Proatlantal Artery Research Articles

Disappearing Cerebral Communicating Vessels in Embryonic Development—With a Case of Carotid-Vertebrobasilar Artery Anastomosis

In early embryonic development, anastomoses between carotid and basilar arteries occur in the primitive trigeminal, primitive otic, primitive hypoglossal, and primitive proatlantal arteries, and these anastomoses gradually disappear as the embryo continues to develop. This article reported a case of vascular anastomosis occurring between the external carotid artery and vertebral artery.

An unusual anatomical variant: A transclival artery supplying the vertebrobasilar circulation.

The persistent carotid-vertebrobasilar anastomoses are arterial communications between the anterior and posterior circulations due to the persistence of embryological connections. We here present an extremely rare instance of a transclival persistent carotid-vertebrobasilar anastomosis in a 10-month-old infant, which does not fit into any of the traditionally described categories, such as the trigeminal artery, hypoglossal artery, or proatlantal artery.

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.

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

We present a case of an aberrant right subclavian artery (ARSA) with extremely rare vascular anomalies. 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 ascendingforamen 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. 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. Knowledge of anatomical variations in patients with ARSA is useful when performing angiography or endovascular therapy, as well as during clinical follow-up.

Huge Fenestration of the Vertebral Artery and Fenestrated Basilar Artery.

Background: Fenestrations, such as those of the vertebral artery (VA), are generally regarded as arterial slits. To the authors’ knowledge, large fenestrations of the VA were reported twice previously, those morphological patterns being different. We hereby report a third pattern of such large fenestration of the VA. Methods: It was found serendipitously on the computed tomography angiograms of a 63 year-old male which were documented retrospectively. Results: The findings were as follows: Conclusions: Large fenestrations of the VA could result if, during embryogenesis, the proximal segment of the lateral basivertebral anastomosis and the distal segment of the proatlantal artery persist. Large fenestrations of the VA bring into a narrow neurosurgical field an additional arterial trunk that should be carefully documented preoperatively in order to avoid hemorrhagic events.

Features of the cerebellar vascular supply (review)

Ischemic and hemorrhagic strokes remain the most devastating diseases of cerebrovascular system. They may cause disorders of speech, memory, mental health or movement. However, stroke can be prevented. Knowledge of the vascularization of the cerebellum and its variations is important for choosing a strategy of prevention and effective treatment of stroke. This review will discuss the variant anatomy of three pairs of cerebellar arteries: superior cerebellar artery (SCA), anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA). In most cases SCA and AICA arise from basilar artery, PICA arises from vertebral artery. SCA supplies tentorial cerebellar surface and dentate nucleus, AICA – petrosal surface of the cerebellum, flocculus, tegmentum, pons and middle cerebellar peduncles, PICA – suboccipital surface of the cerebellum, tonsil, inferior vermis, fastigial nucleus, choroid plexus and medulla. We conclude that SCA is the most constant artery and PICA is the most variable one. SCA can originate from the junction of the first segment of posterior cerebral artery and basilar artery or directly from the first segment of posterior cerebral artery. AICA can arise from vertebral artery or from common trunk with PICA. Rarely AICA arise from PICA. PICA can originate from basilar artery, extradural part of vertebral artery (C1-C2 or even C2-C3), ascending pharyngeal artery, proatlantal artery, ascending cervical artery or rarely from internal carotid artery. Many analyzed studies showed that PICA can be absent more often than AICA; SCA is almost always present. SCA is also duplicated more than other cerebellar arteries (mostly on the left). Significant difference was found in different studies about frequency of duplication of the AICA. PICA is rarely duplicated. Territories of cerebellar arteries change depending on their origin, course and also on the absence or duplication of the other ones. Many studies showed that SCA, AICA or PICA can dominate and send their branches to the territories of the other arteries which are absent or hypoplastic. The present study also describes classifications of segments of the cerebellar arteries, types of cerebellar vascular supply and superficial vascular network. Keywords: human, cerebellum, superior cerebellar artery, anterior inferior cerebellar artery, posterior inferior cerebellar artery.

