The Natural History of Indeterminate Blunt Cerebrovascular Injury
Authors: Jeffrey D. Crawford, Kevin M. Allan, Karishma U. Patel, Kyle D. Hart, Martin A. Schreiber, Amir F. Azarbal, Timothy K. Liem, Erica L. Mitchell, Gregory L. Moneta, Gregory J. Landry
Journal: JAMA Surgery (2015)

lunt cerebrovascular injury (BCVI) is rare but potentially devastating, with a reported stroke rate of 3% to 59%, and disproportionately affects young adults. 1,2The location and severity of injury are dependent on the mechanism and can include intimal tear, intramural hematoma, pseudoaneurysm, dissection, occlusion, or transection as defined by the Denver criteria. 1,2Clinical diagnosis can be obfuscated by a lack of symptoms and confounding injuries in patients with trauma.The Denver criteria are based on angiographic findings; however, current screening protocols now use computed tomography, which has broadened screening protocols, resulting in increased identification of BCVIs.However, despite a robust classification scheme, there remains a large cohort of patients presenting with indeterminate BCVI (iBCVI) findings on initial imaging that do not strictly meet the Denver criteria.It is unknown what percentage of these lesions resolve, progress to a true BCVI, remain indeterminate when followed up serially, or result in cerebrovascular accident (CVA) or transient ischemic attack (TIA).Optimal treatment of these indeterminate lesions is also unknown.In this series, we review our institutional experience with iBCVI to determine the natural history of iBCVI, the risk of CVA or TIA, rate of resolution or reclassification, and demographic and/or clinical variables that affect outcomes. IMPORTANCEThe Denver criteria grade blunt cerebrovascular injuries (BCVIs) but fail to capture many patients with indeterminate findings on initial imaging.OBJECTIVE To evaluate outcomes and clinical significance of indeterminate BCVIs (iBCVIs). DESIGN, SETTING, AND PARTICIPANTSA retrospective review of all patients treated for BCVIs at our institution from January 1, 2007, through July 31, 2014, was completed.Patients were divided into 2 groups: those with true BCVIs as defined by the Denver criteria and those with iBCVIs, which was any initial imaging suggestive of a cerebrovascular arterial injury not classifiable by the Denver criteria. MAIN OUTCOMES AND MEASURESPrimary outcomes were rate of resolution of iBCVIs, freedom from cerebrovascular accident (CVA) or transient ischemic attack (TIA), and 30-day mortality. RESULTSWe identified 100 patients with 138 BCVIs: 79 with true BCVIs and 59 with iBCVIs.With serial imaging, 23 iBCVIs (39.0%) resolved and 21 (35.6%)remained indeterminate, whereas 15 (25.4%) progressed to true BCVI.The rate of CVA or TIA in the iBCVI group was 5.1% compared with 15.2% in the true BCVI group (P = .06).Of the 15 total CVAs or TIAs, 11 (73.3%)resulted from carotid injury and 4 (26.7%)from vertebral artery occlusion (P = .03).By Kaplan-Meier analysis, there was no difference in freedom from CVA or TIA for the 2 groups (P = .07).Median clinical follow-up was 91 days.Overall and 30-day mortality for the entire series were 17.4% and 15.2%, respectively.There was no difference in long-term or 30-day mortality between true BCVI and iBCVI groups.CONCLUSIONS AND RELEVANCE Detection of iBCVI has become a common clinical conundrum with improved and routine imaging.Indeterminate BCVI is not completely benign, with 25.4% demonstrating anatomical progression to true BCVI and 5.1% developing cerebrovascular symptoms.We therefore recommend serial imaging and antiplatelet therapy for iBCVI.