To evaluate clinicalimpact and benefits of trans-sphincteric injection of silicone in patients withanal incontinence using validated incontinence score and quality of life scale.35 incontinent patients related to internal and external anal sphincter defectswere selected for ambulatorial trans-sphincteric silicone injection. Inclusioncriteria were: anal incontinence associated or not to internal sphincter defectsand/ or one quadrant external sphincter defects. All patients were submittedto clinical evaluation before and after injections including an incontinencescoring system (Cleveland Clinic Florida) and quality of life scale (Fecal IncontinenceQuality of Life) with 4 domains: depression, self-perception, embarrassmentand lifestyle. Results: 28 female and 7 male patients with a mean age of 60.3(19-80)years underwent ambulatorial trans-sphincteric injection of silicone. Mean incontinencescore improved significantly after injection: 11.3 to 4.3 (p<0.001). Alldomains in the quality of life scale demonstrated significant improvement afterinjection (p<0.0001). Conclusion: In selected cases, trans-sphincteric siliconeinjection is a valuable option for the treatment of anal incontinence, improvingsignificantly patient's quality of life.