Diffuse Axonal Injury Pattern Predicts Timing of In-Hospital Neurologic Recovery: A Retrospective Case Series

Diffuse axonal injury (DAI) is a devastating traumatic neurologic injury with variable prognosis. Although outcomes such as mortality have been described, the time course of neurologic progression is poorly understood. We investigated the association between DAI neuroanatomic injury pattern and neurologic recovery timing. A retrospective review of our institution's trauma registry identified patients diagnosed with DAI from 2017–2021. The neuroradiologist’s review of a head computed tomography scan was used to score DAI severity. In-hospital neurologic examinations were reviewed, and the Glasgow Coma Scale (GCS) was calculated for all patients throughout the hospital stay. Categorical variables were analyzed using the Fisher exact test, and continuous variables were analyzed using the Kruskal-Wallis test. Nineteen DAI patients (grade 1 = 8; grade 2 = 1; grade 3 = 10) were included (mean age 31 years, 79% male). Mean Rotterdam computed tomography score, Injury Severity Scale, and admission GCS were comparable across DAI grades. Mean time in days to follow commands was shorter for those with grade 1 DAI (9.3) compared with grade 2 (17 days) or grade 3 (19 days) DAI (P = 0.02). Throughout hospitalization, patients with grade 1 DAI had higher motor (P = 0.006), eye (P = 0.001), and total GCS (P = 0.011) scores compared with those with grade 2 or 3 DAI. At the time of discharge, total GCS and the frequency of command following was similar across DAI grades. Patients with grade 1 DAI demonstrated the fastest short-term neurologic recovery, although final discharge neurologic examination was comparable across DAI grades. DAI classification can provide useful short-term prognostic information regarding in-hospital neurologic improvement.