Quantified Terminal Ileal Motility during MR Enterography as a Biomarker of Crohn Disease Activity: Prospective Multi-Institution Study.

Purpose To evaluate the accuracy of MRI-quantified small bowel motility for Crohn disease activity against endoscopic and histopathologic reference standards. Materials and Methods For this prospective study, 82 participants (median age, 31 years; range, 16 to 70 years; 42 males [median age, 31 years; range, 17 to 70 years] and 40 females [median age, 31 years; range, 16 to 63 years) underwent colonoscopy and MR enterography within 14 days (from October 2011 to March 2014) at two centers. The Crohn disease endoscopic index of severity (CDEIS), histopathologic activity score (endoscopic biopsy acute histologic inflammatory score [EAIS]), and MR index of activity (MaRIA) were scored in the terminal ileum.

Long-Term Performance of Readers Trained in Grading Crohn Disease Activity Using MRI.

Rationale And Objectives: We aim to evaluate the long-term performance of readers who had participated in previous magnetic resonance imaging (MRI) reader training in grading Crohn disease activity.

Materials And Methods: Fourteen readers (8 women; 12 radiologists, 2 residents; mean age 40; range 31-59), who had participated in a previous MRI reader training, participated in a follow-up evaluation after a mean interval of 29 months (range 25-34 months). Follow-up evaluation comprised 25 MRI cases of suspected or known Crohn disease patients with direct feedback; cases were identical to the evaluation set used in the initial reader training (of which readers were unaware).

Image Registration Based on Autocorrelation of Local Structure.

Registration of images in the presence of intra-image signal fluctuations is a challenging task. The definition of an appropriate objective function measuring the similarity between the images is crucial for accurate registration. This paper introduces an objective function that embeds local phase features derived from the monogenic signal in the modality independent neighborhood descriptor (MIND).

Semi-supervised and active learning for automatic segmentation of Crohn's disease.

Our proposed method combines semi supervised learning (SSL) and active learning (AL) for automatic detection and segmentation of Crohn's disease (CD) from abdominal magnetic resonance (MR) images. Random forest (RF) classifiers are used due to fast SSL classification and capacity to interpret learned knowledge. Query samples for AL are selected by a novel information density weighted approach using context information, semantic knowledge and labeling uncertainty.

Training readers to improve their accuracy in grading Crohn's disease activity on MRI.

Objectives: To prospectively evaluate if training with direct feedback improves grading accuracy of inexperienced readers for Crohn's disease activity on magnetic resonance imaging (MRI).

Methods: Thirty-one inexperienced readers assessed 25 cases as a baseline set. Subsequently, all readers received training and assessed 100 cases with direct feedback per case, randomly assigned to four sets of 25 cases.

Grading Crohn disease activity with MRI: interobserver variability of MRI features, MRI scoring of severity, and correlation with Crohn disease endoscopic index of severity.

Objective: The purpose of this article is to assess the interobserver variability for scoring MRI features of Crohn disease activity and to correlate two MRI scoring systems to the Crohn disease endoscopic index of severity (CDEIS).

Materials And Methods: Thirty-three consecutive patients with Crohn disease undergoing 3-T MRI examinations (T1-weighted with IV contrast medium administration and T2-weighted sequences) and ileocolonoscopy within 1 month were independently evaluated by four readers. Seventeen MRI features were recorded in 143 bowel segments and were used to calculate the MR index of activity and the Crohn disease MRI index (CDMI) score.

Automatic Detection and Segmentation of Crohn's Disease Tissues From Abdominal MRI.

We propose an information processing pipeline for segmenting parts of the bowel in abdominal magnetic resonance images that are affected with Crohn's disease. Given a magnetic resonance imaging test volume, it is first oversegmented into supervoxels and each supervoxel is analyzed to detect presence of Crohn's disease using random forest (RF) classifiers. The supervoxels identified as containing diseased tissues define the volume of interest (VOI).

Evaluation of conventional, dynamic contrast enhanced and diffusion weighted MRI for quantitative Crohn's disease assessment with histopathology of surgical specimens.

Objectives: To prospectively compare conventional MRI sequences, dynamic contrast enhanced (DCE) MRI and diffusion weighted imaging (DWI) with histopathology of surgical specimens in Crohn's disease.

Methods: 3-T MR enterography was performed in consecutive Crohn's disease patients scheduled for surgery within 4 weeks. One to four sections of interest per patient were chosen for analysis.

Serial magnetic resonance imaging for monitoring medical therapy effects in Crohn's disease.

Background: Tumor necrosis factor (TNF) antagonists can induce mucosal healing in patients with Crohn's disease (CD), but the effects on transmural inflammation and stenotic lesions are largely unknown.

Methods: We performed a retrospective study in 50 patients (54% female, median age 37 yr) with CD who had undergone serial magnetic resonance imaging (MRI) examinations while receiving infliximab or adalimumab. Patients were grouped as clinical responders or nonresponders based on physician's assessment, laboratory, and endoscopic appearance.

A multi-centre randomised double-blind placebo-controlled trial to evaluate the value of a single bolus intravenous alfentanil in CT colonography.

Background: Pain is common during colonic insufflation required for CT colonography. We therefore evaluate whether a single intravenous alfentanil bolus has a clinically relevant analgesic effect compared with placebo in patients undergoing CT colonography.

Methods: A prospective multi-centre randomised double-blind placebo-controlled trial was performed in patients scheduled for elective CT colonography.

A supervised learning approach for Crohn's disease detection using higher-order image statistics and a novel shape asymmetry measure.

Increasing incidence of Crohn's disease (CD) in the Western world has made its accurate diagnosis an important medical challenge. The current reference standard for diagnosis, colonoscopy, is time-consuming and invasive while magnetic resonance imaging (MRI) has emerged as the preferred noninvasive procedure over colonoscopy. Current MRI approaches assess rate of contrast enhancement and bowel wall thickness, and rely on extensive manual segmentation for accurate analysis.

Computational modeling for assessment of IBD: to be or not to be?

The grading of inflammatory bowel disease (IBD) severity is important to determine the proper treatment strategy and to quantify the response to treatment. Traditionally, ileocolonoscopy is considered the reference standard for assessment of IBD. However, the procedure is invasive and requires extensive bowel preparation.

[A man who became acutely agitated after injection of contrast].

A 63-year-old man attended the emergency room with lower back pain. An abdominal CT scan was scheduled. However, after intravenous injection of contrast, the patient became acutely agitated and his tension dropped.

T2* measurement of the knee articular cartilage in osteoarthritis at 3T.

Purpose: To measure reproducibility, longitudinal and cross-sectional differences in T2* maps at 3 Tesla (T) in the articular cartilage of the knee in subjects with osteoarthritis (OA) and healthy matched controls.

Materials And Methods: MRI data and standing radiographs were acquired from 33 subjects with OA and 21 healthy controls matched for age and gender. Reproducibility was determined by two sessions in the same day, while longitudinal and cross-sectional group differences used visits at baseline, 3 and 6 months.

A computer-assisted model for detection of MRI signs of Crohn's disease activity: future or fiction?

Magnetic resonance imaging is increasingly used for abdominal evaluation and is more and more considered as the optimal imaging technique for detection of mural inflammation in patients with Crohn's disease. Grading the disease activity is important in daily clinical practice to monitor the medical treatment and is assessed by evaluating different magnetic resonance imaging features. Unfortunately, only moderate interobserver agreement is reported for most of the subjective features and should be improved.