MR and Ultrasound for Liver Fat Assessment in Children: Techniques and Supporting Evidence.

Hepatic steatosis is a common imaging finding that can be a sign of chronic liver disease, most often associated with metabolic dysfunction-associated steatotic liver disease (MASLD). Imaging techniques for evaluating steatosis range from basic qualitative assessments to advanced and highly accurate quantitative metrics. Among these, MRI-based proton density fat fraction (PDFF) is widely regarded as a reliable and precise imaging biomarker for quantifying liver steatosis.

Comparison of volumetric and linear measurements of intestinal inflammation and treatment response in children with newly diagnosed ileal Crohn disease.

Objectives: To compare the responsiveness of linear and volumetric assessments of intestinal inflammation in children with newly diagnosed ileal Crohn disease (CD) into treatment.

Materials And Methods: Twenty children with ileal CD (8 girls; mean age = 14.0 years) between May 2019 and April 2021 underwent research MRI at three time points-diagnosis, 6 weeks, and 6 months into treatment.

Magnetic resonance cholangiopancreatography for suspected cholangiopathy in children and young adults: a multi-reader agreement study.

Background: Magnetic resonance cholangiopancreatography (MRCP) is used to diagnose and monitor primary sclerosing cholangitis (PSC).

Objective: To assess inter-reader agreement for the diagnosis of PSC/autoimmune sclerosing cholangitis (ASC) and for individual MRCP features of cholangiopathy in a pediatric sample.

Materials And Methods: This was a retrospective, IRB-approved study that included MRCP examinations from patients <21 years old with known or suspected cholangiopathy.

Liver fibrosis classification on trichrome histology slides using weakly supervised learning in children and young adults.

Background: Traditional liver fibrosis staging via percutaneous biopsy suffers from sampling bias and variable inter-pathologist agreement, highlighting the need for more objective techniques. Deep learning models for disease staging from medical images have shown potential to decrease diagnostic variability, with recent weakly supervised learning strategies showing promising results even with limited manual annotation.

Purpose: To study the clustering-constrained attention multiple instance learning (CLAM) approach for staging liver fibrosis on trichrome whole slide images (WSIs) of children and young adults.

T1 signal intensity ratio variability based on sampling strategies in the pancreas of children and young adults.

Purpose: T1-weighted signal intensity ratios (SIR) comparing pancreas to spleen (SIRps) or muscle (SIRpm) can semiquantitatively assess T1 signal change associated with pancreatitis. However, there is no standardized methodology for generating these ratios. We set out to determine the impact of MRI sequence as well as region of interest (ROI) location, shape, and size on T1 SIR.

Circulating and Magnetic Resonance Imaging Biomarkers of Intestinal Fibrosis in Small Bowel Crohn's Disease.

Background: We previously identified circulating and MRI biomarkers associated with the surgical management of Crohn's disease (CD). Here we tested associations between these biomarkers and ileal resection inflammation and collagen content.

Methods: Fifty CD patients undergoing ileal resection were prospectively enrolled at 4 centers.

Multi-site, multi-vendor development and validation of a deep learning model for liver stiffness prediction using abdominal biparametric MRI.

Background: Chronic liver disease (CLD) is a substantial cause of morbidity and mortality worldwide. Liver stiffness, as measured by MR elastography (MRE), is well-accepted as a surrogate marker of liver fibrosis.

Purpose: To develop and validate deep learning (DL) models for predicting MRE-derived liver stiffness using routine clinical non-contrast abdominal T1-weighted (T1w) and T2-weighted (T2w) data from multiple institutions/system manufacturers in pediatric and adult patients.

Practical approach to quantitative liver and pancreas MRI in children.

Quantitative abdominal magnetic resonance imaging (MRI) offers non-invasive, objective assessment of diseases in the liver, pancreas, and other organs and is increasingly being used in the pediatric population. Certain quantitative MRI techniques, such as liver proton density fat fraction (PDFF), R2* mapping, and MR elastography, are already in wide clinical use. Other techniques, such as liver T1 mapping and pancreas quantitative imaging methods, are emerging and show promise for enhancing diagnostic sensitivity and treatment monitoring.

Multi-band vs. conventional diffusion-weighted MRI of the abdomen in children and young adults.

Objectives: Implementation of diffusion-weighted imaging (DWI) for abdominal imaging in children has challenges due to motion artifacts exacerbated by long acquisition times. We aimed to compare acquisition time and image quality between conventional DWI and multi-band (MB) DWI of the liver in children and young adults.

Methods: Clinical MRI exams from May 2023 to January 2024 were reviewed, including four DWI sequences: respiratory-triggered (RTr, clinical standard), free-breathing (FB), MB-DWI with shift factor 1 (MBsf1), and MB-DWI with shift factor 2 (MBsf2).

Development and Validation of a Modality-Invariant 3D Swin U-Net Transformer for Liver and Spleen Segmentation on Multi-Site Clinical Bi-parametric MR Images.

