Management of blunt extracranial traumatic cerebrovascular injury: a multidisciplinary survey of current practice

Diagnosis and management of blunt cerebrovascular injuries: What you need to know

ABSTRACT

Blunt cerebrovascular injuries are not as rare as they were once thought to be-but they still have the same potential for disastrous outcomes. They may occur following any trauma, but more common with higher energy transfer mechanisms. If stroke occurs, prompt recognition and treatment offers the best chance for optimal outcome. Early diagnosis and provision of antithrombotic therapy may prevent strokes, so screening of asymptomatic patients is recommended. Herein we will present what you need to know to diagnose and manage blunt cerebrovascular injury.

Antiplatelets versus anticoagulants in the treatment of blunt cerebrovascular injury (BCVI) - A systematic review and meta-analysis

INTRODUCTION

Blunt cerebrovascular injury (BCVI) occurs in 1-3% of blunt traumas and is associated with stroke, disability, and mortality if unrecognized and untreated. Early detection and treatment are imperative to reduce the risk of stroke, however, there is significant variation amongst centers and trauma care providers in the specific medical management strategy used. This study compares antiplatelets vs. anticoagulants to determine BCVI-related stroke risk and bleeding complications to better understand the efficacy and safety of various treatment strategies.

METHODS

A systematic review of MEDLINE, Embase, and Cochrane CENTRAL databases was conducted with the assistance of a medical librarian. The search was supplemented with manual review of the literature. Included studies reported treatment-stratified risk of stroke following BCVI. All studies were screened independently by two reviewers, and data was extracted in duplicate. Meta-analysis was conducted using pooled estimates of odds ratios (OR) with a random-effects model using Mantel-Haenszel methods.

RESULTS

A total of 3315 studies screened yielded 39 studies for inclusion, evaluating 6552 patients (range 8 - 920 per study) with a total of 7643 BCVI. Stroke rates ranged from 0% to 32.8%. Amongst studies included in the meta-analysis, there were a total of 405 strokes, with 144 (35.5%) occurring on therapy, for a total stroke rate of 4.5 %. Meta-analysis showed that stroke rate after BCVI was lower for patients treated with antiplatelets vs. anticoagulants (OR 0.57; 95% CI 0.33-0.96, p = 0.04); when evaluating only the 9 studies specifically comparing ASA to heparin, the stroke rate was similar between groups (OR 0.43; 95% CI 0.15-1.20, p = 0.11). Eleven studies evaluated bleeding complications and demonstrated lower risk of bleeding with antiplatelets vs. anticoagulants (OR 0.29; 95% CI 0.13-0.63, p = 0.002); 5 studies evaluating risk of bleeding complications with ASA vs. heparin showed lower rates of bleeding complications with ASA (OR 0.16; 95% CI 0.04-0.58, p = 0.005).

CONCLUSIONS

Treatment of patients with BCVI with antiplatelets is associated with lower risks of stroke and bleeding complications compared to treatment with anticoagulants. Use of ASA vs. heparin specifically was not associated with differences in stroke risk, however, patients treated with ASA had fewer bleeding complications. Based on this evidence, antiplatelets should be the preferred treatment strategy for patients with BCVI.

Efficacy of Antithrombotic Therapy and Risk of Hemorrhagic Complication in Blunt Cerebrovascular Injury Patients with Concomitant Injury: A Systematic Review

BACKGROUND

The risk-benefit balance of antithrombotic therapy administration for blunt cerebrovascular injuries (BCVI) patients with concomitant injuries at high risk for bleeding is an ongoing therapeutic conundrum for trauma clinicians. We performed a systematic review to assess the reported efficacy and safety of treatment in this population with respect to prevention of ischemic stroke and risk of hemorrhagic complications.

STUDY DESIGN

A systematic electronic literature search of MEDLINE, EMBASE, Cochrane Library, and Web of Science databases was performed from January 1, 1996 to December 31, 2021. Studies were included if they reported treatment-stratified clinical outcomes after antithrombotic therapy in BCVI patients with concomitant injuries at high risk of bleeding into a critical site. Data were extracted from selected studies by two independent reviewers, including the main outcomes of interest were BCVI-related ischemic stroke rates and rates of hemorrhagic complications.

RESULTS

Of the 5,999 studies reviewed, 10 reported on the effects of treating BCVI patients with concurrent traumatic injuries and were included for review. In the pooled data, among patients with BCVI and concomitant injury who received any form of antithrombotic therapy, the BCVI-related stroke rate was 7.6%. The subgroup of patients who did not receive therapy had an overall BCVI-related stroke rate of 34%. The total rate of hemorrhagic complications in the treated population was 3.4%.

CONCLUSIONS

In BCVI patients with concomitant injuries at high risk for bleeding, antithrombotic use reduces the risk of ischemic strokes with a low reported risk of serious hemorrhagic complications.

Grade 1 Internal Carotid Artery Blunt Cerebrovascular Injury Persistence Risks Stroke With Current Management: An EAST Multicenter Study

BACKGROUND

Higher blunt cerebrovascular injury (BCVI) grade and lack of medical therapy are associated with stroke. Knowledge of stroke risk factors specific to individual grades may help tailor BCVI therapy to specific injury characteristics.

METHODS

A post-hoc analysis of a 16 center, prospective, observational trial (2018-2020) was performed including grade 1 internal carotid artery (ICA) BCVI. Repeat imaging was considered the second imaging occurrence only.

RESULTS

From 145 grade 1 ICA BCVI included, 8 (5.5%) suffered a stroke. Grade 1 ICA BCVI with stroke were more commonly treated with mixed anticoagulation and antiplatelet therapy (75.0% vs 9.6%, P <.001) and less commonly antiplatelet therapy (25.0% vs 82.5%, P = .001) compared to injuries without stroke. Of the 8 grade 1 ICA BCVI with stroke, 4 (50.0%) had stroke after medical therapy was started. In comparing injuries with resolution at repeat imaging to those without, stroke occurred in 7 (15.9%) injuries without resolution and 0 (0%) injuries with resolution (P = .005). At repeat imaging in grade 1 ICA BCVI with stroke, grade of injury was grade 1 in 2 injuries, grade 2 in 3 injuries, grade 3 in 1 injury, and grade 5 in one injury.

DISCUSSION

While the stroke rate for grade 1 ICA BCVI is low overall, injury persistence appears to heighten stroke risk. Some strokes occurred despite initiation of medical therapy. Repeat imaging is needed in grade 1 ICA BCVI to evaluate for injury progression or resolution.

Neurointerventional management of cerebrovascular trauma

Traumatic cerebrovascular injuries following blunt or penetrating trauma are common and carry a high risk of permanent disability or death. Proper screening, diagnosis, and treatment of these lesions is essential to improve patient outcomes. Advances in imaging continue to improve the accuracy of non-invasive diagnosis of these injuries while new clinical data provide better evidence for optimal management, whether medical or invasive. Here, we review screening, diagnosis, and treatment of traumatic cerebrovascular injuries.

