Body surface colonic mapping detects meal and bisacodyl-induced colonic motility in patients with chronic constipation

OBJECTIVES: Chronic constipation is highly prevalent, and cases refractory to medical treatment are particularly challenging to manage. High-resolution colonic manometry (HRM) is used to further evaluate these patients to identify cases of intrinsic motor dysfunction (underlying myopathy or neuropathy) based on deficient or impaired increases in colonic motor patterns evoked by meal and bisacodyl stimuli. However, HRM is invasive and resource-intensive, limiting uptake and clinical utility. The aim of this study was to validate Body Surface Colonic Mapping (BSCM), a non-invasive cutaneous electrical recording technique, as a viable clinical alternative. METHODS: Simultaneous recordings from HRM (36-channel) and BSCM (8x8 electrode array) were performed in 10 patients with refractory chronic constipation. Patients recorded abdominal symptom scores for the duration of the recording. Motility was assessed during meal and bisacodyl challenges. We optimized BSCM signal processing to detect high-amplitude propagating contractions (HAPCs) evoked by bisacodyl. Analysis included time-frequency quantification of motility indices and blinded visual assessment by domain experts to classify the presence or absence of motor responses. RESULTS: BSCM motility indices showed strong correlation with HRM for both meal (r = 0.86) and bisacodyl (r = 0.69) responses. Expert visual analysis yielded concordant classification between BSCM and HRM in the majority (87.5 ± 9.6%) of cases. Furthermore, BSCM identified distinct, patient-specific symptom-motility associations during the meal response. DISCUSSION: BSCM accurately detects meal and bisacodyl-induced increases in colonic motility with high fidelity to invasive HRM. BSCM could be applied in larger cohort studies to elucidate symptom-motility associations and guide personalized management in refractory chronic constipation.