Coexistence of anterior choroidal artery and posterior cerebral artery retia mirabilia presenting with subarachnoid hemorrhage: illustrative case.

BACKGROUND: A rete mirabile is a rare vascular anomaly, with posterior cerebral artery (PCA) involvement being especially rare. Its pathogenesis has been speculated as a remnant of "distal annexation" between the primitive anterior choroidal artery (AchA) and the PCA at this site, but the exact mechanisms remain unclear. OBSERVATIONS: A 29-year-old man presented with subarachnoid hemorrhage. Arteriovenous malformation in the medial temporal lobe was initially suspected, but an arteriovenous shunt was not detected. First, conservative treatment was administered; however, rebleeding occurred 1 month later. Carotid angiography revealed a network-like cluster of blood vessels at the choroidal point of the AchA, suggesting a rete mirabile; these vessel clusters led to the persistent temporo-occipital branch of the AchA. Furthermore, an aneurysm was detected at the junction between the rete mirabile and the persistent temporo-occipital branch of the AchA. Additionally, vertebral angiography demonstrated a rete mirabile at the P2 segment. These findings suggested the coexistence of AchA and PCA retia mirabilia. Consequently, the aneurysm was clipped using a subtemporal approach to prevent re-rupture, and the postoperative course was uneventful. LESSONS: This first report of coexisting AchA and PCA retia mirabilia supports the remnant of distal annexation between the primitive AchA and the PCA as the reason for rete formation at this site.

Experience of using coronary perfusion balloon catheter for acute middle cerebral artery occlusion.

Background: We present the case of an individual with acute occlusion of the middle cerebral artery caused by atherosclerosis. The patient underwent angioplasty using a coronary perfusion balloon, which resulted in a favorable clinical outcome. Case Description: A 66-year-old male patient presented with an acute onset of right hemiplegia and dysarthria. Magnetic resonance imaging revealed an occlusion of the left middle cerebral artery, and alteplase was administered, followed by a mechanical thrombectomy and intracranial balloon catheter angioplasty. Due to restenosis, a coronary perfusion balloon catheter was used for a 15-minute angioplasty procedure while maintaining the perfusion. This treatment approach led to the recanalization of the artery and favorable clinical outcomes. Conclusion: The coronary perfusion balloon may represent a viable therapeutic alternative for the management of refractory intracranial atherosclerotic large vessel occlusion.

Ruptured Aneurysm Originating from a Posterior Inferior Cerebellar Artery Communicating Artery: A Case Report and Review of the Literature.

This report presents a rare case of such an aneurysm arising from such a communicating artery. A 66-year-old woman presented with a subarachnoid hemorrhage located predominantly in the cisterna magna with intraventricular hemorrhage. Angiography showed hypoplasia of the right posterior inferior cerebellar artery. Its vermian territory was supplied by the communicating artery from the posterior medullary segments of the left posterior inferior cerebellar artery. An aneurysm was on that communicating artery itself at a nonbranching site. The aneurysm was trapped the next day. Postoperative computed tomography showed no infarct in the right posterior inferior cerebellar artery territory. Trapping is applicable when other collateral vessels supply the contralateral posterior inferior cerebellar artery territory. J. Med. Invest. 67 : 197-199, February, 2020.

[A Case Report of Congenital Protein C Deficiency with Cerebral Venous Sinus Thrombosis during Early Pregnancy Period].

A 35-year-old woman at eight weeks of gestation in her second pregnancy presented with generalized seizures. Magnetic resonance images revealed a small hemorrhagic infarction in the left frontal lobe, and magnetic resonance venography indicated cerebral venous sinus thrombosis. After hospitalization, anticoagulant therapy was continued, and a low protein C level was confirmed, which was also confirmed in both her mother and her sister. Follow-up magnetic resonance venography performed on day 27 confirmed that the cerebral venous sinuses had undergone recanalization. After a completed gestation period, the patient gave birth to healthy girl uneventfully.