Risk factors for stroke in penetrating cerebrovascular injuries.

OBJECTIVE: Penetrating cerebrovascular injuries (PCVI) are associated with a high incidence of mortality and neurological events. The optimal treatment strategy of PCVI, especially when damage control measures are required, remains controversial. The aim of this study was to describe the management of PCVI and patient outcomes at a level 1 trauma center where vascular injuries are managed predominantly by trauma surgeons. METHODS: An institutional trauma registry was queried for patients with PCVI from 2011 to 2021. Patients with common carotid artery (CCA), internal carotid artery (ICA), or vertebral artery injuries were included for analysis. The primary outcome was in-hospital stroke. The secondary outcomes were in-hospital mortality and in-hospital stroke or death. A subgroup analysis was completed of arterial repair (primary repair or interposition graft) vs ligation or embolization vs temporary intravascular shunting at the index procedure. RESULTS: We analyzed 54 patients with PCVI. Overall, the in-hospital stroke rate was 17% and in-hospital mortality was 26%. Twenty-one patients (39%) underwent arterial interventions for PCVI. Ten patients underwent arterial repair, six patients underwent ligation or embolization, and five patients underwent intravascular shunting as a damage control strategy with a plan for delayed repair. The rate of in-hospital stroke was 30% after arterial repair, 0% after arterial ligation or embolization, and 80% after temporary intravascular shunting. There was a significant difference in the stroke rate between the three subgroups (P = .015). Of the 32 patients who did not have an intervention to the CCA, ICA, or vertebral artery, 1 patient with ICA occlusion and 1 patient with CCA intimal injury developed in-hospital stroke. The mortality rate was 0% after arterial repair, 50% after ligation or embolization, and 60% after intravascular shunting. The rate of stroke or death was 30% in the arterial repair group, 50% in the ligation or embolization group, and 100% in the temporary intravascular shunting group. CONCLUSIONS: High rates of stroke and mortality were seen in patients requiring damage control after PCVI. In particular, temporary intravascular shunting was associated with a high incidence of in-hospital stroke and a 100% rate of stroke or death. Further investigation is needed into the factors related to these finding and whether the use of temporary intravascular shunting in PCVI is an advisable strategy.

The role of number of affected vessels on radiologic and clinical outcomes of patients with blunt cerebrovascular injury.

OBJECTIVE: There is a lack of data on the role of characteristics of injured vessels on the outcomes of patients with blunt cerebrovascular injuries (BCVIs). The aim of this study was to assess the effect of the number (single vs multiple) of injured vessels on outcomes. METHODS: This is a retrospective study at two American College of Surgeons Level I trauma centers (2017-2021). Adult (>16 years) trauma patients with BCVIs are included. Injuries were graded by the Denver Scale based on the initial computed tomography angiography (CTA). Early repeat CTA was performed 7 to 10 days after diagnosis. Patients were stratified by the number (single vs multiple) of the involved vessels. Outcomes included progression of BCVIs on repeat CTA, stroke, and in-hospital mortality attributable to BCVIs. Multivariable regression analyses were performed to identify the association between the number of injured vessels and outcomes. RESULTS: A total of 491 patients with 591 injured vessels (285 carotid and 306 vertebral arteries) were identified. Sixty percent were male, the mean age was 44 years, and the median Injury Severity Score was 18 (interquartile range, 11-25). Overall, 18% had multiple-vessel injuries, 16% had bilateral vessel injuries, and 3% had multiple injuries on the same side. The overall rates of progression to higher-grade injuries, stroke, and mortality were 23%, 7.7%, and 8.8%, respectively. On uni- and multivariable analyses, multiple BCVIs were associated with progression to higher-grade injuries on repeat imaging, stroke, and mortality compared with single-vessel injuries. CONCLUSIONS: BCVIs with multiple injured vessels are more likely to progress to higher grades on repeat CTA, with multiple injuries independently associated with worse clinical outcomes, compared with those with single injuries. These findings highlight the importance of incorporating the number of injured vessels in clinical decision-making and in defining protocols for repeat imaging.

Medical Management of Traumatic Vertebral Artery Injury Is Safe Regardless of the Severity of Injury.

