Carotid and vertebral artery trauma: clinical and angiographic features

Atraumatic Vertebral Dissection in a Patient With Altered Mental Status

The most common manifestations of vertebral artery dissection in approximately 80% of patients are headaches or neck pain. We discuss a case of a 34-year-old patient who presented to the emergency department with altered mental status and nonspecific symptoms. A CT angiogram with intravenous contrast revealed a dissection of the left vertebral artery, and the patient was found to have thromboembolism in the right occipital lobe with ischemia on MRI. This case demonstrates the importance of maintaining a broad differential diagnosis for patients who present with altered mental status and nonspecific symptoms such as headache and neck pain in order to adequately diagnose a potentially fatal condition.

Bilateral Carotid and Vertebral Artery Dissection from Blunt Trauma

Carotid and vertebral artery injuries are rare following blunt trauma. They can, however, lead to severe consequences with a significant associated rate of stroke and intracranial hemorrhage, particularly if the diagnosis and treatment are delayed. We report a case of a 23-year-old female who presented to the Emergency Department with bilateral carotid and vertebral artery dissection following a motor vehicle collision (MVC).

Vertebral artery injury after blunt cervical trauma: an update

BACKGROUND

Vertebral artery injury (VAI) after blunt cervical trauma has been considered to be rare. The incidence of VAI has increased dramatically within the last decade after a heightened awareness of this entity on the part of spine surgeons. Diagnostic or therapeutic guidelines for VAI have not been established fully, however.

METHODS

A review of the literature published between 1990 and 2004 was conducted.

RESULTS

The incidence of VAI among total blunt trauma admissions ranged from 0.20% to 0.77%. Most VAI patients remained asymptomatic, but sudden unexpected deterioration was often reported. Distraction/extension, distraction/flexion, and lateral flexion injuries were the major mechanisms of injury. Dissection and occlusion were the frequent vascular injury patterns. Facet joint dislocations and the fractures extending into the transverse foramen were the spine injury patterns closely associated with VAI. Digital subtraction angiography was the most sensitive imaging study, but because of invasiveness, its role as a screening study remained questionable. Neuroradiological intervention was used successfully to treat hemorrhagic VAI and progressing vertebrobasilar stroke. Systemic anticoagulation with heparin was the preferred treatment for mild ischemia. Treatment of asymptomatic patients has been controversial because the natural history of VAI has not been elucidated. Prophylactic anticoagulation with heparin or the use of antiplatelet agents was advocated in recent studies.

CONCLUSIONS

Preemptive treatment may be reasonable in selected patients considering the devastating potentials of VAI. The potential risks of heparin or antiplatelet agents in relation to early cervical spine surgery have not been addressed fully, however, and spine surgeons have to weigh the risk and benefit of such treatment cautiously.

Imaging of Traumatic Neurovascular Injury

Traumatic injury to the major vessels of the head and neck can result in potentially devastating neurologic sequelae. Until recently, conventional angiography was the primary imaging modality used to evaluate these often challenging patients. Advances in cross-sectional imaging have improved the ability to screen for these lesions, which have been found to be more common than previously thought; however, accepted protocols of imaging evaluation have not yet been fully established. This article presents a general approach to the patient with suspected neurovascular injury. This includes a discussion of the histopathologic spectrum, clinical presentation, mechanisms, radiologic work-up, pertinent issues of the most common lesions, and some of the endovascular techniques used in their management.

Noninvasive imaging of cervical vascular injuries

Various imaging examinations can be used to diagnose cervical vascular injuries. The challenge in the current medical environment is to choose the imaging examination that is the most rapid, least invasive, and least costly. One must recognize the ability of each technique to detect lesions, taking into consideration the type of abnormality and whether the carotid or vertebral arteries are at risk for injury.

Blunt cerebrovascular injuries

On the basis of our experience and the available literature, we submit that aggressive screening for BCI based on injury patterns is warranted. However, several important clinical issues remain unresolved. The precise injury patterns and relative cerebrovascular risks remain to be defined. Furthermore, the optimal diagnostic screening test remains to be identified, with consideration of the relative risk-benefit profile. Finally, we must determine the best methods for the treatment of BCI. Although the definitive study has yet to be completed, the use of heparin was associated with a trend toward improved outcomes in symptomatic patients. In addition, no asymptomatic patient experienced the development of new neurologic deficits during heparin therapy. Therefore we believe that the early institution of heparin therapy is indicated. The role of endovascular stenting, however, remains unclear.

Helical CT of cervical spine and soft tissue injuries of the neck

Helical CT of the neck has revolutionized the diagnostic evaluation of trauma and emergency room patients. This comprehensive examination, with high resolution and fast acquisition times, allows the radiologist to make expeditious diagnoses concerning cervical spine fractures, vascular injuries, and aero-digestive tract lesions. This allows for the more rapid triaging and treatment of various injuries resulting in improved patient priate radiographic examination for each clinical scenario.

Risk factors and precipitating neck movements causing vertebrobasilar artery dissection after cervical trauma and spinal manipulation

STUDY DESIGN

Potential precipitating events and risk factors for vertebrobasilar artery dissection were reviewed in an analysis of the English language literature published before 1993.

OBJECTIVES

To assess the literature pertaining to precipitating neck movements and risk factors for vertebrobasilar artery dissection in an attempt to determine whether the incidence of these complications can be minimized.

SUMMARY OF BACKGROUND DATA

Vertebrobasilar artery dissection and occlusion leading to brain stem and cerebellar ischemia and infarction are rare but often devastating complications of cervical, manipulation and neck trauma. Although various investigators have suggested potential risk factors and precipitating events, the basis for these suggestions remains unclear.

