MR imaging of orbital inflammatory pseudotumors with extraorbital extension.
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.
Lee
Eun Ja
EJ
Department of Radiology, Kwandong University, College of Medicine, Myongji Hospital, Korea. ejl1048@hanmail.net
Jung
So Lyung
SL
Kim
Bum Soo
BS
Ahn
Kook Jin
KJ
Kim
Young Joo
YJ
Jung
Ae Kyung
AK
Park
Chan Sub
CS
Song
Soon-Young
SY
Park
Noh Hyuck
NH
Kim
Mi Sung
MS
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