Vertebral artery dissection caused by atlantoaxial dislocation in a patient with Marfan syndrome.

A small number of case reports have documented a link between atlantoaxial dislocation (AAD) and vertebral artery dissection (VAD), but this association has never been described in patients with hereditary connective tissue disorders. We present a case of an 18-year-old female patient, diagnosed with Marfan syndrome since the age of one, who underwent brain MRA for intracranial aneurysm screening revealing tortuosity of the internal carotid and vertebral arteries as well as atlantoaxial dislocation. Since the patient was asymptomatic, a wait-and-see approach was chosen, but a follow-up MRA after 18 months showed the appearance of a dissecting pseudoaneurysm of the V3 segment of the left vertebral artery. Despite the patient being still asymptomatic, it was decided to proceed with C1-C2 stabilization to prevent further vascular complications. Follow-up imaging showed realignment of the atlantoaxial joint and reduction of the dissecting pseudoaneurysm of the left vertebral artery. In our patient, screening MRA has led to the discovery of asymptomatic arterial and skeletal abnormalities which, if left untreated, might have led to severe cerebrovascular complications. Therefore, AAD correction or close monitoring with MRA should be provided to MFS patients with this craniovertebral junction anomaly, even if asymptomatic.

Cervical anterior spinal artery infarction associated with anomalous vertebral artery: a case report.

We report a unique case of cervical anterior spinal artery (ASA) infarction in a 49-year-old male with hypercholesterolemia and sleep apnea. The patient experienced sudden cervical pain, quadriparesis, areflexia, and urinary incontinence after swallowing a large food bolus. Imaging revealed an infarction at the C3-C5 levels and an anomalous right vertebral artery (VA) originating from the thoracic aorta, tightly enclosed between the aorta and a vertebral column with an anterior osteophyte. This aberrant VA was the primary vascular supply to the ASA, with no contribution from the left VA or supreme intercostal arteries. We propose that transient injury to the right VA, induced by compression between the aortic arch, the food bolus, and the osteophyte, led to temporary hypoperfusion of the ASA, causing a watershed ischemic injury in the mid cervical cord's anterior gray matter. The article also provides an in-depth discussion of the developmental and clinical characteristics associated with this rare vascular anomaly.

Anatomy of vertebral artery hypoplasia and its relationship with clinical implications: a systematic review and meta-analysis of prevalence.

PURPOSE: The vertebral artery (VA) is a vital branch of the subclavian artery, coursing through the transverse foramina of the cervical vertebrae, and playing a crucial role in irrigating the posterior region of the arterial cerebral circle, also known as the Polygon of Willis. Among the various possible alterations that can affect the VA, vertebral artery hypoplasia (HAV) emerges as a significant variant. This study aims to discern the anatomical features of HAV and its correlation with the clinical conditions of the posterior cerebral circulation. METHODS: The databases Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS were searched until January 2024. Two authors independently performed the search, study selection, and data extraction. Methodological quality was evaluated with an assurance tool for anatomical studies (AQUA). Pooled prevalence was estimated using a random effects model. RESULTS: A total of 24 studies met the established selection criteria, with a total of 8847 subjects. In this study, 6 articles were included for the meta-analysis with a total of subjects. The average prevalence of VAH reported in each study was 11% (95% CI 10-12%); the studies had a heterogeneity of 41% based on the funnel plot and a low risk of bias. CONCLUSION: The prevalence of VAH is low, but in the presence of this condition, the changes are mainly in diameter rather than morphological. If it is present, some clinical safeguards must be taken to avoid complications such as stroke.

[Persistent Primitive Arteries].

Primitive anastomotic arteries temporarily exist between the future internal carotid and vertebrobasilar arteries during the early embryonic period(between 28 and 32 days of life). The primitive trigeminal, otic, hypoglossal, and proatlantal intersegmental arteries serve as major blood channels to the developing vertebrobasilar circulation at this stage. These arteries are replaced by the posterior communicating and vertebral arteries, and the primitive anastomotic arteries rapidly regress following the development of the definitive vertebrobasilar circulation. Occasionally, these primitive anastomoses persist and are incidentally discovered after birth. Physicians who treat cerebrovascular diseases should be familiar with the anatomy and functions of these vessels. In this review, we discuss the embryonic basis of the carotid-vertebrobasilar anastomoses and the clinical significance of their persistent forms in adults.

