The posterior inferior cerebellar artery (PICA) is a vessel located between the intra- and extracranial circulation. The artery is characterized by a complex embryological development and numerous anatomical variants. The authors present a case of the PICA supplied by both a hypertrophic anterior spinal artery and a hypoplastic bulbar artery. This unusual arrangement somehow completes the list of previously published variants, and the spontaneous rupture of a related aneurysm confirmed the fragility of this network. The authors discuss anatomical and treatment considerations.
Keywords: AICA = anterior inferior cerebellar artery; ASA = anterior spinal artery; DSA = digital subtraction angiography; LSA = lateral spinal artery; PICA = posterior inferior cerebellar artery; Wallenberg syndrome; aneurysm; anterior spinal artery; interventional neurosurgery; lateral spinal artery; posterior inferior cerebellar artery; posterior medullary segment; tonsillomedullary segment; vascular disorders; vasocorona.