Development of a Simple MRI Scoring Tool in Severe Pediatric Traumatic Brain Injury: Secondary Analysis of the 2014-2017 "Approaches and Decisions in Acute Pediatric TBI Trial (ADAPT)" Multicenter Study.

OBJECTIVES

We aimed to describe the frequency, depth, and co-occurrence of different intracerebral injury types detected on the first clinical brain MRI in children with severe traumatic brain injury (TBI) and to derive a simple MRI scoring system associated with 12-month functional outcome.

DESIGN

Secondary analysis of the Approaches and Decision in Acute Pediatric TBI (ADAPT) multicenter 2014 to 2017 study.

SETTING

A total of 24 ADAPT sites in the United States, United Kingdom, and Australia.

PATIENTS: Children (< 18 yr) with severe TBI who received intracranial pressure monitoring and clinical brain MRI within 30 days of injury.

INTERVENTIONS: None.

MEASUREMENTS AND MAIN

RESULTS

MRI was evaluated for lesion type and location, and maximal depth of any lesion was determined for each subject (grade 1, lobar gray and white matter; grade 2, deep gray matter and corpus callosum; grade 3, brainstem). The primary outcome was Glasgow Outcome Scale Extended Pediatric version (GOSE-P) at 12 months, dichotomized to favorable (GOSE-P 1-3) vs. unfavorable (GOSE-P 4-8). In the cohort of 279 patients, we found that the three most frequent lesion types were contusion (78.5%), diffuse axonal injury (70.3%), and ischemia (38.0%). When evaluating maximal injury grade, grade 1 was present in 48 children (17.2%), grade 2 in 103 children (36.9%), and grade 3 in 113 children (40.5%). Injury grade and presence of ischemia were associated with increased odds of unfavorable outcome. Injury depth and ischemia on MRI (IDIOM) were incorporated into a novel six-category MRI Injury Scale, with scores ranging from 1 to 3+ (injury grades 1-3, + indicates presence of any ischemia). We found that score 3+, that is, brainstem injury with ischemia in any location, increased the risk of unfavorable outcome 22.3-fold (95% CI, 6.81-87.37; p < 0.0001) compared with score 1 (injury isolated to lobar gray and white matter, without ischemia).

CONCLUSIONS

Increased depth of injury and presence of ischemia on MRI are important risk factors for unfavorable outcome in children with severe TBI. We propose a simple MRI scoring system (IDIOM) that incorporates depth of injury and presence of ischemia that may be useful for neuroprognostication, but further validation is required.