A systematic classification of the left-sided aortic arch variants based on cadaveric studies' prevalence

A Computed Tomography Study on the Prevalence of Lusorian Artery Among Hungarian Adults

Introduction The aberrant right subclavian artery (ARSA), also called as lusorian artery (LA) is a developmental anomaly that exists in conjunction with a right non-recurrent laryngeal nerve (NRLN) in almost all cases. The average prevalence of such a vascular variation is estimated as 1%, although, studies have reported very different population means. Up to date, there is no available data on the frequency of this pattern in the Hungarian population. It can be treated as an indirect marker of a NRLN. Any preoperative information on the course of the inferior laryngeal nerves can help surgeons reduce the risk of an iatrogenic injury during thyroidectomies, especially in an environment where access to intraoperative neuromonitoring is limited. Objectives The primary aims were to determine the prevalence of an ARSA, predict the existence of an NRLN in the Hungarian population, and provide demographic analysis. Methods A retrospective, computed tomography-based study was carried out. Demographic description and statistical analysis were provided where applicable. Detected anomalous vasculatures were visualized with 3D segmentation, and images were interpreted. Results The imaging database review identified three patients with ARSA out of 686 eligible recordings, resulting in a frequency of 0.437% in the study population. All three patients were female and had a retroesophageal LA. Two of them had a Kommerell's diverticulum. One patient had common carotid arteries with a single origin. Conclusions The frequency of an ARSA and a concomitant NRLN among Hungarians fits into the results of recent meta-analyses. Preoperative assessment of this anomaly may reduce vocal cord complication rates of thyroidectomies.

Morphological Aspects of the Aberrant Right Subclavian Artery-A Systematic Review of the Literature

BACKGROUND

The aberrant origin of the right subclavian artery (ARSA), also known as the lusoria artery, is a congenital malformation with an incidence of 0.5-4.4%. Most cases are incidental due to minimal clinical manifestations. Computer tomography (CT) is important in diagnosing and evaluating these patients.

MATERIALS AND METHODS

We conduct a computerized search in two databases, PubMed and EMBASE, for articles published between 1 January 2022 and 31 December 2023, PROSPERO code: CRD42024511791. Eligible for inclusion were case reports and case series that presented the aberrant origin of the right subclavian artery. The main outcome was the highlighting of the morphological types of ARSA. In this context, we proposed a new classification system of this anomaly. The secondary outcome was the evaluation of the demographic distribution of the lusoria artery.

RESULTS

Our search identified 47 articles describing 51 patients with ARSA. The typical course for ARSA is retroesophageal, being registered in 49 out of 51 patients. This malformation is frequently associated with Kommerell diverticulum (15 out of 51), troncus bicaroticus (7 out of 51), and aberrant origins of the right vertebral artery (7 out of 51). We observed a higher incidence of the condition among women (32 out of 51) compared to men (19 out of 51). From a demographic point of view, ARSA is more frequent in the "44 to 57 years" and "58 to 71 years" age ranges.

CONCLUSIONS

ARSA is a congenital malformation resulting from a defect in the development of the aortic arches. The imaging studies such as computer tomography play a defined diagnostic role.

Considerations on the morphology of the thyroid ima artery

PURPOSE AND BACKGROUND

Detailed knowledge of the thyroid ima artery is essential for surgeons consequently we conducted an analysis investigating the arterial vasculature of the thyroid gland in 290 cases by dissection of formalin-fixed cadavers and by studying computed tomography angiographies.

METHODS

Our study was conducted on 82 cases obtained from the dissection of formalin-fixed cadavers while 208 cases were computed tomography angiographies. The following aspects were observed: the frequency of the thyroid ima artery, its origin, course, and diameter. All were studied, comparing right to left and according to sex.

RESULTS

Following the study of thyroid gland vasculature on a number of 290 cases, the thyroid ima artery was discovered in 16 cases (5.52% of cases), from which 3.45% of cases were in male subjects, and 2.07% of cases in female subjects. Of these, 4.14% of the total cases were left thyroid ima artery, and 1.38% of cases were on the right, found only in female subjects. In 5.17% of the total cases, the thyroid ima artery originated from the aortic arch, of which 3.45% were in the male sex and 1.72% were in the female sex. In one case only (0.35%) in the female sex did the thyroid ima artery originate from the brachiocephalic trunk. In 2.76% of cases, the thyroid ima artery existed with a left-sided inferior thyroid artery originating from the subclavian artery, either directly or from a thyrocervical trunk.

