MR-enterography: role in the assessment of suspected anastomotic recurrence of Crohn disease after ileocolic resection.

PURPOSE: To determine the potential of magnetic resonance-enterography (MRE) in the assessment of the anastomotic status in patients with Crohn disease and prior ileocolic resection. METHODS: A total of 62 MRE examinations obtained in 52 patients with Crohn disease who had previously undergone ileocolic resection were retrospectively reviewed by two readers in consensus. MRE features (anastomotic wall thickening, wall stratification, wall enhancement pattern and degree, DWI signal intensity, ADC values, lymph nodes, comb sign and complications) were compared to clinical, endoscopic and histological findings that served as standard of reference. Sensitivity, specificity and accuracy of MRE were calculated. RESULTS: At univariate analysis, anastomotic wall thickening, anastomotic wall stratification, segmental wall enhancement, moderate wall enhancement, early and mucosal enhancement, and moderate/marked hyperintensity on diffusion-weighed imaging (DWI) were the most discriminative MRE features for differentiating between normal and abnormal anastomoses (p < 0.001 for all variables). Anastomotic wall thickening and segmental anastomotic wall enhancement were the two most sensitive and accurate MRE variables for the diagnosis of abnormal anastomosis with sensitivities of 82% (95% CI: 67-92%) and accuracies of 84% (95% CI: 72-92%). At univariate analysis, hyperintensity on DWI of the anastomotic site was the most sensitive finding for distinguishing between inflammatory recurrence and fibrostenosis (sensitivity, 89%; 95% CI: 67-99%). CONCLUSIONS: MRE provides objective and relatively specific morphological criteria that help detect abnormal ileocolic anastomosis, but performances are lower when differentiating between inflammatory recurrence and fibrostenosis. DWI may be useful in identifying pathologic anastomosis and, in particular, in distinguishing between inflammatory recurrence and fibrostenosis.

Liver Malignancies Treated With Intra-Arterial Therapy: Assessment of Early Response as Quantified by Volumetric Enhancement Using Gadoxetate Disodium.

OBJECTIVE: The aim of the study was to evaluate the value of volumetric contrast-enhanced magnetic resonance imaging (MRI) using gadoxetate disodium in early assessment of treatment response after intra-arterial therapy (IAT). MATERIALS AND METHODS: This prospective study included 21 patients (32 malignant lesions) who underwent MRI using gadoxetate disodium before and early after IAT. Two reviewers reported response by anatomic criteria including Response Evaluation Criteria in Solid Tumor (RECIST), Modified RECIST (mRECIST), and European Association for the Study of Liver Disease and functional criteria including volumetric enhancement in hepatic arterial phase and portal venous phase. Treatment end point was RECIST at 6 months. A 2-sample paired t test was used to compare the mean changes after IAT. A P value of less than 0.05 was considered statistically significant. RESULTS: Responders by RECIST at 6 months did not fulfill partial response by conventional criteria at 1 month, except for mRECIST by reader 2. The mRECIST and European Association for the Study of Liver Disease could not be assessed in a total of 4 and 3 lesions for readers 1 and 2, respectively. However, volumetric measurements were obtained in all lesions and the changes were statistically significant at 1 month for hepatic arterial phase (P = 0.02 and P = 0.008) and portal venous phase (P < 0.0001 and P < 0.0001), as assessed by both readers, respectively. CONCLUSIONS: Volumetric contrast-enhanced MRI using gadoxetate disodium may be a helpful tool to evaluate early treatment response after IAT in malignant liver tumors.