[Ruptured Internal Carotid Artery Aneurysm Coiling in a Patient with Ipsilateral Internal Carotid Artery Occlusion via the Posterior Communicating Artery].

: aneurysms after internal carotid artery(ICA)occlusion occur in the contralateral ICA or anterior communicating artery. Hemodynamic changes with increased blood flow to the contralateral carotid circulation were considered the main factor for the formation of these aneurysms. We report a rare case of ruptured ICA aneurysm associated with ipsilateral ICA occlusion treated with coil embolization via the vertebrobasilar and posterior communicating arteries. :An 82-year-old woman presented with sudden-onset disturbance of consciousness at our outpatient clinic and went into cardiopulmonary arrest. Computed tomography(CT)performed after cardiopulmonary resuscitation revealed diffuse subarachnoid hemorrhage. Three-dimensional CT angiography revealed a right ICA aneurysm associated with the ipsilateral ICA occlusion. Considering that the patient showed clinical improvement with the critical care for neurogenic pulmonary edema, the aneurysm was treated with endovascular coil embolization via the posterior communicating artery. With this technique, complete obliteration was attained without perioperative complication. :Endovascular coil embolization via the posterior communicating artery was proven effective as a treatment method for ruptured ICA aneurysms with ipsilateral ICA occlusion. Hemodynamic stress due to increased blood flow in the posterior communicating artery may play an important role in the growth and rupture of ICA aneurysms.