a narrow notch between the cerebellar hemispheres posteriorly, occupied by the falx cerebelli. Synonym(s): incisura cerebelli posterior, marsupial notch, posterior notch of cerebellum

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bvl: biventral lobule; cmf: cerebellomedullary fissure Ivv: inferior vermin vein; pci: posterior cerebellar notch or incisura; T: tonsil; V: vallecula of the cerebellum; M: medulla.