Is a trident or a bident? Appearance of a primitive trigeminal artery on sagittal views

•Recognition of a persistent primitive trigeminal artery (PPTA) is of clinical significance due to its association with aneurysms and several vascular variants in addition to preoperative planning.•Characteristic appearance of PPTA on MR sagittal images of the brain resembles the Greek letter tau (two prongs) and was linked to Neptune’s trident (three prongs).•Use of a bident sign as a more visually and mythologically precise description of the appearance of PPTA. A 50 year old male with an incidental finding on the MRI brain (Fig. 1).Fig. 2A) Lateral digitally subtracted catheter angiogram of a selected internal carotid artery (arrow) injection demonstrating the persistent trigeminal artery (arrowhead) passing posteriorly to join the basilar artery (open arrow). B) Cropped view of the painting “Concilio degli dei” by Raffaello Sanzio da Urbino depicting Hades holding a bident (left), next to his brother Poseidon holding a trident (middle) [10]. Zeus (right) is also pictured, without a spear.View Large Image Figure ViewerDownload Hi-res image Download (PPT) A.fetal posterior cerebral arteryB.persistent trigeminal arteryC.persistent hypoglossal arteryD.persistent otic arteryE.persistent proatlantal artery Answer on page 240 Is a trident or a bident? Appearance of a primitive trigeminal artery on sagittal viewsJournal of Clinical NeuroscienceVol. 75PreviewA persistent primitive trigeminal artery (PPTA) is the remnant of the embryonic arterial circulation in adults and is the most common type of the persistent carotid-vertebrobasilar anastomoses (with frequency 0.1–0.6%); followed by persistent hypoglossal artery (0.02–0.1%), persistent proatlantal artery and otic artery, which existence, however, remains controversial [6,7]. A PPTA arises from the proximal cavernous part of the ICA and courses posteriorly to join the basilar artery. Recognition of a PPTA is of clinical significance due to its association with aneurysms and several vascular variants [1,4]. Full-Text PDF Erratum to “Is a trident or a bident? Appearance of a primitive trigeminal artery on sagittal views – Question and Is a trident or a bident? Appearance of a primitive trigeminal artery on sagittal views – Answer” [J. Clin. Neurosci. 75C (2020) 204–205 and 240–241]Journal of Clinical NeuroscienceVol. 78PreviewThe publisher regrets to inform readers that there was an error in the article title for both the question and answer articles. The correct title is ‘Is it a trident or a bident? Appearance of a persistent primitive trigeminal artery on sagittal views – Question’ and ‘Is it a trident or a bident? Appearance of a persistent primitive trigeminal artery on sagittal views – Answer’ respectively. Full-Text PDF

Carotid-vertebrobasilar anastomosis: magnetic resonance and computed tomographic angiographic demonstration.

Carotid-vertebrobasilar (VB) anastomoses are rare and usually found incidentally, but they can have clinical significance. Their variance can represent aneurysm formation at the origin of the anomalous artery, cerebral ischemia due to unique blood flow, or other complications. Thus, recognition and correct diagnosis of these anomalous vessels are important when interpreting magnetic resonance (MR) and computed tomography (CT) angiography. This pictorial essay presents MR and CT angiographic images of several types of persistent fetal carotid-VB anastomoses, including those involving the proatlantal, hypoglossal, and trigeminal arteries as well as their variants. Images depict types 1 and 2 proatlantal arteries, persistent second cervical intersegmental artery, persistent hypoglossal artery (PHA), PHA of external carotid origin, two types of the PHA variant, posterior inferior cerebellar artery arising from the jugular branch of the ascending pharyngeal artery, lateral and medial types of persistent trigeminal arteries (PTAs), and four types of PTA variants.

Persistent carotid-vertebrobasilar anastomoses: cases of proatlantal artery Type I and Type II

Persistence of fetal communications between the carotid and vertebrobasilar systems is uncommon. Persistent proatlantal artery is an anastomosis between the carotid and vertebrobasilar systems, typically classified as Type I and II. In this case report, 600 angiographies are examined retrospectively and two persistent proatlantal arteries were observed - one with Type I (0.16%) and the other with Type II (0.16%) proatlantal artery. Existence of these arteries are associated with intracranial vascular anomalies, especially aneurysms. In both of our cases, an aneurysm was detected in the middle cerebral artery. Precise knowledge of these anastomoses is essential for intracranial operations and catheterizations performed in this region.