Existence of knowledge silos in the adult blunt cerebrovascular injury literature

Background

Blunt cerebrovascular injuries (BCVI) remain a significant source of disability and mortality among trauma patients. The purpose of the present study was to determine whether knowledge silos exist in the overall BCVI literature.

Methods

An object-oriented programmatic script written in Python programming language was used to extract and categorize articles and references on the topic of BCVI. Additionally, each BCVI article was searched for by digital object identifier in the other BCVI references to build a network analysis and visualize topic reference patterns. Analyses were performed using Stata V.14.2 (StataCorp).

Results

A total of 306 articles with 10 282 references were included for analysis. Of these, 24% (74) were published in neurosurgery journals, 45% (137) were published in trauma journals, and 31% (95) were published in a journal of another specialty. Similar proportions were found when categorized by author departmental affiliation. Trauma surgery authors disproportionately referenced articles in the trauma literature, compared with neurosurgeons (73.5% vs. 48.0%, p<0.0001), and other authors. The biggest factor influencing reference proportions was the specialty of the publishing journal. Finally, a network analysis revealed that there are more trauma BCVI articles, and there are more frequently cited trauma BCVI articles by all specialties.

Conclusions

This study revealed the existence of a one-way knowledge silo in the BCVI literature. However, a robust preference by both trauma and neurosurgery to cite trauma references when publishing in trauma journals may indicate a possible conscious curating of citations by authors to increase the likelihood of publication. These observations highlight the need for an active role by journal editors, peer reviewers, and authors to actively foster diversity of citations and cross-specialty collaboration to improve dissemination of information between these specialties.

Level of evidence

Level IV. Observational study.

Neurointerventional management of cerebrovascular trauma

Traumatic cerebrovascular injuries following blunt or penetrating trauma are common and carry a high risk of permanent disability or death. Proper screening, diagnosis, and treatment of these lesions is essential to improve patient outcomes. Advances in imaging continue to improve the accuracy of non-invasive diagnosis of these injuries while new clinical data provide better evidence for optimal management, whether medical or invasive. Here, we review screening, diagnosis, and treatment of traumatic cerebrovascular injuries.

Aspirin versus anticoagulation for stroke prophylaxis in blunt cerebrovascular injury: a propensity-matched retrospective cohort study

OBJECTIVE

The goal of this study was to compare the odds of stroke 24 hours or more after hospital arrival among patients with blunt cerebrovascular injury (BCVI) who were treated with therapeutic anticoagulation versus aspirin.

METHODS

The authors conducted a retrospective cohort study at a regional level I trauma center including all patients with BCVI who were treated over a span of 10 years. Individuals with stroke on arrival or within the first 24 hours were excluded, as were those receiving alternative antithrombotic drugs or procedural treatment. Exact logistic regression was used to examine the association between treatment and stroke, adjusting for injury grade. To account for the possibility of residual confounding, propensity scores for the likelihood of receiving anticoagulation were determined and used to match patients from each treatment group; the difference in the probability of stroke between the two groups was then calculated.

RESULTS

A total of 677 patients with BCVI receiving aspirin or anticoagulation were identified. A total of 3.8% (n = 23) of 600 patients treated with aspirin sustained a stroke, compared to 11.7% (n = 9) of 77 receiving anticoagulation. After adjusting for injury grade with exact regression, anticoagulation was associated with higher likelihood of stroke (OR 3.01, 95% CI 1.00-8.21). In the propensity-matched analysis, patients who received anticoagulation had a 15.0% (95% CI 3.7%-26.3%) higher probability of sustaining a stroke compared to those receiving aspirin.

CONCLUSIONS

Therapeutic anticoagulation may be inferior to aspirin for stroke prevention in BCVI. Prospective research is warranted to definitively compare these treatment strategies.

Antithrombotic choice in blunt cerebrovascular injuries: Experience at a tertiary trauma center, systematic review, and meta-analysis

BACKGROUND

Blunt cerebrovascular injuries (BCVIs) may occur following trauma and lead to ischemic stroke if untreated. Antithrombotic therapy decreases this risk; however, the optimal agent has yet to be determined in this population. The aim of this study was to compare the risk-benefit profile of antiplatelet (AP) versus anticoagulant (AC) therapy in rates of ischemic stroke and hemorrhagic complications in BCVI patients.

METHODS

We performed a retrospective review of BCVI patients at our tertiary care Trauma hospital from 2010 to 2015, and a systematic review and meta-analysis of the literature. The OVID Medline, Embase, Web of Science, and Cochrane Library databases were searched from inception to September 16, 2019. References of included publications were searched manually for other relevant articles. The search was limited to articles in humans, in patients 18 years or older, and in English. Studies that reported treatment-stratified clinical outcomes following AP or AC treatment in BCVI patients were included. Exclusion criteria included case reports, case series with n < 5, review articles, conference abstracts, animal studies, and non-peer-reviewed publications. Data were extracted from each study independently by two reviewers, including study design, country of origin, sex and age of patients, Injury Severity Score, Biffl grade, type of treatment, ischemic stroke rate, and hemorrhage rate. Pooled estimates using odds ratio (OR) were combined using a random-effects model using a Mantel-Hanzel weighting. The main outcome of interest was rate of ischemic stroke due to BCVI, and the secondary outcome was hemorrhage rate based on AC or AP treatment.

RESULTS

In total, there were 2044 BCVI patients, as reported in the 22 studies in combination with our institutional data. The stroke rate was not significantly different between the two treatment groups (OR, 1.27; 95% confidence interval, 0.40-3.99); however, the hemorrhage rate was decreased in AP versus AC treated groups (OR, 0.38; 95% confidence interval, 0.15-1.00).

CONCLUSION

Based on this meta-analysis, both AC and AP seem similarly effective in preventing ischemic stroke, but AP is better tolerated in the trauma population. This suggests that AP therapy may be preferred, but this should be further assessed with prospective randomized trials.

LEVEL OF EVIDENCE

Review article, level II.

New ischemic lesions on brain magnetic resonance imaging in patients with blunt traumatic cerebrovascular injury

BACKGROUND

Patients with blunt cerebrovascular injuries are at risk of thromboembolic stroke. Although primary prevention with antithrombotic therapy is widely used in this setting, its effectiveness is not well defined and requires further investigation. The aim of this study was to evaluate the utility of magnetic resonance imaging (MRI)-detected ischemic brain lesions as a possible future outcome for randomized clinical trials in this patient population.

