Lindsay M. Griffin

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). Acquisition times were recorded, and signal intensity and apparent signal-to-noise ratio (aSNR) were calculated for the liver and spleen. Six blinded pediatric radiologists independently assessed image quality, artifacts, and lesion visualization on a 5-point Likert scale and identified their preferred sequence. Statistical comparisons were made using Kruskal-Wallis and ANOVA tests. Results Median acquisition times were significantly reduced with MB-DWI (43 s for MBsf1/MBsf2) compared to FB (84 s) and RTr (240 s). Image quality and artifact scores were highest for RTr and FB sequences (p < 0.0001). Mean image quality scores were 3.7 (RTr, FB), 3.4 (MBsf1), and 3.5 (MBsf2), while artifact scores followed a similar trend (higher score = fewer artifacts). Lesion visualization scores were comparable across sequences (p = 0.11), and reviewers expressed no preference in 47% of cases. Apparent diffusion coefficient (ADC) values were consistent across all sequences (p > 0.05). Conclusion MB-DWI significantly reduces acquisition time while maintaining acceptable image quality and lesion visualization, making it a valuable option for pediatric abdominal MRI.

The imaging evaluation of acute abdominal pain in children with suspected appendicitis has evolved to include rapid abdominopelvic MRI (rMRI) over recent years. Through a collaborative effort between the Magnetic Resonance Imaging (MRI) and Emergency and Trauma Imaging Committees of the Society for Pediatric Radiology (SPR), we conducted a survey on the utilization of rMRI to assess practice specifics and protocols. Subsequently, we present a proposed consensus rMRI protocol derived from the survey results, literature review, and discussion and consensus between committee members.

Magnetic resonance imaging (MRI) assessment of hepatic vasculature can be challenging in the setting of liver disease and liver lesions. The widely used hepatobiliary contrast agent gadoxetate is an extracellular contrast agent that provides excellent soft tissue characterization but has limitations as a vascular contrast agent. Ferumoxytol is an iron oxide nanoparticle with superparamagnetic properties that can be used as blood pool contrast agent to provide dedicated vascular assessment. We provide a detailed protocol for evaluation of pediatric liver vasculature using ferumoxytol, after imaging of the parenchyma with gadoxetate. We provide multiple examples and discuss practical considerations when incorporating ferumoxytol into practice.

Ferumoxytol-enhanced MRI using the pulse sequence four-dimensional multiphase steady-state imaging with contrast enhancement was feasible in a multicenter setting, shortened the examination time, a... Background The value of MRI in pediatric congenital heart disease (CHD) is well recognized; however, the requirement for expert oversight impedes its widespread use. Four-dimensional (4D) multiphas...