Carotid-vertebral Anastomosis Research Articles

The Rostral Epidural Rete Mirabile: Functional Significance in Blood Flow Regulatory Mechanisms in Giraffe (Giraffa camelopardalis)

The distinctive long neck of the giraffe (Giraffa camelopardalis) entails functional difficulties brought about by the extended distance between the heart and the head. Blood must be circulated over 2 m from the heart to the brain against gravitational force. The natural movement of the head to ground level would result in a large volume of blood moving toward the brain with the force of gravity. Large blood volumes also rush to the brain during bulls’ fighting (necking), rendering the giraffe susceptible to possible brain damage. The natural movement of the head from ground level to fully erect would result in blood moving away from the brain with gravitational force. The lack of blood perfusing the brain can cause fainting. The giraffe, however, suffers neither brain damage nor fainting. What adaptations do giraffes have to counteract these challenges? The aim of this study was to investigate the functionality of the rostral epidural rete mirabile situated just beneath the brain and its possible contribution to successful circulation in long-necked giraffes. The unique rostral epidural rete mirabile structure significantly contributes to counteract physiological challenges. Turns and bends characterize this structural arterial meshwork and subsequently an increased artery length through which blood flow must proceed before entrance into the brain, exerting resistance to blood racing to the brain when the head is lowered to the ground. The brain is supplied mainly by the maxillary artery through the carotid rete, with a rudimentary basilar artery not contributing to the brain’s blood supply. The resistance to blood flow due to the structure and position of the rostral epidural rete mirabile when the head is in the upright position is counteracted by the unique carotid-vertebral anastomosis allowing immediate cerebral blood supply. The rostral epidural rete mirabile structure in giraffes is an essential feature balancing physiological difficulties arising due to the extensive heart-to-head distance and might fulfill the same function in other long-necked artiodactyls.

Mechanical Thrombectomy in Basilar Artery Stroke Attributable to Persistent Primitive Proatlantal Intersegmental Artery: A Case Report

Objective This clinical note describes a patient who presented with acute basilar artery occlusion and a persistent primitive proatlantal artery. Case Presentation We present the case of an 82‐year‐old woman who presented with sudden onset of left‐sided weakness. Cross‐sectional imaging revealed occlusion of the basilar artery with a persistent primitive proatlantal artery. She then underwent successful mechanical thrombectomy. Complete reperfusion was achieved; thereafter, she recovered well from the ischemic stroke and was discharged home. Discharge modified Rankin Scale score was <2. Conclusion This is the first case report of mechanical thrombectomy in a patient with persistent primitive proatlantal artery. Embryonic carotid vertebral anastomosis rarely persists in adult patients. Prompt and accurate recognition of these persistent embryonic anastomoses is of paramount importance in interpreting cross‐sectional imaging and planning revascularization procedures.

Persistent Trigeminal Artery: A Novel Imaging Finding in CHARGE Syndrome.

Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth and/or development, Genital and/or urinary abnormalities, Ear abnormalities and deafness (CHARGE) syndrome is an autosomal dominant genetic disorder with evolving clinical diagnostic criteria. Recently, a number of additional anomalies have been described in this syndrome, which may aid in early diagnosis, particularly in incomplete phenotypes or atypical cases. The persistent trigeminal artery is an embryonic carotid-vertebral anastomosis, rarely seen in the healthy population, with a reported prevalence of 0.4%. Because we had observed the persistent trigeminal artery in patients with CHARGE syndrome, this study aimed to explore the prevalence of the persistent trigeminal artery in this syndrome. A retrospective study was performed at our tertiary center. MR imaging studies, clinical records, and genetic results were reviewed for patients diagnosed with CHARGE syndrome between 2006 and 2019. The prevalence of the persistent trigeminal artery in patients with CHARGE syndrome was recorded and compared with other established diagnostic criteria. Twenty-five patients with CHARGE syndrome were included. The persistent trigeminal artery was demonstrated on MR imaging in 14/25 (56%) patients and was seen more frequently than 4 of 9 other established diagnostic criteria in our cohort. When individual major or minor diagnostic criteria were absent, the persistent trigeminal artery was still demonstrated on MR imaging in 52%-67% of these patients with CHARGE syndrome. The prevalence of the persistent trigeminal artery in CHARGE syndrome of 56% is higher than that of some other established diagnostic criteria and much higher than that in the general population. The persistent trigeminal artery may be a useful addition to the expanding phenotype of CHARGE syndrome, supplementing other diagnostic criteria. Radiologists should be aware of this novel finding demonstrable on MR imaging.

