title: Intracisternal neurinoma of the C1 posterior root.
abstract: We report a rare intracisternal C1 posterior root neurinoma in a 35-year-old man without neurofibromatosis who presented with headache, nuchal pain, bilateral motor weakness of the upper extremities, and numbness in the right distal upper extremity. CT and MRI study showed a 20-mm intracisternal lesion at the foramen magnum. At surgery, there was an anastomosis between the C1 posterior root and a spinal accessory nerve at the site of the tumor; the root from the collateral sulcus of this C1 root was absent. Postoperatively, the patient remains free of symptoms. Foramen magnum neurinomas have been described as accessory nerve tumors. We present new anatomical consideration regarding this lesion.
authors.affiliation: Department of Neurosurgery, Neurological Institute, Nippon Medical School, Chiba Hokuso Hospital, Japan. takumi@nms.ac.jp
authors.forename: I
authors.initials: I
authors.lastname: Takumi
authors.forename: K
authors.initials: K
authors.lastname: Isayama
authors.forename: R Y
authors.initials: RY
authors.lastname: Osamura
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
authors.forename: A
authors.initials: A
authors.lastname: Teramoto
mesh_terms: D000055:Accessory Nerve / Q000473:pathology; D000328:Adult; D001270:Cervical Atlas / Q000033:anatomy & histology / Q000601:surgery; D002946:Cisterna Magna / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D005539:Foramen Magnum / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008526:Medulla Oblongata / Q000033:anatomy & histology / Q000601:surgery; D018908:Muscle Weakness / Q000209:etiology / Q000503:physiopathology; D019547:Neck Pain / Q000209:etiology / Q000503:physiopathology; D009442:Neurilemmoma / Q000098:blood supply / Q000175:diagnosis* / Q000601:surgery; D019635:Neurosurgical Procedures; D010264:Paraplegia / Q000209:etiology / Q000503:physiopathology; D011859:Radiography; D013125:Spinal Neoplasms / Q000098:blood supply / Q000175:diagnosis* / Q000601:surgery; D013126:Spinal Nerve Roots / Q000473:pathology* / Q000503:physiopathology; D013346:Subarachnoid Space / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D016896:Treatment Outcome; D014711:Vertebral Artery / Q000033:anatomy & histology / Q000601:surgery