The network of arteries supplying blood flow to the brain is more likely to be incomplete in people who suffer migraine, a new study by researchers in the Perelman School of Medicine at the University of Pennsylvania reports. Variations in arterial anatomy lead to asymmetries in cerebral blood flow that might contribute to the process triggering migraines.
The image depicts the anatomy of the circle of Willis (A) and representative subjects with a complete (B) and incomplete circle of Willis (C). The arrowhead indicates absent anterior communicating artery and arrows indicate bilateral absent posterior communicating arteries.
Abbreviations are defined as ICA: internal carotid artery; ACA: anterior cerebral artery; MCA: middle cerebral artery; PCA; posterior cerebral artery; BA: basilar artery; VA: vertebral artery; Acomm: anterior communicating artery; Pcomm: posterior communicating artery; A1, A2, P1, P2: branches of the anterior and posterior cerebral arteries. The vertebral arteries are not normally considered part of the circle of Willis, but are important to the intracranial arterial supply.