椎骨動脈狭窄と頚動脈椎骨動脈吻合を伴う内頚動脈狭窄症の1手術例

椎骨動脈狭窄と頚動脈椎骨動脈吻合を伴う内頚動脈狭窄症の1手術例

Proatlantal intersegmental artery: a review of normal and pathological features

Primitive carotid-vertebral and carotid-basilar anastomoses are formed early during human embryogenesis at approximately 24 days. From cephalic to caudal direction, these anastomoses are cranial extensions of the primitive internal carotid, trigeminal, otic, hypoglossal and proatlantal intersegmental arteries. Normal and/or abnormal morphofunctional aspects of prenatal and postnatal forms of the proatlantal intersegmental artery, from the 24th day of gestation to postnatal eight decades, are described according to personal and literature data. Many (ab) normal carotid-vertebral anastomoses are also marked in differential diagnosis of the proatlantal intersegmental artery. The proatlantal intersegmental artery maintains the posterior circulation until the vertebral arteries are fully developed between the seventh and eighth gestational weeks. When this artery fails to obliterate, it becomes persistent one. The proatlantal intersegmental artery, most commonly, is an incidental finding or it may be of clinical significance in some patients.

Persistent carotid-vertebral anastomosis associated with contralateral accessory middle cerebral artery

An exceptional case is reported of a complex anomaly of the brain arteries including low left carotid bifurcation, persistent carotid-vertebral anastomosis on the left and accessory middle cerebral artery on the right; the whole posterior circulation was only filled through the anomalous anastomotic vessel which joined with the vertebral artery because of a contralateral hypoplasic vertebral artery and the absence of both posterior communicating arteries. This association has not been previously reported in the literature. The embryological processes leading to these arterial anomalies are discussed. Risks related to a severe carotid stenosis or occlusion and to surgical or endovascular procedures in patients harboring these arterial anomalies are emphasized.

Cerebral Arteriovenous Malformation Embolized through Persistent Primitive Hypoglossal Artery

Carotid-vertebral anastomoses are commonly detected as incidental findings. But sometimes these channels are important for the clinical condition of the patient. Here a case of right thalamo- capsular arteriovenous malformation is described where a persistent primitive hypoglossal artery was the only route for embolization of the arteriovenous malformation.

Carotid endarterectomy in rare bilateral carotid-vertebral anastomosis

In the embryo, the anterior and the posterior cerebral circulations are connected by several longitudinal anastomotic vessels. These anastomoses aisappear progressively, until the carotid and vertebrobasilar systems are connected only by a pair of posterior communicating arteries. These embryonal anastomoses rarely persist in adults and may have an important physiologic role during carotid surgery. We report a case in which a patient with bilateral embryonal carotid-vertebral anastomoses underwent right carotid endarterectomy for asymptomatic internal carotid stenosis. (J Vasc Surg 2001;33:1122-4.)

Primitive persistent carotid-basilar and carotid-vertebral anastomoses: a report of seven cases and a review of the literature.