METHODS

This prospective observational study included 20 adult blunt trauma patients admitted to a level I trauma center with a screening neck CTA showing extracranial carotid or vertebral artery injury. All subjects lacked initial evidence of an ischemic stroke and were managed with antithrombotic therapy and observation and then underwent brain MRI within 30 days of the injury to assess for ischemic lesions. The MRI scans included diffusion, susceptibility, and Fluid-attenuated Inversion Recovery (FLAIR) sequences, and were reviewed by two neuroradiologists blinded to the computed tomography angiography (CTA) findings.

RESULTS

Eleven CTAs were done in the emergency department upon admission. There were 12 carotid artery dissections and 11 unilateral or bilateral vertebral artery injuries. Median interval between injury and MRI scan was 4 days (range, 0.1-14; interquartile range, 3-7 days). Diffusion-weighted imaging evidence of new ischemic lesions was present in 10 (43%) of 23 of the injured artery territories. In those injuries with ischemic lesions, the median number was 8 (range, 2-25; interquartile range, 5-8). None of the lesions were symptomatic. Blunt cerebrovascular injury was associated with a higher mean ischemic lesion count (mean count of 3.17 vs. 0.14, p < 0.0001), with the association remaining after adjusting for injury severity score (p < 0.0001).

CONCLUSION

In asymptomatic blunt trauma patients with CTA evidence of extracranial cerebrovascular injury and treated with antithrombotic therapy, nearly half of arterial injuries are associated with ischemic lesions on MRI.

LEVEL OF EVIDENCE

Therapeutic/care management, level IV.

Pharmacologic Therapy is Not Associated with Stroke Prevention in Patients with Isolated Blunt Vertebral Artery Injury

BACKGROUND

Vertebral artery injury (VAI) is often grouped with carotid artery injury into a broader classification of blunt cerebrovascular injury, despite fundamental differences in mechanism of injury and outcome. This study seeks to evaluate the efficacy of medical therapy in preventing strokes for isolated VAI.

METHODS

Patients with isolated blunt VAI (2011-2018) were identified from the trauma registry of a level I trauma center. A retrospective chart review was conducted excluding patients with concomitant carotid artery injury. Factors examined included demographics, injury characteristics, anatomic classification, and management strategy. Patients were stratified by whether they received pharmacological (antiplatelet or anticoagulation) therapy. The primary outcome was new posterior circulation stroke within 30 days of injury as confirmed by imaging studies.

RESULTS

A total of 206 patients with blunt VAI were included. Median Injury Severity Score was 17 and 33 (16.0%) patients presented with Glasgow Coma Scale <8. The most common mechanism of injury was motor vehicle collision (58.7%). The injuries were bilateral in 38 (18.5%) patients and 73 (35.4%) suffered multisegmental injuries. The anatomic severity of injuries was Grade 1 = 38.8%, Grade 2 = 25.7%, Grade 3 = 4.9%, Grade 4 = 30.6%, and Grade 5 = 0.5%. There was no correlation between anatomic grade and stroke (P = 0.11) or initiation of pharmacologic therapy (P = 0.30). In total, 172 (84%) patients received pharmacological therapy with no differences in baseline characteristics between treated and untreated patients. Overall, the 30-day stroke rate was 1.9%. There was no difference in stroke rate between patients who received medical therapy versus those who did not (5.9% vs. 1.2%, P = 0.13). In subgroup analysis by injury severity, medical therapy did not improve stroke rates. Among patients treated with aspirin, there was no difference in stroke rate between doses of 81 vs. 325 mg (1.1% vs. 0%, P = 1).

CONCLUSIONS

Isolated VAI is associated with a very low risk of stroke and treatment with medical therapies including antiplatelet or anticoagulation does not improve risk of stroke.

Associations of Antithrombotic Timing and Regimen with Ischemic Stroke and Bleeding Complications in Blunt Cerebrovascular Injury

BACKGROUND

Blunt cerebrovascular injuries (BCVIs) are associated with long-term neurological effects. The first-line treatment for BCVIs is antithrombotics, but consensus on the optimal choice and timing of treatment is lacking.

METHODS

This was a retrospective study on patients aged at least 18 years admitted to 6 level 1 trauma centers between 1/1/2014 and 12/31/2017 with grade 1-4 BCVI and treated with antithrombotics. Differences in treatment practices were examined across the 6 centers. The primary outcome was ischemic stroke, and secondary outcomes were related to bleeding complications: blood transfusion and intracranial hemorrhage (ICH). Treatment characteristics examined were time to diagnosis and first computerized tomography angiography, time of total treatment course, time on each antithrombotic (anticoagulants, antiplatelets, combination), time from hospital arrival to antithrombotic initiation, and treatment interruption, i.e., treatment halted for a surgical procedure and restarted postoperatively. Chi-square, Fisher exact, Spearman's rank-order correlation, Wilcoxon rank-sum, Kruskal-Wallis, and Cox proportional hazards models with time-varying covariates were used to evaluate associations with the outcomes.

RESULTS

A total of 189 patients with BCVI were included. The median (IQR) time from arrival to antithrombotic initiation was 27 (8-61) hours, and 28% of patients had treatment interrupted. The ischemic stroke rate was 7.5% (n = 14), with most strokes (64%, n = 9) occurring between arrival and treatment initiation. Treatment interruption was associated with ischemic stroke (75% of patients with stroke had an interruption versus 24% of patients with no stroke; P < .01). Time on anticoagulants was not associated with ischemic stroke (P = .78), transfusion (P = .43), or ICH (P = .96). Similarly, time on antiplatelets (P = .54, P = .65, P = .60) and time on combination therapy (P = .96, P = .38, P = .57) were not associated with these outcomes.

CONCLUSIONS

The timing and consistency of antithrombotic administration are critical in preventing adverse outcomes in patients with BCVI. Most ischemic strokes in this study population occurred between arrival and antithrombotic initiation, representing events that may potentially be intervened upon by earlier treatment. Future studies should examine the safety of continuing treatment through surgical procedures.

Cervical Spine Fractures: Who Really Needs CT Angiography?

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Compare a novel two-step algorithm for indicating a computed tomography angiography (CTA) in the setting of a cervical spine fracture with established gold standard criteria.

SUMMARY OF BACKGROUND DATA

As CTA permits the rapid detection of blunt cerebrovascular injuries (BCVI), screening criteria for its use have broadened. However, more recent work warns of the potential for the overdiagnosis of BCVI, which must be considered with the adoption of broad criteria.

METHODS

A novel two-step metric for indicating CTA screening was compared with the American College of Surgeons guidelines and the expanded Denver Criteria using patients who presented with cervical spine fractures to a tertiary-level 1 trauma center from January 1, 2012 to January 1, 2016. The ability for each metric to identify BCVI and posterior circulation strokes that occurred during this period was assessed.

