Treatment for subarachnoid hemorrhage due to ruptured posterior cerebral arterial dolichoectasia with aortic arch anomaly

Subarachnoid hemorrhage (SAH) due to ruptured posterior cerebral artery (PCA) intracranial arterial dolichoectasia (IADE) is very rare. As these lesions are difficult to treat microsurgically, neurointervention is preferred because the dolichoectatic artery does not have a clear neck, and the surgical field of view was deep seated with the SAH. However, in some cases, neurointervention is difficult due to anatomical variation of the blood vessel to access the lesion. In this case, a 30-year-old male patient presented with a ruptured PCA IADE and an aortic arch anomaly. Aortic arch anomalies render it difficult to reach the ruptured PCA IADE via endovascular treatment. The orifice of the vertebral artery (VA) was different from the usual cases, so it was difficult to find the entrance. After only finding the VA and arriving at the lesion along the VA, trapping was performed. Herein, we report the PCA IADE with aortic arch anomaly endovascular treatment methods and results.