ArticlePloS one2020
Variations in the Circle of Willis in a large population sample using 3D TOF angiography: The Tromsø Study.
Article in PloS one, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers, 2 of them syntheses that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
28 citing papers in PubMed, 2 syntheses or guidelines pooled it, 60 citations in OpenAlex.
- A new classification system for the anatomical variations of the human circle of Willis: A systematic review.Journal of anatomy · 2022Pooled it
- Anatomical variations in the Circle of Willis and the formation and rupture of intracranial aneurysms: A systematic review and meta-analysis.Frontiers in neurology · 2022Pooled it
- Posterior communicating artery variation is linked to compromised cerebral hemodynamics in middle-aged and older adults.Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism · 2026Article
- Atypical variants of the cerebral arterial circle beyond the Lazorthes classification: a retrospective morphologic and neuroradiologic study.Surgical and radiologic anatomy : SRA · 2026Article
- The effect of distal aspiration catheter position on collateral flow in mechanical thrombectomy - anInterventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences · 2026Article
- Preoperative computed tomography perfusion and angiography predict the need for shunting in carotid endarterectomy: a multicenter study.Quantitative imaging in medicine and surgery · 2026Article
- Computational fluid dynamics assessment of altered hemodynamics in the Circle of Willis during acute ischemic stroke and the impact of cerebral collateral development.Biomechanics and modeling in mechanobiology · 2026Article
- A Historic Review of the Three-Century Journey of the Circulus Arteriosus Cerebri: Then and Now.Cureus · 2025Review
- Patterns of Circle of Willis Variants among Patients Undergoing 3 Tesla Magnetic Resonance Angiography at a Tertiary Care Hospital: An Observational Study.JNMA; journal of the Nepal Medical Association · 2025Observational
- Dissecting the Circle of Willis-Migraine connection: A review.AIMS neuroscience · 2025Review
- Preventing Embolization to a New Vascular Territory: An in Vitro Study Exploring Alternative Techniques for Dual-Stent-Retriever Cerebral Thrombectomy.Journal of neuroendovascular therapy · 2025Article
- Human cerebral blood supply via circulus arteriosus cerebri: A scoping review on its variations and clinical implications.Heliyon · 2024Article
- Non-Invasive Tools in Perioperative Stroke Risk Assessment for Asymptomatic Carotid Artery Stenosis with a Focus on the Circle of Willis.Journal of clinical medicine · 2024Review
- Exploring the anatomical configurations of the cerebral arteries in a cohort of South African patients.Scientific reports · 2024Article
- Magnetic resonance angiography in assessment of anomalies of anterior cerebral artery in adults.Anatomy & cell biology · 2023Article
- High resolution simulation of basilar artery infarct and flow within the circle of Willis.Scientific reports · 2023Article
- The Presence of Communicating Arteries in the Circle of Willis Is Associated with Higher Rate of Functional Recovery after Anterior Circulation Ischemic Stroke.Biomedicines · 2023Article
- Association between Anatomical Variations of the Circle of Willis and Covert Vascular Brain Injury in the General Population.Cerebrovascular diseases (Basel, Switzerland) · 2023Article
- Reclassifications of ischemic stroke patterns due to variants of the Circle of Willis.International journal of stroke : official journal of the International Stroke Society · 2022Article
- Total arch replacement with the frozen elephant trunk technique for a right-sided aortic arch with a Kommerell diverticulum and aberrant right vertebral artery.Interactive cardiovascular and thoracic surgery · 2022Article
Corrections and comments
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Authors and funding
6 authors at 4 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The main arteries that supply blood to the brain originate from the Circle of Willis (CoW). The CoW exhibits considerable anatomical variations which may have clinical importance, but the variability is insufficiently characterised in the general population. We assessed the anatomical variability of CoW variants in a community-dwelling sample (N = 1,864, 874 men, mean age = 65.4, range 40-87 years), and independent and conditional frequencies of the CoW's artery segments. CoW segments were classified as present or missing/hypoplastic (w/1mm diameter threshold) on 3T time-of-flight magnetic resonance angiography images. We also examined whether age and sex were associated with CoW variants. We identified 47 unique CoW variants, of which five variants constituted 68.5% of the sample. The complete variant was found in 11.9% of the subjects, and the most common variant (27.8%) was missing both posterior communicating arteries. Conditional frequencies showed patterns of interdependence across most missing segments in the CoW. CoW variants were associated with mean-split age (P = .0147), and there was a trend showing more missing segments with increasing age. We found no association with sex (P = .0526). Our population study demonstrated age as associated with CoW variants, suggesting reduced collateral capacity with older age.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.