Cortical evoked potentials in response to rapid balloon distension of the rectum and anal canal. Issue 6 (20th April 2014)

• Record Type: Journal Article
• Authors: Haas, S.; Brock, C.; Krogh, K.; Gram, M.; Nissen, T. D.; Lundby, L.; Laurberg, S.; Drewes, A. M.
• Is Part Of: Neurogastroenterology & motility. Volume 26:Issue 6(2014:Jun.)
• Page Start: 862
• Page End: 873
• Publication Date: 2014-04-20
• Subjects: Gastrointestinal system -- Motility -- Periodicals; Gastrointestinal system -- Innervation -- Periodicals; 616.33
• DOI: 10.1111/nmo.12341
• Languages: English
• ISSNs: 1350-1925

Abstract

<abstract abstract-type="main" id="nmo12341-abs-0001"> <title>Abstract</title> <sec id="nmo12341-sec-0001" sec-type="section"> <title>Background</title> <p>Neurophysiological evaluation of anorectal sensory function is hampered by a paucity of methods. Rapid balloon distension (RBD) has been introduced to describe the cerebral response to rectal distension, but it has not successfully been applied to the anal canal.</p> </sec> <sec id="nmo12341-sec-0002" sec-type="section"> <title>Methods</title> <p>Nineteen healthy women received 30 RBDs in the rectum and the anal canal at intensities corresponding to sensory and unpleasantness thresholds, and response was recorded as cortical evoked potentials (CEPs) in 64‐channels. The anal canal stimulations at unpleasantness level were repeated after 4 min to test the within‐day reproducibility. CEPs were averaged, and to overcome latency variation related to jitter the spectral content of single sweeps was also computed.</p> </sec> <sec id="nmo12341-sec-0003" sec-type="section"> <title>Key Results</title> <p>Repeated stimulation of the anal canal generated CEPs with similar latencies but smaller amplitudes compared to those from the rectum. Due to latency jitter, reproducibility of averaged CEPs was lower than what was found in the rectum. The most reproducible feature was N2P2 peak‐to‐peak amplitude with intra‐class correlation coefficient (ICC) of 0.7 and coefficient of variation (CV) of 18%. Spectral content of the single sweeps showed reproducibility with ICCs for all bands >0.8 and corresponding CVs <7%.</p> </sec> <sec id="nmo12341-sec-0004" sec-type="section"> <title>Conclusions & Inferences</title> <p>Cortical potentials evoked from the anal canal are challenged by latency jitter likely related to variability in muscle tone due to the distensions. Using single‐sweep analysis, anal CEPs proved to be reproducible and should be used in future evaluation of the anal function.</p> </sec> </abstract>