| ECAA classification |
| Type I: Isolated aneurysms of the internal carotid artery |
| Type II: Aneurysms of the complete internal carotid artery with involvement of the bifurcation |
| Type III: Aneurysms of the carotid bifurcation |
| Type IV: Combined aneurysm of the internal and common carotid artery |
| Type V: Isolated aneurysm of the common carotid artery |