The relation between the spatial distribution of vertebral artery compromise and exposure to cervical manipulation

Background and purpose The vertebral artery is made up of four segments, one of which (V3) is connected to highly mobile cervical vertebrae. This connection underlies the common assumption that persons with pre-event histories of mechanical neck movements, such as cervical spine manipulation (cSMT), should experience increased V3 dissection. Methods Two of the largest case series of vertebral artery dissection describing subjects with and without a specific history of cSMT were reassessed to determine which segment(s) of the vertebral artery was most commonly compromised. Results The V3 segment was the most commonly involved vertebral artery segment in both the +cSMT group (e.g., V3 vs. V1 prevalence ratio (PR) = 8.46) and the –cSMT group (V3 vs. V1 PR = 4.00). However, V3 vulnerability was augmented by the effect of cSMT. The joint effect of V3 location and exposure to cSMT was greater than if each effect were simply combined. In addition,multiple site lesions were significantly more common than single sites in both the +cSMT group (PR = 2.67, p = 0.008) and the –cSMT group (PR = 2.44, p = 0.0008). Conclusions In prior studies which identified vertebral artery compromise, those with a history of cSMT were more likely to have involvement of the V3 segment. Although this study does not identify a mechanism which relates vertebral artery dissection and exposure to cSMT, these data are compatible with a greater than additive relation between compromise of an arterial segment thought to be mechanically vulnerable and history of a mechanical event.     

寰枢段椎动脉在远外侧入路中的应用显微解剖研究

目的 为颅颈交界区手术入路提供解剖学参数,帮助神经外科医生安全、准确地暴露手术靶区.方法 应用10％甲醛固定的汉族成人尸头标本10例20侧;漂白干颅骨及寰枢椎10例20侧.模拟手术入路逐层解剖,并对解剖结构进行精确测量和拍照.结果 寰枢段椎动脉在颅颈交界区形成比较恒定的五个生理弯曲,平均直径(4.3±0.5) mm,角度多变.寰椎后弓外侧半距(19.3±4.7)mm.结论 熟悉寰枢段椎动脉五个生理弯曲的定位方法,有助于提高颅颈交界区手术入路的安全性.     

Rotational vertebral artery syndrome due to compression of nondominant vertebral artery terminating in posterior inferior cerebellar artery

Rotational vertebral artery syndrome (RVAS) is characterized by recurrent attacks of paroxysmal vertigo, nystagmus, and ataxia induced by head rotation. We report on a patient who developed atypical RVAS due to compression of the vertebral artery (VA) terminating in the posterior inferior cerebellar artery (PICA). A 59-year-old man suffered from vertigo and nystagmus induced by leftward head rotation and oculography showed right beating horizontal-torsional and downbeat nystagmus. Cerebral angiography showed hypoplastic right VA terminating in PICA without connection to the basilar artery. The basilar artery received its flow from the left VA only and branched out both anterior inferior cerebellar arteries. Cerebral angiography revealed a complete occlusion of the right distal VA at the level of the C1–2 junction when the head was rotated to a leftward position. In contrast, the blood flow through the left vertebral and basilar arteries remained intact while turning the head to either side. The hemodynamic compromise observed in our patient with RVAS indicates that isolated vertigo and nystagmus may occur due to transient ischemia of the inferior cerebellum or lateral medulla.     

Labyrinthine infarction caused by vertebral artery dissection: consideration based on MRI

Journal of Neurology -     

Congestion of epidural venous plexus secondary to vertebral artery occlusion mimicking a herniated cervical disc

Vascular abnormalities or dissection of the vertebral artery are rare causes for cervical monoradiculopathy. We present the case of a 44-year-old female patient with a short history of radiculopathy of the right C5 root with radicular pain and a severe motor deficit. CT-imaging showed a hyperdense structure at the C4/C5 level suggesting a herniated disc. Because of the neurological deficit the patient was operated by a dorsal approach. Intraoperatively no herniated disc but only a congested epidural venous plexus was found. Postoperative MRI and angiography showed occlusion of the vertebral artery from C3 to C6 level probably due to dissection. The present case shows that a CT-study suggestive for a herniated disc can be misleading. Enlargement of the vertebral artery secondary to dissection or occlusion may lead to compression of the venous plexus which resembles disc material on CT-scan.     

颈性眩晕患者椎动脉磁共振血管成像的变化

目的 探讨颈性眩晕患者椎动脉磁共振血管成像(MRA)的变化及其临床意义.方法 应用MRA对78例颈性眩晕患者和45例后循环缺血(PCI)患者椎动脉进行检查,并对结果进行比较.结果 颈性眩晕组患者椎动脉迂曲率(65.4%)显著高于PCI组(48.9%)(P＜0.01);椎-基底动脉狭窄率(3.8%)显著低于PCI组(66.7%)(P＜0.01);椎动脉发育不良率两组相比差异无统计学意义.结论 椎动脉迂曲可能与颈性眩晕发病有关;椎动脉MRA检查有助于颈性眩晕的诊断.     

