title: Orbital intramuscular schwannoma.
abstract: In an 8-year-old girl with asymptomatic proptosis, computed tomographic scans showed a large medial orbital mass that contoured the globe anteriorly, bowed the optic nerve laterally, and extended posteriorly to the orbital apex. T1-weighted coronal magnetic resonance images showed the mass to be a diffusely enlarged medial rectus muscle. Histopathologic examination of a medial rectus muscle biopsy specimen disclosed a multinodular, intramuscular schwannoma, separating and infiltrating normal skeletal muscle fibers. The intramuscular location and multinodular configuration of this tumor, together with its occurrence in a child, distinguish it from previous orbital schwannomas.
authors.affiliation: Department of Ophthalmology, University of Arkansas for Medical Sciences, Little Rock.
authors.forename: D H
authors.initials: DH
authors.lastname: Capps
authors.forename: M C
authors.initials: MC
authors.lastname: Brodsky
authors.forename: C D
authors.initials: CD
authors.lastname: Rice
authors.forename: R E
authors.initials: RE
authors.lastname: Mrak
authors.forename: C M
authors.initials: CM
authors.lastname: Glasier
authors.forename: H H
authors.initials: HH
authors.lastname: Brown
mesh_terms: D001706:Biopsy; D002648:Child; D005094:Exophthalmos / Q000209:etiology; D005133:Eye Movements; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D009442:Neurilemmoma / Q000175:diagnosis* / Q000601:surgery / Q000648:ultrastructure; D009801:Oculomotor Muscles / Q000601:surgery / Q000648:ultrastructure; D009918:Orbital Neoplasms / Q000175:diagnosis* / Q000601:surgery / Q000648:ultrastructure; D014057:Tomography, X-Ray Computed