Accessory nerve schwannoma classification
The spinal accessory nerve has a cisternal, a foraminal (jugular) and an extracranial course. The tumors can be anywhere along this course.
Spinal accessory nerve schwannomas are classified accordingly by their origin as cisternal, foraminal or extracranial/cervical 1) 2).
The intracranial accessory nerve schwannomas could be either of the jugular foramen type, the intracisternal type, or of the cervical type. The lower cranial nerves which include the glossopharyngeal nerve, the vagus and the accessory nerve, form a complex at the jugular foramen, which is defined as a jugular foramen schwannoma without the identification of the individual cranial nerve 3).
1)
Agrawal A, Rao KS, Makannavar JH, Shetty L, Raveendra VM. Intrasternomastoid spinal accessory nerve schwannoma: Clinical and radiological correlation. Neurol India. 2005;53:347–8.
2)
Hatashita S, Mitsuhashi T, Kurosu A, Ueno H. Schwannoma of the spinal accessory nerve: Case report. Neurol Med Chir (Tokyo) 2003;43:501–4.
3)
Julow J. Neurinoma of spinal accessory nerve. Report of two cases. Acta
Neurochir (Wien). 1983;69(3-4):219-24. PubMed PMID: 6650236.