Pericallosal berry aneurysm associated with azygous anterior cerebral artery – a case report

Introduction. Azygos anterior cerebral artery is a rare variant of the anterior segment of the circle of Willis caused by an unusual fusion of the normally paired A2 segments of the anterior cerebral artery (ACA). Despite its rare occurrence, it is associated with various vascular and structural cerebral abnormalities, particularly berry aneurysms. Aim. We aimed to present a case of a 41-year-old female patient who presented to our neurology department with complaints of headache. Description of the case. She had a positive paternal history of aneurysmal subarachnoid hemorrhage. Magnetic resonance angiography (MRA) of her brain revealed an azygos ACA (bifurcating into two pericallosal arteries) which was associated with a saccular aneurysm at its bifurcation point. She was referred to the interventional radiology department for preventive endovascular treatment. Conclusion. Azygos ACA carries a high risk of aneurysm development and its occlusion can potentially compromise blood supply to both cerebral hemispheres. It is therefore crucial for clinicians to be aware of its significance and to report its presence in angiographic studies.

Azygous Anterior Cerebral Artery Acute Occlusion Managed With Endovascular Mechanical Thrombectomy: 2-Dimensional Operative Video

Mechanical thrombectomy has become the standard of care for management of most acute large-vessel occlusion (LVO) strokes. Most intracranial occlusions are located in the middle cerebral and internal carotid arteries. We present a unique case of acute occlusion of an azygous anterior cerebral artery (ACA). A 59-yr-old man with known hypertension and alcoholism presented with right hemiparesis, right facial palsy, aphasia, and dysarthria. His initial National Institutes of Health Stroke Scale (NIHSS) score was 20. Computed tomographic angiography and perfusion imaging demonstrated acute bilateral ACA occlusion with viable penumbra and preserved cerebral blood volume. The patient was not a candidate for intravenous tissue plasminogen activator because he presented with a wake-up stroke. After consent was obtained from his family, the patient was taken urgently for endovascular recanalization. Digital subtraction angiography confirmed acute azygous ACA occlusion. Under conscious sedation, the patient underwent mechanical thrombectomy with a stent retriever and a large-bore aspiration catheter. Successful revascularization (thrombolysis in cerebral infarction [TICI] grade 3) of the azygous ACA and both A2 arteries was obtained after 2 attempts and the use of a different stent retriever (first a 3 × 30 mm Trevo [Stryker Neurovascular, Kalamazoo, Michigan] and then a 4 × 40 mm Solitaire Platinum [Medtronic, Dublin, Ireland]). A reperfusion catheter was used during both attempts. No procedure-related complications occurred. The patient was discharged to a rehabilitation facility 3 d after the procedure with an NIHSS score of 2. In this video, we present the operative nuances of an uncommon location of LVO and its endovascular management.

In Situ Left Azygous Anterior Cerebral Artery to Right Pericallosal Artery Bypass for Treatment of a Giant Right A1/2 Aneurysm: 2-Dimensional Operative Video

Here we present a 46-yr-old man with recurrent syncopal episodes thought to be of cardiac origin. He was eventually found to harbor a giant, partially thrombosed, saccular aneurysm arising from the A1/A2 segment of the right anterior cerebral artery with foramen of Monro obstruction and a trapped left-sided ventricular system. An azygous left A2 artery segment supplied both callosomarginal arteries. We performed an in situ side-to-side anastomosis between the distal left azygous anterior cerebral artery and the right pericallosal artery, which was previously supplied by the right A1. The right A1 was clip ligated, and the aneurysm evacuated with an ultrasonic aspirator. Postoperatively, the patient did well with no recurrence of the aneurysm and resolution of his preoperative obstructive hydrocephalus. He continues to be independent >7 yr post surgery. His 6-mo follow-up angiogram revealed a patent bypass.

ARTERIA ÁCIGOS CEREBRAL ANTERIOR. REPORTE DE 2 CASOS Y REVISIÓN DE LA LITERATURA. Azygos anterior cerebral artery. Report of two cases and review of the literature

La arteria ácigos cerebral anterior (AACA) es un vaso formado por la fusión de ambas arterias pericallosas. Su presencia en series anatómicas es inferior al 5% de los casos. El objetivo de los autores es presentar dos casos de AACA asociados a un aneurisma intra-craneano y una malformación arteriovenosa (MAV). Casos clínicos: el caso 1 es una paciente de 52 años con un cuadro de hemorragia subaracnoidea. Una tomografía de cráneo (TC) confirmó el diagnóstico. Se hizo areriografía que evidenció un aneurisma de la AACA. El mismo fue clipado sin incidentes. El caso 2 se trata de un hombre que presentó un hematoma intraparenquimatoso y tenía antecedentes de haber sido operado por una malformación arteriovenosa (MAV). Una nueva arteriografía evidenció un remanente de MAV nutrido por ramos de una AACA. Se intervino sin complicaciones intraoperatorias, pero falleció en la evolución por una sepsis. La AACA es un vaso que se ve de forma transicional en embriones humanos y que se encuentra de forma reglada en mamiferos inferiors. Su presencia en cerebros adultos humanos e poco frecuente. Se destaca su asociación con aneurismas intracraneanos y alteraciones del desarrollo de la línea media cerebral. The azygos anterior cerebral artery (AACA) is a vessel formed by the fusion of both pericallosal arteries. Its presence in anatomical series is less than 5%. We present two cases of AACA, one associated with an aneurysm and other associated to an arteriovenous malformation (AVM). Clinical cases: Case 1 is a 52-year-old woman who was admitted to a hospital with sudden onset of sensory depression and headache. A cranial axial tomography (CT) demonstrated a sub-arachnoid hemorrhage. Cerebral angiography showed an aneurysm of an azygous anterior cerebral artery bifurcation. Surgical clipping was carried out with an excellent outcome. The second case is a 71-year-old man that had been operated 20 years before, of a right frontal AVM. He was admitted to a medical center with an acute severe left hemiparesis. The CT showed a right sided frontal haematoma and the cerebral angiography showed an AVM, partly fed by an AACA. The malformation was surgically treated, but the patient died at a later time as a consequence of sepsis. The AACA is seen as a transitional vessel in the human brain embryologic development, and is found in some inferior mammals and monkeys. This artery is seen in early stages related to the development of the corpus callosum. However, it disappears later on in most of the cases. Its existence in adults is infrequent, but has been reported in isolated cases sometimes associated with vascular malformations as those presented.

Bihemispheric Posterior Inferior Cerebellar Artery Occurring with an Azygos Anterior Cerebral Artery: Case Study

Variations in intracranial vasculature are well known. We report a rare anatomic variation in a patient who underwent cerebral angiography for suspected intracranial aneurysm. Digital subtraction angiography revealed a bihemispheric posterior inferior cerebellar artery (PICA) and an azygous anterior cerebral artery (ACA). There was no evidence of any aneurysm or vascular abnormality. To our knowledge, this is the first reported case of a patient with a common PICA supplying both the cerebellar hemispheres and a common ACA supplying ACA territory bilaterally. It is important for the physician to be aware of these anatomical variations in order to differentiate a normal variant from a pathological condition.