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

Secondary Benefits of Microsurgical Intervention on the Vertebral Artery (V1 Segment) for Refractory Vertebrobasilar Insufficiency: Alleviation of Parkinsonism-Like Symptoms

OBJECTIVE

The objective of this study was to investigate the outcomes of microneurosurgical interventions on V1 segment of the vertebral artery in patients with refractory vertebrobasilar insufficiency (VBI) due to dolicoarteriopathy and external compressions and to assess the secondary benefits of Parkinsonism-like symptoms.

METHODS

Retrospective analysis encompassed 101 patients treated for vertebral artery dolicoarteriopathy or compression-related refractory VBI from 2016 to 2023. Of these, 16 patients exhibited drug-resistant Parkinsonism-like symptoms. The diagnostic evaluation included cerebral computed tomography/magnetic resonance angiography or digital subtraction angiography and brain computed tomography or magnetic resonance perfusion studies, corroborated by preoperative and 6- and 12-month postoperative Movement Disorder Society-Unified Parkinson's Disease Rating Scale Part 3 assessments. Data were analyzed through Turkey's "E-nabız" system, employing Stata16 for statistical scrutiny.

RESULTS

A significant reduction in Movement Disorder Society-Unified Parkinson's Disease Rating Scale scores was observed (preoperative: 26.75±10.91; 6 months: 23.09±9.24; 12 months: 22.5±8.73; P < 0.001). Postoperative follow-up denoted that 43.7% of patients ceased medication and 50% reduced antiparkinsonian drugs. The microneurosurgical approach resulted in complete remission of VBI-related symptoms in 84.6% of patients, with the rest showing partial or marked improvement. At 6 months postoperation, perfusion studies revealed posterior border zone or cerebellar perfusion enhancements in 81% (13 out of 16) of patients, with full symptom resolution, while the remaining 19% (3 out of 16) showed partial perfusion and clinical improvements, particularly in regions supplied by the posterior cerebellar artery or posterior inferior cerebellar artery. The absence of operative mortality and minimal transient morbidities underscored the procedure's safety.

CONCLUSIONS

Microneurosurgery for vertebral artery anomalies in refractory VBI patients, particularly those with concomitant parkinsonian-like syndromes, has demonstrated potential in symptom remission and medication reduction.

Kinking, coiling and diameters of vertebral artery first segment and their relationships to sex and side

INTRODUCTION

Recent information on tortuosity in the prevertebral (V1) segment of the vertebral artery is based on case reports rather than systematic data on its presence, types, diameters, and sex- or left-right differences.

Basilar Artery Occlusion Caused by Extracranial Vertebral Artery Dissection on Its Entry into the Transverse Foramen of the C6 Vertebra: Case Report

Objective

Basilar artery occlusion (BAO) is an infrequent form of acute life-threatening stroke and may occur secondary to vertebral artery dissection (VAD). VAD, which occurs spontaneously and sometimes results from mechanical stress or blunt force trauma to the neck, sometimes occurs in the V1-V2 junction, but there are not many reported cases of those. Herein, we report a pictorially illustrative and clinically informative case of VAD in the V1-V2 junction following BAO.

Case Presentation

The patient was a 27-year-old woman who was transferred to our hospital with abrupt severe unconsciousness. On admission, she presented with generalized convulsions and respiratory arrest, and pan-scan CT and CTA indicated BAO. We performed mechanical thrombectomy and achieved recanalization of the basilar artery, and she was diagnosed with BAO secondary to the right VAD at the entry of the C6 transverse foramen (V1-V2 junction). In hindsight, she had scapula and back pain before the onset. She recovered with a modified Rankin scale score of 3 after 90 days from the onset.

Conclusion

VAD sometimes occurs at its entry into the transverse foramen of the C6 vertebra. In this case, VAD may be affected by minor trauma and potentially histological fragility due to the embryonic development process. Although BAO is sometimes difficult to diagnose because it presents with various symptoms, BAO secondary to VAD should be considered in cases of abrupt severe unconsciousness preceded by neck, scapula, or back pain in young and healthy persons.

Mapping of Anatomic Variants of the Proximal Vertebral Artery in Relation to Embryology

BACKGROUND AND PURPOSE

Variations in the origins and courses of the vertebral arteries are relatively rare but may be clinically meaningful. We hypothesize a relationship between variant origins of the vertebral arteries and their levels of entry to the foramina transversaria.

MATERIALS AND METHODS

In this retrospective study of CT angiograms, we document the frequency and types of vertebral artery variants, correlating origins with levels of entry to the foramina transversaria.

RESULTS

Vertebral artery variants were observed in 18.7% of a sample of 460 CT angiograms of the neck. Right-sided variants were less common than left (44.2% versus 68.6%, with 12.8% bilateral) and more common than previously thought. The most common variant on both sides was a variant origin proximal to the normal vertebral artery origin and entry at C5. Most right vertebral arteries originating within 2 cm of the origin of the right subclavian artery and left vertebral arteries originating between the left common carotid and subclavian arteries were "high-entry" variants. Most "low-entry" variants, entering at C7, took origin from the arch just distal to the left subclavian artery or at a common origin with the costocervical trunk. Multiple origins or accessory vertebral arteries were also described, and each moiety followed the same rules described for single origins. A map of vertebral artery origins mirrored the map of aortic arch embryology.