[Anatomical Variations to the Vertebral Artery and Posterior Inferior Cerebellar Artery are Associated with the Partial Persistence of Primitive Lateral Basirovertebral Anastomosis].

The angioarchitecture of the hindbrain is homologous to that of the spinal cord, and its vascular system can be analyzed at the longitudinal and axial structures. During embryonic development, there are two main longitudinal arteries: the longitudinal neural artery and the primitive lateral basilovertebral anastomosis. Commonly observed variations are formed by the fenestration and duplication of either the vertebrobasilar artery, or cerebellar artery, which can be observed when the primitive lateral basilovertebral anastomosis partially persists. Understanding the pattern and development of blood supply to the hindbrain provides useful information of various anomalies in the vertebrobasilar junction and cerebellar arteries.

A comprehensive analysis and literature review of vertebral artery variation in craniovertebral junction using three-dimensional computed tomography angiography.

PURPOSE: To describe vertebral artery (VA) variation in patients with or without osseous anomalies at congenital craniovertebral junction (CVJ). METHODS: In the present study, we retrospectively analyzed 258 patients with VA variation who underwent three-dimensional computed tomography angiography (3D CTA) in our hospital from March 2017 to October 2019. RESULTS: Among 258 patients, 180 were accompanied by skeleton structural malformation, including 105 cases of occipital ossification of the atlas, 8 cases of the bipartite atlas, 7 cases of hypoplasia of the posterior arch of the atlas, 45 cases of C2/3 congenital fusion, 2 cases of C2/3/4 congenital fusion, and 13 cases of congenital os odontoid. VA variation was divided into type A (VA variation in the CVJ area without osseous anomalies) and type B (VA variation in the CVJ area with osseous anomalies). There are totally 10 subtypes, including type A1 (atlas occipitalization with VA entrance approach close to middle line, 20.2%); type A2 (atlas occipitalization with VA entrance approach far from middle line, 30.2%); type A3 (first intersegmental VA in C1-C2, 1.9%); type A4 (fenestration of the VA, 2.3%); type A5 (VA bulging type, 6.6%); type A6 (VA exposures with the absence of the posterior atlas arch, 2.3%); type A7 (C2 inner wall type, 0.4%); type A8 (single vertebral artery, 2.3%); type B1 (posterior ponticuli, 2.7%); and type B2 (high-riding VA, 31.4%). CONCLUSION: This study is expected to take the lead in the most comprehensive classification of VA variation.

Rotational vertebral artery occlusion in a patient with basilar invagination.

Basilar invagination (BI) is a congenital or acquired craniovertebral junction (CVJ) anomaly with odontoid process superiorly migrating into the foramen magnum. Compression of neural structures is the most relevant complication of BI. However BI is also a rare cause of ischemic stroke. In this case we reported a 30-year-old female with BI who developed recurrent ischemic stroke in posterior circulation. Before the onset of ischemic stroke, she didn't present neck pain or clinical signs of lower cranial nerve dysfunction, brainstem compression or transient ischemic attack. At first she suffered from sudden onset of left-sided hemidysesthesia. Magnetic resonance imaging from a local hospital revealed an acute infarction in the right thalamus. Cerebral MR angiography was unremarkable at that time. The tip of the odontoid process had protruded into the foramen magnum and could be observed at the level of the lower medulla, but unfortunately it was ignored by the clinicians and the radiologists. She was given antiplatelet therapy and the sensory disturbance disappeared gradually. However she experienced a recurrence in the pontine and midbrain region 2 months later. At this time she was transferred to our hospital, and reconstructed computed tomography of cervical spine demonstrated basilar invagination, atlanto-axial dislocation, and atlanto-occipital assimilation. Computed tomographic angiography (CTA) revealed a dominant right vertebral artery (VA) and a redundant loop in its third segment. Dynamic cerebral angiogram demonstrated that the patient had a Bow Hunter's type phenomenon, with dynamic occlusion of the right dominant VA during contralateral head turn. This case highlighted the necessary of hemodynamic evaluation in asymptomatic basilar invagination.

A rare adult case of asymptomatic double aortic arch accompanied by the right vertebral artery directly originating from the aortic arch.

