Posterior Cerebral Artery Aneurysms with Common Carotid Artery Occlusion: A Report of Two Cases

Abstract

Objective: Common carotid artery occlusion (CCAO) is much rarer than internal carotid artery occlusion (ICAO). Many cases of intracranial aneurysms due to hemodynamic stress caused by ICAO have been reported. On the other hand, only seven cases of intracranial ruptured aneurysms with CCAOs have been reported. We report the two patients with CCAOs and unruptured posterior cerebral artery (PCA) aneurysms.

Case Presentations: The two patients presented CCAOs and unruptured PCA aneurysms. Digital subtraction angiography (DSA) showed that these patients had collateral circulation from the ipsilateral vertebral artery to the internal carotid artery via the external carotid artery (ECA). We observed that the collateral circulation could become stagnant due to neck extension in patients with CCAO.

Conclusion: Physicians should be aware of this phenomenon and preoperatively determine whether ischemic symptoms occur under neck extension in patients with CCAOs accompanied by intracranial aneurysms.