An anomalous adventure of type I proatlantal artery

An anomalous adventure of type I proatlantal artery

Diagnosis of variants of carotid-vertebasilar anastomoses on MR angiography

Objective To explore the feature of embryonic communication between the carotid and vertebro-basilar system using MRA of head and neck on MR. Methods The MRA images from 7 246 consecutive patients in Liaocheng People's hospital between June 2009 and December 2015 were retrospectively reviewed. The feature of embryonic communication between internal carotid, external carotid artery and vertebro-basilar system using MRA was analyzed by two doctors. Results Forty-four cases of embryonic communication between the carotid and vertebro-basilar system were found. Thirty-nine cases of primitive trigeminal artery (PTA) and primitive trigeminal artery variants (PTAV) were detected by MRA. The prevalence of both PTA and PTAV was 0.54% (PTA, 27 cases;PTAV, 12 cases). Twenty-three cases of PTA were lateral types;four cases were medial types. All PTA originated from C4 portion of internal carotid artery, of which 27 cases connected with the basilar artery and two cases connected with the superior cerebellar artery. The region of the BA proximal to the site of convergence with the PTA was hypoplastic in seven cases and completely absent in two cases. Three cases of primitive hypoglossal artery and 2 cases of primitive proatlantal artery were detected by MRA. The prevalence of primitive hypoglossal artery and primitive proatlantal artery was 0.04% and 0.03% respectively. Two cases of primitive hypoglossal artery were from the lateral internal carotid artery and one was from the external carotid artery. It's all on the right side. One case of primitive proatlantal artery was on the left which arises from the external carotid artery, one on the right which originated from the outer part of the internal carotid artery. Thirty-four cases were coexisted with other variants of head and neck vessels. All of the primitive hypoglossal arteries were coexisted with vertebral artery absence. One case of primitive proatlantal intersegmental artery was coexisted with vertebral artery dysplasia. Eighteen cases were associated with cerebral infarctions, and three cases with aneurysm. Conclusions MRA can accurately assess the variants of carotid-vertebasilar anastomoses and have diagnostic significance. Key words: Magnetic resonance imaging; Primitive trigeminal artery; Primitive hypoglossal artery; Primitive proatlantal intersegmental artery

Stent Placement for Stenosis at the Origin of a Persistent Primitive Proatlantal Artery: A Case Report

Stent Placement for Stenosis at the Origin of a Persistent Primitive Proatlantal Artery: A Case Report

The Role of the Primitive Lateral Basilovertebral Anastomosis of Padget in Variations of the Vertebrobasilar Arterial System.

The primitive lateral basilovertebral anastomosis (PLBA) is an embryonic longitudinal anastomotic channel that transiently interconnects the developing branches of the vertebrobasilar system. This study reviews the anatomy of the PLBA and describes several variants associated with its partial persistence. Four types of vertebrobasilar anomalies linked to the PLBA are illustrated by 13 angiographic observations. The angiographic appearances of (i) typical and atypical persistent trigeminal artery variants, (ii) common trunks of origin for one, two, or three cerebellar arteries, (iii) aberrant origins of the cerebellar arteries, and (iv) vertebrobasilar duplications are described. The PLBA is the cranial continuation of the ascending ramus of the dorsal radicular branch of the proatlantal artery (i.e., the radicular artery of C1) and represents the cranial equivalent of the posterior-lateral spinal artery. Several previously ill-defined or misunderstood variations of the vertebrobasilar system can be explained by partial persistence of the PLBA. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:2025-2038, 2017. © 2017 Wiley Periodicals, Inc.

Extracranial internal carotid artery: anatomical variations in asymptomatic patients

The anatomical variations of internal carotid artery (ICA) are mostly asymptomatic, thus being disregarded and only incidentally diagnosed, with very few symptomatic patients. The awareness of these anomalies is crucial to solve the differential with other neck lesions, preventing accidental injuries during neck surgery. Therefore, the aim of our study is to estimate the prevalence of ICA anomalies, using magnetic resonance angiography (MRA) and computed tomography angiography (CTA). 253 patients underwent head and neck MRA and CTA examinations, with multiplanar and volumetric reformations. For each set of images, the following items were investigated: origin, development, course, persistence of embryonic vessels and anomalous origin of collateral branches. In our series, ICA arose from the bifurcation of the common carotid artery at the level of: C4 in 303 hemi-necks (59.9%); C3 in 98 hemi-necks (19.3%); C5 in 57 hemi-necks (11.3%); C2 in 48 hemi-necks (9.5%). ICA kinking and/or coiling was found in 105 hemi-necks, and location variation of ICA (reversed-type) in two hemi-necks. In just one case the origin of the ascending pharyngeal artery was from ICA (0.2%), while an anomalous persistence of the proatlantal artery was noticed in three cases (0.6%). CTA and MRA showed similar accuracy in detecting ICA anomalies.