INTRODUCTION: A double aortic arch (DAA) is a rare congenital vascular anomaly. No case of DAA with a direct aortic origin of the right vertebral artery (VA) has been reported in adults. Here, we report a rare case of an asymptomatic DAA accompanied by the right VA directly originating from the right aortic arch in an adult. CASE PRESENTATION: A DAA and right VA directly originating from the right aortic arch were identified in a 63-year-old man using digital subtraction angiography and computed tomography angiography. The patient underwent digital subtraction angiography for evaluation of an unruptured cerebral aneurysm. Intraprocedural selection of vessels branching from the aorta with the catheter was difficult. To confirm the bifurcation of the aorta, aortography was performed, which revealed a DAA. Following digital subtraction angiography, computed tomography angiography was performed, which showed that the right VA originated directly from the right aortic arch. The trachea and esophagus were located in the vascular ring of the DAA; however, they were not compressed by the aorta. This was consistent with the lack of symptoms related to the DAA. CONCLUSIONS: This is the first adult case of an asymptomatic DAA with an unusual origin of the VA. A rare asymptomatic vascular anomaly, such as a DAA, can be incidentally identified using angiography.

Morphometric evaluation of cerebellar lobules in individuals with unilateral vertebral artery hypoplasia.

PURPOSE: Vertebral arteries (VAs) provide blood circulation to the posterior fossa in general and are the main blood supply of the posterior fossa structures of the brain. Our aim in this study is to analyze the segmental volumetric values of cerebellar structures with the voxel-based volumetric analysis system in individuals with unilateral vertebral artery hypoplasia. METHODS: In this retrospective study, segmental volumetric values/percentile ratios of cerebellar lobules were calculated using 3D fast spoiled gradient recall acquisition in steady-state (3D T1 FSPGR) MRI sequence images of the brain in individuals with unilateral vertebral artery hypoplasia (VAH) and in those without bilateral VAH and any symptoms of vertebrobasilar insufficiency as the control group was evaluated in volBrain ( http://volbrain.upv.es/ ). RESULTS: The VAH group consisted of 50 (19 males/31 females) and the control group had 50 (21 males/29 females) individuals. The cerebellar lobule III, IV, VIIIA and X total volumes and the cerebellar lobule I-II, III, IV, VIIIA and X gray matter volumes were lower in the hypoplastic side than the non-hypoplastic cases and also than the contralateral side of the hypoplastic cases in the VAH group. In addition, it was found that that lobules IV and V had lower cortical thickness and lobules I-II had a higher coverage rate in the intracranial cavity in the hypoplastic side than the non-hypoplastic cases and also than the contralateral side of the hypoplastic cases (p < 0.05). CONCLUSION: In this study, it was found that cerebellar lobule III, IV, VIIIA, X total volumes and cerebellar lobule I-II, III, IV, VIIIA, X gray matter volumes in addition to lobule IV, V cortical thicknesses were low in individuals with unilateral VAH. Being aware of these variations and taking them into account during future volumetric studies on the cerebellum are very important.

Anterior artery release, distraction and fusion (ARDF) for radiculopathy caused by a vertebral artery loop.

BACKGROUND: Anomalous vertebral artery (VA) with loop formation is a rare cause of cervical nerve root compression. Various techniques with anterior and posterior approaches have been described for surgical treatment once conservative treatments fail. We herein present a case treated with the new technique of anterior release, distraction and fusion (ARDF) and further provide an updated review of surgically managed VA loops in the subaxial spine. CASE DESCRIPTION: A 76-year-old female complained of a 6-year history of pulsating, shooting pain in her right arm to the thumb. After obtaining repeated MRI, the VA loop compressing the right-sided C6-nerve root was detected. A neurovascular decompression through ARDF which led to an indirect loop straightening was performed. The patient immediately improved after surgery and remained pain-free 1 year postoperative. CONCLUSION: Neural irritation due to VA loop formation is a rare cause of cervical radiculopathy. While various surgical strategies have been described, we believe that anterior and anterolateral approaches are the safest to yield neurovascular decompression. We described and documented ARDF (anterior VA release, intervertebral distraction and fusion) on a patient case. LEVEL OF EVIDENCE: II (Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding).

