Are the anomalous vertebral arteries more hypoplastic?: retrospective linear mixed model approach

The Vertebral Artery: A Systematic Review and a Meta-Analysis of the Current Literature

(1) Background. The anatomical variations of the vertebral arteries (VAs) have a significant impact both in neurosurgery and forensic pathology. The purpose of this study was to evaluate the variational anatomy of the vertebral artery. We evaluated anatomical aspects regarding the V1 and V2 segments of the VA: origin, course, tortuosity, hypoplasia, and dominance, and established the prevalence of each variation. (2) Methods. We conducted a systematic search in PubMed and Google Scholar databases, up to December 2022. Sixty-two studies, comprising 32,153 vessels, were included in the current meta-analysis. We used a random-effects model with a DerSimonian-Laird estimator. The confidence intervals were set at 95%. The heterogeneity between studies was assessed using I². The funnel plot and Egger's regression test for plot asymmetry were used for the evaluation of publication bias. Statistical significance was considered at p < 0.05. (3) Results. The most common site for the origin of both VAs was the subclavian artery. The aortic arch origin of the left VA had a prevalence of 4.81%. Other origins of the right VAs were noted: aortic arch (0.1%), right common carotid artery (0.1%), and brachiocephalic trunk (0.5%). Ninety-two percent of the VAs entered the transverse foramen (TF) of the C6 vertebra, followed by C5, C7, C4, and least frequently, C3 (0.1%). Roughly one out of four (25.9%) VAs presented a sort of tortuosity, the transversal one representing the most common variant. Hypoplasia occurred in 7.94% of the vessels. Left VA dominance (36.1%) is more common, compared to right VA dominance (25.3%). (4) Conclusions. The anatomy of the VA is highly irregular, and eventual intraoperative complications may be life-threatening. The prevalence of VA origin from the subclavian artery is 94.1%, 92.0% of the VAs entered the TF at C6, 26.6% were tortuous, and 7.94% were hypoplastic.

Clinical Characteristics of Patients with Vertebral Artery Hypoplasia

Vertebral artery hypoplasia (VAH) belongs to the relatively frequent Doppler ultrasonography (US) findings. However, its clinical significance remains controversial. This was a retrospective study analyzing clinical data of patients undergoing US because of cerebrovascular disease in a single academic neurology center. In the dataset of 2500 US examinations, 80 individuals with VAH (VA diameter < 2.0 mm) were identified (3.2% of all patients). Patients with significant vertebral artery asymmetry (SVAA, difference in VA diameters > 1.0 mm) (n = 80) and patients with normal VA diameter (n = 80) were also recruited. Clinical parameters including clinical signs and symptoms, concomitant diseases, imaging findings and the hospitalization outcome were compared between groups. The frequency of vertigo was highest in VAH group. Ischemic lesions of the cerebellum were found in 10% of VAH patients, 16% of SVAA patients and 5% of control subjects. Neurological deficits improved in over 60% of patients in each group, whereas ca. 30% of patients remained in a stable neurological status. The percentage of patients who deteriorated did not exceed 5% in any of the groups. The results of our study support a relatively high frequency of VAH. Our observations suggest coexistence of VAH with a higher frequency of neurological presentations associated with posterior arterial circulation of the central nervous system.

The Clinical Research Progress of Vertebral Artery Dominance and Posterior Circulation Ischemic Stroke

BACKGROUND

The diameters of the vertebral arteries on both sides are usually asymmetrical. Vertebral artery dominance (VAD) and congenital vertebral artery dysplasia are derived from the asymmetry of the vertebral artery diameters on both sides. They are usually regarded as normal congenital vascular variations and have no practical clinical significance.

SUMMARY

Recently, several clinical studies have found that VAD is a risk factor for posterior circulation ischemic stroke (PCIS). The existence of VAD is clinically significant for the occurrence of PCIS, and it is recognized by an increasing number of clinicians. Key Messages: This article reviews the frequency and evaluation methods of VAD, its correlation with PCIS, and its mechanism.

Imaging Challenges in the Diagnosis of Anatomical Variations of the Supra-Aortic Vessels: A Case Report and Review of Literature

A 73-year-old woman was referred to our Cardiology Department due to recurrent headaches and dizziness. She had a history of hypertension of 10 years. In the territorial hospital, left internal carotid artery significant stenosis was suspected. Neurological examination and laboratory tests were normal. A neck vascular ultrasound was performed, showing a low bifurcation of the left common carotid artery (CCA) and a hypoplastic left internal carotid artery (ICA) with a sinuous path at the cervical level. Therefore, a computed tomographic (CT) angiography examination of the head and neck vessels was performed. The images confirmed the presence of a hypoplastic left ICA, anatomic variation in the left CCA, and also showed that the left vertebral artery (VA) was stemming directly from the aortic arch, exhibiting a kinking trajectory.

