BACKGROUND Compared with several reports of cerebral vasospasm after clipping for unruptured cerebral aneurysm, only one study to date has reported cerebral vasospasm after coil embolization. Herein, the authors report a rare case of cerebral vasospasm after coil embolization for unruptured cerebral aneurysm. OBSERVATIONS A 58-year-old woman with an unruptured anterior communicating artery aneurysm was referred to our department. Stent-assisted coil embolization was performed for the aneurysm, and no obvious adverse events were observed on cerebral angiography obtained immediately after the operation. However, the patient developed mild headache and slight restlessness soon after the operation and new-onset disorientation, left hemispatial neglect, and left hemiplegia the day after the operation. Emergency brain magnetic resonance imaging and cerebral angiography indicated vasospasm in the right middle cerebral artery, and intra-arterial injection of fasudil hydrochloride hydrate was performed to dilate the middle cerebral artery. Blood flow in the middle cerebral artery immediately improved, and she was discharged without neurological deficits 8 days after the operation. LESSONS Immediate intervention is necessary to prevent cerebral infarction in patients with cerebral vasospasm, which may occur even after coil embolization for unruptured cerebral aneurysm.

BACKGROUND Aortogenic embolism is one of the causes of embolic stroke of undetermined source, which can be difficult to diagnose. METHODS We present the case of a 74‐year‐old male patient with a history of Bentall surgery and thoracic endovascular aortic repair who was transported to our hospital with sudden‐onset right‐sided hemiplegia and total aphasia. Magnetic resonance imaging revealed an acute left middle cerebral artery occlusion. Subsequently, an emergency mechanical thrombectomy was performed, through which the left middle cerebral artery was partially reperfused. We immediately investigated the aorta using an angioscopy. RESULTS The angioscopy revealed a thrombus attached to an artificial blood vessel of the aorta close to the origin of the left common carotid artery. Because no other source of the embolus could be identified using electrocardiography or ultrasound, we diagnosed an aortogenic cerebral infarction by combining these findings with the pathological findings of the collected thrombus. CONCLUSIONS This is the first report that aortogenic cerebral infarction could be diagnosed using an angioscopy immediately after a cerebral artery thrombectomy.

Case presentation A 78‐year‐old man with a mobile lesion was diagnosed with thrombus using carotid ultrasonography, but the lesion was not completely resolved with dual antiplatelet and anticoagulation therapy. Direct visualization by angioscopy showed a white mobile plaque. The carotid artery was stented with a double‐layered stent, as the plaque persisted despite continuing the medical treatment and was linked to an increased risk of cerebral embolism. The plaque was attached to the arterial wall, and it subsequently disappeared. The patient recovered well and no further emboli were observed. Conclusions Angioscopy is effective for identifying lesions under direct vision. The characteristics and dynamics of plaques may be viewed via angioscopy, which aids in making treatment‐related decisions, particularly in the case of carotid artery plaques.