Isolated atlas-duplication as a manifestation of persistent proatlas: a case report.

PURPOSE: Atlas-duplication is an exceedingly rare dysplasia of the craniocervical junction. To the best of our knowledge, only two cases of atlas-duplication have been reported and these were associated with complete anterior rachischisis and os odontoideum. We aimed to report a case of isolated atlas-duplication of incidental finding and without attributable symptoms which makes it unique. METHODS: Following a normal coronarography for a suspected myocardial infarction, a 60-year-old-man with no significant medical history developed a transient ischemic attack that justified brain computed-tomography angiography. RESULTS: There was no evidence for cerebral ischemic lesion, intracranial occlusion or significant artery disease. Bone analysis revealed eight cervical vertebral segments with an additional vertebral level located between the occiput and the atlas. This vertebra presented all the morphological characteristics of an atlas vertebra except for hypoplasia of the left transverse process. An incomplete anterior rachischisis was associated, and there was no other abnormality of craniocervical junction. The clinical examination revealed no neck pain, no limitation of joint amplitude and no neurological deficit. Apart from preventive treatment of ischemic stroke, no orthopedic or surgical treatment was undertaken. After 1.5 years of radiological monitoring, the patient remains symptom-free. CONCLUSIONS: Atlas-duplication is an exceedingly rare dysplasia of the craniocervical junction that may be found isolated and incidentally. If this variation does not necessarily warrant specific treatment, brain CT angiography is recommended to detect anatomical variations of the vertebral arteries.

Duplicated posterior inferior cerebellar arteries one of which was supplied by the jugular branch of the ascending pharyngeal artery.

PURPOSE: To describe a case of duplicated posterior inferior cerebellar arteries (PICAs), one of which was supplied by the jugular branch of the ascending pharyngeal artery (APA). CASE REPORT: A 62-year-old man with cerebral infarction underwent cranial magnetic resonance (MR) imaging and MR angiography. MR angiography showed a hyperplastic left APA, that was found to enter the posterior cranial fossa and continue to the PICA. Another left PICA arising from the V4 segment of the left vertebral artery (VA) and a tiny left anterior inferior cerebellar artery (AICA) were also identified. The source images of MR angiography revealed that the anomalous artery was passing through the medial side of the jugular foramen pars vascularis. The two left PICAs did not fuse to each other. DISCUSSION: There are four types of the PICA arising from the carotid system: (1) the PICA arises from the cavernous segment of the internal carotid artery (ICA) (persistent trigeminal artery variant); (2) the PICA arises from the cervical segment of the ICA (persistent hypoglossal artery variant); (3) the PICA arises from the APA via the hypoglossal canal; and (4) the PICA arises from the APA via the jugular foramen. Two PICAs sometimes arise from the V4 segment of the VA. In this common variation, the AICA is usually absent. This is the first reported case involving the association of (4) and a duplicated PICA with a tiny AICA. CONCLUSION: To identify this variation, careful observation of source images and creation of partial maximum-intensity-projection images of MR angiography are important.

Combined unusual origin and course of the right vertebral artery and right inferior thyroid artery: a case report.

PURPOSE: An unusual unilateral origin and course of the prevertebral part of the right vertebral artery and anomalous course of the right inferior thyroid artery was observed during dissection of the neck of a cadaver. METHODS: An accidental finding in the cadaver within the anatomical dissection was assessed. RESULTS: The right vertebral artery originated a nonstandard from brachiocephalic trunk and travelled in the anterior cervical region, along the longus colli muscle in front of the transverse processes from C7 to C4, and it entered the transverse foramen of C3. During its course, the position of the right inferior thyroid artery varied: it turned medially and passed posterior to the vertebral vessels and later curved inferomedially to its termination. Additionally, the left vertebral artery of the same cadaver arose directly from the subclavian artery and entered the transverse foramen at C6, and the left inferior thyroid artery passed anterior to the vertebral artery. CONCLUSION: Variation in the vertebral artery and inferior thyroid artery alone have been reported, but a combined variation is rare. The anatomical information from this study will be useful during dissection, angiography, endovascular surgery, thyroidectomy and non-invasive procedures in the cervical region.

Bilateral vertebral arteries arising distal to the left subclavian artery: embryological and anatomical description.

