[Juxtabulbar neurinoma of the spinal accessory nerve].

A 27-year-old woman presented with right spinal accessory juxtabulbar schwannoma, associated with hydrocephalus. The only specific clinical symptom was long-standing weakness of the right trapezius. C.T. scan evoked a cerebellar tumor, whilst the jugular foramen appeared normal. Vertebral angiography was not decisive. M.R.I. suggested an extra-axial tumor. Post-operative evolution was entirely favourable. Schwannomas of the 9th, 10th and 11th cranial nerves are generally located at the level of the jugular foramen but can also be observed along the extracranial path of these nerves. An intracranial paramedial, or so-called "intracisternal" localization is rare and is best diagnosed by magnetic resonance imaging.