Normal Variants of the Circle of Willis in patients undergoing CT Angiography

Prasad, Vinay; Chhetri, Pradip; Paudel, Asmita

doi:10.3126/jcmsn.v13i1.16659

Cited by 6 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Aplasia and hypoplasia were the most common ACoA variants with 24.1% ( n = 7) and 44.8% ( n = 13), respectively. This was similar to studies published by Prasad et al 6 and Shaikh and Sohail 9 who both recorded the ACoA as most anomalous in the anterior circulation.…”

Section: Discussionsupporting

confidence: 91%

“…The frequency of a complete CoW varies between populations ranging from 22.2% in an adult Pakistani population 9 to 46.7% in an Egyptian population. 8 Other frequencies obtained were 24.28% in a northeastern Indian population, 5 35.4% in a Nepalese population, 6 34.50% in a Nigerian population, 17 and 69.57% in a Malawian population. 18 Our sample, which comprised predominantly East Indians (54.9%) showed a complete CoW in 24.3% and an incomplete/partial CoW in 75.7%.…”

Section: Discussionmentioning

confidence: 85%

“…CoW anomalies described include aplasia, hypoplasia, and accessory vessels. 2–4 The most common variant as described by Saikia et al 5 and Prasad et al 6 was PCoA hypoplasia in 20% and 26.2%, respectively, followed by foetal origin of the PCA in 13.8%, where the P1 segment of the PCA was smaller than the ipsilateral PCoA.…”

Section: Introductionmentioning

confidence: 96%

See 2 more Smart Citations

Anatomical variations in the circle of Willis on magnetic resonance angiography in a south Trinidad population

Diljohn,

Rampersad,

Maharaj

et al. 2023

BJR|Open

View full text Add to dashboard Cite

Objectives This article seeks to determine the prevalence of a complete circle of Willis (CoW) and its common morphological variations in a south Trinidad population, while also investigating the influence of gender, age, and ethnicity on CoW morphology. Methods A prospective, descriptive, cross-sectional study was done on the magnetic resonance images for consecutive patients who had a brain MRI/magnetic resonance angiography at a tertiary health institution in south Trinidad between October 2019 and September 2020. Patients with significant cerebrovascular disease and/or a history of prior neurosurgical intervention were excluded. Results A complete CoW was seen in 24.3%, with more complete circles observed in younger participants (≤45 years) and Afro-Trinidadians. No gender predilection for a complete CoW was demonstrated. The most common variations in the anterior and posterior parts of the circle were a hypoplastic anterior communicating artery (8.6%, n = 13) and bilateral aplastic posterior communicating arteries (18.4%, n = 28), respectively. Conclusions Significant variations exist in the CoW of a south Trinidad population with a frequency of complete in 24.3%, and more complete circles in younger patients and Afro-Trinidadians. Gender did not influence CoW morphology. Advances in knowledge Structural abnormalities in the CoW may be linked to future incidence of cerebrovascular diseases and should therefore be communicated to the referring physician in the written radiology report. Knowledge of variant anatomy and its frequency for a particular populations is also required by neurosurgeons and neuro-interventional radiologists to help with preprocedural planning and to minimize complications.

show abstract

Section: Discussionsupporting

confidence: 91%

Section: Discussionmentioning

confidence: 85%

See 1 more Smart Citation

Anatomical variations in the circle of Willis on magnetic resonance angiography in a south Trinidad population

Diljohn,

Rampersad,

Maharaj

et al. 2023

BJR|Open

View full text Add to dashboard Cite

show abstract

“…This is consistent with contemporary literature reports. 3 15 The mechanisms by which cerebral artery hypoplasia occurs are considered to be related to hemodynamic factors. In this case, the differential growth of the various parts of the brain will continuously change the hemodynamic demands and consequently the flow patterns in the cerebral arteries.…”