Abnormalities in the origin of vertebral arteries are relatively uncommon, but extremely rare when this abnormality happens on both sides. We present an anatomic variation in which both vertebral arteries came from the proximal descending thoracic aorta beyond the left subclavian artery with no other supra-aortic vessels accompanying the abnormality. The right vertebral artery took a retro-oesophageal course (lusoria artery), while the right and the left vertebral arteries enter the transverse foramina at the 7th cervical vertebra. From an embryological point of view, and overall controversial, this anomaly can be explained by the bilateral persistence of the 8th intersegmental artery as the origin of vertebral artery, instead of the dorsal segment of the 7th intersegmental artery being the origin, which is normally the case. The adequate identification of vertebral artery anomalies in complementary explorations is very important to avoid misdiagnosed vertebral occlusions or unexpected vertebral artery injuries during supra-aortic trunks, thyroid, and oesophagus open surgeries, among others, or even over the course of endovascular procedures.

Right vertebral artery arising from the right common carotid artery with an absent brachiocephalic trunk.

The right and left vertebral arteries are the first branches of the ipsilateral subclavian arteries. However, in the presence of anatomical variation due to complex embryogenesis, the vertebral artery can arise directly from the aortic arch or any of its major branches. The atypical origin of the vertebral artery is commonly associated with the left vertebral artery. Anatomical variation in the origin of the right vertebral artery is rare. Most available reports are case reports from international studies. We report on a case of right vertebral artery arising from the ipsilateral common carotid artery with an absent brachiocephalic trunk in a South African patient examined by digital subtraction angiography. Reports on anatomical variations are of diagnostic importance prior to surgical interventions or endovascular treatment of cerebrovascular diseases such as cerebral aneurysms and arteriovenous malformations.

Aberrant right subclavian artery with right type 1 proatlantal artery and segmental dysplasia of the right internal carotid artery: a case report.

PURPOSE: We present a case of an aberrant right subclavian artery (ARSA) with extremely rare vascular anomalies. CASE REPORT: A 69-year-old woman was suspected to have right internal carotid artery (ICA) stenosis. Computed tomography angiography demonstrated an ARSA and hypoplasia of the right ICA. The proximal segment of the right vertebral artery (VA) was aplasia, and a right type 1 proatlantal artery (PA) arose from the right common carotid artery. Cerebral angiography demonstrated segmental dysplasia of the right ICA. The ascending intrapetrous segment and the ascending foramen lacerum-horizontal intracavernous segment of the right ICA demonstrated hypoplasia. The collateral pathways promoted reconstitution of each of the distal segments. Left internal carotid angiography demonstrated anterior communicating artery aneurysm and sufficient cross flow to the contralateral middle cerebral artery via the AcomA. DISCUSSION: A type 1 PA with an ARSA may result in the regression of the right dorsal aorta with persistence of the first cervical intersegmental artery. Although there are few findings of a relationship between an ARSA and intracranial artery anomalies, a developmental error of the right dorsal aorta may cause such complex vascular anomalies. CONCLUSION: Knowledge of anatomical variations in patients with ARSA is useful when performing angiography or endovascular therapy, as well as during clinical follow-up.

Association of Vertebral Artery Hypoplasia and Vertebrobasilar Cerebrovascular Accident.

Background and Objectives: Vertebral artery hypoplasia (VAH) is a controversial risk factor for cerebral infarction. The aim of this study was to analyze the prevalence of vertebral artery hypoplasia and to evaluate its association with vertebrobasilar cerebrovascular accidents. Materials and Methods: The study was conducted in the Neurology Departments of the Republican Vilnius University Hospital from 2015 to 2020. Data of 742 subjects (133 patients with posterior circulation infarction or vertebral artery syndrome (PCI/VAS), 80 patients with anterior circulation infarction (ACI) and 529 control subjects with no symptoms of cerebrovascular accident) were analyzed. Ultrasound examination of the extracranial internal carotid and vertebral arteries (VA) was performed, risk factors were recorded. Results: The mean age of the subjects was 64.51 ± 13.02 years. In subjects with PCI/VAS the diameter of VA was smaller, and the prevalence of VAH was higher compared to those in subjects with ACI and in the control group. A higher degree of VAH in subjects younger than 65 years of age increased the risk of PCI/VAS. Subjects with non-dominant VA diameter of 2.7-2.9 mm had 2.21 times higher risk of PCI/VAS, subjects with non-dominant VA diameter of 2.5-2.6 mm had 2.36 times higher risk of PCI/VAS, and subjects with non-dominant VA diameter of 2.2-2.4 mm had 4.12 times higher risk of PCI/VAS compared with subjects with non-dominant VA diameter of ≥3 mm. Among patients with PCI/VAS those with VAH had lower rates of ischemic heart disease compared with patients with normal VA diameter. There was no difference in the rates of other risk factors between PCI/VAS patients with and without VAH. Conclusions: Vertebral artery hypoplasia is not a rare finding in individuals without symptoms of cerebrovascular accident, but more frequent in patients with vertebrobasilar cerebral infarction or vertebrobasilar artery syndrome. Vertebral artery hypoplasia can be considered a risk factor for posterior circulation infarction in subjects under 65 years of age.

