Characterization of Patients With Obstructed Defecation and Slow Transit Constipation With a Simulated Stool

Abstract

INTRODUCTION: Defecatory disorders including obstructed defecation (OD) are currently diagnosed using specialized investigations including anorectal manometry and the balloon expulsion test. Recently, we developed a simulated stool named Fecobionics that provides a novel type of pressure measurements and analysis. The aim was to study OD phenotypes compared with slow transit constipation (STC) patients and normal subjects (NS). METHODS: Fecobionics expulsion parameters were assessed in an interventional study design. The Fecobionics device contained pressure sensors at the front, rear, and inside a bag. All constipation patients had colon transit study, defecography, anorectal manometry, and balloon expulsion test performed. The Fecobionics bag was distended in the rectum until desire-to-defecate in 26 OD compared with 8 STC patients and 10 NS. Rear-front pressures (preload-afterload parameters) and defecation indices (DIs) were compared between groups. RESULTS: The Wexner constipation scoring system score was 13.8 ± 0.9 and 14.6 ± 1.5 in the OD and STC patients (P > 0.5). The median desire-to-defecate volume was 80 (quartiles 56–80), 60 (54–80), and 45 (23–60) mL in OD, STC, and NS, respectively (P < 0.01). The median expulsion duration was 37 (quartiles 15–120), 6 (3–11), and 11 (8–11) seconds for the 3 groups (P < 0.03). Fecobionics rear-front pressure diagrams demonstrated clockwise loops with distinct phenotype differences between OD and the other groups. Most DIs differed between OD and the other groups, especially those based on the anal afterload reflecting the nature of OD constipation. Several OD subtypes were identified. DISCUSSION: Fecobionics obtained novel pressure phenotypes in OD patients. DIs showed pronounced differences between groups. Larger studies are needed on OD subtyping.

Fecobionics Evaluation of Biofeedback Therapy in Patients With Fecal Incontinence

“…Technological validation and data on normal subjects have been reported previously (11–13,30,31). Small-scale clinical studies have been performed in patients with FI, constipation, and low anterior resection syndrome (14–17). This study is the first exploratory study for monitoring the effect of BFT in FI patients and will serve as a reference for future larger scale clinical studies with further optimized technologies.…”

“…The rear-front (preload-afterload) diagrams were plotted (11,13,23,24). These diagrams constitute a useful way to display data (14)(15)(16)(17). The preload that must exceed the afterload before evacuation can take place because feces movement cannot occur against an anorectal pressure gradient.…”

“…Reference data were obtained with ARM-BET, although the main purpose of this study was not comparative. Previous studies have shown marked differences between Fecobionics and ARM-BET data (13)(14)(15)(16).…”

“…Fecobionics is a defecatory test measuring multiple physiological variables during evacuation of the device. Technological validation (11) and studies on normal subjects and patients with FI, obstructed defecation, and low anterior resection syndrome have been published (12–17). In agreement with other technologies, simple measures obtained by Fecobionics did not show differences between FI patients and normal subjects (15).…”

“…In agreement with other technologies, simple measures obtained by Fecobionics did not show differences between FI patients and normal subjects (15). However, axial pressure signatures (12), preload-afterload analysis, and distensibility indices (DIs) by Fecobionics provided useful end points for FI and constipation (11–17).…”