Measurement of MRI enhancement kinetics for evaluation of inflammatory activity in Crohn's disease

PurposeTo investigate the feasibility of determining local inflammatory activity of Crohn's disease by measurement of bowel wall perfusion kinetics using contrast-enhanced magnetic resonance imaging (MRI).Material and methodsTwenty-six patients with histologically proven Crohn's disease who underwent magnetic resonance (MR) enteroclysis at 1.5 T were included in this retrospective study. Over 109 s, 150 images were acquired with a fat-saturated coronal T1-weighted 2D gradient echo sequence (TR, 9 ms; TE, 1.5 ms) during intravenous contrast administration by means of a pump (Magnevist, 0.2 ml/kg, flow 3 ml/s). On each image, signal intensity was measured in a region of interest placed in an area of maximum thickening of the inflamed bowel wall. Enhancement kinetics were correlated with the endoscopically determined severity of inflammatory activity (on a scale of 0–3).ResultsThe slope of the contrast enhancement curve significantly correlated with local inflammatory activity determined by endoscopy (R=0.594, P=.007). No significant correlation was found for area under the curve and peak maximum (R=0.411, P=.08 and R=0.334, P=.15, respectively).ConclusionDetermination of the perfusion kinetics of the bowel wall by MRI enables quantitative evaluation of local inflammatory activity in patients with Crohn's disease.