title: Letter: Missed foramen-magnum tumours.
mesh_terms: D000783:Aneurysm / Q000000981:diagnostic imaging; D000792:Angiography; D003937:Diagnosis, Differential; D005539:Foramen Magnum / Q000000981:diagnostic imaging*; D006801:Humans; D009192:Myelography; D012888:Skull Neoplasms / Q000000981:diagnostic imaging; D013120:Spinal Cord Neoplasms / Q000000981:diagnostic imaging; D014711:Vertebral Artery / Q000000981:diagnostic imaging