BACKGROUND: Management of traumatic vertebral artery injury (VAI) remains under debate. Current consensus reserves surgical or endovascular management for high-grade injury in order to prevent stroke. We sought to evaluate the factors that influence posterior fossa stroke outcomes following traumatic VAI. METHODS: A search of the prospectively maintained PROOVIT trauma registry of patients older than 18 years of age with a diagnosis of VAI was performed at a level 1 trauma center from 2013 to 2019. Patient demographics, type of injury, the timing of presentation, Biffl Classification of Cerebrovascular Injury Grade score, medical management, procedural interventions, and stroke outcomes were analyzed. RESULTS: VAIs were identified in 66 trauma patients were identified out of 14,323 patients entered into the PROOVIT registry. The dominant mechanism was blunt injury (91.5% vs. 8.5%, blunt versus penetrating). Nine patients presented with symptomatic ipsilateral posterior circulation strokes visible on imaging. The average Biffl classification grade was similar between the stroke and nonstroke groups (2.0 vs. 1.5; P = 0.39). The average injury severity score (ISS) between stroke and nonstroke groups was also similar (9.0 vs. 14.0; P = 0.35). All 9 patients in the stroke group had magnetic resonance imaging verification of their infarct within an average of 21.2 hr from presentation. In the stroke group, 1 patient underwent diagnostic angiography but had no intervention. In the nonstroke group, all were treated with medical management alone and none underwent vertebral artery intervention. During a mean follow-up of 14.5 months, no patients experienced a new neurological deficit. CONCLUSIONS: The severity of VAI by Biffl grading and ISS are not associated with ischemic stroke at presentation following VAI. Medical management of VAI appears safe regardless of Biffl and ISS staging in this trauma population. Neurological changes related to embolic stroke were generally appreciated on presentation. Conservative medical management was sufficient to protect from secondary neurological deficit regardless of index vertebral injury.

[Vertebral artery dissection during traumatic injury of the cervical spine, two case reports]. / Nyaki gerinc traumás sérülése során jelentkezo arteria vertebralis dissectio, két esetbemutatás.

If severe cervical spinal cord injury or severe cervical vertebral fracture, subluxation or luxation is confirmed, 20-40% of the cases have vertebral artery dissection or occlusion. These can be asymptomatic, but can cause additional neurological damage in addition to cervical myelon and cervical nerve root symptoms. Vertebral artery dissection can be caused by direct injuries, stab wounds or gunshot wounds. Indirect vertebral artery dissection can occur at the same time as subluxation, luxation, or complex fractures of the cervical vertebra. CTA is the examination procedure of choice. In many cases, digital subtaction angiography examination and, if necessary, neurointerventional treatment must precede open neurosurgery. In our report, in the first patient, complete luxation of the C.VI vertebra caused unilateral vertebral artery 2-segment dissection-occlusion, while in our second patient, a stab injury caused direct vertebral artery compression and dissection. The occlusion of the vertebral artery did not cause neurological symptoms in any of the cases. In both of our cases, parent vessel occlusion was performed at the level of the vertebral artery injury before the neurosurgical operation.

Trauma mechanisms and patterns of blunt cervical vascular injury: A descriptive study using a nationwide trauma registry.

OBJECTIVE: Blunt cervical vascular injury (BCVI) is a non-penetrating trauma to the carotid and/or vertebral vessels following a direct injury to the neck or by the shearing of the cervical vessels. Despite its potentially life-threatening nature, important clinical features of BCVI such as typical patterns of co-occurring injuries for each trauma mechanism are not well known. To address this knowledge gap, we described the characteristics of patients with BCVI to identify the pattern of co-occurring injuries by common trauma mechanisms. METHODS: This is a descriptive study using a Japanese nationwide trauma registry from 2004 through 2019. We included patients aged ≥13 years presenting to the emergency department (ED) with BCVI, defined as a blunt trauma to any of the following vessels: common/internal carotid artery, external carotid artery, vertebral artery, external jugular vein, and internal jugular vein. We delineated characteristics of each BCVI classified according to three damaged vessels (common/internal carotid artery, vertebral artery, and others). In addition, we applied network analysis to unravel patterns of co-occurring injuries among patients with BCVI by four common trauma mechanisms (car accident, motorcycle/bicycle accident, simple fall, and fall from a height). RESULTS: Among 311,692 patients who visited the ED for blunt trauma, 454 (0.1%) patients had BCVI. Patients with common/internal carotid artery injuries presented to the ED with severe symptoms (e.g., the median Glasgow Coma Scale was 7) and had high in-hospital mortality (45%), while patients with vertebral artery injuries presented with relatively stable vital signs. Network analysis showed that head-vertebral-cervical spine injuries were common across four trauma mechanisms (car accident, motorcycle/bicycle accident, simple fall, and fall from a height), with co-occurring injuries of the cervical spine and vertebral artery being the most common injuries due to falls. In addition, common/internal carotid artery injuries were associated with thoracic and abdominal injuries in patients with car accidents. CONCLUSIONS: Based on analyses of a nationwide trauma registry, we found that patients with BCVI had distinct patterns of co-occurring injuries by four trauma mechanisms. Our observations provide an important basis for the initial assessment of blunt trauma and could support the management of BCVI.