New diagnostic algorithm for detection of covert Bow Hunter's Syndrome.

Bow hunter's syndrome (BHS) should not be overlooked as a cause of cerebral infarction in the posterior circulation. However, covert BHS, which does not impair blood flow with simple rotation but only at certain angles, may make the diagnosis of BHS difficult. We propose a new algorithm to detect BHS or covert BHS. We recommend that BHS and covert BHS be detected by noninvasive duplex ultrasonography, which will allow for appropriate treatment.

Asymmetry of P1 and vertebral arteries is not related to basilar tip aneurysm development or rupture.

OBJECTIVE: Lately, morphological parameters of the surrounding vasculature aside from aneurysm size, specific for the aneurysm location, e.g., posterior cerebral artery angle for basilar artery tip aneurysms, could be identified to correlate with the risk of rupture. We examined further image-based morphological parameters of the aneurysm surrounding vasculature that could correlate with the growth or the risk of rupture of basilar artery tip aneurysms. METHODS: Data from 83 patients with basilar tip aneurysms (27 not ruptured; 56 ruptured) and 100 control patients were assessed (50 without aneurysms and 50 with aneurysms of the anterior circle of Willis). Anatomical parameters of the aneurysms were assessed and analyzed, as well as of the surrounding vasculature, namely the asymmetry of P1 and the vertebral arteries. RESULTS: Patients with basilar tip aneurysm showed no significant increase in P1 or vertebral artery asymmetry compared with the control patients or patients with aneurysms of the anterior circulation, neither was there a significant difference in asymmetry between cases with ruptured and unruptured aneurysms. Furthermore, we observed no significant correlations between P1 asymmetry and the aneurysm size or number of lobuli in the aneurysms. CONCLUSION: We observed no significant difference in aneurysm size, rupture, or lobulation associated with P1 or vertebral artery (surrounding vasculature) asymmetry. Therefore, the asymmetry of the surrounding vessels does not seem to be a promising morphological parameter for the evaluation of probability of rupture and growth in basilar tip aneurysms in future studies.

Non-Dolichoectatic Vertebral Artery Compression of the Medulla: A Comprehensive Literature Review.

OBJECTIVE: Vertebral artery compression of the medulla is a rare vascular finding that causes a variety of clinical presentations, from asymptomatic to neurological disability. This article presents the largest literature review to date on medullary compression of the vertebral arteries. METHODS: An English literature search was performed using the PubMed database and the keywords vertebral artery tortuosity, vertebral artery compression, and medullary compression. RESULTS: A comprehensive literature search yielded 68 patients (57% male) with medullary compression by an intracranial vertebral artery (ICVA). The left side of the medulla was compressed in 44, the right side in 19, and bilateral in 7. The most common clinical symptom was weakness - 26 patients (36%) - 6 had quadriparesis and 6 had hemiparesis. 21 patients reported imbalance; 12 various sensory symptoms; 4 patients were asymptomatic. CONCLUSIONS: Understanding the anatomy of the vasculature can help mitigate future debilitating stroke symptoms. Concrete guidelines for revascularization surgery in symptomatic patients may also be effective. Future studies are needed to further clarify the prevalence, natural history, vascular etiology, and treatment of this condition, including asymptomatic patients and the likelihood that they will develop further neurological signs and disability.