Clinical outcomes of diffuse axonal injury after traumatic brain injury according to magnetic resonance grading

Abstract

Diffuse axonal injury (DAI) occurs in approximately 40% to 50% of patients with severe traumatic brain injury (TBI) [1][2][3][4]. DAI is a shear injury caused by mechanical force and occurs as axial damage [5,6]. DAI contributes to increasing the duration of unconsciousness, mortality, and disability in patients with TBI [2,7]. Identifying DAI in patients with TBI helps predict the recovery of consciousness and clinical outcomes [2][3][4]8]. Furthermore, patients with DAI are often accompanied by damage in other body parts and mixed with several forms of intracranial hemorrhage in a complicated state. For these reasons, the outcome of patients with Objective: Diffuse axonal injury (DAI) is a severe form of traumatic brain injury (TBI) caused by shearing damage to the axons of long connecting fibers. In this study, we evaluated the clinical features according to DAI grading and identified prognostic factors. Methods: The study involved patients diagnosed with DAI using magnetic resonance imaging within 2 weeks of being hospitalized for TBI from January 2019 to December 2019. Patients who received surgical treatments, such as craniectomy or craniotomy for hematoma evacuation or an external ventricular drain, were excluded. To determine prognostic factors, we retrospectively reviewed the demographic, clinical, and radiological characteristics of 41 patients. Patients' outcomes were analyzed using the Glasgow Outcome Scale within 6 months of the traumatic injury. Results: Using a multivariate logistic regression model, unfavorable outcomes were significantly associated with lower Glasgow Coma Scale score (P=0.03), DAI grade III (P=0.03), DAI located at the stem (P=0.04), and the presence of 7 or more DAIs (P=0.03). However, DAI grade II was not a significant prognostic factor (P=0.76). Furthermore, the rates of hospital-acquired infection (P=0.04) and tracheostomy (P=0.03) significantly increased according to DAI grade. Conclusion:Our results provide valuable information on prognostic predictors in patients with TBI.