Prospective evaluation of free-breathing diffusion-weighted imaging for the detection of inflammatory bowel disease with MR enterography in childhood population

International audienceObjective: To evaluate prospectively the performance of diffusion-weighted imaging (DWI) for the detection of active lesions on MR enterography (MRE) in children with inflammatory bowel disease (IBD).Methods: MRE of 48 children (mean age 13 years) with suspected or known IBD were blindly analysed by 2 independent readers for the presence of active lesions. Two sets of imaging including DWI and gadolinium-enhanced imaging (GEI) were reviewed. A reader consensus was obtained. The gold standard was histopathological findings. In patient-level analysis and segment-level analysis, sensitivity and specificity were calculated for DWI and GEI and compared using McNemar's test or logistic random-effects models.Results: At least 1 active lesion was confirmed in 42 (87.5%) children. Sensitivity and specificity for the detection of at least one lesion were 88.1% (95% CI, 74.3-96.1) and 83.3% (95% CI, 35.9-99.6), respectively, for DWI and 66.7% (95% CI, 50.4-80.4) and 83.3% (95% CI, 35.9-99.6), respectively, for GEI. In segment-level analysis, sensitivity and specificity for the detection of specific segment lesions were 62.5% (95% CI, 48.1-75) and 97.1% (95% CI, 93.5-98.7), respectively, for DWI and 45.7% (95% CI, 30.8-61.3) and 98.2% (95% CI, 95.3-99.4), respectively, for GEI. The sensitivity of DWI was significantly better than that of GEI per patient (p = 0.004) and per segment (p = 0.028).Conclusion: DWI demonstrates better performance than GEI for the detection of active lesions in children with IBD.Advances in knowledge: Examination with no intravenous injection-DWI can replace T1 weighted images when paediatric patients are screened with MRE for IBD. Examination performed in free breathing is better tolerated by children

Asymptomatic Progressive Multifocal Leukoencephalopathy Associated with Natalizumab: Diagnostic Precision with MR Imaging

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