Ultrasonography is an effective tool for the evaluation of traumatic vertebral artery injuries distal to fourth cervical vertebra in the emergency room.

BACKGROUND: This study aimed to determine the feasibility of ultrasonography in the assessment of cervical vertebral artery (VA) injury as an alternative to computed tomography angiography (CTA) in the emergency room. METHODS: We analyzed 50 VAs from 25 consecutive patients with cervical spine injury that had been admitted to our emergency room. Ultrasonography and CTA were performed to assess the VA in patients with cervical spine injury. We examined the sensitivity and specificity of ultrasonography compared with CTA. RESULTS: Among these VAs, six were occluded on CTA. The agreement between ultrasonography and CTA was 98% (49/50) with 0.92 Cohen's Kappa index. The sensitivity, specificity, and positive and negative predictive values of ultrasonography were 100%, 97.7%, 85.7%, and 100%, respectively. In one case with hypoplastic VA, the detection of flow in the VA by ultrasonography differed from detection by CTA. Meanwhile, there were two cases in which VAs entered at C5 transverse foramen rather than at C6 level. However, ultrasonography could detect the blood flow in these VAs. CONCLUSIONS: Ultrasonography had a sensitivity of 100% compared with CTA in assessment of the VA. Ultrasonography can be used as an initial screening test for VA injury in the emergency room.

[Dissection technique for organs of the neck in hanging]. / Tekhnika sektsionnogo issledovaniya organokompleksa shei pri poveshenii.

The aim of this study is to develop a comprehensive dissection technique to examine the deep structures of the neck in hanging, including extraction of the cervical spine and investigation of the removed segment with access to vertebral arteries and spinal cord. Its advantages include the unnecessity of any special instruments usage, the short period of time, which is necessary for performing dissection techniques, as well as the possible detailed examination of the spine, spinal cord and vertebral arteries. The improved dissection technique simplifies the diagnosis of injuries and increases the objectivity of the forensic medical examination in hanging.

Safety of early posterior fusion surgery without endovascular embolization for asymptomatic vertebral artery occlusion associated with cervical spine trauma.

PURPOSE: Vertebral artery occlusion (VAO) is an increasingly recognized complication of cervical spine trauma. However, the management strategy of VAO remains heavily debated. Therefore, the aim of this retrospective study was to investigate the safety of early fusion surgery for traumatic VAO. METHODS: This study included a total of 241 patients (average age 64.7 years; 201 men) who underwent early surgical treatment for acute cervical spine injury between 2012 and 2019. The incidence of VAO, cerebral infarction rates, the recanalization rates, and cerebral thromboembolism after recanalization were retrospectively analyzed. RESULTS: VAO occurred in 22 patients (9.1%). Of the 22 patients with VAO, radiographic cerebral infarction was detected in 4 patients (21.1%) at initial evaluation, including 1 symptomatic medullar infarction (4.5%) and 3 asymptomatic cerebrum infarctions. A patient who experienced right medullar infarction showed no progression of the neurologic damage. Follow-up imaging revealed that the VAOs of 9 patients (40.9%) were recanalized, and the recanalization did not correlate with clinical adverse outcomes. The arteries of the remaining 13 (59.1%) patients remained occluded and clinically silent until the final follow-up (mean final follow-up 33.0 months). CONCLUSION: Despite the lack of a concurrent control group with preoperative antiplatelet therapy or endovascular embolization for VAO, our results showed low symptomatic stroke rate (4.5%), high recanalization rate (40.9%), and low mortality rate (0%). Therefore, we believe that the indication for early stabilization surgery as management strategy of asymptomatic VAO might be one of the safe and effective treatment options for prevention of symptomatic cerebral infarction.

