Magnetic resonance angiographic evaluation of circle of Willis: A morphologic study in a tertiary hospital set up

Naveen, Shankar Rao; Bhat, Venkatraman; Karthik, Gadabanahalli Ashok

doi:10.4103/0972-2327.165453

Cited by 20 publications

(7 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This configuration was seen in 69.8% (n=37) and 90.2% (n=37) of males and females, respectively. This finding is similar to studies done by Naveen SR et al and Dr. Arjun Bhaddur et al which showed type A variant being the most common anterior circulation variant [27, 28].…”

Section: Discussionsupporting

confidence: 92%

Proportion of Variant Anatomy of the Circle of Willis and Association with Vascular Anomalies on Cerebral CT Angiography

Machasio

Nyabanda

Mutala

2019

Radiology Research and Practice

View full text Add to dashboard Cite

Background and Purpose. There is a wide variation in the anatomy of the CW in different individuals and population groups. The purpose of this study was to determine the proportion of variant anatomy of the circle of Willis (CW) and associated anomalies in patients with suspected cerebrovascular disease referred for cerebral computed tomography angiography (CTA) in two tertiary hospitals in Kenya. Methodology. This was a cross-sectional descriptive study conducted on 94 patients referred for cerebral CTA at the Kenyatta and Nairobi hospitals from August 2017 to February 2018. MIP and 3D reformatted images were analyzed by two senior radiologists to determine the final configuration of the CW and presence of vascular pathology. Vessels with diameters <0.8 mm were considered to be absent or hypoplastic. Chen et al. classification was used to determine the final configuration of CW. Results. Complete CW was seen in 37.2% (37.7% vs. 36.6% in males and females, respectively, p=0.909). Type A variant was the commonest anterior variant at 78.7%. Type E variant was the dominant posterior variant at 41.5%. Fetal PCA was demonstrated in 25.5%, unilateral > bilateral fetal PCA. Aneurysms were seen in 24.5% of patients. ACoA aneurysms were commonest at 43.6%. AVMs were seen in 8.5% of patients. Azygous ACA, fenestration, and duplication of vessels and persistent TA were not demonstrated. There is no significant association between aneurysms/AVMs and CW configuration. Conclusion. The findings in this study demonstrate slight differences in the CW configuration. A higher proportion of complete anterior CW was seen in female patients. Type A anterior and type E posterior circulation variants were the commonest in both males and females. No significant association was demonstrated between CW configuration and occurrence of aneurysms/AVMs in this study. Various methods of classification of CW configuration have been proposed with no standardized method to date, thus the need for consensus building between neuroanatomists, neurologists, neurosurgeons, and neuroradiologists for ease of comparison between similar future studies on the CW.

show abstract

Section: Discussionsupporting

confidence: 92%

Proportion of Variant Anatomy of the Circle of Willis and Association with Vascular Anomalies on Cerebral CT Angiography

Machasio

Nyabanda

Mutala

2019

Radiology Research and Practice

View full text Add to dashboard Cite

show abstract

“…Our results are similar with findings of Jalali Kondori et al [9] 5.7% and 0.95%, Chen et al [1] 5.92% with 1.38%. Duplication of ACoA occurred in 0.6%, or 3 patients, 0.3% in female and 0.9% in men, comparing with similar results of 0.95% [9] or 0.6% [14]. When an intracranial aneurysm ruptures, it causes subarachnoid haemorrhage.…”

