Setting up regional diagnostic reference levels for pediatric computed tomography in Latin America: preliminary results, challenges and the work ahead.

We established a framework for collecting radiation doses for head, chest and abdomen-pelvis computed tomography (CT) in children scanned at multiple imaging sites across Latin America with an aim towards establishing diagnostic reference levels (DRLs) and achievable doses (ADs) in pediatric CT in Latin America. Our study included 12 Latin American sites (in Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Honduras and Panama) contributing data on the four most common pediatric CT examinations (non-contrast head, non-contrast chest, post-contrast chest and post-contrast abdomen-pelvis). Sites contributed data on patients' age, sex and weight, scan factors (tube current and potential), volume CT dose index (CTDIvol) and dose length product (DLP).

Dynamic contrast enhanced MRI for characterization of blood-brain-barrier dysfunction after traumatic brain injury.

Background And Purpose: Dysfunction of the blood-brain-barrier (BBB) is a recognized pathological consequence of traumatic brain injury (TBI) which may play an important role in chronic TBI pathophysiology. We hypothesized that BBB disruption can be detected with dynamic contrast-enhanced (DCE) MRI not only in association with focal traumatic lesions but also in normal-appearing brain tissue of TBI patients, reflecting microscopic microvascular injury. We further hypothesized that BBB integrity would improve but not completely normalize months after TBI.

Arterial Spin Labeling Reveals Elevated Cerebral Blood Flow with Distinct Clusters of Hypo- and Hyperperfusion after Traumatic Brain Injury.

Imaging detection of brain perfusion alterations after traumatic brain injury (TBI) may provide prognostic insights. In this study, we used arterial spin labeling (ASL) to quantify cross-sectional and longitudinal changes in cerebral blood flow (CBF) after TBI and correlated changes with clinical outcome. We analyzed magnetic resonance imaging scans from adult participants with TBI requiring hospitalization in the acute (2 weeks post-injury,  = 33) and chronic (6 months post-injury,  = 16) phases, with 13 participants scanned longitudinally at both time points.

Inter-twin differences in fetal echocardiographic findings are associated with decreased dual twin survival in twin-twin transfusion syndrome.

Objective: To determine if inter-twin differences in fetal echocardiographic findings are associated with fetal survival in monochorionic pregnancies complicated by twin-to-twin transfusion syndrome (TTTS).

Methods: This study included women who underwent laser surgery for TTTS between 2012 and 2018 at a single institution. Echocardiographic cardiac parameters in the donor and recipient twins were compared using -scores and regression analyses (adjusted for confounding variables) to determine whether any measurable inter-twin differences were associated with neonatal survival at birth.

NFL blood levels are moderated by subconcussive impacts in a cohort of college football players.

Introduction: Repetitive subconcussive head impacts in contact/collision sports such as in US football are believed to contribute to long-term brain changes and chronic symptoms. However, the lack of tools to measure the effects of repeated subconcussion limits our understanding of potential contributions to neuropathological alterations including cellular damage.

Methods: We examined subconcussive head impacts using an accelerometer-embedded mouthguard on changes in blood levels of neurofilament light (NFL) chain in 18 Division I college football players.