RESULTS

A total of 721 patients with cervical fractures were included, of whom 417 underwent CTAs (57.8%). Sixty-eight BCVIs and seven strokes were diagnosed in this cohort. All algorithms detected an equivalent number of BCVIs (52 with the novel metric, 54 with the ACS and Denver Criteria, P = 0.84) and strokes (7/7, 100% with the novel metric, 6/7, 85.7% with the ACS and Denver Criteria, P = 1.0). However, 63% fewer scans would have been needed with the proposed screening algorithm compared with the ACS or Denver Criteria (261/721, 36.2% of all patients with our criteria vs. 413/721, 57.3% with the ACS standard and 417/721, 57.8%) with the Denver Criteria, P < 0.0002 for each).

CONCLUSION

A two-step criterion based on mechanism of injury and patient factors is a potentially useful guide for identifying patients at risk of BCVI and stroke after cervical spine fractures. Further prospective analyses are required prior to widespread clinical adoption.

LEVEL OF EVIDENCE

4.

Blunt cerebrovascular injury in pediatric trauma: a national database study

OBJECTIVE

The incidence of blunt cerebrovascular injury (BCVI) has not been well characterized in the pediatric population. The goal of this study was to describe the incidence, patient characteristics, and risk factors for pediatric patients with cerebrovascular injuries.

METHODS

The authors collected data from the Kids' Inpatient Database (KID), a nationally representative database of pediatric admissions, for years 2000, 2003, 2006, 2009, and 2012.

RESULTS

Among an estimated 646,549 admissions for blunt trauma, 2150 were associated with BCVI, an overall incidence of 0.33%. The incidence of BCVI nearly doubled from 0.24% in 2000 to 0.49% in 2012. Patients 4 to 13 years of age were less likely to have BCVI than those in the youngest (0-3 years) and oldest age groups comprising adolescents (14-17 years) and young adults (18-20 years). BCVIs were associated with cervical (adjusted OR [aOR] 4.6, 95% CI 3.8-5.5), skull base (aOR 3.0, 95% CI 2.5-3.6), clavicular (aOR 1.4, 95% CI 1.1-1.8), and facial (aOR 1.2, 95% CI 1.0-1.5) fractures, as well as intracranial hemorrhage (aOR 2.7, 95% CI 2.2-3.2) and traumatic brain injury (aOR 2.0, 95% CI 1.7-2.3). Mechanism of injury was also independently associated with BCVI: motor vehicle collision (aOR 1.7, 95% CI 1.3-2.2) and struck pedestrian (aOR 1.4, 95% CI 1.0-1.9). Among pediatric patients with BCVI, 37.4% had cerebral ischemic infarction with an in-hospital mortality of 12.7%, and patients with stroke had 20% mortality.

CONCLUSIONS

The incidence of pediatric BCVI is increasing, likely due to increased use of screening, but remains lower than that in the adult population. Risk factors include the presence of cervical, facial, clavicular, and skull base fractures, similar to that of the adult population. Diagnosed BCVI is associated with a relatively high incidence of stroke with increased morbidity and mortality. The use of adult screening criteria is likely reasonable given the similarity in the risk factors identified in this study. Further studies are needed to investigate the role of treatment with antiplatelet agents or anticoagulation.

Aspirin for primary prevention of stroke in traumatic cerebrovascular injury: association with increased risk of transfusion

OBJECTIVE

Blunt traumatic extracranial carotid or vertebral artery injury (i.e., traumatic cerebrovascular injury [TCVI]) occurs in 1%-2% of all blunt trauma admissions, carries a 10% risk of thromboembolic ischemic stroke, and accounts for up to 9600 strokes annually in the US. Screening CT angiograms (CTAs) of patients with trauma has become ubiquitous in recent years, and patients with initially asymptomatic TCVI are commonly treated with antiplatelet agents to prevent stroke. Prophylaxis with antiplatelets is thought to be safer than anticoagulation, which carries a significant risk of hemorrhage in patients with trauma. However, the risk of hemorrhagic complications due to antiplatelets has not been assessed in this population.

METHODS

This is a retrospective cohort study of patients in whom a screening CTA was obtained after admission for blunt trauma at a Level 1 trauma center. Patients with CTAs indicating TCVI were treated routinely with 325 mg aspirin daily. The risk of transfusion > 24 hours after admission was compared according to CTA findings (CTA+ or CTA- for positive or negative findings, respectively) and aspirin treatment (ASA+ or ASA- for treatment or no treatment, respectively).

RESULTS

The mean overall transfusion amount (number of units of packed red blood cells [PRBCs]) was 0.9 ± 2.1 for CTA+/ASA+ patients (n = 196) and 0.3 ± 1.60 for CTA-/ASA- patients (n = 2290) (p < 0.0001). In adjusted models, the overall relative risk (RR) of PRBC transfusion was 1.70 (1.32-2.20) for CTA+/ASA+ patients compared with CTA-/ASA- patients. Among age groups, participants whose ages were 50-69 years had the greatest significantly elevated RR (1.71, 95% CI 1.08-2.72) for CTA+/ASA+ patients compared with CTA-/ASA- patients.

CONCLUSIONS

Treatment with aspirin for the prevention of stroke in patients with initially asymptomatic TCVI carries a significantly increased risk of PRBC transfusion. Future studies are needed to determine if this risk is offset by a reduced risk of ischemic stroke.

Treatment Practices and Outcomes After Blunt Cerebrovascular Injury in Children

BACKGROUND

Pediatric blunt cerebrovascular injury (BCVI) lacks accepted treatment algorithms, and postinjury outcomes are ill defined.

OBJECTIVE

To compare treatment practices among pediatric trauma centers and to describe outcomes for available treatment modalities.

METHODS

Clinical and radiographic data were collected from a patient cohort with BCVI between 2003 and 2013 at 4 academic pediatric trauma centers.

RESULTS

Among 645 pediatric patients evaluated with computed tomography angiography for BCVI, 57 vascular injuries (82% carotid artery, 18% vertebral artery) were diagnosed in 52 patients. Grade I (58%) and II (23%) injuries accounted for most lesions. Severe intracranial or intra-abdominal hemorrhage precluded antithrombotic therapy in 10 patients. Among the remaining patients, primary therapy was an antiplatelet agent in 14 (33%), anticoagulation in 8 (19%), endovascular intervention in 3 (7%), open surgery in 1 (2%), and no treatment in 16 (38%). Among 27 eligible grade I injuries, 16 (59%) were not treated, and the choice to not treat varied significantly among centers (P < .001). There were no complications from medical management. Glasgow Coma Scale (GCS) score <8 and increasing injury grade were predictors of injury progression (P = .001 and .004, respectively). Poor GCS score (P = .02), increasing injury grade (P = .03), and concomitant intracranial injury (P = .02) correlated with increased risk of mortality. Treatment modality did not correlate with progression of vascular injury or mortality.

