ABSTRACT
[Objective] To analyze the image findings of MR enterography (MRE) and diffusion weighted imaging (DWI) in Crohn disease (CD) and to discuss the diagnostic value of MRI for evaluating the activity of CD.[Methods] 26 patients proved by clinical,imaging and pathological data were enrolled in this study.The intra-/extra-intestinal image features of CD were retrospectively analyzed,and the intestinal lesions were evaluated by MRE+DWI scoring system.The differences in image features of active and inactive CD were compared.[Results] 26 bowel segments were evaluated and included active (n =20) and inactive CD (n =6).The intestinal performance of CD included wall thickening,T2WI hyperintensity and hyperenhancement.The pathological changes of active CD were more serious when comparing with that of inactive CD.DWI showed hyperintensity in the affected bowel wall.ADC of active C D [(0.9 ± 0.2) × 10-3 mm2/s] was significantly lower than that of inactive CD [(1.5 ± 0.4)× 10-3 mm2/s] (P ＜ 0.001).Extra-enteric performance of active CD included comb sign,lymphadenectasis of mesentery,mesenteric exudation,fistula and abdominal abscess.[Conclusion] MRE combined with DWI can accurately assess CD activity and diagnose extra-enteric complications.
ABSTRACT
[Objective]To explore the efficacy of T2* mapping for evaluating inflammatory activity in the patients with Crohn disease(CD).[Methods]A total of 98 CD patients underwent MR enterographywith T2*WI. T2* values were measured by put-ting regions of interest on the thickening bowel wall on T2*mapping. The activity of bowel segment was scored by magnetic resonance index of activity(MaRIA),to analyze the relationship between T2*values with CD activity.[Results]A total of 160 bowel segments were evaluated and includedinactive(MaRIA<7,n=26),mild(7≤MaRIA<11,n=23),and moderately-severe(MaRIA≥11, n = 111)active lesions. The differences in T2* values amongthese three groups were significant(all P < 0.05). T2* values of 160 bowel segments correlatedclosely withMaRIA(r=0.743,P<0.05). High accuracy of T2*values was shown for differentiating inac-tive from active CD(AUC=0.877)anddifferentiating inactive-mild from moderate-severe CD(AUC=0.848). The threshold T2*value of 20 ms allowed differentiation of mild from moderate-severe CD with74.5%sensitivity and 84%specificity.[Conclusions]T2*values, as thequantitative indexof T2*mapping,correlate well with CD activity and showsatisfiedefficacy for diagnosing inflammatoryactivity.
ABSTRACT
Today, cross-sectional imaging modalities, such as computed tomography enterography (CTE) and magnetic resonance enterography (MRE), are particularly suited to evaluate small bowel diseases, especially Crohn's disease (CD). It is well known that CTE/MRE can provide excellent assessment of disease activity as well as the macroscopic features, extramural abnormalities, and complications of the small intestine in patients with CD. In general, CTE is considered as the first-line modality for the evaluation of suspected inflammatory bowel disease and for long-term assessment or follow-up of these patients. Because of the advantage of lack of radiation, MRE is being used more frequently, especially in children or young patients with CD.