CONCLUSIONS

Vertebral artery variants follow certain well-defined patterns that correlate with the embryology of the aortic arch and great vessels.

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.

Anatomical variation in the branching pattern of the aortic arch: a literature review

Background

Many anatomical variations of the branching pattern of the aortic arch have been documented in the literature. These find their origin in alterations to the embryological development of the arch and have significant implications for surgical and radiological interventions.

Methods

Embase and Medline database searches were carried out in June 2021 and identified 1197 articles, of which 24 were considered eligible.

Results

Twenty-eight variations were found. The prevalence of the six main variations found is as follows: normal configuration (61.2–92.59%); bovine arch type 1 (4.95–31.2%); bovine arch type 2 (0.04–24%); origin of left vertebral artery (0.17–15.3%); aberrant right subclavian artery (0.08–3.33%); thyroid ima artery (0.08–2%). Concomitant variations present in conjunction with these variations are also documented, as were other variations which could not be classified into these six groups.

Conclusions

Anatomical variations in the branching pattern of the aortic arch are present in over one-third of individuals in some populations. These are important pre- and intra-operatively during thoracic, neck and thyroid surgery. A greater effort should be employed to construct an official classification to facilitate greater understanding among clinicians.

Employing the London Atlas in the Age Estimation of a Select South African Population

Dental age estimation in the living and deceased is a fundamental aspect of forensic sciences, civil cases, medico-legal proceedings and clinical dentistry. Accordingly, this study aimed to validate the accuracy and reproducibility of the London Atlas in a select South African sample of KwaZulu-Natal. In this cross-sectional study, 760 digital panoramic radiographs (n = 760) aged between 5.00 and 23.99 years were retrospectively reviewed through consecutive sampling. Each radiograph was assessed and assigned a dental age in accordance with the London Atlas of Human Tooth Development and Eruption by AlQahtani et al. (2010). The London Atlas overestimated age with a mean difference of −0.85 to −1.26 years in the selected South African sample of KwaZulu-Natal. A statistically significant difference between the chronological and estimated dental ages was recorded. Furthermore, the South African Black and Indian males had a higher overestimation of age than their female counterparts, with a mean difference of 0.13 and 0.07 years, respectively. This overestimation was less in the South African Indian population in comparison to the SA Black population. This outcome resulted in the creation of the KZN population- and sex-specific charts and atlases for the two selected cohorts of KwaZulu-Natal. The KZN Atlases were found to be more accurate in the selected sample, with a mean absolute error of 0.57 years and no statistically significant differences between the chronological and estimated dental ages.

The Application of the Cameriere's Methodologies for Dental Age Estimation in a Select KwaZulu-Natal Population of South Africa

Background: The estimation of an individual’s age is a fundamental component of forensic odontology. Literary reports found that the efficiency of Cameriere methodology for age estimation varied among many population groups. Therefore, this study aimed to determine the applicability of the Cameriere methods to a select South African population of the KwaZulu-Natal (KZN) province. Materials and Methods: This cross-sectional retrospective study was conducted on 840 digital panoramic radiographs that met the inclusion criteria. Dental maturity was determined through the morphometric analysis of the seven left permanent mandibular and maxillary teeth in accordance with Cameriere et al. (2006). Moreover, the dental age was also calculated using the South African Black Bayesian formulae of the Cameriere method by Angelakopoulos et al. (2019). The paired sample t-test or Wilcoxon’s signed rank test assessed the significant difference between the chronological age and estimated dental age for the various formulae. A p-value < 0.05 was considered to be statistically significant. Results: The Cameriere et al. (2006) Italian formula and the South African Black Bayesian formulae of the Cameriere method by Angelakopoulos et al. (2019) underestimated and overestimated age in the South African Black and Indian population groups of the KZN province, respectively. Therefore, the authors generated a novel population-specific regression formulae (including and excluding third molars) using “step-wise regression analysis” and a “best-fit model” for the South African Black and Indian population groups of KZN. Conclusion: This study recommends that the population-specific formulae generated in this study be utilized in the KZN population to improve the accuracy of dental age estimation within this region.

Risk factors for in-stent restenosis after vertebral artery stenting of V1 segment: A systematic review and meta-analysis

OBJECTIVE

In-stent restenosis (ISR) remains a challenge in the treatment of vertebral artery V1 segment stenosis. The aim of this meta-analysis is to identify the risk factors of ISR.

METHODS

Studies eligible for inclusion criteria were found in PubMed, Embase, and Cochrane Library databases. Data related to risk factors of ISR were extracted from the included studies, and pooled analysis was performed when data of the same factor were available in ≥2 studies. Dichotomous outcomes were analyzed with odds ratios (OR) and continuous outcomes were analyzed with a weighted mean difference (WMD). The Stata 14.0 program was used for the meta-analysis.

RESULTS

A total of 11 studies involving 1356 patients were included in our analysis. Pooled analyses showed that younger age (p = 0.01; WMD= -1.958; 95% confidence interval [CI], -3.453 to -0.463) and V1 tortuosity (p = 0.004; OR = 4.145; 95% CI, 1.56-11.012) significantly associated with higher risk of ISR in V1 segment stenting. While bare-metal stents, stent diameter and length, diabetes mellitus, coronary artery disease, and smoking were not found to increase ISR rates.

CONCLUSIONS

This meta-analysis showed that young age and V1 tortuosity increase the ISR rates after vertebral V1 segment stenting.