Background: High-grade internal rectal prolapse appears to be one of the contributing factors in the multifactorial origin of faecal incontinence. Whether it affects the outcome of sacral neuromodulation is unknown. We compared the functional results of sacral neuromodulation for faecal incontinence in patients with and without a high-grade internal rectal prolapse.
Method: One hundred six consecutive patients suffering from faecal incontinence, who were eligible for sacral neuromodulation between 2009 and 2012, were identified from a prospective database. All patients underwent preoperative defaecating proctography, anorectal manometry and ultrasound. Symptoms were assessed preoperatively and at 12 months after operation using a standardized questionnaire incorporating the Faecal Incontinence Severity Index (FISI range = 0-61) and the Gastrointestinal Quality of Life Index (GIQLI). Success was defined as a decrease in the FISI score of 50 % or more.
Results: High-grade internal rectal prolapse (HIRP) was found in 36 patients (34%). The patient characteristics were similar in both groups. Temporary test stimulation was successful in 60 patients without HIRP (86%) and in 25 patients with HIRP (69 %) (p = 0.03). A permanent pulse generator was then implanted on these patients. After 1-year follow-up, the median FISI was reduced in patients without HIRP from 37 to 23 (p < 0.01). No significant change in FISI score was observed in patients with a HIRP (FISI, 38 to 34; p = 0.16). Quality of life (GIQLI) was only improved in patients without HIRP. A successful outcome per protocol was achieved in 31 patients without HIRP (52%) versus 4 patients with HIRP (16%) (p < 0.01).
Conclusion: The presence of a high-grade internal rectal prolapse has a detrimental effect on sacral neuromodulation for faecal incontinence.