The persistence of embryonic carotid-basilar and carotid-vertebral anastomoses was investigated retrospectively in 4,400 cerebral angiograms. Six primitive persistent carotid-basilar anastomoses and one primitive persistent carotid-vertebral anastomosis were found. In 4,400 cerebral angiograms, the incidence of primitive carotid-basilar and carotid-vertebral anastomoses was 0.14% and 0.023% respectively. Primitive persistent anastomoses are associated with intracranial vascular anomalies, especially aneurysms. The clinical and pathological findings in combination with these primitive persistent anastomoses were also examined.

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A case of persistent carotid-vertebral anastomosis with occlusion of the right internal carotid artery is reported. This 68-year-old man was admitted to our hospital with left hemiparesis. Physical examination findings on admission were within normal range except for the hemiparesis and his blood pressure was 114 over 70mmHg. Right carotid angiogram revealed an occlusion of the right internal carotid artery and an abnormal vessel connecting the right external carotid artery and right vertebral artery. The vertebral arteries were hypoplastic bilaterally. Thereafter, the patient was transferred to the rehabilitation center and spent 134 days in the hospital. This “abnormal vessel” arises from the right occipital artery which branches from the right external carotid artery at the level between the 2nd and the 3rd vertebrae. It then curves slightly superiorly and joins the third portion of the right vertebral artery. This anastomotic vessel was thought to be “proatlantal artery II” in accordance with Lasjaunias et al. or a “persistent primitive first cervical intersegmental artery” in accordance with Padget. To our knowledge, this is only the 19th case of persistent carotid-vertebral anastomosis reported in the literature.

Proatlantal Intersegmental Artery associated with Hypertensive Intracerebral Hemorrhage

A 57-year-old male was hospitalized with stroke on the day of onset. An initial computed tomography revealed a hemorrhage in the left caudate nucleus. Common carotid angiography demonstrated a carotid-vertebral anastomosis. Complete selective external carotid angiography disclosed the proatlantal intersegmental and occipital arteries arising from the external carotid artery at the level of the atlas. The proatlantal intersegmental artery, which is one type of persistent primitive carotid-vertebrobasilar anastomosis, is rarely associated with hypertensive intracerebral hemorrhage, according to the literature.

Structural organization of the vertebral artery in the giraffe (Giraffa camelopardalis).

Vertebral arteries in the giraffe were removed and their structural organization was studied with light microscopy. It has been shown that the caudal segment of the vertebral artery extending to the level of the seventh cervical vertebra has a largely elastic structure, while the cranial segment has a muscular structure. The transition of the arterial wall normally occurs between the seventh and fifth cervical vertebral levels, and involves diminution of elastic tissue in the luminal portion of the tunica media and simultaneous increase of the smooth muscle content. The smooth muscle cells in the cranial portion show a clustered arrangement consisting of several smooth muscle fibres. The individual clusters are separated by connective tissue septa from which finer strands extend to surround individual muscle fibres. It is suggested that the vertebral and carotid arteries though found in the neck have a different structural organization, which, in turn, may imply that the two blood vessels are subjected to different haemodynamic demands. The findings of this study therefore render further support to the statement that the largely muscular structure of the common carotid artery in the giraffe may be related to the unique cerebral haemodynamics of this animal, rather than being a common feature of the blood vessels situated in the neck. A corollary to this suggestion is the fact that, in the giraffe, as in most other Artiodactyls, the vertebral blood does not participate in the supply of cephalic structures because it is confined to the cervical region by the pressure barrier in the carotid-vertebral anastomosis.

Ascending Pharyngeal vertebral Anastomosis with Bilateral Absence of Vertebral Arteries

The authors encountered a patient with an anomalous external carotid-vertebral anastomosis, which was found incidentally during examination for a recurrent pituitary adenoma. Left carotid angiography demonstrated a muscular branch of the ascending pharyngeal artery feeding the left vertebral artery, while bilateral retrograde vertebral angiography failed to demonstrate the origins of either vertebral artery. To our knowledge, this is the first documented case of ascending pharyngealvertebral anastomosis associated with the bilateral absence of vertebral arteries at their origins.

