Denver screening protocol for blunt cerebrovascular injury reduces the use of multi-detector computed tomography angiography

Traumatic Cervical Cerebrovascular Injury and the Role of CTA: AJR Expert Panel Narrative Review

Traumatic cerebrovascular injury (CVI) involving the cervical carotid and vertebral arteries is rare but can lead to stroke, hemodynamic compromise, and mortality in the absence of early diagnosis and treatment. The diagnosis of both blunt cerebrovascular injury (BCVI) and penetrating CVI is based on cerebrovascular imaging. The most commonly used screening criteria for BCVI include the expanded Denver criteria and the Memphis criteria, each providing varying thresholds for subsequent imaging. Neck CTA has supplanted catheter-based digital subtraction angiography as the preferred screening modality for CVI in patients with trauma. This AJR Expert Panel Narrative Review describes the current state of CTA-based cervical imaging in trauma. We review the most common screening criteria for BCVI, discuss BCVI grading scales that are based on neck CTA, describe the diagnostic performance of CTA in the context of other imaging modalities and evolving treatment strategies, and provide a practical guide for neck CTA implementation.

A C1 Jefferson Fracture With Vertebral Artery Occlusion and Cerebellar Infarction: A Case Report

Jefferson fracture is a C1 fracture, which happens when an axial load is from the occiput downward to the C1 ring. Usually, it causes outward displacement of the C1 arch, which can injure the vertebral artery. We present a Jefferson fracture with vertebral artery injury, resulting in an asymptomatic ischemic stroke of the left cerebellum. Usually, vertebral artery injuries are asymptomatic since the contralateral vertebral artery and the collateral arteries will adequately supply the cerebellum. Vertebral artery injury (VAI) is typically treated with conservative management with anticoagulants and antiplatelet therapy.

The Utility of a Screening Neck Computed Tomographic Angiogram in Blunt Trauma Patients Presenting With a Seat Belt Sign in the Absence of Associated Risk Factors

OBJECTIVE

Blunt cerebrovascular injuries (BCVI) of the neck are a common cause for concern after blunt trauma. The purpose of this article is to demonstrate whether patients with a cervical seat belt sign in the absence of associated high-risk injuries or neurological symptoms are at an increased risk for developing a clinically significant vascular injury and therefore require a screening neck computed tomographic angiography (CTA).

METHODS

A retrospective review was performed of patients who presented after motor vehicle collision and received a neck CTA for an indication of "seat belt sign." Imaging was reviewed to determine the vascular injury grade, associated injuries, and, if available, follow-up imaging was reviewed to assess for interval change or resolution. The patients were split into 2 groups. Group 1 included patients without high-risk injuries, and group 2 included patients with high-risk injuries.

RESULTS

In group 1, 6 (2.9%) of 208 patients had BCVI. In group 2, 7 (18.9%) of 37 patients had BCVI. Patients in group 2 were 6.5 times more likely to suffer BCVI compared with group 1 (P < 0.001). No patient in group 1 was ever symptomatic, and only 1 (0.5%) patient underwent interventional treatment.

CONCLUSIONS

Patients presenting after blunt trauma with a seat belt sign and no other high-risk injuries as laid out by screening criteria demonstrate a low probability of BCVI and an even lower likelihood of adverse outcome.

Traumatic vertebral artery injuries in the geriatric population: a retrospective cohort study

OBJECTIVE

Traumatic vertebral artery injuries (TVAIs) are a common finding in cervical spine trauma and can predispose patients to posterior circulation infarction. While extensive research has been conducted regarding the management and criteria for imaging in patients with suspected blunt vascular injury, little research has been conducted highlighting these injuries in the geriatric population.

METHODS

The authors performed a retrospective review of all patients evaluated at a level 1 trauma center and found to have TVAIs between January 1, 2010, and January 1, 2018. Biometric, clinical, and imaging data were obtained from a trauma registry database. Patients were divided into 2 groups on the basis of age, a geriatric group (age ≥ 65 years) and an adult group (age 18 to < 65 years). Variables evaluated included type of trauma, mortality, Injury Severity Score (ISS), and ICU length of stay. The Student t-test was used for continuous variables, and Pearson's chi-square test was used for categorical variables.

RESULTS

Of the 2698 of patients identified with traumatic cervical spine injuries, 103 patients demonstrated evidence of TVAI. Of these patients, 69 were < 65 and 34 were ≥ 65 years old at the time of their trauma. There was no difference in the incidence of TVAIs between the 2 groups. The ICU length of stay (4.71 vs 4.32 days, p > 0.05), hospital length of stay (10.71 vs 10.72 days, p > 0.05), and the ISS (21.50 vs 21.32, p > 0.05) did not differ significantly between the 2 groups. Mortality was significantly higher in the geriatric group, occurring in 9 of 34 patients (26.5%) compared with only 3 of 69 patients (4.4%) in the adult group (p < 0.001). Ground-level falls were the most common inciting event in the geriatric group (44% vs 14.5%, p < 0.001), whereas motor vehicle accidents were the most common etiology in the younger population (72.5% vs 38.2%, p < 0.001). Incidence of ischemic stroke did not vary significantly between the 2 groups (p > 0.05).

CONCLUSIONS

TVAI in the older adult population is associated with a significantly greater risk of mortality than in the younger adult population, despite the 2 groups having similar ISSs. Additionally, low-velocity mechanisms of injury, such as ground-level falls, are a greater risk factor for acquired TVAI in older adults than in younger adults, in whom it is a significantly less common etiology.

Blunt vertebral artery injury in occipital condyle fractures

OBJECTIVEA shifting emphasis on efficient utilization of hospital resources has been seen in recent years. However, reduced screening for blunt vertebral artery injury (BVAI) may result in missed diagnoses if risk factors are not fully understood. The authors examined the records of blunt trauma patients with fractures near the craniocervical junction who underwent CTA at a single institution to better understand the risk of BVAI imposed by occipital condyle fractures (OCFs).METHODSThe authors began with a query of their prospectively collected trauma registry to identify patients who had been screened for BVAI using ICD-9-CM diagnostic codes. Grade and segment were recorded in instances of BVAI. Locations of fractures were classified into 3 groups: 1) OCFs, 2) C1 (atlas) fractures, and 3) fractures of the C2-6 vertebrae. Univariate and multivariate analyses were performed to identify any fracture types associated with BVAI.RESULTSDuring a 6-year period, 719 patients underwent head and neck CTA following blunt trauma. Of these patients, 147 (20%) had OCF. BVAI occurred in 2 of 43 patients with type I OCF, 1 of 42 with type II OCF, and in 9 of 62 with type III OCF (p = 0.12). Type III OCF was an independent risk factor for BVAI in multivariate modeling (OR 2.29 [95% CI 1.04-5.04]), as were fractures of C1-6 (OR 5.51 [95% CI 2.57-11.83]). Injury to the V4 segment was associated with type III OCF (p < 0.01).CONCLUSIONSIn this study, the authors found an association between type III OCF and BVAI. While further study may be necessary to elucidate the mechanism of injury in these cases, this association suggests that thorough cerebrovascular evaluation is warranted in patients with type III OCF.

Best practice guidelines for blunt cerebrovascular injury (BCVI)

Blunt cerebrovascular injury (BCVI) is a non-penetrating injury to the carotid and/or vertebral artery that may cause stroke in trauma patients. Historically BCVI has been considered rare but more recent publications indicate an overall incidence of 1-2% in the in-hospital trauma population and as high as 9% in patients with severe head injury. The indications for screening, treatment and follow-up of these patients have been controversial for years with few clear recommendations. In an attempt to provide a clinically oriented guideline for the handling of BCVI patients a working committee was created. The current guideline is the end result of this committees work. It is based on a systematic literature search and critical review of all available publications in addition to a standardized consensus process. We recommend using the expanded Denver screening criteria and CT angiography (CTA) for the detection of BCVI. Early antithrombotic treatment should be commenced as soon as considered safe and continued for at least 3 months. A CTA at 7 days to confirm or discard the diagnosis as well as a final imaging control at 3 months should be performed.

Management of Major Vascular Injuries: Neck, Extremities, and Other Things that Bleed

Vascular injuries represent a significant burden of mortality and disability. Blunt injuries to the neck vessels can present with signs of stroke either immediately or in a delayed fashion. Most injuries are detected with computed tomography angiography and managed with either antiplatelet medications or anticoagulation. In contrast, patients with penetrating injuries to the neck vessels require airway management, hemorrhage control, and damage control resuscitation before surgical repair. The keys to diagnosis and management of peripheral vascular injury include early recognition of the injury; hemorrhage control with direct pressure, packing, or tourniquets; and urgent surgical consultation.

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.

Temporary vertebral artery occlusion after C3 fracture dislocation injury and spontaneous resolution following reduction and instrumented fusion: case report and literature review

Vertebral artery injuries as a result of blunt trauma can result in vertebrobasilar strokes. Typical treatment of such an injury includes early anticoagulation to prevent cerebral ischemic events due to vessel occlusion or embolism. We present a case of cervical fracture-dislocation injury and compression/occlusion of the right vertebral artery, which spontaneously resolved following surgical reduction and fusion. Postoperative cerebral angiography showed no evidence of vertebral artery stenosis, and systemic anticoagulation was discontinued. This case shows that vertebral artery occlusion can resolve spontaneously after fracture reduction, and cerebral angiography should play a role in assessing these complicated traumatic injuries.

Expanded screening criteria for blunt cerebrovascular injury: a bigger impact than anticipated

BACKGROUND

We implemented expanded screening criteria for blunt cerebrovascular injuries (BCVIs) in an attempt to capture the remaining 20% of patients not historically identified with earlier protocols. We hypothesized that these expanded criteria would capture the additional 20% of BCVI patients not previously identified.

METHODS

Screening criteria for BCVI were expanded in 2011 after identifying new injury patterns. The study population included 4 years prior (2007 to 2010; classic) and following (2011 to 2014; expanded) implementation of expanded criteria.

RESULTS

BCVIs were identified in 386 patients: 150 during the classic period (2.36% incidence) and 236 in the expanded period (2.99% incidence). In the expanded period, 155 patients were imaged based on classic screening criteria, 62 on expanded criteria (21 complex skull fractures, 20 upper rib fractures, 6 mandible fractures, 2 scalp degloving, 1 great vessel injury, and 12 combination), and 19 for other injuries and symptoms.

CONCLUSIONS

There was a significant increase in the identification of BCVI following the adoption of expanded screening criteria, resulting in a substantial reduction of missed injuries. Expanded criteria should be adopted when screening for BCVI.

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.

Core curriculum illustration: blunt cerebrovascular injury

This is the 15th installment of a series that will highlight one case per publication issue from the bank of cases available online as part of the American Society of Emergency Radiology (ASER) educational resources. Our goal is to generate more interest in and use of our online materials. To view more cases online, please visit the ASER Core Curriculum and Recommendations for Study online at http://www.aseronline.org/curriculum/toc.htm .