Hypoplasia Of Left Vertebral Artery Research Articles

Multidetector computed tomography evaluation of origin, V2 segment variations and morphology of vertebral artery.

The current study aimed to determine the origin of vertebral artery (VA) on both sides and the levels of entry into respective foramen transversarium (FT), to evaluate possible effects of sex on the entry levels, and to investigate the frequency of VA dominance and VA hypoplasia based on the VA V2 segment. For this study, archived images of patients undergoing multidetector computed tomography (MDCT) examination of the chest and headneck for various reasons at Gaziantep University Medical Faculty Hospital were reviewed retrospectively. Three-dimensional reconstructions were performed for a total of 644 VA images from 322 patients using Horos software, and VA origin, the level of entry to FT and transverse diameters of both VA and FT were measured at the point of entry. It was found that, among males, the VA originated from the truncus brachiocephalicus on the right side in only 1 patient and from the aortic arch in 2 patients on the left side. Left VA emerging from the aortic arch was observed in 2 females. The right VA was found to enter the FT at C3 in 1 male, at C4 in 6 patients (5 males, 1 female), at C5 in 19 patients (3 males, 16 females), and at C6 in 300 patients (141 males, 159 females). The left artery entered the FT at C5 in 23 patients (9 males, 14 females) and at C6 in 298 patients (141 males, 157 females). Looking at the relationship between variations of VA origin and the levels of entry to the FT, it was observed that only one of the left VAs originating from the arcus aorta entered the FT at C6 and at C5 in all others. On the right side, there was only one VA originating from the truncus brachiocephalicus, which entered the FT at C3. Of the remaining 248 VAs originating from the subclavian artery, 5 VAs entered the FT at C4, 14 VAs at C5 and 229 VAs at C6. The measurements of VA diameters showed right VA hypoplasia in 14 patients and left VA hypoplasia in 17 patients. Also, the right VA dominance was found in 110 patients and the left VA dominance in 128 patients. A moderate, positive correlation was observed between VA and FT diameters in both sides. A regression analysis showed that a 1 mm change in the right VA diameter was associated with a 75% change in the FT diameter and a 1 mm change in the left VA diameter caused a 72% change in the FT diameter. An understanding of VA variations and FT morphometry is crucial for informed clinical practice. This will clearly affect the success rates of physicians in the diagnosis and treatment of pathologies involving cervical region. The presence of any VA variation in a patient should be investigated on computed tomography or magnetic resonance imaging images prior to surgery.

Association of Left Vertebral Artery Hypoplasia with Posterior Circulation Stroke and the Functional Outcome of Patients with Atrial Fibrillation-Related Cardioembolic Stroke.

A cardiogenic embolus could reach the posterior circulation through the right vertebral artery because of a relatively larger diameter in cases of left vertebral artery hypoplasia. Hence, we investigated whether left vertebral artery hypoplasia is associated with cardiac embolisms with atrial fibrillation in the posterior circulation and its functional outcomes. In this monocentric retrospective study, patients with acute cardioembolic stroke with atrial fibrillation were enrolled and underwent CT or neck MRA, which visualized the aortic arch and subclavian arteries. The laterality and size of vertebral artery hypoplasia were recorded. Posterior circulation stroke, basilar artery occlusion, and the functional outcomes after 3 months were investigated. This study included 407 patients; the patients with left vertebral artery hypoplasia experienced a higher rate of posterior circulation stroke (19 versus 73; 42.2% versus 20.2%; P = .001) and basilar artery occlusion (5 versus 10; 11.1% versus 2.8%; P = .005) than the patients without left vertebral artery hypoplasia. Multivariate analysis revealed that left vertebral artery hypoplasia showed an association with lower odds of achieving a good functional outcome 3 months after the stroke (OR = 0.4; 95% CI, 0.2-0.9; P = .027). Patients with cardioembolic stroke and left vertebral artery hypoplasia had posterior circulation stroke, basilar artery occlusion, and poor functional outcomes after 3 months.

COMPUTED TOMOGRAPHY IN THE DIAGNOSIS OF A RARE ANOMALY OF BRACHIOCEPHALIC ARTERIES

After presentation of focal neurologic symptoms due to acute or chronic ischemic brain disease all patients should undergo complex examination in order to identify the source that changed hemodynamics and define management strategy. We present a clinical case of multiple aortic and brachiocephalic arteries anomalies in patient with complaints for dizziness and hearing noise. Computed tomography revealed right aortic arch with anomaly of brachiocephalic vessels branching, hypoplasia of left common carotid artery, agenesis of left internal carotid artery with «adult” type of collateral supply, hypoplasia of left vertebral artery, fusiform aneurysm of left posterior cerebral artery and also right internal carotid artery tortuosity in extracranial segment. Perfusion computer tomography showed symmetric cerebral flow. Computed tomography enables to assess different vascular changes in patients with brachiocephalic arteries anomalies and therefor to optimize treatment strategy.