Dissecting aneurysm of the vertebral artery and cervical manipulation: a case report with autopsy

A 35-year-old woman with 3 weeks of cervical pain developed ischemia in the basilar artery territory following cervical manipulation. At autopsy, there was a dissecting aneurysm within the third segment of the right vertebral artery. The pathologic changes in the lower and the upper part of the dissecting aneurysm were different, indicating recurring bleeding. Cervical manipulation could have accounted for one recent dissection, but not for another, which was a few weeks old. This suggests that cervical pain, which prompted the manipulation, may have been the first symptom of the dissection, and manipulation of the neck precipitated the stroke by inducing bleeding within the dissecting aneurysm.     

A case of spontaneous cervical vertebral artery dissection resulting in Wallenberg's syndrome--diagnostic value of the cervical axial MRI

Findings of the cervical axial MRI are discussed in a case of spontaneous cervical vertebral artery dissection resulting in Wallenberg's syndrome. A 42-year-old male was hospitalized because of sudden onset of severe occipital pain. Cerebral angiography performed on the day of admission revealed severe tapering stenosis of the right vertebral artery at the C-5 level of the vertebra. Angiography repeated 50 days later showed partial resolution of the narrowing. T-1 weighted axial MRI of the neck demonstrated significantly narrowing flow void of the right vertebral artery when compared with the contralateral side. A crescent-like high intensity area was also seen surrounding the lumen. These findings were consistent with hematoma within the dissected wall of the vertebral artery. MRI is considered useful in identifying such vascular lesions as cerebral artery dissection.     

Giant cell tumour of the sixth cervical vertebrae with close relationship to the vertebral artery.

Giant cell tumours of the vertebral column are rare and cervical vertebrae involvement is even less common. As these lesions may be closely related to the vertebral artery, therapeutic decision-making may be complex. Reviewing the literature, we found that there was no consensus on treatment or outcome assessment for these rare and difficult lesions. We present a case of a giant cell tumour of the sixth cervical vertebrae involving the posterior elements, neural foramina and transverse foramina and closely related to the vertebral artery. Radiological evaluation and therapeutic solutions are also discussed.     

Traumatic pseudoaneurysms of the superficial temporal artery: Case series,anatomy, and multidisciplinary treatment considerations

Pseudoaneurysms of the superficial temporal artery (STA) are rare vascular lesions of the external carotid artery system and are most often incurred after blunt head trauma. Diagnosis can be made on clinical grounds, and is confirmed by ultrasonography (US) or CT angiography. Surgical ligation and excision of the aneurysm remains a definitive treatment modality. Patients with STA pseudoaneurysms are often referred to a neurovascular specialist given the neurovascular origin and gross anatomic location of these lesions. Three patients presented to our neurovascular service several weeks following blunt head injury to the anterolateral skull surface with progressive, palpable, pulsatile masses. Each patient underwent CT angiography, which demonstrated a pseudoaneurysm of the frontal branch of the STA, followed by operative ligation and en bloc excision. The present series highlights the anatomical considerations relevant to STA injury and pseudoaneurysm formation following blunt head trauma and reviews the necessary diagnostic and treatment considerations.     

Surgical management of primary tumors of the cervical spine: surgical considerations and avoidance of complications

Abstract

Objective:

Primary cervical spinal tumors are rare tumors of the spine and are associated with significant morbidity and mortality. Such tumors include multiple myeloma, chordomas, giant cell tumors, hemangiomas, osteosarcomas, chondrosarcomas, synovial sarcomas, aneurysmal bone cysts (ABC), hemangiomas, eosinophilic granulomas, osteoid osteomas, and osteoblastomas. We review the surgical decision-making process and identify critical key steps for surgical complication avoidance. We also present case illustrations demonstrating such pathological diagnoses and surgical treatments performed.

Methods:

We retrospectively review the literature regarding the most common primary cervical spinal tumors that have undergone surgical resection with or without adjuvant treatment.

Results:

En bloc resection of primary cervical tumors resulted in significantly increased progression-free survival and overall survival. From the limited data, adjuvant treatment with proton-beam therapy for chordomas has potential benefit. Neo-adjuvant chemotherapy for Ewing’s sarcoma and osteogenic sarcoma has shown some promise, with en bloc resection demonstrating stronger benefit for osteogenic sarcoma.

