Spinal Accessory Nerve Meningioma at the Foramen Magnum with Medullar Compression: A Case Report and Literature Review.

BACKGROUND: Meningiomas that arise from the cranial nerve are rare. We present a case with an intradural extramedullary tumor at the foramen magnum originating from the spinal accessory nerve. CASE DESCRIPTION: The patient was a 69-year-old woman with dizziness and pain in the bilateral shoulder for 2 years. Neurologic examination revealed spinal accessory nerve palsy (difficult in raising the shoulder, deficit of 3/5) on the left side without further deficits. Magnetic resonance imaging showed medullar compression because of a left intradural extramedullary foramen magnum lesion dorsolateral to the medulla. Surgical exposure via a midline suboccipital approach with C1 laminectomy revealed that the lesion arises from the left accessory nerve without dural attachment. The tumor was resected without injury to the spinal accessory nerve, and histologic examination revealed that it was a meningothelial meningioma. The spinal accessory nerve palsy improved to 4 of 5 after 3 months after surgery. CONCLUSIONS: To our knowledge, this is the first report of an accessory nerve meningioma at the foramen magnum in which the spinal accessory nerve palsy appeared before operation and improved after tumor resection.

Schwannoma of the extracranial portion of the accessory nerve presenting as spinal adenopathy.

Schwannomas are benign tumours arising from Schwann cells in the peripheral nerve. The schwannoma of the accessory nerve is a very rare entity. We report a case of Schwannoma of the extracranial accessory nerve. A 22-year-old man presented with a slow-growing mass, located on the right upper neck. The patient did not have any neurological deficit. CT scan showed a hypodense mass behind sternocleidomastoid muscle. The suspected diagnosis was an adenopathy of the accessory spinal chain. Surgery was done via transcervical approach. The histopathological analysis concluded with a diagnosis of schwannoma. No recurrence was noted at the follow-up examination 29 months after surgery.

Spinal accessory neuropathy, droopy shoulder, and thoracic outlet syndrome.

Droopy shoulder has been proposed as a cause of thoracic outlet syndrome. Two patients developed manifestations of neurovascular compression upon arm abduction, associated with unilateral droopy shoulder and trapezius muscle weakness caused by iatrogenic spinal accessory neuropathies following cervical lymph node biopsies. The first patient developed a cold, numb hand with complete axillary artery occlusion when his arm was abducted to 90 degrees. The second patient complained of paresthesias in digits 4 and 5 of the right hand, worsened by elevation of the arm, with nerve conduction findings of right lower trunk plexopathy (low ulnar and medial antebrachial cutaneous sensory nerve action potentials). Spinal accessory nerve grafting (in the first patient) coupled with shoulder strengthening physical exercises in both patients resulted in gradual improvement of symptoms in 2 years. These two cases demonstrate that unilateral droopy shoulder secondary to trapezius muscle weakness may cause compression of the thoracic outlet structures.

Bilateral meningiomatous lesions of the spinal accessory nerves.

BACKGROUND: Meningiomas arising from cranial nerves with no dural attachment are exceedingly rare. The authors present a patient with bilateral meningiomatous lesions originating symmetrically from both spinal accessory nerves. CASE REPORT: A 61-year old woman presented with a one-year history of spinal ataxia and minimal left-sided motor impairment. Magnetic resonance imaging demonstrated two extrinsic lesions dorsolaterally of the medulla. Surgical exposure via a midline suboccipital approach with C1 laminectomy revealed the lesions arising from the spinal accessory nerves and in direct contact with the vertebral arteries. Histological investigation showed hypocellular fibrous lesions with proliferating meningothelial cells, psammoma bodies and immunoreactivity for vimentin, S-100 protein and epithelial membrane antigen. INTERPRETATION: To the authors' knowledge this is the first report of intradural tumours of the spinal accessory nerves not derived from Schwann cells and the first report of bilateral intracranial meningiomatous lesions without dural attachment.

Schwannoma of the spinal accessory nerve in the cisterna magna.

BACKGROUND: Intracranial schwannoma of the accessory nerve can be divided into two types. One is a jugular foramen type arising from the accessory nerve of the jugular foramen, while the other is an intracisternal type, which arises from the spinal root of the accessory nerve and is separate from the jugular foramen. The latter type is rare, and only 9 cases have been reported previously. CASE DESCRIPTION: A 46-year-old female presented with a large, midline mass lesion in the posterior fossa manifesting as foramen magnum syndrome. Magnetic resonance imaging (MRI) revealed a huge tumor with cystic lesion located in the cisterna magna with extension to the C1 spinal level. The tumor was totally removed by a suboccipital craniectomy and C1 laminectomy. It originated from the spinal root of the right accessory nerve. Temporary slight atrophy of the right sternocleidomastoid muscle was observed, but the patient was free of disease 2 years after treatment. CONCLUSIONS: We report a schwannoma of the spinal accessory nerve in the cisterna magna. The clinical and neuroradiological findings are discussed with a review of the literature. The initial symptoms were variable without loss of function of the cranial nerve, and the tumor tended to grow in the cisterna magna without laterality. Because of the absence of typical neurologic symptoms, early neuroradiological investigation by MRI is recommended for accurate diagnosis of these tumors.

Ultrasonography of the accessory nerve: normal and pathologic findings in cadavers and patients with iatrogenic accessory nerve palsy.

OBJECTIVE: To determine feasibility of ultrasonography in detecting the normal accessory nerve as well as pathologic changes in cases of accessory nerve palsy. METHODS: Four patients with accessory nerve palsy were investigated by ultrasonography. Three cases of accessory nerve palsy after lymph node biopsy and neck dissection were primarily diagnosed on the basis of ultrasonography using a 5- to 12-MHz linear transducer. In addition, we performed ultrasonography in 3 cadaveric specimens to show the feasibility of detecting the accessory nerve. RESULT: Nerve transection (n = 2), scar tissue (n = 1), and atrophy of the trapezius muscle (n = 4) were confirmed by electroneurographic testing and surgical nerve inspection. In 1 case in which a patient had a whiplash injury with accessory nerve palsy, ultrasonography showed atrophy of the trapezius muscle with a normal nerve appearance. CONCLUSIONS: Ultrasonography allows visualization of the normal accessory nerve as well as changes after accessory nerve palsy.