Colonic volume in patients with functional constipation or irritable bowel syndrome determined by magnetic resonance imaging

BACKGROUND: Functional constipation (FC) and irritable bowel syndrome constipation type (IBS‐C) share many similarities, and it remains unknown whether they are distinct entities or part of the same spectrum of disease. Magnetic resonance imaging (MRI) allows quantification of intraluminal fecal volume. We hypothesized that colonic volumes of patients with FC would be larger than those of patients with IBS‐C, and that both patient groups would have larger colonic volumes than healthy controls (HC). METHODS: Based on validated questionnaires, three groups of participants were classified into FC (n = 13), IBS‐C (n = 10), and HC (n = 19). The colonic volume of each subject was determined by MRI. Stool consistency was described by the Bristol stool scale and colonic transit times were assessed with radiopaque makers. KEY RESULTS: Overall, total colonic volumes were different in the three groups, HC (median 629 ml, interquartile range (IQR)(562–868)), FC (864 ml, IQR(742–940)), and IBS‐C (520 ml IQR(489–593)) (p = 0.001). Patients with IBS‐C had lower colonic volumes than patients with FC (p = 0.001) and HC (p = 0.019), but there was no difference between FC and HC (p = 0.10). Stool consistency was similar in the two patient groups, but patients with FC had longer colonic transit time than those with IBS‐C (117.6 h versus 43.2 h, p = 0.019). CONCLUSION: Patients with IBS‐C have lower total colonic volumes and shorter colonic transit times than patients with FC. Future studies are needed to confirm that colonic volume allows objective distinction between the two conditions

Gastric transit and small intestinal transit time and motility assessed by a magnet tracking system

<p>Abstract</p> <p>Background</p> <p>Tracking an ingested magnet by the Magnet Tracking System MTS-1 (Motilis, Lausanne, Switzerland) is an easy and minimally-invasive method to assess gastrointestinal transit. The aim was to test the validity of MTS-1 for assessment of gastric transit time and small intestinal transit time, and to illustrate transit patterns detected by the system.</p> <p>Methods</p> <p>A small magnet was ingested and tracked by an external matrix of 16 magnetic field sensors (4 × 4) giving a position defined by 5 coordinates (position: <b>x, y, z, and angle: θ, ϕ)</b>. Eight healthy subjects were each investigated three times: (1) with a small magnet mounted on a capsule endoscope (PillCam); (2) with the magnet alone and the small intestine in the fasting state; and (3) with the magnet alone and the small intestine in the postprandial state.</p> <p>Results</p> <p>Experiment (1) showed good agreement and no systematic differences between MTS-1 and capsule endoscopy when assessing gastric transit (median difference 1 min; range: 0-6 min) and small intestinal transit time (median difference 0.5 min; range: 0-52 min). Comparing experiments (1) and (2) there were no systematic differences in gastric transit or small intestinal transit when using the magnet-PillCam unit and the much smaller magnetic pill. In experiments (2) and (3), short bursts of very fast movements lasting less than 5% of the time accounted for more than half the distance covered during the first two hours in the small intestine, irrespective of whether the small intestine was in the fasting or postprandial state. The mean contraction frequency in the small intestine was significantly lower in the fasting state than in the postprandial state (9.90 min^-1vs. 10.53 min^-1) (p = 0.03).</p> <p>Conclusion</p> <p>MTS-1 is reliable for determination of gastric transit and small intestinal transit time. It is possible to distinguish between the mean contraction frequency of small intestine in the fasting state and in the postprandial state.</p

Small intestinal transit in patients with liver cirrhosis and portal hypertension: a descriptive study

BACKGROUND: Gastrointestinal dysmotility may be involved in the development of bacterial translocation and infection in patients with liver cirrhosis. The aim of the present study was to describe gastric, small intestinal and colorectal motility and transit in patients with liver cirrhosis and portal hypertension using a magnet-based Motility Tracking System (MTS-1) and standard radiopaque markers. METHODS: We included 15 patients with liver cirrhosis (8 Child-Pugh A, 6 Child-Pugh B, and 1 Child-Pugh C) and portal hypertension (11 males, median age 54 years (range 38–73), median hepatic venous pressure gradient 18 mmHg (range 12–37)), and 18 healthy controls (8 males, median age 58 years (range 34–64)). The gastric emptying time and small intestinal motility were evaluated by MTS-1, and the total gastrointestinal transit time was assessed by radiopaque markers and abdominal radiographs. RESULTS: The velocity through the proximal small intestine was significantly higher in cirrhotic patients (median 1.27 metres (m)/hour, range 0.82–2.68) than in the healthy controls (median 1.00 m/hour, range 0.46–1.88) (p = 0.03). Likewise, the magnet travelled significantly longer in both fast (p = 0.04) and slow movements (p = 0.05) in the patient group. There was no significant difference in either gastric emptying time—23 minutes (range 5–131) in patients and 29 minutes (range 10.5–182) in healthy controls (p = 0.43)—or total gastrointestinal transit time—1.6 days (range 0.5–2.9) in patients and 2.0 days (range 1.0–3.9) in healthy controls (p = 0.33). No correlation was observed between the hepatic venous pressure gradient and the velocity of the magnet through the small intestine. CONCLUSION: Patients with liver cirrhosis and portal hypertension demonstrated faster-than-normal transit through the proximal small intestine. This may be due to an overactive bowel, as suggested by previous studies

Axial Movements and Length Changes of the Human Lower Esophageal Sphincter During Respiration and Distension-induced Secondary Peristalsis Using Functional Luminal Imaging Probe

Background/Aims: Efficient transport through the esophago-gastric junction (EGJ) requires synchronized circular and longitudinal muscle contraction of the esophagus including relaxation of the lower esophageal sphincter (LES). However, there is a scarcity of technology for measuring esophagus movements in the longitudinal (axial) direction. The aim of this study is to develop new analytical tools for dynamic evaluation of the length change and axial movement of the human LES based on the functional luminal imaging probe (FLIP) technology and to present normal signatures for the selected parameters.Methods: Six healthy volunteers without hiatal hernia were included. Data were analyzed from stepwise LES distensions at 20, 30, and 40 mL bag volumes. The bag pressure and the diameter change were used for motion analysis in the LES. The cyclic bag pressure frequency was used to distinguish dynamic changes of the LES induced by respiration and secondary peristalsis.Results: Cyclic fluctuations of the LES were evoked by respiration and isovolumetric distension, with phasic changes of bag pressure, diameter, length, and axial movement of the LES narrow zone. Compared to the respiration-induced LES fluctuations, peristaltic contractions increased the contraction pressure amplitude (P＜ 0.001), shortening (P＜ 0.001), axial movement (P＜ 0.001), and diameter change (P＜ 0.01) of the narrow zone. The length of the narrow zone shortened as function of the pressure increase.Conclusions: FLIP can be used for evaluation of dynamic length changes and axial movement of the human LES. The method may shed light on abnormal longitudinal muscle activity in esophageal disorders.</p