Congenital anomalies of the carotid arteries. Including the carotid‐basilar and carotid‐vertebral anastomoses. An angiographic study and a review of the literature. T. A. Lie. Excerpta Med. Found., Amsterdam. 143 pp. 1968

TeratologyVolume 2, Issue 3 p. 247-247 Book Review Congenital anomalies of the carotid arteries. Including the carotid-basilar and carotid-vertebral anastomoses. An angiographic study and a review of the literature. T. A. Lie. Excerpta Med. Found., Amsterdam. 143 pp. 1968 Robert L. McLaurin, Robert L. McLaurin Division of Neurosurgery, Cincinnati General Hospital, Cincinnati, OhioSearch for more papers by this author Robert L. McLaurin, Robert L. McLaurin Division of Neurosurgery, Cincinnati General Hospital, Cincinnati, OhioSearch for more papers by this author First published: August 1969 https://doi.org/10.1002/tera.1420020309Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume2, Issue3August 1969Pages 247-247 RelatedInformation

Congenital Anomalies of the Carotid Arteries, I ncluding the Carotid Basilar and Carotid Vertebral Anastomoses: An Angiographic Study and Review of the LiteratureCongenital Anomalies of the Carotid Arteries, I ncluding the Carotid Basilar and Carotid Vertebral Anastomoses: An Angiographic Study and Review of the Literature. By Lie T. A.. Cloth, $10.00. Pp. 154. Amsterdam, Excerpta Med. Found., 1968.

HomeRadiologyVol. 93, No. 1 PreviousNext Book ReviewsCongenital Anomalies of the Carotid Arteries, I ncluding the Carotid Basilar and Carotid Vertebral Anastomoses: An Angiographic Study and Review of the LiteratureMannie M. SchechterMannie M. SchechterMannie M. SchechterPublished Online:Jul 1 1969https://doi.org/10.1148/23.1.50MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In Article HistoryPublished in print: July 1969 FiguresReferencesRelatedDetailsRecommended Articles RSNA Education Exhibits RSNA Case Collection Vol. 93, No. 1 Metrics Altmetric Score PDF download

Congenital Anomalies of the Carotid Arteries, Including the Carotid-Basilar and Carotid-Vertebral Anastomoses: An Angiographic Study and a Review of the Literature

Anyone interested in cerebral and cervical arteriography would benefit from reading and studying this book. In addition to presenting common and uncommon anomalies of the carotid and vertebral arteries, the author has used embryology extensively to explain and understand how these interesting variations come about. The three primitive anastomoses (trigeminal, otic, and hypoglossal) between carotid and basilar arteries are described, but, in addition, the less-well-known suboccipital (proatlantal) and cervical intersegmental anastomoses are illustrated. The numerous connections between internal and external carotid arteries made prominent after occlusive disease of the internal carotid are well described and their relationship to embryological structures pointed out. They are illustrated by ordinary angiograms, subtraction films, stereoscopic films, and diagrams. The references (up to April 1967) are well chosen. The description of the wonderful net of arteries which connect internal and external carotid arteries in animals lays the groundwork for understanding the rare human cases included

Congenital external carotid-vertebral anastomosis. A case report.

A case is reported with a single large external carotid-vertebral anastomosis which was demonstrated by carotid angiography.The various reasons for development of such a channel are discussed.The presence of a large single channel, the direct course and lack of branching, and the lack of previous neurologic symptoms indicate that this particular vessel represents a congenital maldevelopment of the vascular supply to the brain.

Anomalous carotid-vertebral anastomosis: primitive cervical segmental artery

The authors describe a case of anomalous carotid-vertebral anastomosis as an occasional finding in angiographie examination. They believe this vessel could represent a “primitive cervical segmental artery”. As the shape and form of this artery may be similar to the primitive hypoglossal artery, the authors point out the peculiarities which allow a differentiation between the two primitive arteries. In the case described they found the following neuroradiological signs: