Artery, Anterior Cerebral

The anterior cerebral artery is one of the two terminal branches of the internal carotid artery. It travels medially into the interhemispheric space, supplying the medial anterior part of the cerebra and other midline structures.



This patient presented with an acute left M1 occlusion. Without cross-filling of the contralateral ACA through the ACOM, this DSA presents a clear image of the left ACA and its branches (although not in the classic textbook manner).

  1. Ophthalmic artery
  2. MCA (occluded)
  3. Medial lenticulostriate arteries
  4. A1 (horizontal/pre-communicating segment)
  5. A common branch of 6 and 7
  6. Orbitofrontal artery
  7. Frontopolar artery
  8. A2 (vertical/post-communicating/infracallosal segment)
  9. Callosomarginal artery (somewhat small)
  10. Anteromedial frontal branches
  11. A3 (precallosal segment)
  12. Intermediomedial frontal branches
  13. Posteromedial frontal and paracentral branches
  14. A4 (supracallosal segment)
  15. A5 (postcallosal segment)
  16. Precuneal branches

2. A2 Trifurcation

This patient presented with a severe headache and diffuse SAH on CT head. 3D reconstruction from the CTA head showed a small ACOM aneurysm, a hypoplastic/atretic left A1, and an A2 trifurcation variation (A, B, and C). Figures (D) and (E) demonstrate standard DSA PA and lateral views. Figures (F) and (G) are zoomed-in post-coiling working angle views of the aneurysm.

3. Azygous ACA


This CTA shows an Azygous ACA with no ACOM. This anomaly is reported to be associated with saccular aneurysms.[1]


Here is a VRT image from a CTA head of another patient.

Blue arrow: azygous ACA.

4. Atresia

(A): The PA view of the right ICA injection reveals an atretic right A1 segment.
(B): The PA view of the left ICA injection demonstrates patent ACOM artery and cross-filling of the right ACA.
(C) and (D): The arterial and capillary phases of the lateral view of the right ICA injection depicted branches of the right MCA and their respective territories without ACA contamination.

  1. Saccular Aneurysm of the Azygos Anterior Cerebral Artery: Three Case Reports - PMC ↩︎