Endorectal Ultrasound and Real-Time Elastography in Patients with fecal Incontinence Following Anorectal Surgery: A Prospective Comparison Evaluating Short- and Long-Term Outcomes in Irradiated and Non-Irradiated Patients

Background and Aims: Transanal real-time elastography (RTE) was demonstrated to yield valuable information regarding elastic properties of the anal sphincter in patients with fecal incontinence. We studied the role of RTE findings as a risk factor for the outcome of patients with fecal incontinence following anorectal surgery in irradiated and non-irradiated individuals and compared these observations with conventional B-mode/color Doppler EUS. Patients and Methods: 90 patients with postsurgical fecal incontinence were included in this prospective monocentric study. Baseline and follow-up (after 3 weeks and 1 year) assessment included an incontinence severity score questionnaire, rectal manometry, B-mode/color Doppler EUS and RTE with quantitation of the sphincter elastograms. Results: 81 patients could be finally assessed, in 24 patients (29.6%) a pathological elastogram with predominantly hard elements was found; logistic regression analysis revealed no significant association with the short- and long-term clinical outcome nor were any differences seen between irradiated and non-irradiated patients. Defined sphincter defects as seen with conventional EUS were significanntly associated with a worse short- and longterm outcome: odds ratio ORshort-term: 1.414 (1.107 - 1.807, p = 0.0101); ORlong-term: 1.675 (95% CI: 1.133 - 2.477; p = 0.0294). Submucosal thickening and hypervascularization were found more frequently in the irradiated group (p < 0.01). Conclusion: RTE with quantitation of sphincter elastic properties yields no further diagnostic and prognostic information compared to conventional EUS in irradiated and non-irradiated patients and, therefore, cannot be regarded as a new tool in the assessment of those patients. Our data further confirm the view that defined sphincter defects may be a major risk factor for an unfavorable outcome.