CONCLUSIONS

The thyroid ima artery has proven to be one of the highly variable arteries in terms of its presence and origin and the knowledge surrounding it is useful for surgical interventions.

A Rare Case of Thyroidea Ima Arising From the Internal Thoracic Artery and Reaching Up to the Parathyroid Gland

The thyroidea ima artery (TIA), also known as the Neubauer artery, is a variable artery that takes part in the blood supply of the thyroid gland. The overall prevalence rate of the thyroidea ima artery is 3.3%. Though it most commonly branches off the brachiocephalic trunk or the arch of the aorta, the artery has a highly variable origin point. Herein, we present a rare case of a thyroidea ima originating from the left internal thoracic artery, found during routine dissection of a Caucasian, 76-year-old, male, formalin-fixed cadaver. The artery is a normal finding during embryological development as a part of a more extensive network of vessels supplying the thyroid gland. The latter undergoes significant remodeling, and only four superior and inferior thyroid arteries remain. Thus, the presence of the thyroidea ima is considered to be due to changes in the said remodeling process. Due to its course, anteriorly to the trachea, the thyroidea ima artery might pose problems during different surgical procedures regarding the inner anterior region of the neck, such as tracheotomy, thyroidectomy, laryngeal transplantation, and selective embolization of the thyroid arteries (SETA). Furthermore, complications during the operative treatment of parathyroid conditions and mediastinal bleeding are to be expected. The variable presence and origin of the thyroidea ima have clear and significant clinical and surgical implications. They must be considered when procedures in the neck's anterior region occur.

Anatomical structures, cell types, and biomarkers of the healthy human blood vasculature

More than 150 scientists from 17 consortia are collaborating on an international project to build a Human Reference Atlas, which maps all 37 trillion cells in the healthy adult human body. The initial release of this atlas provided hierarchical lists of the anatomical structures, cell types, and biomarkers in 11 organs. Here, we describe the methods we used as part of this initiative to build the first open, computer-readable, and comprehensive database of the adult human blood vasculature, called the Human Reference Atlas-Vasculature Common Coordinate Framework (HRA-VCCF). It includes 993 vessels and their branching connections, 10 cell types, and 10 biomarkers. With this paper we are releasing additional details on vessel types and subtypes, branching sequence, anastomoses, portal systems, microvasculature, functional tissue units, mappings to regions vessels supply or drain, geometric properties of vessels, and links to 3D reference objects. Future versions will add variants and connections to the lymph vasculature; and, it will iteratively expand and improve the database as additional experimental data become available through the participating consortia.

Thyroidea ima artery multiple branching pattern over the trachea

PURPOSE

The current cadaveric report describes a rare case of a thyroidea ima artery (TIA) with multiple branching pattern over the trachea.

METHODS

A cadaver dissection of the neck and thorax region of a formalin-embalmed 90-year-old male cadaver of a body donor took place. The body donation was made after a signed informed consent.

RESULTS

The TIA variant originated from the brachiocephalic artery before its bifurcation into the right common carotid artery (CCA) and right subclavian artery (SCA). TIA further divided into three anterior and two posterior branches, with subsequent multiple division into smaller branches. All branches were located anterior and right side to the trachea. The anterior branches supplied the infrahyoid muscles and the posterior ones supplied the thyroid gland inferior lobes and the inferior parathyroid glands. The TIA coexisted with a brachiocephalico-carotid trunk, derived after the left CCA and brachiocephalic artery fusion.

CONCLUSION

The presence of multiple arterial branches over the trachea creates a high risk for excessive bleeding during tracheotomy or cricothyroidotomy.

Anatomical Variations in Aortic Arch Branching Pattern: A Computed Tomography Angiography Study

INTRODUCTION

Variations in the branching pattern of the aortic arch (AA) are common. Modification of intravascular stents should be considered taking into account these AA branching variations. Identification of supra-aortic branching types and frequencies is important for specialists planning surgery in this region. In endovascular interventions to the AA, aortic stent grafts should be modified according to the variations of the branching patterns of the AA. In any surgical intervention to the region where the supra-aortic branches are located, ignorance of the variations may cause unwanted injuries or complications.