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.

Current Outcomes of Blunt Vertebral Artery Injuries.

BACKGROUND: There is no consensus on the treatment of blunt vertebral artery injuries, and studies are limited to small case series. We assessed the natural history and current management of these injuries. METHODS: We performed a retrospective study of a prospectively collected registry at a level I trauma center over a 5-year period. Additional information was gathered from patient charts and imaging review from electronic medical records. We analyzed demographics, mechanism of injury, Glasgow Coma Score, mortality, length of stay, associated injuries, Denver grading scale, neurological findings, level and laterality of injury, delay in diagnosis, treatment, and follow-up imaging. RESULTS: There were 13,080 trauma admissions during this time period yielding 141 patients with blunt vertebral artery injuries from 2013 to 2018 (1.1% incidence). Mean injury severity score (ISS) was 22 with a 30-day mortality of 14 (9.9%). An ISS of greater than 15 is associated with polytrauma and increased mortality. There were 112 (79.4%) associated cervical fractures. C6 and C7 were both equally the most common locations. There was one symptomatic injury manifesting as a cerebellar ischemic infarct. The degree of arterial injury was classified by the Denver grading scale. There were 61 (43.3%) instances of Denver grade I injuries, followed by grade IV at 36 (25.5%), grade II at 34 (24.1%), grade III at 8 (5.7%), and grade V at 1 (0.7%). The level of injury was recorded as follows: V2 = 67 (47.5%), V3 = 56 (39.7%), V1 = 48 (34%), V4 = 14 (9.9%). Medical therapy included aspirin in 93 patients (66%), 31 patients (22%) received systemic anticoagulation with heparin drip, and 2 patients (1%) were administered therapeutic Lovenox. A total of 15 patients (11%) received no medical treatment. There was one intervention in our series. Our only grade V injury was coil embolized. A total of 118 patients (84%) had follow-up imaging. Seventy-eight patients (96%) with grade I and grade II injuries did not worsen, and complete radiographic resolution was found in 50 patients (62%). Grade IV injuries persisted in 22 patients (75.9%). Median time to resolution for grade I and grade II injuries was 7 and 8 days, respectively. Most follow-up scans for grade I and II injuries occurred within 50 days. CONCLUSIONS: Posterior circulation stroke due to blunt vertebral artery injury is rare. In our experience, the natural course of blunt vertebral artery injury was benign and neither delay in medical treatment nor choice of antithrombotic had a significant impact on outcomes. In our series, only 3 (3.7%) grade I and II injuries worsened and were without any clinical sequelae. We suggest that routine serial imaging in grade I and II blunt vertebral injuries is not warranted.

Statistical learning of blunt cerebrovascular injury risk factors using the elastic net.

PURPOSE: To compare logistic regression to elastic net for identifying and ranking clinical risk factors for blunt cerebrovascular injury (BCVI). MATERIALS AND METHODS: Consecutive trauma patients undergoing screening CTA at a level 1 trauma center over a 2-year period. Each internal carotid artery (ICA) and vertebral artery (VA) was independently graded by 2 neuroradiologists using the Denver grading scale. Unadjusted odds ratios were calculated by univariate and adjusted odds ratios by multiple logistic regression with FDR correction. We applied logistic regression with the elastic net penalty and tenfold cross-validation. RESULTS: Total of 467 patients; 73 patients with BCVI. Maxillofacial fracture, basilar skull fracture, and GCS had significant unadjusted odds ratios (OR) for ICA injury and C-spine fracture, spinal ligamentous injury, and age for VA injury. Only transverse foramen fracture had significant adjusted OR for VA injury, with none for ICA injury, after FDR correction. Using elastic net, ICA injury variables included maxillofacial fracture, basilar skull fracture, GCS, and carotid canal fracture. For VA injury, these included cervical spine transverse foramen fracture, ligamentous injury, C1-C3 fractures, posterior element fracture, and vertebral body fracture. CONCLUSION: Elastic net statistical learning methods identified additional risk factors and outperformed multiple logistic regression for BCVI. Elastic net allows the study of a large number of variables, and is useful when covariates are correlated.