To develop and validate a modality-invariant Swin U-Net Transformer (UNETR) deep learning model for liver and spleen segmentation on abdominal T1-weighted (T1w) or T2-weighted (T2w) MR images from multiple institutions for pediatric and adult patients with known or suspected chronic liver diseases. In this IRB-approved retrospective study, clinical abdominal axial T1w and T2w MR images from pediatric and adult patients were retrieved from four study sites, including Cincinnati Children's Hospital Medical Center (CCHMC), New York University (NYU), University of Wisconsin (UW) and University of Michigan / Michigan Medicine (UM). The whole liver and spleen were manually delineated as the ground truth masks.

State of original pediatric radiology research in major radiology journals other than Pediatric Radiology.

Background: Understanding distribution of published pediatric imaging research in radiology journals is relevant to understanding the state of research in the field.

Objective: To understand the current state of published original pediatric imaging research in major clinical radiology journals other than Pediatric Radiology.

Materials And Methods: We reviewed clinical imaging journals from among the top 20 radiology journals according to the Google Scholar h5-index as of June 2024.

Longitudinal evaluation of pediatric and young adult metabolic dysfunction-associated steatotic liver disease defined by MR elastography.

Objectives: To inform clinical monitoring of children and young adults with metabolic dysfunction-associated steatotic liver disease (MASLD) by characterizing the real-world natural history of MASLD and identifying baseline predictors of liver disease progression.

Materials And Methods: This retrospective study included consecutive patients ages < 23 years with MASLD who underwent serial MR elastography (MRE) and/or MR fat fraction (FF) examinations between 09/2009 and 11/2022. Outcomes of MASLD were defined based on maximum ratio values.

Joint self-supervised and supervised contrastive learning for multimodal MRI data: Towards predicting abnormal neurodevelopment.

The integration of different imaging modalities, such as structural, diffusion tensor, and functional magnetic resonance imaging, with deep learning models has yielded promising outcomes in discerning phenotypic characteristics and enhancing disease diagnosis. The development of such a technique hinges on the efficient fusion of heterogeneous multimodal features, which initially reside within distinct representation spaces. Naively fusing the multimodal features does not adequately capture the complementary information and could even produce redundancy.

MR enterography radiologic ulcers in newly diagnosed ileal Crohn disease in children: frequency, inter-radiologist agreement, and clinical correlation.

Background: Radiologic ulcers are increasingly recognized as an imaging finding of bowel wall active inflammation in Crohn disease (CD).

Objective: To determine the frequency of ulcers at MR enterography (MRE) in children with newly diagnosed ileal CD, assess agreement between radiologists, and evaluate if their presence correlates with other imaging and clinical features of intestinal active inflammation.

Materials And Methods: This retrospective study included 108 consecutive pediatric patients (ages 6-18 years) with newly diagnosed ileal CD that underwent clinical MRE prior to treatment initiation between January 2021 and December 2022.

Simultaneous Multiparameter Mapping of the Liver in a Single Breath-Hold or Respiratory-Triggered Acquisition Using Multi-Inversion Spin and Gradient Echo MRI.

Background: Quantitative parametric mapping is an increasingly important tool for noninvasive assessment of chronic liver disease. Conventional parametric mapping techniques require multiple breath-held acquisitions and provide limited anatomic coverage.

Purpose: To investigate a multi-inversion spin and gradient echo (MI-SAGE) technique for simultaneous estimation of T, T, and T* of the liver.

Impact of Emerging Deep Learning-Based MR Image Reconstruction Algorithms on Abdominal MRI Radiomic Features.

Objective: This study aims to evaluate, on one MRI vendor's platform, the impact of deep learning (DL)-based reconstruction techniques on MRI radiomic features compared to conventional image reconstruction techniques.

Methods: Under IRB approval and informed consent, we prospectively collected undersampled coronal T2-weighted MR images of the abdomen (1.5 T; Philips Healthcare) from 17 pediatric and adult subjects and reconstructed them using a conventional image reconstruction technique (compressed sensitivity encoding [C-SENSE]) and two DL-based reconstruction techniques (SmartSpeed [Philips Healthcare, US FDA cleared] and SmartSpeed with Super Resolution [SmartSpeed-SuperRes, not US FDA cleared to date]).

Quantitative MRI in children with Crohn's disease - where do we stand?

Crohn's disease (CD) is a chronic inflammatory condition that affects the gastrointestinal tract, particularly the ileum and colon. This disease is characterized by recurrent bouts of intestinal inflammation with subsequent bowel wall damage, including scarring (i.e.

Rapid abdominopelvic MR imaging in the emergency department: establishing a program and addressing the challenges.

Utilization of magnetic resonance imaging (MRI) in the pediatric emergency room or urgent care setting for abdominopelvic indications has been increasing. The creation and implementation of rapid urgent MRI programs can have various challenges. The purpose of this article is to describe a framework for the creation of a rapid urgent abdominopelvic MRI program in the pediatric emergency room setting.

Evaluation of 3D T1-weighted spoiled gradient echo MR image quality using artificial intelligence image reconstruction techniques in the pediatric brain.

Purpose: To assess image quality and diagnostic confidence of 3D T1-weighted spoiled gradient echo (SPGR) MRI using artificial intelligence (AI) reconstruction.

Materials And Methods: This prospective, IRB-approved study enrolled 50 pediatric patients (mean age = 11.8 ± 3.