METHODS

In this study, 699 computed tomography angiography (CTA) images were reviewed to investigate AA branching variations using the Horos software (an open-source image viewer). Four groups were constructed based on the number of branches emerging from the aortic arch, which were further divided into subtypes.

RESULTS

A total of 699 CTA images from 320 males and 379 females were included in this study. The usual AA branching pattern (type 3b1) was found in 68.5% of the patients. The combined prevalence of other eight branching patterns, designated as variations, was 31.5%. Variation types 1b1, 3b2, and 4b5 were identified in one patient each. Overall, types 2b1 and 2b2 had a prevalence of 28.3%. The type 2b3 variation was observed in 1.6% of the patients. The least common variations were type 4b1 (0.7%) and type 3b2 (0.1%).

CONCLUSION

The identification of variations in AA branching patterns by CTA prior to surgical or endovascular interventions involving the aortic arch is important. Thus, specialists planning interventions in this region need to be aware and have knowledge of atypical aortic branching patterns. Higher prevalence rates of AA branching patterns compared to previous studies were identified in the Turkish population in this study and therefore, a comprehensive, multicenter study is needed to determine the cause of this differential finding.

Prenatal genetic analysis of fetal aberrant right subclavian artery with or without additional ultrasound anomalies in a third level referral center

To evaluate the correlation between chromosomal abnormalities and fetal aberrant right subclavian artery (ARSA) with or without additional ultrasound anomalies (UAs). A total of 340 fetuses diagnosed with ARSA by ultrasound between December, 2015, and July, 2021, were included. All cases were subdivided into three groups: (A) 121 (35.6%) cases with isolated ARSA, (B) 91 (26.8%) cases with soft markers, and (C) 128 (37.6%) cases complicated with other UAs. Invasive testing was performed via amniotic fluid or cord blood karyotyping and chromosomal microarray analysis (CMA) in parallel, and pregnancy outcomes were followed. Karyotype abnormalities were identified in 18/340 (5.3%) patients. Karyotype abnormalities in Groups A, B, and C were 0/121 (0.0%), 7/91 (7.7%), and 11/128 (8.6%), respectively. CMA abnormalities with clinically significant variants were detected in 37/340 (10.9%) cases, of which 22q11.2 deletion syndrome and trisomy 21 accounted for 48.6% (18/37). The overall abnormal CMA with clinically significant variant detection rates in Groups A, B, and C were 3/121(2.5%), 13/91 (14.3%), and 21/128 (16.4%), respectively. There were significant difference in clinically significant CMA anomalies detection rate between Groups A and C (p < 0.05), as well as Groups A and B (p < 0.05). Comparing CMA to karyotyping showed a clinically significant incremental yield in Group C (7.8%, 10/128) compared to Groups A (2.5%, 3/121) and B (6.6%, 6/91) (p > 0.05). Fetal ARSA with additional UAs, concurred with cardiac and extra-cardiac anomalies, constitutes a high-risk factor for chromosomal aberrations, especially for pathogenic or likely pathogenic copy number variants.

Aberrant Right Subclavian Artery: Cadaver Case Report

While examining the anatomy of a cadaver in a medical school gross anatomy course, an aortic arch anomaly was discovered. This variant is consistent with an aberrant right subclavian artery (ARSA). In this variant the right subclavian artery branches from the most distal part of the aortic arch and runs both retrotracheal and retroesophageal as it courses to the right shoulder. This variant is a result of aberrant development of the aortic arch and may include presenting symptoms such as dysphagia and shortness of breath, if any at all. Additional to the ARSA exists a common bicarotid trunk and a direct branching of the left vertebral artery from the aortic arch, both of which are rare anomalies. The cadaver’s medical history includes dysphagia and stretched esophagus, although the severity is unknown. This case report draws attention to these rare anatomical anomalies and includes a discussion of the most common clinical presentation, and surgical implications of an aberrant right subclavian artery anomaly.