Morphologic features of the aortic arch and its branches in the adult Chinese population

ObjectiveThe prevalence of various aortic arch branching patterns has not been established in Chinese people. Little is known regarding the underlying associations among age, sex, aortic arch type, branching variants, and even vertebral artery (VA) dominance (VAD) or VA hypoplasia (VAH). Thus, this study aimed to determine the prevalence of variations in aortic arch branching and types of arches in a Chinese population and to evaluate the associations among age, sex, aortic arch type, branching variants, and asymmetric VAs. MethodsThis retrospective study included 2370 patients (1348 men) who underwent thoracic enhanced computed tomography. Two observers independently evaluated the computed tomography images for aortic arch branching patterns, arch type, and the V1 segment caliber of the VA. ResultsA normal aortic arch branching pattern, classified as type A, was found in 1985 patients (83.8%). The remaining 385 patients (16.2%) with variations in arch branching were classified as types B through E according to the prevalence and general morphology of the aortic arch. The male-to-female ratio in patients with arch branching types B through E was significantly lower than that in patients with the normal type A pattern (0.87 vs 1.43; P < .01). We further identified that a steep aortic arch was significantly associated with age and sex. From the types I to III arch, the mean age was 55.4 ± 12.3, 60.9 ± 10.7, and 65.2 ± 9.9 years, and the male-to-female ratio was 685/653, 480/297, and 183/72, respectively. We also found that the left VA, which directly originated from the arch, was associated with right VAD and left VAH. ConclusionsThe incidence of variations in arch branching is higher in women. Advanced age and male sex are risk factors for a steep aortic arch. The left VA directly originating from the arch is strongly correlated with right VAD and left VAH.

Cervical spondylosis: a rare and curable cause of vertebrobasilar insufficiency

Spondylotic vertebral artery (VA) compression is a rare cause of vertebrobasilar insufficiency and stroke. A 53-year-old man experienced multiple brief vertebrobasilar transient ischemic attacks (TIAs) and strokes, not apparently triggered by neck movements. Brain magnetic resonance imaging (MRI) documented consecutive infarcts, first in the left then right medial posterior inferior cerebellar artery (PICA) territories. Angiography showed two extracranial right vertebral artery (VA) stenoses, left VA hypoplasia, absence of left PICA and a dominant right PICA. Computed tomography angiography revealed right VA compression by osteophytes at C5-C6 and C6-C7 levels. No further vertebrobasilar insufficiency symptoms occurred in the 65 months following VA surgical decompression. Our literature review found 49 published surgical cases with vertebrobasilar symptoms caused by cervical spondylosis. Forty cases had one or more brief TIAs frequently triggered by neck movements. Three cases presented with stroke without prior TIA, with symptoms suggesting a top of the basilar artery embolic infarcts (one combined with a PICA infarct). Six cases had both TIAs and minor stroke. VA compression by uncovertebral osteophytes at the C5-C6 level was common. Dynamic angiography done in 38 cases systematically revealed worsening of VA stenosis or complete occlusion with either neck extension or rotation (ipsilateral when specified). Contralateral VA incompetence was found in 14 patients. Spondylotic VA stenosis can cause hemodynamic TIAs and watershed strokes, especially when contralateral VA insufficiency is combined to specific neck movements. Low-amplitude neck movement may suffice in severe cases. Embolic vertebrobasilar events are less frequent. VA decompression from spondylosis may prevent recurrent ischemic episodes.

Right subclavian steal syndrome in a patient with aberrant right subclavian artery, common carotid trunk and hypoplastic left vertebral artery

Introduction: Subclavian steal syndrome refers to the reversal of vertebral blood flow in the setting of proximal subclavian or innominate artery severe stenosis or occlusion resulting in the symptoms of vertebrobasilar insufficiency related to exercise of the upper extremities. It is more common on the left side. Case report: We reported a case of subclavian steal syndrome on the right side in a patient with aberrant right subclavian artery (ARSCA), hypoplastic left vertebral artery and common carotid trunk (CCT) branching in to the left and right common carotid arteries. Conclusion: Till now, combination of ARSCA, CCT and left vertebral artery hypoplasia in the same person has not been reported and this combination causes ischemia in large area of brain if the patient develops hemodynamically significant stenosis or occlusion in both CCT and ARSCA proximal to the origin of right vertebral artery.

Hypoplasia of Left Vertebral Artery with Intimal Fibromuscular Dysplasia in a Korean Woman

We found a case of hypoplasia of vertebral artery with fibromuscular dysplasia in an 82-yr-old Korean female cadaver during a routine dissection course. In the present case, intracranial hypoplasia in left vertebral artery and bilateral origin of posterior inferior cerebellar artery at the vertebrobasilar junction were recognized. Histopathologically, left vertebral artery showed intimal type of fibromuscular dysplasia both in its extracranial and intracranial courses. These results indicate that the association of fibromuscular dysplasia and hypoplasia does exist in the vertebral artery, although the etiologies are not verified yet.

