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Published on: June 18, 2021
Evaluating the Utility of Repeat Computed Tomography Scans in Patients with Isolated Mild Traumatic Subarachnoid
Noah L A Nawabi1, John L Kilgallon2, Jack J McNulty3
1Computational Neuroscience Outcomes Center, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA; Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA; College of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA.
Background:
Traumatic subarachnoid hemorrhage (tSAH) is a common consequence of head trauma. Treatment of patients with tSAH commonly involves serial computed tomography (CT) scans to assess for expansile hemorrhage. However, growing evidence suggests that these patients rarely deteriorate or require neurosurgical intervention. We assessed the utility of repeat CT scans in adult patients with isolated tSAH and an intact initial neurological examination.
Methods:
Patients presenting to Mass General Brigham hospitals with tSAH between 2000 and 2021 were eligible for inclusion in this retrospective cohort study. Patients were excluded if subarachnoid hemorrhage was nontraumatic, they experienced another form of intracerebral hemorrhage, or they had a documented Glasgow Coma Scale score of ≤12 and/or poor presenting neurological examination. Univariate and multivariate regression models were used for statistical analysis.
Results:
Overall, 405 patients were included (191 male). The most common mechanism of trauma was fall from standing (58%). The mean number of total CT scans for all patients was 2.3, with 329 patients (80%) receiving ≥2 scans. In 309 patients, no significant neurological symptoms were present. No patients developed acute neurological deterioration or required neurosurgical intervention related to their bleed, although 5 patients had mild hemorrhagic expansion on follow-up imaging.
Conclusions:
In this study, repeat imaging rarely demonstrated meaningful hemorrhagic expansion in this cohort of neurologically intact patients with isolated tSAH. In these patients with mild traumatic brain injury, excessive CT scans are perhaps unlikely to affect patient management and may present unnecessary burden to patients and hospital systems.