METHODS

A detailed search of the literature using three computerized bibliographic databases was performed to identify English language articles from 1966 to 1993. Literature before 1966 was identified through a hand search of Index Medicus. References of articles obtained by database search were reviewed to identify additional relevant articles. Data presented in all articles meeting the inclusion criteria were summarized.

RESULTS

The 367 case reports included in this study describe 160 cases of spontaneous onset, 115 cases of onset after spinal manipulation, 58 cases associated with trivial trauma, and 37 cases caused by major trauma (3 cases were classified in two categories). The nature of the precipitating trauma, neck movement, or type of manipulation that was performed was poorly defined in the literature, and it was not possible to identify a specific neck movement or trauma that would be considered the offending activity in the majority of cases. There were 208 (57%) men and 158 (43%) women (gender data not reported in one case) with an average age of 39.3 +/- 12.9 years. There was an overall prevalence of 13.4% hypertension, 6.5% migraines, 18% use of oral contraception (percent of female patients), and 4.9% smoking. In only isolated cases was specific vascular disease such as fibromuscular hyperplasia noted.

CONCLUSIONS

The literature does not assist in the identification of the offending mechanical trauma, neck movement, or type of manipulation precipitating vertebrobasilar artery dissection or the identification of the patient at risk. Thus, given the current status of the literature, it is impossible to advise patients or physicians about how to avoid vertebrobasilar artery dissection when considering cervical manipulation or about specific sports or exercises that result in neck movement or trauma.

Clinical assessment of posttraumatic headaches

The evaluation of the person with posttraumatic headache remains a difficult clinical task. The rehabilitation clinician seeing the person with posttraumatic headache may encounter a large spectrum of potential etiologies for cephalgia. We believe an ordered approach to the history, physical, and laboratory examination may lead to a more accurate and focused diagnosis in some cases. In an attempt to provide a directed approach to posttraumatic headaches, this discussion is divided into extracranial and intracranial sources. A brief table guide to the etiology of pain by site is presented, and the key eight steps of examination are reviewed.

Traumatic carotid artery dissection

Traumatic carotid artery dissection is rarely seen as a cause of death in the forensic setting. Three cases of traumatic carotid artery dissection that demonstrate many of the typical features are presented. There is usually a history of some violent trauma to the head or neck, motor vehicle accidents being the commonest cause. The carotid artery may be injured anywhere from the common carotid portion to the cavernous sinus, resulting in infarction of the corresponding cerebral hemisphere. Clinically, symptoms may include loss of consciousness, hemiparesis, aphasia, and Horner's syndrome, these typically occurring after an interval of hours to days. Carotid artery injury may not be associated with evidence of external injury and initially may go undetected or may be misinterpreted in the setting of associated neck or head trauma. The commonest mechanisms are thought to be blunt neck trauma and neck hyperextension. The cases presented highlight the importance of early diagnosis if surgery is to be possible to avoid a fatal outcome.

Magnetic resonance angiographic analysis of atlanto-axial rotation: anatomic bases of compression of the vertebral arteries

The aim of this study was to identify the functional anatomic factors involved in the maintenance or disturbance of flow in the vertebral aa. during atlanto-axial rotation. Fourteen healthy volunteers were studied by magnetic resonance angiography (MRA) by a three-dimensional sequence in phase contrast centered on the vertebral aa. at the level of the cranio-cervical junction before and after left rotation of the head. A decrease in the signal intensity of the arterial flow was sought for. The results were compared to the posterolateral development of the loop of the vertebral a. in its atlanto-axial segment in neutral position, and to the measurement of the angular opening between the atlas and axis in dynamic position. Seven subjects also had a three-dimensional CT study (3D CT) of the bony relations of C1 and C2 after rotation. In 4 subjects a disturbance of flow in the right vertebral a. was observed in the transverse foramen of C2. This occurred when two factors were combined: an under-developed atlanto-axial arterial loop and a C1-C2 angle exceeding 35 degrees in maximal rotation. In the other subjects a well-developed arterial loop and/or a C1-C2 angle of less than 35 degrees in maximal rotation were factors preserving the arterial flow. The risk factor associated with the C1-C2 angle seemed correlated in 3D CT with loss of the usual asymmetric character of rotation. A clinical application is reported with a case combining chronic rotational dysfunction of the cranio-cervical junction as shown by 3D CT and complete compression of the vertebral a. in MRA, confirmed by conventional angiography. A knowledge of this physiopathologic mechanism allows clinical detection and evaluation of the risk of any effect of pathology of the cranio-cervical junction on the vertebral a.

Carotid and vertebral artery occlusion after blunt cervical injury: the role of MR angiography in early diagnosis

The early diagnosis of cervical vascular trauma is critical in the prevention of cerebral ischemia. Traumatic blunt carotid or vertebral artery dissection is rare and frequently associated with other injuries. Diagnosis is often delayed, limiting treatment options and contributing to a poor outcome. The clinical findings and investigation of 14 patients are presented with special reference to the last three who had magnetic resonance imaging angiography. Treatment options are discussed and it is suggested that with modern methods of investigation and management, the prognosis of this condition may be improved.

Vertebral artery dissection due to minor neck trauma

Vertebral artery dissection has been previously reported following minor head and neck trauma. Such activities as rapid head turning, tennis, yoga, and vigorous exercise have been implicated. We report a case of vertebral artery dissection following minor neck trauma suffered in a volleyball game. The anatomy of the vertebral artery, pathophysiology of dissection, and emergency department recognition and treatment of this disorder are discussed.