Morphological characteristics of the posterior neck muscles and anatomical landmarks for botulinum toxin injections.

PURPOSE: Cervical dystonia is a common movement disorder for which botulinum toxin (BoNT) is the first choice treatment. Injecting the specific neck muscles can be challenging because of their thin morphology and deep locations. We, therefore, designed a study to investigate the locations of the posterior neck muscles to help the physician predict the locations of the targeted neck muscles and to protect the vertebral vessels from injury during deep injections. METHODS: The posterior neck region was divided into four quadrants by imaginary lines passing vertically and transversely through the spinous process of C2 vertebra (C2sp). The thicknesses and depth of the posterior neck muscles were measured in ten formaldehyde-fixed adult male cadavers. These muscles were located and a projection of them was drawn on the neck. Using the measurements, colored latex in place of BoNT was injected into them in one cadaver. The cadaver was dissected to investigate whether the muscles were colored. RESULTS: 2 cm above the C2sp, trapezius, splenius capitis (SPC) and semispinalis capitis (SSC) were colored at depths of 10.70 mm, 11.88 mm and 15.91 mm, respectively. 2 cm below the C2sp, the trapezius, SPC and SSC were colored at depths of 20.89 mm, 23.25 mm and 27.63 mm, respectively. The posterior neck muscles were had taken up their assigned colors when they were injected according to the results obtained in this study. The vertebral vessels were not colored. CONCLUSIONS: Although BoNT injection into the posterior neck muscles is challenging, we think that it can be practically and safely applied using the measurements obtained in this study.

Dual origin of vertebral artery and intimal relationship with spontaneous artery dissection: a case report and systematic review.

Dual origin of the vertebral artery (VA) is an uncommon anatomical variation. We describe a case of duplication origin at right vertebral artery (RVA) found incidentally in one elderly patient on investigation for cerebral aneurysm. Angiogram study showed a pseudoaneurysm at V4 segment of the RVA associated with embryological anatomy. The authors performed a systematic review of the similar cases reported worldwide.

An anatomical investigation of the proximal vertebral arteries (V1, V2) in a select South African population.

INTRODUCTION: The most common type of vascular complication during cervical spine surgery is the vertebral artery (VA) injury. The presence of anatomical variation in the artery's morphology has been a significant factor for arterial injury during surgery. Therefore, physicians planning interventions in the craniospinal region need to be aware of the extents of variations. In addition to vascular injury, anatomical variations can predispose to some pathologies in the posterior circulation territory. To provide useful data to interventional radiologists, anatomists, and surgeons, we evaluated the anatomical features of the V1 and V2 segments of the VA in a South African population. MATERIALS AND METHODS: The study is an observational, retrospective chart review of 554 consecutive South African patients (Black, Indian and White) who had undergone computed tomography angiography (CTA) from January 2009 to September 2019. RESULTS: The VA exhibited morphological variation in its course. We report the incidence of variant origin of the left VA, all from the aortic arch. Variation in the level of entry into the transverse foramen ranged between C7 and C3. A left dominant pattern was observed; we also report on hypoplasia of the VA. In addition, we report incidence of VA tortuosity at V1, V2 to be 76.6% and 32.1%, respectively. CONCLUSIONS: The baseline data established in this study regarding the diameter, variant origin, and level of entry into the transverse foramen will assist neurosurgeons and interventional radiologists in interpreting, diagnosing, and planning and executing various vascular procedures and treatment of pathology in the vicinity of the VA.

Characteristics and Forensic Identification of Blunt Vertebral Artery Injury.

ABSTRACT: Blunt vertebral artery injury occurs frequently in forensic practice. However, injuries of the vertebral artery are easily ignored or overlooked because of its relatively deep location. Through literatures review, this paper finds that the manners of blunt vertebral artery injury are varied and one or more injury mechanisms may be involved simultaneously. Patients often undergo immediate or delayed cerebral apoplexy as well as compression and injury of surrounding structures, due to direct injury or secondary aneurysm or dissection, resulting in disability or death. Diseases such as, vertebral atherosclerosis and dysplasia can increase the disability and death risk and the difficulty of forensic identification. In forensic identification, the details of the case should be considered. For cases of suspected vertebral artery injury, in addition to routine examination of intracranial segment, attention should be paid to the examination of extracranial segment. If conditions permit, angiography can be used prior to or during the autopsy to improve the identification efficiency and accuracy of opinions.

