Assessing Pediatric Mild Traumatic Brain Injury and Its Recovery Using Resting-State Magnetoencephalography Source Magnitude Imaging and Machine Learning.

The objectives of this machine-learning (ML) resting-state magnetoencephalography (rs-MEG) study involving children with mild traumatic brain injury (mTBI) and orthopedic injury (OI) controls were to define a neural injury signature of mTBI and to delineate the pattern(s) of neural injury that determine behavioral recovery. Children ages 8-15 years with mTBI (n = 59) and OI (n = 39) from consecutive admissions to an emergency department were studied prospectively for parent-rated post-concussion symptoms (PCS) at: 1) baseline (average of 3 weeks post-injury) to measure pre-injury symptoms and also concurrent symptoms; and 2) at 3-months post-injury. rs-MEG was conducted at the baseline assessment. The ML algorithm predicted cases of mTBI versus OI with sensitivity of 95.5 ± 1.6% and specificity of 90.2 ± 2.7% at 3-weeks post-injury for the combined delta-gamma frequencies. The sensitivity and specificity were significantly better (p < 0.0001) for the combined delta-gamma frequencies compared with the delta-only and gamma-only frequencies. There were also spatial differences in rs-MEG activity between mTBI and OI groups in both delta and gamma bands in frontal and temporal lobe, as well as more widespread differences in the brain. The ML algorithm accounted for 84.5% of the variance in predicting recovery measured by PCS changes between 3 weeks and 3 months post-injury in the mTBI group, and this was significantly lower (p < 10-4) in the OI group (65.6%). Frontal lobe pole (higher) gamma activity was significantly (p < 0.001) associated with (worse) PCS recovery exclusively in the mTBI group. These findings demonstrate a neural injury signature of pediatric mTBI and patterns of mTBI-induced neural injury related to behavioral recovery.

Three-Month Psychiatric Outcome of Pediatric Mild Traumatic Brain Injury: A Controlled Study.

The objective was to clarify occurrence, phenomenology, and risk factors for novel psychiatric disorder (NPD) in the first 3 months after mild traumatic brain injury (mTBI) and orthopedic injury (OI). Children aged 8-15 years with mTBI (n = 220) and with OI but no TBI (n = 110) from consecutive admissions to an emergency department were followed prospectively at baseline and 3 months post-injury with semi-structured psychiatric interviews to document the number of NPDs that developed in each participant. Pre-injury child variables (adaptive, cognitive, and academic function, and psychiatric disorder), pre-injury family variables (socioeconomic status, family psychiatric history, and family function), and injury severity were assessed and analyzed as potential confounders and predictors of NPD. NPD occurred at a significantly higher frequency in children with mTBI versus OI in analyses unadjusted (mean ratio [MR] 3.647, 95% confidence interval [CI95] (1.264, 15.405), p = 0.014) and adjusted (MR = 3.724, CI95 (1.264, 15.945), p = 0.015) for potential confounders. In multi-predictor analyses, the factors besides mTBI that were significantly associated with higher NPD frequency after adjustment for each other were pre-injury lifetime psychiatric disorder [MR = 2.284, CI95 (1.026, 5.305), p = 0.043]; high versus low family psychiatric history [MR = 2.748, CI95 (1.201, 6.839), p = 0.016], and worse socio-economic status [MR = 0.618 per additional unit, CI95 (0.383, 0.973), p = 0.037]. These findings demonstrate that mild injury to the brain compared with an OI had a significantly greater deleterious effect on psychiatric outcome in the first 3 months post-injury. This effect was present even after accounting for specific child and family variables, which were themselves independently related to the adverse psychiatric outcome.

Resting-State Magnetoencephalography Source Imaging Pilot Study in Children with Mild Traumatic Brain Injury.

Mild traumatic brain injury (mTBI) accounts for the vast majority of all pediatric TBI. An important minority of children who have suffered an mTBI have enduring cognitive and emotional symptoms. However, the mechanisms of chronic symptoms in children with pediatric mTBI are not fully understood. This is in part due to the limited sensitivity of conventional neuroimaging technologies. The present study examined resting-state magnetoencephalography (rs-MEG) source images in 12 children who had mTBI and 12 age-matched control children. The rs-MEG exams were performed in children with mTBI 6 months after injury when they reported no clinically significant post-injury psychiatric changes and few if any somatic sensorimotor symptoms but did report cognitive symptoms. MEG source magnitude images were obtained for different frequency bands in alpha (8-12 Hz), beta (15-30 Hz), gamma (30-90 Hz), and low-frequency (1-7 Hz) bands. In contrast to the control participants, rs-MEG source imaging in the children with mTBI showed: 1) hyperactivity from the bilateral insular cortices in alpha, beta, and low-frequency bands, from the left amygdala in alpha band, and from the left precuneus in beta band; 2) hypoactivity from the bilateral dorsolateral prefrontal cortices (dlPFC) in alpha and beta bands, from the ventromedial prefrontal cortex (vmPFC) in beta band, from the ventrolateral prefrontal cortex (vlPFC) in gamma band, from the anterior cingulate cortex (ACC) in alpha band, and from the right precuneus in alpha band. The present study showed that MEG source imaging technique revealed abnormalities in the resting-state electromagnetic signals from the children with mTBI.