The supreme intercostal artery includes the last cervical intersegmental artery (C7) ‐ angiographic validation of the intersegmental nomenclature proposed by Dorcas Padget in 1954

In 1954, Dorcas Padget wrote a note that settled the debate over the labeling of the intersegmental arteries (ISAs) and the level of origin of the subclavian artery (SubA), in agreement with earlier observations made by Hochstetter in the rabbit (1890) and Schmeidel in man (1932). In her proposed nomenclature, Padget introduced the name of proatlantal artery and confirmed that the SubA was associated with the sixth ISA rather than the seventh. However, a generally unnoticed consequence of this now widely accepted terminology lays in its incompatibility with the traditional view of the costocervical trunk (CT), regarding in particular the anatomy of the supreme intercostal artery (SIA). If the SubA derives from the sixth cervical ISA (ISA 6), and the CT provides the first and second posterior IAs (ISA 8 and 9), the seventh cervical ISA (ISA 7) then remains unaccounted for. The purpose of this study was to examine Padget's nomenclature in the light of modern angiographic material to identify the missing seventh ISA. Our findings validate the terminology used by Padget, including the addition of a pro-atlantal artery and the identification of the ISA most commonly associated with the SubA as the sixth ISA, but they also emphasize the need to redefine the anatomy of the SIA to incorporate the seventh cervical ISA.

Preserved distal flow in a proximally occluded internal carotid artery due to a persistent proatlantal artery

Preserved distal flow in a proximally occluded internal carotid artery due to a persistent proatlantal artery

Persistent primitive proatlantal artery の狭窄病変に対してステント留置術を行い plaque shift を生じた1 例

【目的】進行性脳梗塞を呈したpersistent primitive proatlantal artery（PPPA）の起始部狭窄病変に対してステント留置術を行い，術後plaque shift による内頚動脈狭窄を生じた症例を経験したため報告する．【症例】71 歳男性．一過性左片麻痺で受診．内科的加療中，進行性脳梗塞を認めた．DSA にて狭窄を伴ったPPPA を認め，動脈原性塞栓が病態の原因と考えられた．ステント留置術を施行し，良好な拡張を得たが内頚動脈にplaque shift を来してしまった．【結論】脳血管内治療ではplaque shift は稀な現象であるが，分岐部狭窄病変にステントを留置する際には術前のプラーク局在評価も重要になると考えられた．

Artère proatlantale de type II avec origine atypique d’une artère occipitale alimentant une fistule artérioveineuse durale de type IV : cas clinique

Case reportWe report the case of a 49 year-old woman, who presented with an intracranial haemorrhage. During cerebral angiography investigations, we observed an unusual vertebral artery that originated from the external carotid artery and an uncommon origin of the occipital artery from the vertebral artery feeding a dural arteriovenous fistula grade IV. This rare vertebral artery origin is probably the remnant of a type II proatlantal artery. In addition, the origin of the occipital artery evoked a vascular development disease including a dural arteriovenous fistula which may be the result. These multiple vascular abnormalities could be explained by embryologic disorders.

Monolateral type I proatlantal artery with bilateral absence of vertebral arteries: description of a case and review of the literature

We report a case of a patient with right type I proatlantal intersegmental artery associated with right fetal posterior cerebral artery and absence of both vertebral arteries and of the left posterior communicating artery. We also describe the clinical relevance of these findings for this patient. A 56-year-old woman with vertigo and tinnitus underwent contrast enhanced Magnetic Resonance Angiography (MRA) of the supra-aortic arteries using a 1.5 Tesla scanner. Maximum intensity projection and volume rendering reconstructions were obtained. MRA demonstrated the persistence of an anastomotic artery between the right internal carotid artery and basilar artery, passing through the foramen magnum, suggesting a type I proatlantal intersegmental artery. The examination also showed the absence of both vertebral arteries and the presence of a right fetal-type posterior cerebral artery. To our knowledge, this is the first report of a type I proatlantal intersegmental artery associated with an omolateral fetal-type posterior cerebral artery and the absence of both vertebral arteries and of the left posterior communicating artery. This condition requires a watchful monitoring of the patient and has to be considered in case of surgical procedures of the carotid arteries.

Persistent Bilateral Proatlantal Type Ii Artery

Vascular anomalies and variants are common in patients undergoing imaging studies, and patients with these anomalies are generally asymptomatic. Remnants of fetal carotid-basilar circulation are rarely identified. We report a rare case of persistent type 2 bilateral proatlantal arteries, in which the patient presented with dizziness.