CONCLUSION

Treatment of BCVI with antiplatelet or anticoagulant therapy is safe and may confer modest benefit. Nonmodifiable factors, including presenting GCS score, vascular injury grade, and additional intracranial injury, remain the most important predictors of poor outcome.

ABBREVIATIONS

ATT, antithrombotic therapyBCVI, blunt cerebrovascular injuryCTA, computed tomography angiographyGCS, Glasgow Coma Scale.

Contemporary Strategies in the Management of Civilian Neck Zone II Vascular Trauma

Neck trauma is the leading cause of death mainly in younger persons posing to surgeons the dilemma whether to proceed with reconstruction of vascular injuries either in the presence of coma or in severe neurological deficit. Vascular injuries in zone II predominate over the other injuries located in zones I/III of the neck. Conventional open repair of carotid injuries with primary closure or interposition grafting is always recommended due to the effective long-term results for penetrating injuries or for patients unfit for endovascular intervention. In cases of blunt trauma, anticoagulation or antiplatelet therapy should be administered first in neurologically stable patients. In case of worsening of the neurological status of the patient despite adequate anticoagulation endovascular means should be considered in cases of appropriate anatomy of the arterial trauma. We provide an update on penetrating/blunt trauma in zone II of the neck, giving emphasis on the anticoagulant and endovascular treatment.

Blunt Traumatic Extracranial Cerebrovascular Injury and Ischemic Stroke

Background

Ischemic stroke occurs in a significant subset of patients with blunt traumatic cerebrovascular injury (TCVI). The patients are victims of motor vehicle crashes, assaults or other high-energy collisions, and suffer ischemic stroke due to injury to the extracranial carotid or vertebral arteries.

Summary

An increasing number of patients with TCVI are being identified, largely because of the expanding use of computed tomography angiography for screening patients with blunt trauma. Patients with TCVI are particularly challenging to manage because they often suffer polytrauma, that is, numerous additional injuries including orthopedic, chest, abdominal, and head injuries. Presently, there is no consensus about optimal management.

Key Messages

Most literature about TCVI and stroke has been published in trauma, general surgery, and neurosurgery journals; because of this, and because these patients are managed primarily by trauma surgeons, patients with stroke due to TCVI have been essentially hidden from view of neurologists. This review is intended to bring this clinical entity to the attention of clinicians and investigators with specific expertise in neurology and stroke.

The Use of High-Risk Criteria in Screening Patients for Blunt Cerebrovascular Injury: A Survey

RATIONALE AND OBJECTIVES

Blunt cerebrovascular injury (BCVI) is uncommon, but delayed detection can have disastrous consequences. The Denver criteria are the most commonly used screening criteria. We aim to examine the utilization of screening criteria in the emergency department (ED) of our institution and assess whether patients with risk factors were imaged.

MATERIALS AND METHODS

A survey questionnaire was sent out to radiologists in a large academic institution. A search was performed in the database on the use of CT angiography (CTA) and MR angiography (MRA) among patients with risk factors in the last 11 years.

RESULTS

The survey was sent to 173 radiologists, with 41 responses (35 complete). Most of the physicians (30 out of 35) surveyed selected CTA as their preferred modality to screen for BCVI, whereas the remaining physicians selected MRA. None of the respondents reported routine use of Denver screening criteria or grading scale in their readouts. Only five respondents selected risk factors in the Denver criteria correctly. In the institution search, among the 1331 patients with blunt trauma and risk factors for BCVI, 537 underwent at least one angiographic study (40.3%). There was an increase in the screening rate after February 2010 in all risk factors, but only statistically significant among patients with foramen transversarium fractures and C1-C3 fractures.

CONCLUSIONS

Both the Denver screening criteria and grading scale of vascular injury have been underutilized in the ED for patients with risk factors. Greater awareness and utilization of imaging can potentially result in decreased incidence of subsequent stroke in patients with blunt injury.

Neurologic complications of polytrauma

Neurologic complications in polytrauma can be classified by etiology and clinical manifestations: neurovascular, delirium, and spinal or neuromuscular problems. Neurovascular complications include ischemic strokes, intracranial hemorrhage, or the development of traumatic arteriovenous fistulae. Delirium and encephalopathy have a reported incidence of 67-92% in mechanically ventilated polytrauma patients. Causes include sedation, analgesia/pain, medications, sleep deprivation, postoperative state, toxic ingestions, withdrawal syndromes, organ system dysfunction, electrolyte/metabolic abnormalities, and infections. Rapid identification and treatment of the underlying cause are imperative. Benzodiazepines increase the risk of delirium, and alternative agents are preferred sedatives. Pharmacologic treatment of agitated delirium can be achieved with antipsychotics. Nonconvulsive seizures and status epilepticus are not uncommon in surgical/trauma intensive care unit (ICU) patients, require electroencephalography for diagnosis, and need timely management. Spinal cord ischemia is a known complication in patients with traumatic aortic dissections or blunt aortic injury requiring surgery. Thoracic endovascular aortic repair has reduced the paralysis rate. Neuromuscular complications include nerve and plexus injuries, and ICU-acquired weakness. In polytrauma, the neurologic examination is often confounded by pain, sedation, mechanical ventilation, and distracting injuries. Regular sedation pauses for examination and maintaining a high index of suspicion for neurologic complications are warranted, particularly because early diagnosis and management can improve outcomes.

Traumatic Carotid Artery Dissection: A Different Entity without Specific Guidelines

According to literature data, there are no distinct guidelines regarding the proper diagnostic and therapeutic management of traumatic carotid artery dissection (TCAD). Although most of cases evaluated in research studies refer to spontaneous carotid artery dissection, traumatic cases demand special considerations as far as diagnosis and treatment are concerned. Although both types of dissection share some common characteristics, a patient with TCAD usually presents with several concomitant injuries as well as a higher bleeding risk, thus complicating decision making in such patients. Therefore, aim of this review is to present available data regarding epidemiology, clinical presentation, diagnostics and treatment strategy in cases with TCAD in order to produce useful conclusions for everyday clinical practice.

Evaluation for Blunt Cerebrovascular Injury: Review of the Literature and a Cost-Effectiveness Analysis

BACKGROUND AND PURPOSE

Evaluation for blunt cerebrovascular injury has generated immense controversy with wide variations in recommendations regarding the need for evaluation and the optimal imaging technique. We review the literature and determine the most cost-effective strategy for evaluating blunt cerebrovascular injury in trauma patients.

MATERIALS AND METHODS

A comprehensive literature review was performed with data extracted to create a decision-tree analysis for 5 different strategies: anticoagulation for high-risk (based on the Denver screening criteria) patients, selective DSA or CTA (only high-risk patients), and DSA or CTA for all trauma patients. The economic evaluation was based on a health care payer perspective during a 1-year horizon. Statistical analyses were performed. The cost-effectiveness was compared through 2 main indicators: the incremental cost-effectiveness ratio and net monetary benefit.