A systematic review of penetrating extracranial vertebral artery injuries.

BACKGROUND: Penetrating vertebral artery injuries (VAIs) are rare. Because of their rarity, complex anatomy, and difficult surgical exposures, few surgeons and trauma centers have developed significant experience with their management. The objectives of this study were to review their incidence, clinical presentation, radiologic identification, management, complications, and outcomes and to provide a review of anatomic exposures and surgical techniques for their management. METHODS: A literature search on MEDLINE Complete-PubMed, Cochrane, Ovid, and Embase for the period of 1893 to 2018 was conducted. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used. Our literature search yielded a total of 181 potentially eligible articles with 71 confirmed articles, consisting of 21 penetrating neck injury series, 13 VAI-specific series, and 37 case reports. Operative procedures and outcomes were recorded along with methods of angiographic imaging and operative management. All articles were reviewed by at least two independent authors, and data were analyzed collectively. RESULTS: There were a total of 462 patients with penetrating VAIs. The incidence of VAI in the civilian population was 3.1% vs 0.3% in the military population. More complete data were available from 13 collected VAI-specific series and 37 case reports for a total of 362 patients. Mechanism of injury data were available for 341 patients (94.2%). There were gunshot wounds (178 patients [49.2%]), stab wounds (131 [73.6%]), and miscellaneous mechanisms of injury (32 [8.8%]). Anatomic site of injury data were available for 177 (49%) patients: 92 (25.4%) left, 84 (23.2%) right, and 1 (0.3%) bilateral. Anatomic segment of injury data were available for 204 patients (56.4%): 28 (7.7%) V1, 125 (34.5%) V2, and 51 (14.1%) V3. Treatment data were available for 212 patients. Computed tomography angiography was the most common imaging modality (163 patients [77%]). Injuries were addressed by operative management (94 [44.3%]), angiography and angioembolization (72 [34%]), combined approaches (11 [5.2%]), and observation (58 [27.4%]). Stenting and repair were less frequently employed (10 [4.7%]). The incidence of aneurysms or pseudoaneurysms was 18.5% (67); the incidence of arteriovenous fistula was 16.9% (61). The calculated mortality in VAI-specific series was 15.1%; in the individual case report group, it was 10.5%. CONCLUSIONS: The majority of VAIs present without neurologic symptoms, although some may present with exsanguinating hemorrhage. Computed tomography angiography should be considered first line to establish diagnosis. Gunshot wounds account for most injuries. The most frequently injured segment is V2. Surgical ligation is the most common intervention, followed by angioembolization, both of which constitute important management approaches.

Anatomical investigation of the segmental vessels for the right-sided anterior surgical approach to the thoracic spine: a human cadaver study.

PURPOSE: Anterior surgical approaches to the thoracic spine are common procedures for the treatment of many diseases of the thoracic spine. Purpose of this anatomic study is to investigate the course of the segmental vessels of the thoracic spine for the anterior and lateral transthoracic approach from the right side. METHODS: 26 formalin-fixed human cadavers (20 femaless/6 male) with an average age of 84.9 ± 8.3 (range 67-97) were included. The segmental arteries and veins of the right thoracic cavity coursing between the third and twelfth thoracic vertebral body have been investigated. To define the localization of the vessels in accordance with the associated vertebral bodies, the distance between the endplates and vessels was measured in the ventral, middle and dorsal parts. RESULTS: The results of the study reveal that not only one, but also two segmental arteries and veins may course over the right hemi-vertebral body, especially in the upper and middle thoracic spine. Furthermore, in the middle and lower thoracic spine (T7-T12) the vessels course over the middle and lower third of the craniocaudal extent of the vertebral body. On the contrary, in the upper thoracic spine (T3-T6), the vessels may course over the entire extent of the vertebral body. CONCLUSION: Due to these common anatomic variations and variability of the course of the segmental vessels, spinal surgeons should remain careful in the identification of the segmental vessels in order to minimize risk of vascular injury in case of right-sided anterior and lateral approach to the thoracic spine.

