Delayed Establishment of Collateral Circulation from Posterior Meningeal Artery After Proximal Occlusion of Posterior Inferior Cerebellar Artery: Case Report and Literature Review

A report about this rare condition suggested that after occlusion of the PICA trunk, the distal PICA can form collateral circulation with the PMA. A potential collateral circulation may be present in advance between the PICA and PMA. When ischemia occurs in the distal PICA, this collateral circulation may open and could be reconstructed and enlarged to provide blood supply.