Discussion:

En bloc resection for primary spinal tumors has proven to be the standard of care in spinal oncology. Adjuvant and neo-adjuvant treatments such as chemotherapy and radiotherapy variants (conventional, proton beam, cyberknife) need to be studied further in most primary tumor types to become standard of care. Chordoma management is more widely studied with en bloc resection and adjuvant proton-beam therapy demonstrating improved progression-free survival and overall survival. Surgical management and adjuvant treatment strategies are case dependent, depending on tumor histology, patient neurological examination, prior surgeries at that level, and prior adjuvant treatment.     

Quantitative assessment of forelimb motor function after cervical spinal cord injury in rats: relationship to the corticospinal tract

Approximately 50% of human spinal cord injuries (SCI) are at the cervical level, resulting in impairments in motor function of the upper extremity. Even modest recovery of upper extremity function could have an enormous impact on quality of life for quadriplegics. Thus, there is a critical need to develop experimental models for cervical SCI and techniques to assess deficits and recovery of forelimb motor function. Here, we analyze forelimb and forepaw motor function in rats after a lateral hemisection at C5 and assessed the relationship between the functional impairments and the extent of damage to one descending motor system, the corticospinal tract (CST). Female Sprague-Dawley rats were trained on various behavioral tasks that require the forelimb, including a task that measures gripping ability by the hand (as measured by a grip strength meter, GSM), a food reaching task, and horizontal rope walking. After 8 weeks of post-injury testing, the distribution of the CST was evaluated by injecting BDA into the sensorimotor cortex either ipsi- or contralateral to the cervical lesion. Complete unilateral hemisection injuries eliminated the ability to grip and caused severe impairments in food retrieval by the forepaw ipsilateral to the lesion. There was no indication of recovery in either task. In cases in which hemisections spared white matter near the midline, there was some recovery of forelimb motor function over time. Assessment of rope climbing ability revealed permanent impairments in forelimb use and deficits in hindlimb use and trunk stability. Sensory testing using a dynamic plantar aesthesiometer revealed that there was no increase in touch sensitivity in the affected forelimb. For the cases in which both histological and behavioral data were available, spared forelimb motor function was greatest in rats in which there was sparing of the dorsal CST.     

The V2 segment of the vertebral artery in anterior and anterolateral cervical spinal surgery: a cadaver angiographic study

OBJECTIVE: The second segment of the vertebral artery is under the risk of injury during anterior and anterolateral cervical spine procedures. To avoid such a risk, one needs to be familiar with the regional anatomy. The aim of this study was to measure the distance between the vertebral artery and the uncinate process, midline, and the medial side of the longus colli muscle using vertebral artery angiograms at the level of C6, C5, C4, and C3 vertebrae. MATERIALS AND METHODS: In 12 human cadavers, the vertebral arteries were first irrigated with water. Then the arteries were filled with silicon and barium, and finally their angiographic images were obtained. RESULTS: The transverse diameter of the vertebral artery was measured at C6, C5, C4, C3, and C2 level. The values on the left were bigger than the values on the right (p>0.05). The distance between the vertebral artery and the midline decreased from C6 (17.2+/-5.6mm on the right, 17.2+/-2.3mm on the left) to C3 (15.8+/-5.3mm on the right, 13.8+/-2.1mm on the left) (p>0.05). The distance between the apex of the uncinate process and the medial side of the vertebral artery was found to be longer at C4 (2.7+/-1.0 mm on the right, 2.2+/-1.0mm on the left) and C5 (2.5+/-1.1mm on the right, 2.5+/-1.0mm on the left) vertebra levels on the right side (p=0.339 at C4, p=0.862 at C5). The distance between the medial side of the longus colli muscle and the medial side of the vertebral artery was measured as 9.7+/-2.7 mm (9.5+/-2.9 mm on the right, 9.8+/-2.6mm on the left) at C6 level, 9.2+/-2.6mm (8.6+/-2.4mm on the right, 9.8+/-3.1mm on the left) at C5, 9.4+/-1.9 mm (9.2+/-2.1mm on the right, 9.5+/-2.0mm on the left) at C4, and 10.4+/-2.7 mm (10.5+/-3.0mm on the right, 10.1+/-2.6mm on the left) at C3 vertebra level. No significant difference was found between the right and the left (p>0.05). The angle between the vertebral artery and the midline was measured as 4.0+/-1.9 degrees on the right and 2.2+/-1.4 degrees on the left side (p=0.030). CONCLUSION: It was considered that the values obtained could be useful in anterolateral and anterior cervical approaches in terms of evaluating the position of the vertebral artery and its relation to vertebral structures. It is also concluded that the risk of injury in upper subaxial cervical spine is higher than in the lower part of the subaxial cervical spine.