Peer Learning Program Metrics: A Pediatric Neuroradiology Example.

BACKGROUND AND PURPOSE: The American College of Radiology is now offering an accreditation pathway for programs that use peer learning. Here, we share feasibility and outcome data from a pilot peer learning program in a pediatric neuroradiology section that, in its design, follows the American College of Radiology peer learning accreditation pathway criteria. MATERIALS AND METHODS: We retrospectively reviewed metrics from a peer learning program with 5 participating full-time pediatric neuroradiologists during 1 year: 1) number of cases submitted, 2) percentage of radiologists meeting targets, 3) monthly attendance, 4) number of cases reviewed, 5) learning points, and 6) improvement actions. In addition, a faculty survey was conducted and is reported here. RESULTS: Three hundred twenty-four cases were submitted (mean, 7 cases/faculty/month). The faculty never met the monthly submission target. Peer learning meeting attendance was 100%. One hundred seventy-nine cases were reviewed during the peer learning meetings. There were 22 learning points throughout the year and 30 documented improvement actions. The faculty survey yielded the highest ratings (4.8 of 5) for ease of meeting the 100% attendance requirement and for the learning value of the peer learning sessions. The lowest rating (4.2 of 5) was given for the effectiveness of improvements as a result of peer learning discussions. CONCLUSIONS: Implementing a peer learning program that follows the American College of Radiology peer learning accreditation pathway criteria is feasible. Program metric documentation can be time-consuming. Participant feedback led to meaningful program improvement, such as improving trust, expanding case submission categories, and delegating tasks to administrative staff. Effort to make peer learning operations more efficient and more effective is underway.

High-Grade Gliomas in Children with Neurofibromatosis Type 1: Literature Review and Illustrative Cases.

High-grade gliomas in patients with neurofibromatosis type 1 are rare and may therefore not be considered in the differential of brain lesions. Here, we describe 5 children with neurofibromatosis type 1; four of them developed various types of high-grade gliomas. The fifth patient had imaging features concerning for a high-grade lesion, but tissue diagnosis showed a low-grade glioma. The cases and literature summary provided here are to raise awareness for the occurrence of high-grade gliomas in children with neurofibromatosis type 1 and the limited ability of imaging features alone to predict a high-grade malignancy.

Noncontrast Head CT in Children: National Variation in Radiation Dose Indices in the United States.

BACKGROUND AND PURPOSE: Radiologists should manage the radiation dose for pediatric patients to maintain reasonable diagnostic confidence. We assessed the variation in estimated radiation dose indices for pediatric noncontrast head CT in the United States. MATERIALS AND METHODS: Radiation dose indices for single-phase noncontrast head CT examinations in patients 18 years of age and younger were retrospectively reviewed between July 2011 and June 2016 using the American College of Radiology CT Dose Index Registry. We used the reported volume CT dose index stratified by patient demographics and imaging facility characteristics. RESULTS: The registry included 295,296 single-phase pediatric noncontrast head CT studies from 1571 facilities (56% in male patients and 53% in children older than 10 years of age). The median volume CT dose index was 33 mGy (interquartile range = 22-47 mGy). The volume CT dose index increased as age increased. The volume CT dose index was lower in children's hospitals (median, 26 mGy) versus academic hospitals (median, 32 mGy) and community hospitals (median, 40 mGy). There was a lower volume CT dose index in level I and II trauma centers (median, 27 and 32 mGy, respectively) versus nontrauma centers (median, 40 mGy) and facilities in metropolitan locations (median, 30 mGy) versus those in suburban and rural locations (median, 41 mGy). CONCLUSIONS: Considerable variation in the radiation dose index for pediatric head CT exists. Median dose indices and practice variations at pediatric facilities were both lower compared with other practice settings. Decreasing dose variability through proper management of CT parameters in pediatric populations using benchmarks generated by data from registries can potentially decrease population exposure to ionizing radiation.

FLAIR and magnetization transfer imaging of patients with post-treatment Lyme disease syndrome.

OBJECTIVE: To determine patterns of abnormalities on cerebral MRI that may characterize subgroups of patients with post-treatment Lyme disease syndrome (PTLDS) and to help identify pathomechanisms of disease. METHODS: The authors analyzed the distribution of cerebral lesions in a cohort of 27 patients with PTLDS. A subgroup of eight patients with PTLDS was further studied using whole-brain magnetization transfer ratio measures to identify abnormalities not seen on T2-weighted images. RESULTS: Four patients had focal neurologic deficits, relapsing-remitting disease, and lesions in a distribution typical of MS. Twenty-three patients presented with nonfocal symptoms such as fatigue, subjective memory deficits, and mood disturbance. Twelve of these patients had normal MRI, including the more sensitive fluid-attenuated inversion recovery sequence, 10 had primarily punctate and subcortical lesions, and one patient had multiple periventricular lesions. CONCLUSIONS: In a portion of patients with post-treatment Lyme disease syndrome, white-matter hyperintensities tend to occur in subcortical arteriolar watershed areas and are not specific. Magnetization transfer ratio analysis did not provide evidence for structural abnormalities of the brain parenchyma in patients with nonfocal disease.

