Assessment of Small Bowel Motility in Patients With Chronic Intestinal Pseudo-Obstruction Using Cine-MRI

OBJECTIVES : Chronic intestinal pseudo-obstruction (CIPO) is a rare, serious motility disorder, with life-threatening complications over time. However, lack of an established, non-invasive diagnostic method has caused delays in the diagnosis of this intractable disease. Cine-magnetic resonance imaging (MRI) is an emerging technique, with a potential to evaluate the motility of the entire bowel. We compared small bowel motility in healthy volunteers, patients with irritable bowel syndrome (IBS), and those with CIPO, using cine-MRI, and evaluated the usefulness of cine-MRI as a novel diagnostic method for CIPO. METHODS: Twelve healthy volunteers, IBS patients, and CIPO patients prospectively underwent cine-MRI at 1.5 T. Luminal diameter, contraction ratio, and contraction cycle were measured and compared between the groups. RESULTS: Cine-MRI provided sufficient dynamic images to assess the motility of the entire small bowel. Luminal diameter (mean +/- s.d.) in CIPO patients was significantly higher than that in healthy volunteers and IBS patients (43.4 +/- 14.1, 11.1 +/- 1.5, and 10.9 +/- 1.9 mm, respectively), and contraction ratio was significantly lower in CIPO patients than that in healthy volunteers and IBS patients (17.1 +/- 11.0%, 73.0 +/- 9.3%, and 74.6 +/- 9.4%, respectively). No significant differences were observed in the contraction cycle. CONCLUSIONS: This study is the first to assess the clinical utility of cine-MRI in CIPO patients. Cine-MRI clearly detected contractility impairments in CIPO patients. Cine-MRI is noninvasive, radiation-free, and can directly evaluate the entire small bowel peristalsis, and can detect the affected loops at a glance; therefore, it might be extremely useful for the diagnosis and follow-up of CIPO patients in clinical practice.