Section: Discussionmentioning

confidence: 99%

Cerebral Artery Hypoplasia in a Select Adult Kenyan Population

Ogeng’o

Cheruiyot

Amuti

et al. 2019

Journal of Neurosciences in Rural Practice

View full text Add to dashboard Cite

Background Hypoplasia of cerebral arteries predisposes to stroke and cerebral aneurysms which have an increased incidence in sub-Saharan Africa. The frequency and pattern of cerebral artery hypoplasia, however, shows population variations, and data from the African population remain scanty. Objectives This study aimed to determine the percentage of hypoplasia in the anterior, middle, and posterior cerebral, anterior and posterior communicating, basilar, and vertebral arteries. Materials and Methods Sections of the basilar, vertebral, posterior, and anterior communicating arteries and anterior, middle, and posterior cerebral arteries were taken, processed for histology, and examined with a light microscope at ×40. The images of the vessels were taken by a photomicroscope and circumference analyzed with the aid of Scion image analyzer. The average diameter of 10 sections was taken to be the diameter of the artery in analysis. Hypoplasia was then defined as internal diameter ≤1 mm. Photographs of representative samples of asymmetry were taken, data were analyzed using SPSS, and gender differences were analyzed using the Student's test. Results were presented in tables. Results Two hundred and eighteen formalin-fixed brains of adult Kenyans at the Department of Human Anatomy, University of Nairobi, were studied. Of the 218, 48 brains (22%) did not have vessels with any form of hypoplasia while 170 (78%) did have vessels. Of these, anterior circulation hypoplasia (anterior cerebral artery and posterior communicating artery) was seen in 100 brains (46%) and posterior circulation hypoplasia (middle and posterior cerebral, basilar, and vertebral arteries) in 69 brains (32%). Conclusion Cerebral arterial hypoplasia is frequent in the select adult Kenyan population.

show abstract

“…The posterior circulation is formed by the basilar artery, which branches to form right and left posterior cerebral arteries (PCA), supplying blood to the posterior part of the brain. The anterior and posterior circulations are connected to each other via a thin threadlike posterior communicating artery (PComA) which is a branch of ICA 9 .…”

Section: Introductionmentioning

confidence: 99%

Variation in Calibre of Arteries of Circle of Willis with Age: An MRA Based Study

Brohi¹,

Borges²,

Hassan³

et al. 2018

ashkmdc

View full text Add to dashboard Cite

Objective: To establish reference range for the diameters of arteries forming the Circle of Willis (CoW) and to correlate it with age. Methods: This cross-sectional study was conducted at the Radiology Department from January to July 2018. It comprises of patients referred for MR imaging of brain without any manifestation of cere- brovascular diseases. Patients who were claustrophobic or had a history of atherosclerosis, vasculi- tis, thrombus, aneurysm, arteriovenous malformation (AVM), intracranial tumour, diabetes and hypertension were excluded. 300 individuals comprising both males and females with mean age of 45 ± 11.6 (years) were recruited via non-probability sampling technique. Three-dimensional Time of Flight (TOF) Magnetic Resonance Angiography (MRA) was performed. Diameters of all component vessels forming the Circle of Willis were measured. Results: The diameter of the anterior cerebral, anterior communicating, internal carotid, posterior communicating, posterior cerebral and basilar arteries were found to be 1.51 ± 0.28 mm, 1.05 ± 0.37 mm, 3.69 ± 0.23 mm, 1.10 ± 0.11 mm, 1.85 ± 0.23 mm, 3.00 ± 0.11 mm respectively. Spearman correlation demonstrated that the diameters of the arteries were significantly correlated with age in different ways. Significant moderate positive correlations of internal carotid and basilar artery diameters were seen with age. Significant weak negative correlations were seen in anterior and posterior cerebral arteries. Significant very weak negative correlations were seen in anterior and posterior commu- nicating artery diameters and age. Conclusion: The normal reference values for vessels diameter of CoW were determined in general population living in Karachi. Diameter of the arteries showed statistically significant correlation with age in different ways. Knowledge of calibre of the arteries is helpful in cerebrovascular surgeries and radiological neuro interventions.

show abstract

Normal Variants of the Circle of Willis in patients undergoing CT Angiography

Cited by 6 publications

References 8 publications

Anatomical variations in the circle of Willis on magnetic resonance angiography in a south Trinidad population

Anatomical variations in the circle of Willis on magnetic resonance angiography in a south Trinidad population

Cerebral Artery Hypoplasia in a Select Adult Kenyan Population

Variation in Calibre of Arteries of Circle of Willis with Age: An MRA Based Study

Contact Info

Product

Resources

About