaton syndrome, etc.) Presence of infection at injection site(s) General anesthesia less than one month ago Association with aminoglycosides and anti-cholinesterase agents (risk of increased toxin effects) History of neurogenic damage such as polyradiculoneuritis History of dysphagia with esophageal or neurological stasis, swallowing disorders, inhalation pneumonitis Botulinum toxin injections in the 3 months preceding the study Clinical anal examination suggestive of anorectal abscess Recent history (<12 months) of myocardial infarction and/or rhythm disorders not reduced by appropriate treatment Peripheral motor neuropathies (such as amyotrophic lateral sclerosis or motor neuropathy) and underlying neurological disorders Current treatment with anticoagulants or anti-aggregants or haemostasis disorders according to recommendations (SFED). When patients are on anticoagulant or anti-aggregant therapy, the type of injections to be performed depends on the type of anticoagulation and the patient's thrombo-embolic risk: Patients on anticoagulant or anti-aggregant therapy with a major thrombo-embolic risk will not be included. Patients on anticoagulant or anti-aggregant therapy with a moderate or low thrombo-embolic risk may be included. If patients are taking a vitamin K antagonist, treatment will be continued provided that the INR is within the usual range of 2 to 3 (GETED, HAS, 2008). If patients are taking anti-aggregants, these can be continued (SFED, HAS, 2012). If patients are taking new oral anticoagulants, they should take a short break and not take the AOD the evening before or the morning of the injections (GIHP, 2015). Linked to rectosigmoidoscopy Local pathology preventing colonoscopy (anal stenosis) Allergy or hypersensitivity to silicone and/or latex Linked to laxatives Contraindication to DULCOLAX® 5 mg, gastro-resistant coated tablet Contraindication to XIMEPEG®, powder for oral solution Linked to high-resolution manometry Clinically diagnosed intestinal obstruction Severe coagulopathy or oral anticoagulants Cardiac disorders for which vagal stimulation is poorly tolerated