RESULTS

Selective anticoagulation in high-risk patients was shown to be the most cost-effective strategy, with the lowest cost and greatest effectiveness (an average cost of $21.08 and average quality-adjusted life year of 0.7231). Selective CTA has comparable utility and only a slightly higher cost (an average cost of $48.84 and average quality-adjusted life year of 0.7229). DSA, whether performed selectively or for all patients, was not optimal from both the cost and utility perspectives. Sensitivity analyses demonstrated these results to be robust for a wide range of parameter values.

CONCLUSIONS

Selective CTA in high-risk patients is the optimal and cost-effective imaging strategy. It remains the dominant strategy over DSA, even assuming a low CTA sensitivity and irrespective of the proportion of patients at high-risk and the incidence of blunt cerebrovascular injury in high-risk patients.

The limitations of using risk factors to screen for blunt cerebrovascular injuries: the harder you look, the more you find

Introduction

Blunt cerebrovascular injury (BCVI) is reported to occur in 1–2 % of blunt trauma patients. Clinical and radiologic risk factors for BCVI have been described to help identify patients that require screening for these injuries. However, recent studies have suggested that BCVI frequently occurs even in the absence of these risk factors. The purpose of this study was to determine the incidence of BCVI in blunt trauma patients without risk factors and whether these patients could be identified by a more liberal CTA screening protocol.

Methods

We conducted a retrospective cohort study of all blunt trauma patients seen between November 2010 and May 2014. In May 2012, a clinical practice guideline for CTA screening for BCVI was implemented. The records of all patients with BCVI were reviewed for the presence of risk factors for BCVI previously described in the literature.

Results

During the 43 month study period, 6,602 blunt trauma patients were evaluated, 2,374 prior to, and 4,228 after implementation of the clinical practice guideline. Nineteen percent of all blunt trauma patients underwent CTA of the neck after protocol implementation compared to only 1.5 % prior to protocol implementation (p = 0.001). As a result, a 5-fold increase in the identification of BCVI was observed (p = 0.00003). Thirty-seven percent of patients with BCVI identified with the enhanced CT screening protocol had none of the signs, symptoms, or risk factors usually associated with these injuries.

Conclusions

Our findings demonstrate that reliance on clinical or radiologic risk factors alone as indications for screening for BCVI is inadequate. We recommend routine CTA screening for BCVI in all patients who have sustained a mechanism of injury sufficient to warrant either a CT of the cervical spine or a CTA of the chest.

Predictors of Vertebral Artery Injury in Isolated C2 Fractures Based on Fracture Morphology Using CT Angiography

STUDY DESIGN

Retrospective database analysis.

OBJECTIVE

To determine C2 fracture patterns associated with vertebral artery injury (VAI) as assessed by computed tomography angiography.

SUMMARY OF BACKGROUND DATA

The incidence of C2 fracture hospitalizations has increased significantly in the last decade. The vertebral arteries are susceptible to injury as each courses through the C2 transverse foramen. Early screening for VAI to institute antithrombotic treatment is critical to prevent ischemic neurological sequelae. Imaging-based fracture classification schemes to determine which patterns are predictors of VAI in isolated C2 fractures using computed tomography angiography have not been described.

METHODS

Cervical spine computed tomographic (CT) scans at a level I trauma center were reviewed for isolated C2 fractures from 2004 to 2014 under institutional board review approval. Exclusion criteria included penetrating injury or additional cervical/occipital fractures. Fractures were classified using multiplanar CT scans into type I/II/IIa/III spondylolisthesis, type I/IIA/IIB/IIC/III dens, transverse foramen (displacement/comminution/intraforaminal fragments), and miscellaneous vertebral body fractures. Corresponding CT angiograms were assessed for VAI on the basis of the Denver grading criteria. Fisher exact test and Student t test were performed to determine predictors of VAI on the basis of fracture type.

RESULTS

Sixty-seven patients met inclusion criteria. Fracture pattern analysis revealed that the majority were dens fractures (50.8%) and traumatic spondylolisthesis (41.8%); 29.9% had miscellaneous coronal/sagittal fractures and 22.4% were a combination.VAI was identified in 37.3% of patients with isolated C2 fractures, and 88% of patients had transverse foramen involvement. Fracture patterns significantly associated with VAI were type III dens and transverse foramen fractures with intraforaminal fragments, with or without comminution.

CONCLUSION

The C2 fracture pattern most associated with VAI was comminuted transverse foramen fracture with intraforaminal fragments. Transverse foramen fracture alone was not found to be significant. These results help stratify patients with isolated C2 fractures who are at high VAI risk and should be further evaluated with computed tomography angiography.

LEVEL OF EVIDENCE

3.

Carotid and vertebral injury study (CAVIS) technique for characterization of blunt traumatic aneurysms with reliability assessment

Traumatic aneurysms occur in up to 20% of blunt traumatic extracranial carotid artery injuries. Currently there is no standardized method for characterization of traumatic aneurysms. For the carotid and vertebral injury study (CAVIS), a prospective study of traumatic cerebrovascular injury, we established a method for aneurysm characterization and tested its reliability. Saccular aneurysm size was defined as the greatest linear distance between the expected location of the normal artery wall and the outer edge of the aneurysm lumen ("depth"). Fusiform aneurysm size was defined as the "depth" and longitudinal distance ("length") paralleling the normal artery. The size of the aneurysm relative to the normal artery was also assessed. Reliability measurements were made using four raters who independently reviewed 15 computed tomographic angiograms (CTAs) and 13 digital subtraction angiograms (DSAs) demonstrating a traumatic aneurysm of the internal carotid artery. Raters categorized the aneurysms as either "saccular" or "fusiform" and made measurements. Five scans of each imaging modality were repeated to evaluate intra-rater reliability. Fleiss's free-marginal multi-rater kappa (κ), Cohen's kappa (κ), and interclass correlation coefficient (ICC) determined inter- and intra-rater reliability. Inter-rater agreement as to the aneurysm "shape" was almost perfect for CTA (κ = 0.82) and DSA (κ = 0.897). Agreements on aneurysm "depth," "length," "aneurysm plus parent artery," and "parent artery" for CTA and DSA were excellent (ICC > 0.75). Intra-rater agreement as to aneurysm "shape" was substantial to almost perfect (κ > 0.60). The CAVIS method of traumatic aneurysm characterization has remarkable inter- and intra-rater reliability and will facilitate further studies of the natural history and management of extracranial cerebrovascular traumatic aneurysms.

Posterior circulation infarction in patients with traumatic cervical spinal cord injury and its relationship to vertebral artery injury

STUDY DESIGN

Prospective study.

