2025 Volume 53 Issue 4 Pages 224-230
We report a case of spontaneous thrombosis of a ruptured intracranial aneurysm with an unruptured aneurysm in which we failed to recognize the ruptured aneurysm and treated the unruptured aneurysm, which resulted in its re-rupture.
A 61-year-old female with pain extending from the occiput to the back was admitted to the emergency department. She developed seizures in the emergency room and was referred to us because a head computed tomography (CT) scan revealed a diffuse subarachnoid hemorrhage. The 3D computed tomography (3DCTA) and catheter angiography revealed no lesions other than the left distal anterior cerebral artery (ACA) aneurysm, although the localization of the hematoma was atypical. We diagnosed a subarachnoid hemorrhage due to rupture of the distal ACA aneurysm and performed neck clipping. The patient presented with impaired consciousness on the 12th day of hospitalization. The 3DCTA and catheter angiography revealed an aneurysm of the right internal carotid artery, which was determined to be the lesion responsible for the first and second hemorrhages. Coil embolization was performed and the patient was transferred to a rehabilitation hospital with an modified Rankin Scale (mRS) score of 4.
Complete thrombosis of a small aneurysm following rupture is rare. Spontaneous thrombosis of ruptured aneurysms with multiple aneurysms is a risk factor for rebleeding because it circumvents further investigation. The existence of a thrombosed aneurysm should be considered when the pattern of hemorrhage is atypical, and appropriate imaging examinations should be repeated.
