Anastomosis, EC-IC

In this article, we gathered cases with interesting external carotid-internal carotid anastomoses.



DSA - Right ICA Injection (PA [Top] and Lateral [Bottom])

The right middle meningeal artery (red arrows) is arising from the right ophthalmic artery (blue arrow), as observed during an injection into the right ICA. By the way, did you notice the aneurysm?

2 Occipital-Vertebral Anastomosis


DSA - Left ECA Injection (PA [Left] and Lateral [Right])

On this left ECA angiogram, an anastomosis (blue arrow) can be seen between the left occipital artery (red arrow) and the left VA (green arrow).


On this ECA angiogram, an anastomosis (blue arrow) can be seen between the occipital artery (red arrow) and the VA (green arrow).


Right ICA Injection

This patient presented with stroke activation, and the right internal carotid artery run showed a right M1 occlusion (yellow arrow). Interestingly, an anastomosis was also observed between the right ophthalmic artery (red arrow) and the right middle meningeal artery (green arrow). Subsequent mechanical thrombectomy achieved a TICI 2C reperfusion (inset images).

(A): PA view.
(B): Lateral view.
Blue arrow: Anterior branch of the MMA.
Orange arrow: Posterior branch of the MMA.


This patient presented with a ruptured paraophthalmic aneurysm that necessitated urgent coiling. Subsequently, a flow diverter embolization was carried out in a delayed manner. Notably, there existed an ophthalmic artery origin stenosis (A, red arrow), showcasing normal flow (B). However, following the deployment of the flow diverter, a hindrance in the flow (C and D, yellow arrow) was observed. An external carotid artery injection (E) revealed a choroidal blush (F, green arrow), signifying an EC-ophthalmic artery anastomosis.