Common carotid artery medialization and fracture dislocation of the cervical spine

PURPOSE

To describe the management of the discovery of a retropharyngeal carotid artery in the context of a cervical dislocation.

DESCRIPTION OF THE CASE

A 68-year-old female presented acute neck pain and incomplete tetraplegia following a fall on the stairs. Radiographs, contrast-enhanced computed tomography scan and magnetic resonance of the cervical spine revealed a C5-C6 bi-articular dislocation. A detailed preoperative assessment of the images discovered a medialization of the left common carotid artery. An external reduction and a left anterior cervical approach allowed a careful management of the vascular variation and an anterior C5-C6 arthrodesis. At six months, a full neurological recovery was assessed and radiographs demonstrated successful fusion of the cervical arthrodesis.

DISCUSSION/CONCLUSION

Anatomical features such as medialization of the common carotid artery may affect patients with traumatic cervical spine injuries. The severity of the traumatic bone lesions should not overshadow the preoperative analysis of the adjacent anatomical structures encountered during the surgical approach, even in an emergency situation.

Hybrid repair of acute type B dissection with aberrant right subclavian artery and bicarotid trunk

Patients with type B aortic dissection (TBAD) often present as an emergency. Operative repair of TBAD can be indicated for selected patients in the setting of hemodynamic instability or rupture. Thoracic endovascular aortic repair of TBAD has achieved significant popularity. Variant aortic arch anatomy can present a significant clinical challenge in patients with an inadequate proximal landing zone for thoracic endovascular aortic repair. A three-stage, hybrid aortic arch debranching and endovascular repair of a ruptured TBAD in a patient with a bicarotid trunk and an aberrant right subclavian artery was successfully performed using a unique technical approach.

The left-sided aortic arch variants: prevalence meta-analysis of imaging studies

PURPOSE

To estimate the prevalence of the left-sided aortic arch (LSAA) variants, and the effect of possible moderators on variants' detection.

METHODS

A systematic online literature search was conducted. The pooled prevalence with 95% confidence intervals was estimated for the typical and atypical branching patterns to compare the overall proportions of different variants. Meta-regression analyses were performed to investigate the effect of the subjects' gender and geographical region, and the multidetector computed tomography (MDCT) scanner's technology on the estimated prevalence.

RESULTS

In total, 18,075 cases from 23 imaging studies were included and 33 different LSAA variants were detected. The estimated heterogeneity was statistically significant. Based on the estimated prevalence, approximately 77% of the population is expected to have the typical branching anatomy with sequence brachiocephalic trunk-left common carotid artery-left subclavian artery, and 23% variant branching patterns. Approximately 71%, 23%, 2%, and 0.1% of the atypical populations are expected to have two, four, three, and five emerging branches, respectively. The meta-regression analyses showed that the number of detector rows of the MDCT scanner, and the subjects' geographical region are statistically significant moderators of the estimated prevalence.

CONCLUSION

The current findings indicate that the prevalence of the LSAA variant branching anatomy is significantly affected by the subjects' geographical region and the MDCT scanner's technological improvement, with the advanced scanners to facilitate the detection of the aortic arch variants. However, due to the heterogeneity among studies, further research is required.

Prenatal Diagnosis of Bovine Aortic Arch Anatomic Variant

Fetal aortic arch development is an early and complex process that depends on many genetic and environmental factors. The final aortic arch varies greatly; it may take the form of a normal arch, anatomic variant (AAAV) with a common origin to that of the innominate artery and left common carotid artery (formerly known as “bovine aortic arch” (with an incidence of up to 27%)) or one of multiple pathological conditions. The present study aimed to establish the feasibility and impact of prenatal anatomic arch variants’ diagnosis. A retrospective study of 271 fetal second- and third-trimester anomaly scans was performed in our tertiary center. Examinations that evaluated the sagittal aortic arch were included and the branching pattern was assessed. Additionally, a literature data search based on the terms “common origin of innominate artery and left common carotid artery”, “bovine arch”, “bovine aortic” and “aortic arch anomalies” was performed. Results that referred to prenatal AAAV were retained and the papers evaluated. In our study, the AAA incidence was 1.93%, with 4 out of 5 cases being arch type B. All cases had minor associated conditions but a good postnatal outcome. An anatomic aortic variant with a common IA and LCCa prenatal diagnosis was found in a small number of studies; most of the cases described in pediatric and adult series were related to cardiac surgery for stenting, aneurysm or thoracic-associated diseases. The incidence of AAAV varied from 6 to 27% depending on the population studied (highest incidence in African individuals). The variant was highly associated with aortic dissection, pulmonary and cerebral embolism and increased risks of incidents during surgery. Diagnosing AAAV during a routine anatomic scan is feasible and diagnoses can be made when anomaly scans are performed. Awareness of the condition is important for postnatal surgery when other cardiac anomalies are found; this can prevent accidents with simple changes to the patient’s lifestyle, and, in the case of surgery, means we can adopt the correct surgical approach.