Utility of magnetization transfer T1 imaging in children with seizures.

Failure to detect FCD and similar lesions encountered in patients with tuberous sclerosis can have significant clinical consequences, such as preventing surgical intervention for medically refractory epilepsy and misguiding prognostic information regarding cognitive development. Here, we show the beneficial effects on detection of FCD and cortical tubers when using a magnetization transfer T1 sequence for children with seizures who underwent MR imaging at our institution.

Quantitative analysis of magnetic resonance images and neurological outcome in encephalopathic neonates treated with whole-body hypothermia.

OBJECTIVE: To evaluate whether quantitative measures from magnetic resonance imaging (MRI) performed in hypothermia-treated encephalopathic newborns can differentiate patients with unfavorable neurological outcome. STUDY DESIGN: Retrospective analysis of clinical data and MRI studies was performed in 47 full-term infants treated with whole-body hypothermia for neonatal encephalopathy. Apparent diffusion coefficients (ADCs) and T1 and T2 intensity ratios were measured in the basal ganglia and thalamus on axial MRI images. Unfavorable outcome was defined as (1) death or severe neurological deficits at discharge and (2) death or cerebral palsy/severe motor deficit at follow-up through age 9 months. Differences between groups with favorable versus unfavorable neurological outcome at each time point were compared. Optimal cutoff values for significant MR variables were determined with receiver operating curve analyses. Sensitivity and specificity of these cutoff values for predicting unfavorable outcome were calculated and results were compared with qualitative MRI interpretation. RESULT: Infants presented with a median pH of 6.86, base deficit of 20 and Apgar scores of 1, 3 and 4 at 1, 5 and 10 min, respectively. Severe encephalopathy was present in 38%. Unfavorable outcome was present in 9 patients at discharge and in 13 of 26 patients with available follow-up data through 9 months. ADC values and T1 ratios were not significantly different between groups at either time point. T2 ratios in both the basal ganglia and thalamus were significantly higher in patients with unfavorable outcome, both at discharge and in follow-up. T2 intensity ratio in the basal ganglia and thalamus remained significantly associated with death or severe neurological deficit at discharge, after controlling for covariates in logistic regression analysis. Sensitivity and specificity of T2 intensity ratio for predicting unfavorable outcome at discharge were comparable to qualitative grading of injury in the basal ganglia and thalamus by a neuroradiologist. CONCLUSION: Increased T2 signal intensity in the basal ganglia or thalamus in patients with hypothermia-treated neonatal encephalopathy is associated with unfavorable neurological outcome at discharge and later with motor deficit/cerebral palsy. Quantitative methods to assess MRI evidence of brain injury are important for providing objective measures to predict outcome in this high-risk population.

MRI as a marker for disease heterogeneity in multiple sclerosis.

BACKGROUND: Whereas recent data from imaging studies challenge the prevailing notion that multiple sclerosis (MS) is purely an inflammatory disease, pathologic studies suggest differences in the disease processes between individual patients with MS. The ability to dissect the pathophysiologic disease heterogeneity, if it indeed exists, by methodologies that can be applied in vivo is important both for the development of new therapeutics and for the ability to identify the optimal therapy for an individual patient. OBJECTIVE: To design a stratification algorithm for patients with MS based on accepted MRI measurements reflective of inflammation and axonal damage/tissue loss and to assess if such MS subgroups retain their intergroup differences long term. METHODS: Mathematical modeling was used to select three discriminatory MRI measures for clinical outcome based on the cross-sectional analysis of 71 patients with untreated MS and tested general applicability of the stratification scheme on the independent longitudinal cohort of 71 MS patients. RESULTS: By consecutive employment of MRI measures reflective of inflammation and tissue loss, the authors were able to separate MS patients into four clinically meaningful subgroups. The analysis of the longitudinal confirmatory cohort demonstrated persistence of the intergroup differences in selected MRI measures for 8 years. CONCLUSIONS: The inflammatory activity and destructiveness of the multiple sclerosis process are to some degree independent of each other, and the successive evaluation of both of these variables can strengthen prediction of clinical outcome in individual patients.