Follow-up imaging of traumatic vertebral artery dissections is unnecessary in asymptomatic patients.

OBJECTIVE: Routine computed tomography (CT) imaging in trauma patients has led to increased recognition of blunt vertebral artery injuries (BVIs). We sought to determine the prevalence of strokes, injury progression, and need for intervention in patients with BVI. METHODS: Consecutive patients presenting with BVI during 2 years were identified from the institutional trauma registry. Inpatient records, imaging studies, and follow-up data were reviewed in detail from the electronic medical record. RESULTS: There were 76 BVIs identified in 70 patients (64% male; mean age, 47 ± 19 years); bilateral injuries occurred in 6 patients. Five patients who arrived at the hospital intubated had evidence of posterior circulation infarcts on admission CT, whereas one additional patient had evidence of a posterior circulation infarct attributed to complications of late spinal surgery. Four of the five patients with infarcts on admission CT survived to discharge, but only one had residual stroke symptoms. Minor (grade 1 or grade 2) injuries occurred in 25 (36%) patients; severe (grade 3 or grade 4) injuries occurred in 45 (64%). Twelve patients died of associated injuries (eight with severe BVI, four with minor BVI). Stepwise logistic regression analysis selected age (odds ratio, 1.14; confidence interval, 1.04-1.25; P < .001) and intubation on arrival (odds ratio, 450.4; confidence interval, 17.41-1645.51; P < .001) as independent predictors of hospital stroke and death. Of the 58 surviving to discharge, 31 (53%) returned for follow-up CT scans. Six of 10 (60%) patients with minor injuries had resolution or improvement compared with 3 of 21 (14%) with severe injuries (P = .027). One patient (10%) with a minor BVI and two patients (10%) with severe BVI had radiologic progression, but none were clinically significant. During a mean follow-up of 15 ± 13 months, none of the study patients had treatment (surgical or interventional) for BVI, and there were no delayed strokes. Only five patients in this series had vertebral pseudoaneurysms, which limits conclusions about this type of BVI. CONCLUSIONS: These data suggest that BVI-related strokes are present at the time of admission and do not have clinical sequelae. No late strokes occurred in this series, and no surgical or interventional treatments were required even in the presence of radiographic worsening. The relatively few cases of vertebral pseudoaneurysms in this series limit any conclusions about these specific lesions. However, these data indicate that follow-up imaging of nonaneurysmal BVI is not necessary in adults who are found to be asymptomatic on follow-up.

Risk assessment of vertebral artery injury in anterior controllable antedisplacement and fusion (ACAF) surgery: a cadaveric and radiologic study.

PURPOSE: We have introduced a novel surgery technique named anterior controllable antedisplacement and fusion (ACAF) for the treatment of ossification of the posterior longitudinal ligament. As reported, the satisfactory postoperative outcome can be attributed to the larger decompression width. However, it may associate with high prevalence of vertebral artery injury (VAI) theoretically. Thus, assessment of the vulnerability of vertebral artery in ACAF is of great importance. METHODS: Computed tomographic scan data of 28 patients were retrospectively studied. Seven radiographic parameters were evaluated: uncinate process (UP) tips distance, transverse foramen (TF)-UP tips distance, TF-LWL (the ipsilateral limited wedging line) distance, the limited distance of lateral decompression, the maximum oblique angle of LWL, TF-LWG (the lateral wall of groove) distance, and width of groove. Eleven fresh cadaveric spines undergoing ACAF surgery were also studied. Two anatomic parameters were evaluated: width of groove and LWG-TF distance. RESULTS: The UP tips distance increased from C3 to C6 and tended to be larger in males. The UP tip-TF distance and LWL-TF distance were smallest at C4, but both were larger than 2 mm. Maximum oblique angle decreased from C3 to C6. Postoperatively, both radiographic and cadaveric measurements showed the width of groove was larger than UP tips distance, but LWG-TF distance was larger than 2 mm in all levels. CONCLUSION: UP can be used as anatomical landmarks to avoid VAI during ACAF surgery. Radiographic and cadaveric measurements verified the safety of ACAF surgery, even for those cases with wedging and lateral slotting.