Section: B C Asupporting

confidence: 52%

Anatomical variations and dimensions of arteries in the anterior part of the circle of Willis

et al. 2019

View full text Add to dashboard Cite

Background: The aim of this study was to investigate different anatomic variations and dimensions of anterior part of the circle of Willis (CW) and their prevalence on Kosovo's population. Materials and methods: This is an observational descriptive and retrospective study performed at the University Clinical Centre, Clinic of Radiology. The three-dimensional time-of-flight technique was used for magnetic resonance angiography imaging to evaluate the anatomy of the CW in 513 adults without clinical manifestations for cerebrovascular disease. The diameters of arteries of the CW were measured and variations were recorded. Results: The complete anterior part of CW was found in 64.3% of cases, more evident in female at about 66% than male 62.2%. Morphologic variations of the ACA1 are agenesis or hypoplasia in 5.65%, fusion of the anterior cerebral arteries (ACAs) on a short distance in 6.5% and fusion of the ACA on a long distance in 2.5%, median ACA is presented in 11 examined patients or 2.1%. Normal anterior communicating artery (ACoA) was seen in 68.2%, hypoplasia or absence 15.66%, double ACoA in 0.6% and fenestrations in 3.89%. The mean calibrations of the vessels were measured as 2.04 mm in right A1, 2.06 mm in left A1 and 1.16 mm of ACoA. While, 14.1 mm length of right A1, 13.87 mm of left A1 and 2.99 mm of ACoA. Conclusions: Knowledge of the variations and diameter of the anterior part of the CW has a great importance in determination of anatomical variations and diameter in general populations, also, in interventional radiology for various endovascular interventions as well as during anatomy lessons.

show abstract

“…15,16 Moreover, in 8% to 13% of patients both ACAs are supplied by only one internal carotid artery (ICA) due to an absent or hypoplastic A1 segment of the circle of Willis (CoW). [17][18][19] When monitoring is restricted to assessing frontal lobe perfusion, even widespread cerebral perfusion changes due to problems with the other carotid artery can remain undetected. 16 In a previous study, we have already shown that using multichannel continuous-wave near-infrared spectroscopy (CW-NIRS) to evaluate the effectiveness of collateral circulation might serve as an objective and early predictive marker of critical perfusion during percutaneous transluminal angioplasty or balloon occlusion testing of an ICA.…”

Section: Introductionmentioning

confidence: 99%

Spatially extended versus frontal cerebral near-infrared spectroscopy during cardiac surgery: a case series identifying potential advantages

et al. 2018

View full text Add to dashboard Cite

Stroke due to hypoperfusion or emboli is a devastating adverse event of cardiac surgery, but early detection and treatment could protect patients from an unfavorable postoperative course. Hypoperfusion and emboli can be detected with transcranial Doppler of the middle cerebral artery (MCA). The measured blood flow velocity correlates with cerebral oxygenation determined clinically by near-infrared spectroscopy (NIRS) of the frontal cortex. We tested the potential advantage of a spatially extended NIRS in detecting critical events in three cardiac surgery patients with a whole-head fiber holder of the FOIRE-3000 continuous-wave NIRS system. Principle components analysis was performed to differentiate between global and localized hypoperfusion or ischemic territories of the middle and anterior cerebral arteries. In one patient, we detected a critical hypoperfusion of the right MCA, which was not apparent in the frontal channels but was accompanied by intra- and postoperative neurological correlates of ischemia. We conclude that spatially extended NIRS of temporal and parietal vascular territories could improve the detection of critically low cerebral perfusion. Even in severe hemispheric stroke, NIRS of the frontal lobe may remain normal because the anterior cerebral artery can be supplied by the contralateral side directly or via the anterior communicating artery.

show abstract

Magnetic resonance angiographic evaluation of circle of Willis: A morphologic study in a tertiary hospital set up

Cited by 20 publications

References 28 publications

Proportion of Variant Anatomy of the Circle of Willis and Association with Vascular Anomalies on Cerebral CT Angiography

Proportion of Variant Anatomy of the Circle of Willis and Association with Vascular Anomalies on Cerebral CT Angiography

Anatomical variations and dimensions of arteries in the anterior part of the circle of Willis

Spatially extended versus frontal cerebral near-infrared spectroscopy during cardiac surgery: a case series identifying potential advantages

Contact Info

Product

Resources

About