title: Intraneural perineurioma of the third cranial nerve: occurrence and identification. Case report.
abstract: Intraneural perineurioma is a true but rare neoplasm that originates from perineurial cells and mainly affects peripheral nerves. It must be distinguished from other hypertrophic neuropathies that are either inflammatory or demonstrate an onion-bulb formation that originates from Schwann cells. Complying with this strict definition, only three additional cases of cranium-related perineurioma have been identified: two lesions arose extracranially and involved cranial nerves, and one occurred intracranially but did not involve a nerve. The authors describe a 27-year-old woman who presented with left third cranial nerve palsy and was found to harbor a mass lesion in the superior orbital fissure and cavernous sinus. After subtotal resection had been performed, pathological studies confirmed the presence of perineurial tumor cells in a pseudo-onion bulb formation. The cells stained positively for epithelial membrane antigen but not for S100 protein, clearly distinguishing the disease from one that originates in Schwann cells.
authors.affiliation: Semmes-Murphey Clinic and Department of Neurosurgery, University of Tennessee Health Science Center, Memphis, Tennessee 38120, USA.
authors.forename: Rami
authors.initials: R
authors.lastname: Almefty
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Webber
authors.forename: Kenan I
authors.initials: KI
authors.lastname: Arnautovic
mesh_terms: D000328:Adult; D002426:Cavernous Sinus / Q000473:pathology / Q000601:surgery*; D003390:Cranial Nerve Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D018317:Nerve Sheath Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D015840:Oculomotor Nerve Diseases / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D009918:Orbital Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D010525:Peripheral Nerves / Q000473:pathology; D012583:Schwann Cells / Q000473:pathology