OBJECTIVE

To ascertain the prevalence of posterior circulation stroke in traumatic chronic spinal cord injured (SCI) patients and associated traumatic vertebral artery injuries (VAI).

METHODS

All adult patients with cervical SCI and American Spinal Injury Association Impairment Scale (AIS) grade A or B referred for follow-up magnetic resonance imaging of their spinal cord were invited to take part in the study between January 2010 and December 2012 at the National Spinal Injury Centre. Two additional sequences were added to the existing imaging protocol to evaluate the brain and vertebral arteries.

RESULTS

Ninety-eight patients were recruited. All imaging were analysed independently by three consultant radiologists. Posterior circulation infarcts were noted in seven (7%) patients. Significant VAI was noted in 13 patients (13%) with 10 occlusions and 3 with high-grade stenosis. However, only one patient had co-existent posterior circulation infarct and significant VAI.

CONCLUSION

There is an increased prevalence of posterior circulation infarction in SCI patients. The relationship with associated traumatic VAI requires further investigation.

Management of carotid artery trauma

With increased awareness and liberal screening of trauma patients with identified risk factors, recent case series demonstrate improved early diagnosis of carotid artery trauma before they become problematio. There remains a need for unified screening criteria for both intracranial and extracranial carotid trauma. In the absence of contraindications, antithrombotic agents should be considered in blunt carotid artery injuries, as there is a significant risk of progression of vessel injury with observation alone. Despite CTA being used as a common screening modality, it appears to lack sufficient sensitivity. DSA remains to be the gold standard in screening. Endovascular techniques are becoming more widely accepted as the primary surgical modality in the treatment of blunt extracranial carotid injuries and penetrating/blunt intracranial carotid lessions. Nonetheless, open surgical approaches are still needed for the treatment of penetrating extracranial carotid injuries and in patients with unfavorable lesions for endovascular intervention.

Blunt cerebrovascular injury screening guidelines: what are we willing to miss?

BACKGROUND

Blunt cerebrovascular injury (BCVI) is reported to occur in approximately 2% of blunt trauma patients, with a stroke rate of up to 20%. Guidelines for BCVI screening are based on clinical and radiographic findings. We hypothesized that liberal screening of the neck vasculature, as part of initial computed tomographic (CT) imaging in blunt trauma patients with significant mechanisms of injury, identifies BCVI that may go undetected.

METHODS

As per protocol, patients at risk for significant injuries undergo a noncontrast head CT scan followed by a multislice CT scan (40-slice or 64-slice) incorporating an intravenous contrast-enhanced pass from the circle of Willis through the pelvis (whole-body CT [WBCT] scan). The trauma registry was retrospectively reviewed, and all patients with BCVI from 2009 to 2012 were analyzed. Patients undergoing WBCT scan were then identified, and records were reviewed for BCVI indicators (skull base fracture, cervical spine injury, displaced facial fracture, mandible fracture, Glasgow Coma Scale score ≤ 8, flexion mechanism, hard signs of neck vascular injury, or focal neurologic deficit).

RESULTS

Of 16,026 patients evaluated during the study period, 256 (1.6%) were diagnosed with BCVI. The population consisted of 185 patients with suspected BCVI after WBCT scan. One hundred twenty-nine patients (70%) had at least one indicator for BCVI screening, while 56 (30%) had no radiographic or clinical risk factors; 48 of the 56 patients underwent confirmatory CT angiography of the neck within 71 hours of initial WBCT scan, with 35 patients having 45 injuries.

CONCLUSION

More liberalized screening for BCVI during initial CT imaging in trauma patients clinically judged to have sufficient mechanism is warranted. Using current BCVI screening guidelines leads to missed BCVI and risk of stroke.

LEVEL OF EVIDENCE

Diagnostic study, level III.

Blunt cerebrovascular injury screening with 64-channel multidetector computed tomography: more slices finally cut it

BACKGROUND

Aggressive screening to diagnose blunt cerebrovascular injury (BCVI) results in early treatment, leading to improved outcomes and reduced stroke rates. While computed tomographic angiography (CTA) has been widely adopted for BCVI screening, evidence of its diagnostic sensitivity is marginal. Previous work from our institution using 32-channel multidetector CTA in 684 patients demonstrated an inadequate sensitivity of 51% (Ann Surg. 2011,253: 444-450). Digital subtraction angiography (DSA) continues to be the reference standard of diagnosis but has significant drawbacks of invasiveness and resource demands. There have been continued advances in CT technology, and this is the first report of an extensive experience with 64-channel multidetector CTA.

METHODS

Patients screened for BCVI using CTA and DSA (reference) at a Level 1 trauma center during the 12-month period ending in May 2012 were identified. Results of CTA and DSA, complications, and strokes were retrospectively reviewed and compared.

RESULTS

A total of 594 patients met criteria for BCVI screening and underwent both CTA and DSA. One hundred twenty-eight patients (22% of those screened) had 163 injured vessels: 99 (61%) carotid artery injuries and 64 (39%) vertebral artery injuries. Sixty-four-channel CTA demonstrated an overall sensitivity per vessel of 68% and specificity of 92%. The 52 false-negative findings on CTA were composed of 34 carotid artery injuries and 18 vertebral artery injuries; 32 (62%) were Grade I injuries. Overall, positive predictive value was 36.2%, and negative predictive value was 97.5%. Six procedure-related complications (1%) occurred with DSA, including two iatrogenic dissections and one stroke.

CONCLUSION

Sixty-four-channel CTA demonstrated a significantly improved sensitivity of 68% versus the 51% previously reported for the 32-channel CTA (p = 0.0075). Sixty-two percent of the false-negative findings occurred with low-grade injuries. Considering complications, cost, and resource demand associated with DSA, this study suggests that 64-channel CTA may replace DSA as the primary screening tool for BCVI.

LEVEL OF EVIDENCE

Diagnostic study, level III.

Variability in evolution and course of gunshot injuries to the neck and impact on management. A case report

This study reports the differences in evolution and course of multiple pseudoaneurysms (PAs) and an axillary arteriovenous fistula (AVF) after penetrating vascular trauma due to shotgun injury to the head and neck. We describe the unusual case of a young man who, following penetrating shotgun injuries to the head and neck, developed multiple PAs of the common carotid, vertebral and superficial temporal arteries as well as an axillary AVF. Serial angiographic follow-up studies documented differences in time of occurrence, evolution and course of these lesions. This allowed for tailored management using endovascular (AVF, superficial temporal artery PAs) and conservative (carotid and vertebral PAs) treatment. No complication occurred and complete cure of all lesions was achieved and documented after seven months. Time of occurrence, evolution and regression of penetrating vascular injuries can differ significantly even in the same patient. Close angiographic follow-up helps not only detect a lesion with delayed occurrence, but also provides a practical basis for decision-making for optimal therapeutic management.

