title: MR imaging of orbital inflammatory pseudotumors with extraorbital extension.
abstract: OBJECTIVE
  To demonstrate a variety of MR imaging findings of orbital inflammatory pseudotumors with extraorbital extension.
  
  
  METHODS
  We retrospectively reviewed the MR features of five patients, who were diagnosed clinically and radiologically as having an orbital inflammatory pseudotumor with extraorbital extension.
  
  
  RESULTS
  The types of orbital pseudotumors were a mass in the orbital apex (n = 3), diffuse form (n = 2), and myositis (n = 1). The extraorbital extension of the orbital pseudotumor passed through the superior orbital fissure in all cases, through the inferior orbital fissure in two cases, and through the optic canal in one case. The orbital lesions extended into the following areas: the cavernous sinus (n = 4), the middle cranial fossa (n = 4), Meckel's cave (n = 2), the petrous apex (n = 2), the clivus (n = 2), the pterygopalatine fossa and infratemporal fossa (n = 2), the foramen rotundum (n = 1), the paranasal sinus (n = 1), and the infraorbital foramen (n = 1). On MR imaging, the lesions appeared as an isosignal intensity with gray matter on the T1-weighted images, as a low signal intensity on the T2-weighted images and showed a marked enhancement on the post-gadoliniumdiethylene triamine pentaacetic acid (post-Gd-DTPA) T1-sequences. The symptoms of all of the patients improved when they were given high doses of steroids. Three of the five patients experienced a recurrence.
  
  
  CONCLUSIONS
  MR imaging is useful for demonstrating the presence of a variety of extraorbital extensions of orbital inflammatory pseudotumors.
authors.affiliation: Department of Radiology, Kwandong University, College of Medicine, Myongji Hospital, Korea. ejl1048@hanmail.net
authors.forename: Eun Ja
authors.initials: EJ
authors.lastname: Lee
authors.forename: So Lyung
authors.initials: SL
authors.lastname: Jung
authors.forename: Bum Soo
authors.initials: BS
authors.lastname: Kim
authors.forename: Kook Jin
authors.initials: KJ
authors.lastname: Ahn
authors.forename: Young Joo
authors.initials: YJ
authors.lastname: Kim
authors.forename: Ae Kyung
authors.initials: AK
authors.lastname: Jung
authors.forename: Chan Sub
authors.initials: CS
authors.lastname: Park
authors.forename: Soon-Young
authors.initials: SY
authors.lastname: Song
authors.forename: Noh Hyuck
authors.initials: NH
authors.lastname: Park
authors.forename: Mi Sung
authors.initials: MS
authors.lastname: Kim
mesh_terms: D000328:Adult; D002426:Cavernous Sinus; D035301:Cranial Fossa, Middle; D003388:Cranial Fossa, Posterior; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016727:Orbital Pseudotumor / Q000175:diagnosis* / Q000473:pathology; D010579:Petrous Bone; D012189:Retrospective Studies