Use of MRI in patients with severe diffuse traumatic brain injury: A matched National Trauma Data Bank analysis

Abstract

OBJECTIVE Magnetic resonance imaging (MRI) is increasingly used to evaluate patients with diffuse traumatic brain injury (dTBI). However, the utility of early MRI is understudied. We hypothesize that early MRI patients will have increased length of stay but no changes in intracranial pressure (ICP) management or disposition. METHODS The 2019 National Trauma Data Bank was queried for patients with dTBI and Glasgow Coma Scale score ≤8. Extra-axial and focal intra-axial hemorrhages were excluded. Clinical characteristics were controlled for. Patients with and without MRI were compared for ICP management, outcome, mortality, and disposition. A propensity score matching algorithm was used to create a 1:1 match cohort. RESULTS In 2568 patients, MRI was less common in severe dTBI patients with clear reasons for poor examination, including bilaterally unreactive pupils or midline shift. After matching, 501 patients who underwent MRI within 1 week were compared with 501 patients without MRI. Magnetic resonance imaging patients had longer intensive care unit stays (11.6 ± 9.6 vs. 13.4 ± 9.5, p < 0.01; 95% confidence interval [95% CI], −3.03 to −0.66). There was no difference between groups in ICP monitor (23.6% vs. 27.3%; p = 0.17; 95% CI, −0.09 to 0.02) or ventriculostomy placement (13.6% vs. 13.2%, p = 0.85; 95% CI, −0.04 to 0.05) or in withdrawal of care (15.0% vs. 18.6%, p = 0.12; 95% CI, −0.08 to 0.01). MRI patients were more likely to be discharged to inpatient rehabilitation (42.9% vs. 33.5%; p < 0.01; 95% CI, 0.03–0.15) but not to home (9.4% vs. 9.0%; p = 0.83; 95% CI, −0.03 to 0.04). CONCLUSION The decision to pursue early brain MRI may be driven by lack of obvious reasons for a patient's poor neurologic status. MRI patients had longer intensive care unit stays but no difference in rates of placement of ICP monitors or ventriculostomies or withdrawal of care. Further study is required to define the role of early MRI in dTBI patients. LEVEL OF EVIDENCE Prognostic and Epidemiological; Level IV