Prenatal diagnosis of aberrant right subclavian artery: a literature review

The primary aim of this review is to estimate the prevalence of ARSA both in euploid fetuses as well as in fetuses with Down Syndrome. Secondary objectives were to estimate the association of ARSA with cardiac anomalies and chromosomal defects, especially trisomy 21 and 22q11 deletion (DiGeorge Syndrome). The incidence of ARSA in normal population varies from 0.35% to 3.5%, based on different studies. Since the first reported association between ARSA and trisomy 21 in 2015 until today, several studies have emerged to confirm different degrees of this correlation. Indeed, ARSA appears to be a clinically useful prenatal ultrasound marker for trisomy 21. Particularly, most recent studies concluded that ARSA as a non-isolated finding can be used as screening for Down syndrome. However, when ARSA is an isolated finding, various studies proved that there is no significant correlation with Down syndrome. Apart from these, ARSA appears to be associated with other chromosomal abnormalities, such as 22q11 deletion, cardiac defects and other morphological anomalies. As a conclusion ARSA should be characterized as isolated or non-isolated, as the non - isolated ARSA appears to be a clinically useful marker of Down syndrome and thus, additional testing is required when diagnosed.

Anatomical variations of the aortic arch branching pattern using CT angiography: a proposal for a different morphological classification with clinical relevance

The aortic arch (AA) branching pattern variations are usually asymptomatic, but they may lead to complications during cardiovascular procedures. In this retrospective study, we aimed to analyze the frequency of anatomical variations of the AA and to develop a different approach of morphological classification based on radiological criteria. 1026 computed tomography angiography scans of adults were evaluated and the presence of left-sided (LAA) and right-sided (RAA) AA were determined in 1023 (99.71%) and 3 (0.29%) of patients, respectively. According to the number of branches, LAA branching pattern of each patient was subclassifed in five morphological types. Based on the order and type-specific reference points, an anomalous LAA variants were classified into 20 subtypes. Type 1 (Typical branching pattern) LAA was identifed in 781 (76.12%) of the patients. Among 242 aberrant LAA variants (four types, 23.58%), the most common subtypes; Type 2A with brachiocephalico-carotid trunk (BCT), Type 4A₁ with an aberrant left vertebral artery (ALVA), and Type 3A₁, in which BCT coexisted with ALVA, were observed in 17.6%, 3.6%, and 0.88% of the cases, respectively. The frequency of remaining LAA variants ranged from 0.39% to 0.097%. In addition, Type 3B₂ and Type 4C were first identified in our study. We observed Type I and II RAA in one female (0.097%) and two cases (male and female, 0.19%), respectively. Knowledge of AA branching variations is of great interest in neck and thoracic surgery and the new morphological types in clinically applicable form recommended in this study can be used in endovascular interventions.

Retroesophageal right subclavian artery associated with a bicarotid trunk and an ectopic origin of vertebral arteries

A rare branching pattern of the aortic arch in a female cadaver is reported. An aberrant right subclavian artery originated from the distal part of the aortic arch and following a retroesophageal course was recognized. Next to it, from the left to the right, the left subclavian artery and a short bicarotid trunk originating the left and the right common carotid artery were recognized. An unusual origin of the vertebral arteries was also identified. The left vertebral artery originated directly from the aortic arch, whereas the right vertebral artery originated directly from the right common carotid artery. Retroesophageal right subclavian artery associated with a bicarotid trunk and ectopic origin of vertebral arteries represents an exceptional and noteworthy case.