Imaging of blunt vascular neck injuries: a clinical perspective

OBJECTIVE

We will review the common injuries and anatomic distributions of blunt cerebrovascular injuries (BCVIs) of the neck, explain the grading criteria, and discuss the corresponding management. Artifacts associated with BCVI on CT will also be examined.

CONCLUSION

Identifying common injury patterns and anatomic distributions associated with BCVI can help decide the grade and management earlier and reduce the risk for potential complications. Recognizing the common artifacts associated with BCVI helps the reader successfully recognize a true BCVI.

Combined tracheoesophageal transection after blunt neck trauma

Survival following tracheoesophageal transection is uncommon. Establishing a secure airway has the highest priority in trauma management. Understanding the mechanism of the incident can be a useful adjunct in predicting the likelihood and severity of specific anatomical patterns of injuries. We discuss published literature on combined tracheoesophageal injuries after blunt neck trauma and their outcome. A search of MEDLINE for papers published regarding tracheoesophageal injury was made. The literature search identified 14 such articles referring to a total of 27 patients. Age ranged from 3-73 years. The mechanism of injury was secondary to a rope/wire in 33%, metal bar in 4% of cases and unspecified in 63%. All of the patients were managed surgically. A number of tissues were used to protect the anastomosis including pleural and sternocleidomastoid muscle flaps. There were no reported mortalities. Patients with combined tracheoesophageal injury after blunt neck trauma require acute management of airway along with concomitant occult injuries.

Diagnostic accuracy of computed tomographic angiography for blunt cerebrovascular injury detection in trauma patients: a systematic review and meta-analysis

OBJECTIVE

To compare the diagnostic accuracy of computed tomographic angiography (CTA) with digital subtraction angiography (DSA) for blunt cerebrovascular injury (BCVI) detection in trauma patients.

BACKGROUND

Controversy exists as to whether the diagnostic performance of CTA compares favorably with the reference-standard, DSA.

METHODS

We searched electronic databases (1950 to May 22, 2012), article bibliographies, conference proceedings (2008-2011), and clinical trial registries for studies comparing the accuracy of CTA with DSA for BCVI detection in trauma patients. Pooled estimates of sensitivity, specificity, and positive and negative likelihood ratios were calculated using bivariate random effects models.

RESULTS

Eight studies that examined 5704 carotid or vertebral arteries in 1426 trauma patients met inclusion criteria. The pooled sensitivity and specificity for BCVI detection with CTA versus DSA was 66% (95% CI, 49%-79%; I = 80.4%) and 97% (95% CI, 91%-99%; I = 94.6%), respectively. Corresponding pooled positive and negative likelihood ratios were 20.0 (95% CI, 6.9-58.4; I = 87.7%) and 0.35 (95% CI, 0.22-0.56; I = 74.9%), respectively. Although pooled sensitivity varied with the number of available CT slices, the training of interpreting radiologists, and in a pattern suggestive of differences in diagnostic threshold for judging CTA positivity, it remained 80% or less among studies that used scanners with 16 or more slices per rotation and where the CTA was read by neuroradiologists.

CONCLUSIONS

Existing evidence suggests that the diagnostic performance of CTA varies considerably across studies, likely due to an implicit variation in diagnostic threshold across trauma centers. Moreover, although CTA appears to lack sensitivity to adequately rule out BCVI, it may be useful to rule in BCVI among trauma patients with a high pretest probability of injury.

Blunt cerebrovascular injury: diagnosis at whole-body MDCT for multi-trauma

Purpose

To analyse the prevalence of blunt cerebrovascular injuries (BCVIs) in multi-trauma patients by means of a post-contrast acquisition of neck vessels included into the whole-body multi-detector computed tomography (MDCT) protocol performed at admission and to correlate it with the presence of risk factors (Memphis approach).

Materials and methods

A retrospective study was undertaken for the period January 2005 to November 2011, involving 976 multi-trauma patients. Post-contrast images of neck vessels in MDCT scan were evaluated by two experienced radiologists; carotid, vertebral and basilar arteries were rated according to the Biffl classification. The presence of clinical and/or CT risk factors for BCVI was assessed.

Results

BCVI were present in 32/976 (3.3 %) multi-trauma patients. Risk factors for BCVI were present in 247/976 (25.3 %) patients. The group of patients presenting risk factors showed a significantly higher prevalence of cerebrovascular injuries (8.1 %) compared with the group of patients without risk factors (1.6 %) (p = 0.009); however, 12/32 (37.5 %) patients presenting BCVI did not show any of the risk factors proposed by the Memphis group.

Conclusion

An investigation for the presence of BCVI should be performed on all multi-trauma patients despite the absence of clinical-radiological risk factors.

Key Points

BCVIs are present in 3.3 % of multi-trauma patients.

BCVIs are significantly associated to the Memphis risk factors.

Of the multi-trauma patients affected by BCVIs, 37.5 % do not show clinical-radiological risk factors.

A screening for BCVI should be performed on all multi-trauma patients.

Timing and mechanism of ischemic stroke due to extracranial blunt traumatic cerebrovascular injury

OBJECT

Extracranial cerebrovascular injury is believed to be an important cause of neurological injury in patients who have suffered blunt trauma. The authors sought to determine the timing and mechanisms of ischemic stroke in patients who suffered traumatic cerebrovascular injury (TCVI).

METHODS

This is a prospective study of all patients with TCVI who were admitted to a Level I trauma center during a 28-month period. All patients who suffered blunt trauma and had risk factors for TCVI underwent screening CT angiography (CTA) of the head and neck on admission. All patients with either an ischemic stroke or CTA suggesting TCVI underwent confirmatory digital subtraction angiography (DSA). Patients with DSA-confirmed TCVI were treated with 325 mg aspirin daily; all patients were observed during their hospitalization for the occurrence of new ischemic stroke. In addition, a subset of patients with TCVI underwent transcranial Doppler ultrasonography monitoring for microembolic signals.

RESULTS

A total of 112 patients had CTA findings suggestive of TCVI; 68 cases were confirmed by DSA. Overall, 7 patients had an ischemic stroke in the territory of the affected artery prior to or during admission. Four of the patients had their event prior to diagnosis with CTA and 2 occurred prior to DSA. In 1 patient the ischemic stroke was found to be due to an extracranial atherosclerotic carotid plaque, and this patient was excluded from further analysis. All patients with ischemic stroke had brain CT findings consistent with an embolic mechanism. Two (8.7%) of 23 monitored patients with TCVI had microembolic signals on transcranial Doppler ultrasonography.

CONCLUSIONS

Most ischemic strokes due to TCVI are embolic in nature and occur prior to screening CTA and initiation of treatment with aspirin.

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

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.