This study reinforces the importance of using older animals for the researching and treatment of stroke. Elderly animals show differences in response mechanisms, ischemic consequences, and histological changes. These differences may partially explain the current lack of success involved in using young-animal models to predict the clinical efficacy of neuroprotective agents.

No abstract

Intracranial pseudoaneurysms are rare, particularly in children and adolescents. They are characterized by the presence of organizing hematoma and fibrosis without true vascular elements. Most pseudoaneurysms result from events such as major trauma or infectious illness, and the development of pseudoaneurysm without a preceding incident is rare. We here describe a patient with a large pseudoaneurysm arising in the distal middle cerebral artery. A 10-year-old boy experienced a sudden onset of headache, nausea, and vomiting followed by loss of consciousness and was referred to our medical center. Brain computed tomography showed massive subcortical hemorrhage in the left temporal lobe. Digital cerebral angiography revealed a huge aneurysmal dilatation of the distal left M1 segment of the middle cerebral artery, with delayed filling and emptying of contrast media. Surgical resection of the aneurysm with evacuation of the hematoma yielded restoration of consciousness. Although the cause of aneurysm in this case is uncertain, this type of patient is seldom encountered; its etiology and mechanisms of onset are discussed with reference to the literature.

This patient apparently was the lowest birth weight neonate with a large AVF successfully treated by embolization, which is usually performed through the transfemoral arterial route. The transumbilical arterial route is an alternative for neonates with birth weight <2000 g and very small femoral arteries.

Posterior cerebral artery (PCA) aneurysms are rare, and direct surgery of these is considered difficult. Coil embolization of PCA aneurysms is becoming popular. However, it is difficult to completely obliterate the aneurysm while preserving the flow of the parent artery in large or giant PCA aneurysms with a wide neck with this technique. We report a case of a large and wide-necked PCA aneurysm with multiple recurrences following successful surgical clipping and coil embolization. A 77-year-old man with a large unruptured right PCA (P2) aneurysm was successfully treated by surgical clipping. Postoperative digital subtraction angiography (DSA) showed complete aneurismal occlusion. Four years afterward, the aneurysm recurred and grew toward the contralateral. Surgical retreatment of this complicated aneurysm was considered difficult, with a substantial risk of complications. Therefore, the aneurysm was treated with an endovascular procedure. Because simple coil embolization was not expected to achieve satisfactory obliteration of the aneurysm with preservation of parent artery patency, we used stent-assisted coil embolization. The patient tolerated the treatment well. On DSA obtained six months after the first endovascular treatment, coil compaction and recanalization of the aneurysm were detected. A second coil embolization was successfully performed without any complications. The aneurysm was stable during the next six-month follow-up. Stent-assisted coil embolization may be feasible and effective for such postoperatively complicated aneurysms.