Letters to the Editor

4 June 2008 Dear Editor, PHACE SYNDROME: A CONSTELLATION OF CEREBRAL AND CARDIOVASCULAR ANOMALIES AND SEGMENTAL HAEMANGIOMAS PHACE syndrome is an uncommon neurocutaneous syndrome that manifests with multi-system involvement. It refers to the association of large, plaque-like, ‘segmental’ haemangiomas of the face, posterior fossa brain malformations, arterial cerebrovascular anomalies, cardiovascular anomalies, eye anomalies and ventral developmental defects.1 This letter describes a male baby who was born to a 41-year-old mother by elective section at term gestation and who weighed 2.88 kg. A prenatal diagnosis of posterior fossa malformation had been made at a 19-week anomaly scan. The infant was delivered breech by LSCS with forceps lift-out and was noted to have extensive bruising on left side of the face with an ipsilateral facial palsy. Over the next week the bruising was replaced by fine telangiectasia, which became darker and evolved into a confluent segmental facial haemangioma in the distribution of trigeminal cranial nerve extending into the oral cavity (Fig. 1). The important differential diagnosis at this stage was Sturge-Weber syndrome. Left sided segmental haemangioma with oral mucosal extension. MRI brain was consistent with Dandy Walker malformation. In addition, a soft tissue mass encircling cranial nerves VI and VII (possible acoustic neuroma, Fig. 2) along with hypoplasia of left vertebral artery was noted. The facial haemangioma was seen to extend internally to the left cavernous sinus, the extraconal spaces of the left eye and the superior mediastinum. While carotid Doppler showed no evidence of stenosis, the echocardiogram showed features consistent with coarctation of aorta. The ophthalmology review was unremarkable, showing no evidence of raised intraocular pressure or retinal detachment/optic neuropathy. He was started on laser therapy for the surface hemangioma after which it showed signs of gradual resolution. He was readmitted at 8 weeks of age with stridor and bronchoscopy revealed a large sub-glottic haemangioma obstructing most of the airway, which was managed by placement of a tracheostomy tube. MRI brain showing soft tissue mass encircling VI and VII nerves. While the acronym PHACE (OMIM 606519) was suggested by Frieden in 1995,2 the exact incidence of PHACE syndrome is unknown. Pathogenesis too is unknown, while the constellation of anomalies generally represents a ‘developmental field defect’, whereby an insult in embryogenesis at a critical time gives rise to similar developmental outcomes.3 The timing of these errors in morphogenesis occurs early, probably between 3 and 12 weeks of gestation, prior to or during early vasculogenesis. The syndrome represents a spectrum of disease, with few infants manifesting the entire constellation of anomalies, some components appearing later. The marked female preponderance (>80%) suggests a possibility of X-linked inheritance with lethality in males.1 Both sporadic and X-linked or autosomal inheritance patterns are reported, the X-linked form being typically bilateral and diffuse, and often associated with a mutation of filament A gene (FLNA) on Xq28.4 The hallmark of PHACE syndrome, a large, segmental facial haemangioma, may involve one to several facial dermatomes, and an early presentation may be mistaken for the port wine stain associated with the Sturge-Weber syndrome. Structural and cerebrovascular brain malformations occur in at least half. Posterior fossa malformations, including the Dandy-Walker complex, are the most common, and others include agenesis of corpus callosum and polymicrogyria. Developmental delay is a common association. Cerebrovascular defects present primarily as carotid artery anomalies, but also include aberrant/anomalous origins and aneurysm of cerebral vessels. The cerebrovascular anomalies, especially carotid artery anomalies, are of particular concern because of predisposition to progressive arterial occlusion and stroke.5, 6 Cardiac anomalies include coarctation of the aorta and septal defects, while ophthalmologic anomalies include retinal vascular abnormalities, optic nerve atrophy, and colobomas, among others. Infants with PHACE syndrome could represent up to 20% of infants with segmental facial hemangiomas, and both progressive and regressive vascular phenomena may occur in this syndrome.1 The most common therapeutic option directed at regression of haemangioma is prednisolone/ methylprednisolone, while others include topical steroids, pulsed dye laser, interferon alpha, vincristine, excision surgery and wound care.1 To summarise, a segmental hemangioma may be an initial presentation of PHACE syndrome, and a high index of suspicion and thorough investigation would optimise management.

A case of intimal hyperplasia induced by stenting for vertebral artery origin stenosis: Assessed on intravascular ultrasound

We report a case of proximal vertebral artery restenosis following stent placement. Intravascular ultrasound study helped delineate its characteristics. A 69-year-old man was admitted because of dysarthria and dysphagia. Angiography revealed hypoplasia of left vertebral artery (VA) and remarkable stenosis of the proximal right VA with inadequate collateral flow from the anterior circulation. Balloon angioplasty and stent placement at the VA was performed to an excellent angiographic result with recovery of neurological symptoms. His condition deteriorated six months later due to intimal hyperplasia, which we evaluated by intravascular ultrasound (IVUS). Balloon angioplasty was then performed. Stent placement may induce intimal hyperplasia and IVUS is useful to assess the lesion.