Radiological anatomy of the intracranial vertebral artery in a select South African cohort of patients

The intracranial segment of the vertebral artery (VA) is the unique part of the artery where the two VAs join to form a single vascular channel, viz. the basilar artery. In addition to this typical description, anatomical variations have been described; the presence of anatomical variation has been associated with some pathological processes, neurological complications, and the risk of vascular diseases in the posterior circulatory territory. We evaluated the typical anatomical features and variations of the VA4 component of the VA in a South African population to provide useful data on the prevalence of variation and morphometry of the distal VA. The study is an observational, retrospective chart review of 554 consecutive South African patients (Black, Indian, and Caucasian) who had been examined with multidetector computed tomography angiography (MDCTA) from January 2009 to September 2019. We observed various anatomical variations in the VA4 segment of the VA. We report the incidence of VA hypoplasia, hypoplastic terminal VA, and atresia. Fenestration and duplicate posterior inferior cerebellar artery (PICA) origin were also observed. The left intracranial VA was significantly larger than the right. Our study shows that anatomical variation of the intracranial VA is common in the population studied, with a total prevalence of 36.5%. Understanding the patterns of anatomical variations of the VAs will contribute significantly to the interpretation of ischemic areas and diagnosis of various diseases in the posterior circulatory territory.

Extraforaminal Vertebral Artery Anomalies and Their Associated Surgical Implications: An Epidemiologic and Anatomic Report on 1000 Patients

OBJECTIVE

Extraforaminal vertebral anomalies involve entry at cervical transverse foramina other than at C6 and can appear with other anatomic variations along the V2 segment. Such unexpected vessel courses can have implications on surgical planning. We sought to evaluate the incidence of anomalous V2 segment entries, as well as their associations with vessel dominance, medialization, and C7 pedicle width.

METHODS

We conducted a retrospective study on 1000 consecutive computed tomography angiograms, documenting level and laterality of vessel of entry, as well as vertebral dominance patterns. Patients with rostral C4 anomalies were assessed for medialization. The pedicle widths ipsilateral to caudal C7 anomalies were compared with those of contralateral and matched controls.

RESULTS

A total of 157 patients were identified with extraforaminal entries, with 25 having bilateral findings. The most common alternative entry was at C5 (70.3%), followed by C4 (17.6%) and C7 (11.5%). Among patients with unilateral anomalies, there was an increased representation of contralateral vertebral dominance, relative to ipsilateral dominance (79.6% vs 20.4%, P < 0.0001). Among anomalous C4 entries, vertebral medialization was seen along the right (35%) and left sides (23.1%) spanning C6-T1. Among C7 anomalous entries there was no statistical difference in pedicle width.

CONCLUSIONS

Extraforaminal anomalies may be more frequent than previously reported and are important considerations during subaxial cervical spine surgery planning. Particular attention should be paid to the contralateral dominance pattern within this subgroup. In patients with anomalous V2 segment entries, adherence to the standard, anatomic landmarks remains desirable.

The right vertebral artery arising from the right common carotid artery: report of a rare case

Anomalous origins of the vertebral arteries are uncommon and generally associated with other abnormalities of the supra-aortic vessels. We present an extremely rare case where the right vertebral artery is arising from the right common carotid artery, with an absent brachiocephalic trunk, and the right common carotid artery as the first branch of the aortic arch followed by right subclavian artery, without any other abnormalities of the supra-aortic vessels. This vessel variation can affect endovascular procedures, surgical interventions and cause some unexpected clinical symptoms.

A case of aberrant bilateral vertebral arteries orgin presenting with right VA dissection

Background

Knowledge of variations in the origin of vertebral artery (VA) is indispensable to vascular surgeons. Aberrant origin of vertebral artery on either side is an uncommon finding. There are unilateral and bilateral variability in VA origin.

Case presentation

We present a case of vertebral artery dissection who was found to have bilateral VAs aberrant origin. The right VA took origin from the right common carotid artery (CCA) which is a completely a rare finding, and the left VA originated from the arch of aorta.

Conclusion

Unlike most similar reported cases, the VA diameter at origin was larger on the left than on the right side. The possible embryological mechanism is discussed.

Challenging case of muscle bridge; a 15-year follow-up of a patient

BACKGROUND

Anatomically myocardial bridging (MB) consists of either superficial myocardial fibers that traverse over the LAD or deep fibers that encircle the coronary artery. In this study, we present a patient with myocardial bridging, who was primarily diagnosed with coronary artery disease which did not properly respond to full-dose medical treatment but benefited from coronary artery bypass graft (CABG).

CASE PRESENTATION

In 2017, a 53-year old man was referred to Tehran Heart Center (THC) with complaint of typical chest pain (TCP). In 2003 he had TCP and underwent coronary angiogram (CAG), due to positive non-invasive tests. Muscle-bridge in LAD was diagnosed. In 2007, he was symptomatic and another CAG was done, and percutaneous coronary intervention (PCI) with stenting was performed. In 2008 he became symptomatic and his interventionist, decided to perform another CAG. At that time, he had CABG. He was asymptomatic until 2015, he referred to us with the same TCP and we decided to perform CAG for the fourth time. After two years, again another PCI was done due to in-stent restenosis.

CONCLUSION

Revascularization should be considered in MB refractory to medical treatment. However, coronary perforation, in-stent restenosis and graft failure are major concerns.

Isolated anomalous origin of the vertebral artery from the common carotid artery

Anomalous origins of the vertebral arteries are uncommon and typically associated with other abnormalities of the great vessels. We present a case of an isolated origin of the right vertebral artery from the ipsilateral common carotid artery detected using magnetic resonance angiography. Such variants can significantly affect endovascular and surgical planning.