Variations in the Circle of Willis in a large population sample using 3D TOF angiography: The Tromsø Study
Fig 5
Heatmap of conditional probabilities that Y-artery is missing given that X-artery was missing.
Numerators and denominators of conditional probability estimates are provided in the brackets, and represent respectively the number of times two segments are missing at the same time (joint probability) and per column the number of times the artery X is missing (independent probability). The common denominator of the joint probabilities and independent probabilities have cancelled. ACA: Anterior cerebral artery. ACoA: Anterior communicating artery. PCoA: Posterior communicating artery. PCA: Posterior cerebral artery. Left and right lateralization are denoted by “L” and “R” respectively. Each successive heatmap interval increases in size with 0.05.