More movement with evaluating colonic transit in humans

Abstract

Background Colonic functions (ie, absorption of fluids and electrolytes, digestion of selected nutrients, harbor for microbes, and elimination of excreta) necessitate complex patterns of storage and transit. Indeed, colonic transit accounts for a major part of the mouth‐to‐anus transit time. Colonic transit assessments are useful for understanding the pathophysiology of disease, the pharmacodynamic effects of new medications and to diagnose slow transit constipation. Currently, radiopaque markers, scintigraphy, and a colonic pH‐pressure capsule are used to measure overall colonic transit. Radioopaque markers, scintigraphy, and the electromagnetic capsule, which is a newer technique, also evaluate regional colonic transit. The pH‐pressure capsule also measures colonic pressures. Magnetic resonance imaging and a radio‐frequency identification‐based device are evolving methods for assessing colonic transit. Purpose This mini‐review, which accompanies a study evaluating the assessment of colon transit with the electromagnetic capsule, evaluates and compares existing and evolving methods for evaluating colonic transit in humans (Neurogastroenterol Motil. 2018; in press). In addition to overall and regional colonic transit, the electromagnetic capsule evaluates colonic motor patterns without radiation exposure. These patterns are summarized by analyzing the characteristics (ie, distance and velocity) of discrete antegrade and retrograde capsule movements as they travel in the colon. However, the electromagnetic capsule does not measure pressure or colonic wall movement (ie, contractions). The motor patterns identified by this capsule should be compared with motor patterns identified with manometry. The next challenge is to harness different techniques to evaluate the relationships between colonic pressures and transit or, even better, the trifecta of colonic contractions, pressure events, and transit.

Prediction of Inadequate Bowel Preparation Using Total and Segmental Colon Transit Time in Patients with Chronic Constipation: Some Different Outcomes

“…For instance, Chan and colleagues [13] demonstrated that the mean total CTT in healthy Chinese adults was 24.5 h, which was very similar to the 23.08 h we observed in the HC group. Though a universal standard for CTT has not been established, 30 h is a commonly used benchmark for the standard colon transit time [11, 13, 14].…”

“…A single capsule containing 24 radio-opaque markers (Sitzmarks, Konsyl Pharmaceutical, TX, USA) was taken once per day for three consecutive days at 8 am. The protocol was similar to that described by Bharucha and some authors and colleagues [11]. Simple abdominal radiographs were taken at 8 am on day four of the study.…”

High-resolution colonic manometry and its clinical application in patients with colonic dysmotility: A review

“…The frequency of 3 times per minute accounts for more than 80% of the total rhythmic frequency. This rhythm pattern commonly occurs in the junction area between the sigmoid and rectum, where there is no functional sphincter according to some studies[22]. The absence of a functional sphincter can lead to dysfunction in the defecation process, which can explain the pathological mechanism of some functional constipation disorders[23,24].…”

On the nature of high-amplitude propagating pressure waves in the human colon

“…This coordinated spatiotemporal pattern has been suggested to play an important role in the shifting of colonic content in the rectal direction to prepare for defecation, as most individual HAPWs do not span the entire colon (9). The innervation of the colon also shows regional differences (9,58), and functional differences related to transit and storage are well documented (5,7,41). There have also been indications in the pediatric literature that HAPWs are not normal unless they span the entire colon (47), which makes it important to study regional HAPWs.…”