Internal medicine

Radiology

Pediatrics

Injury prevention

Glasgow Outcome Scale

Poison control

Psychiatry

Magnetic resonance imaging

Interquartile range

Surgery

Glasgow Coma Scale

Emergency medicine

Abbreviated Injury Scale

Diffuse axonal injury

Traumatic brain injury

Cohort

Medicine

Injury Severity Score

Journal of Trauma and Acute Care Surgery

BACKGROUND Determine the prognostic impact of magnetic resonance imaging (MRI)-defined diffuse axonal injury (DAI) after traumatic brain injury (TBI) on functional outcomes, quality of life, and 3-year mortality. METHODS This retrospective single center cohort included adult trauma patients (age &gt; 17 years) admitted from 2006 to 2012 with TBI. Inclusion criteria were positive head computed tomography with brain MRI within 2 weeks of admission. Exclusion criteria included penetrating TBI or prior neurologic condition. Separate ordinal logistic models assessed DAI's prognostic value for the following scores: (1) hospital-discharge Functional Independence Measure, (2) long-term Glasgow Outcome Scale-Extended, and (3) long-term Quality of Life after Brain Injury-Overall Scale. Cox proportional hazards modeling assessed DAI's prognostic value for 3-year survival. Covariates included age, sex, race, insurance status, Injury Severity Score, admission Glasgow Coma Scale Score, Marshall Head computed tomography Class, clinical DAI on MRI (Y/N), research-level anatomic DAI Grades I-III (I, cortical; II, corpus callosum; III, brainstem), ventilator days, time to follow commands, and time to long-term follow-up (for logistic models). RESULTS Eligibility criteria was met by 311 patients, who had a median age of 40 years (interquartile range [IQR], 23–57 years), Injury Severity Score of 29 (IQR, 22–38), intensive care unit stay of 6 days (IQR, 2–11 days), and follow-up of 5 years (IQR, 3–6 years). Clinical DAI was present on 47% of MRIs. Among 300 readable MRIs, 56% of MRIs had anatomic DAI (25% Grade I, 18% Grade II, 13% Grade III). On regression, only clinical (not anatomic) DAI was predictive of a lower Functional Independence Measure score (odds ratio, 2.5; 95% confidence interval, 1.28–4.76], p = 0.007). Neither clinical nor anatomic DAI were related to survival, Glasgow Outcome Scale-Extended, or Quality of Life after Brain Injury-Overall Scale scores. CONCLUSION In this longitudinal cohort, clinical evidence of DAI on MRI may only be useful for predicting short-term in-hospital functional outcome. Given no association of DAI and long-term TBI outcomes, providers should be cautious in attributing DAI to future neurologic function, quality of life, and/or survival. LEVEL OF EVIDENCE Epidemiological, level III; Therapeutic, level IV.

Prognosis of diffuse axonal injury with traumatic brain injury