===== 🧬 Aneurysm Formation =====

Intracranial aneurysms are pathological dilations of the cerebral arterial wall, typically occurring at **arterial bifurcations** where **hemodynamic stress** is concentrated.

==== 🧠 Hemodynamic Contributors ====
Computational fluid dynamics (CFD) studies suggest that the following factors may contribute to aneurysm initiation:
  * **High wall shear stress (WSS)** → may damage endothelial cells
  * **Flow bifurcations** → increase mechanical stress on vessel walls
  * **Complex or unstable flow patterns** → lead to endothelial dysfunction
  * **Low WSS zones** → promote inflammation, wall remodeling and degeneration

==== 🧩 Biological Mechanisms ====
CFD findings are integrated with biological hypotheses:
  * **Endothelial injury** triggers inflammatory cascades
  * **Smooth muscle cell apoptosis** weakens wall structure
  * **Matrix degradation** via MMPs (matrix metalloproteinases)
  * **Genetic predisposition** may modulate vulnerability

==== 📌 Typical Locations ====
  * Anterior communicating artery (ACoA)
  * Posterior communicating artery (PCoA)
  * Middle cerebral artery (MCA) bifurcation
  * Internal carotid artery (ICA) siphon