Use of computed tomography in the emergency room to evaluate blunt cerebrovascular injury

Abstract

BCVI remains a potentially devastating consequence of blunt-force trauma. However, over the past decades significant advances have been made in understanding the pathophysiology, risk factors, and natural history of BCVI. Given the initial asymptomatic period, there is time to diagnose and treat these lesions before the onset of neurologic insult. This early recognition and intervention greatly improves morbidity and mortality directly associated with BCVI. Screening criteria have been identified and reviewed. All patients at risk of BCVI, based on mechanism of injury and risk factors, should be rapidly evaluated for possible injury. It is the authors' current belief that even the newest generation of CT scanners has not been proved to reliably diagnose BCVI. Until further work is done to advance the technology of CTA and prove its equivalence to DSA, there exists too much potential neurologic morbidity and mortality for one to rely on CTA alone (Table 2). Given the variable, and often low, reported sensitivities of CTA, the cost analysis done by Kaye and colleagues [23] would also recommend initial DSA as being cost-effective in avoiding the long-term devastating sequelae of stroke. At the time of writing the authors recommend that CTA be included in an algorithm to evaluate BCVI, but the current data are too disparate with widely variable reported sensitivities, and the risk of missed injury and stroke too severe, to rely on CTA as the definitive diagnostic or screening test for BCVI. Rather, abnormal CTA findings should be added to the traditional screening criteria to identify patients at risk of BCVI; these patients should be evaluated with DSA for definitive screening. Adding abnormal CTA findings to the traditionally described BCVI screening criteria widens the criteria substantially, allowing identification of almost all of the elusive 20% of patients traditionally not identified with basic screening criteria. In addition, given the high specificity of CTA and the decreased morbidity of BCVI with rapid institution of treatment, the authors recommend beginning a low-dose heparin drip (if there are no contraindications to anticoagulation) based on CTA findings while awaiting the confirmatory DSA. Despite advances in CTA technology in recent years, DSA currently remains the gold standard for the diagnosis of BCVI. All patients with standard risk factors for BCVI, or abnormal findings on CTA, should undergo DSA as the screening test of choice for BCVI.