Transcript Orbital Pseudotumors

Orbital Pseudotumor:
Idiopathic Orbital Inflammation
Shiva Kambhampati
MS4,George Washington University School of Medicine/
University of North Carolina at Chapel Hill
Outline
What is Orbital Pseudotumor?
 Differential Diagnosis
 Case Presentation
 Radiological Findings and Analysis
 Orbital Pseudotumor Subtypes
 Treatment
 Conclusions

What is Orbital Pseudotumor?






First described in the 1900s
AKA “Idiopathic Orbital Inflammation”, or
“nonspecific Orbital Inflammatory Disease”
Nonmalignant space occupying lesion involves orbital
tissue and simulates a neoplasm
Diagnosis of exclusion, based on patient history,
clinical picture, response to steroids, and occasionally
by biopsy
Etiology unknown
3rd most common cause of orbital inflammation
Differential Diagnosis of Orbital
Inflammation

Inflammatory







Thyroid Opthalmopathy
Sarcoidosis
Wegener’s
Orbital Cellulitis
Abscess
Vasculitis
Neoplastic


Lymphoma
Metastases
Clinical Presentation
•Typically acute – but can be insidious
•Painful
•Usually unilateral
•No real pattern of muscle involvement
•Ocular findings include:
•Diplopia
•Decreased Visual Acuity
•Proptosis
•Edema
•Absent systemic symptoms
Imaging Findings of Orbital Pseudotumor

Imaging findings are characterized by inflammatory changes
in orbital structures such as globe, lacrimal glands,
extraocular muscles, orbital fat, and the optic nerve.

MR findings:



Isointense on T1
Hypointense compared to normal muscle on T2
Enhancement on post-contrast T1 images
Case Presentation

62 y-o male dull ache in left eye and limited EOM


PMH: uveitis
Other Classical Clinical Presentations include:






Eye pain
Edema
Proptosis
Motility Restriction
Ophthalmoplegia
Lid Erythema
Case: Axial T1 Pre-Contrast
Axial T1 image shows isointense infiltrative process in left eye involving
the retro-ocular fat and external rectus muscle.
Case: Axial T2
Axial T2 image shows the process to be mostly hypointense. Note
proptosis.
Case: Axial T1 Post-Contrast
Post contrast T1 image shows the process to enhance and extend to
ipsilateral cavernous sinus and along dura of left middle cranial fossa.
Orbital Pseudotumor Forms






Dacryoadenitis
Myositis
Sclerosis
Optic Nerve involvement
Tolosa-Hunt Syndrome
Intracranial extension
Differential Diagnosis of Orbital
Inflammation

Inflammatory







Thyroid Opthalmopathy
Sarcoidosis
Wegener’s
Orbital Cellulitis
Abscess
Vasculitis
Neoplastic


Lymphoma
Metastases
Histology of Idiopathic Orbital Inflammation

Fibrous connective tissue and scant perivascular
patchy polyclonal lymphocytic infiltrates
Treatment

Systemic Corticosteroids


Radiotherapy




Usually rapid clinical response and resolution of pain
2nd line therapy
Adjuvant treatment when incomplete response
1st line therapy if steroids contraindicated
Immunomodulators/Immunosuppresants
Conclusions







Fairly common cause of orbital inflammation (3rd)
Diagnosis of Exclusion, other causes must be ruled
out
Occasionally diagnosis by biopsy is performed
Systemic Corticosteroids is primary treatment
Rapid response to steroid treatment supports
diagnosis of Orbital Pseudotumor
MRI better imaging modality for characterizing
intracranial extension
Orbital Pseudotumor is not a lymphoid tumor
Etiology



Etiology of Idiopathic Orbital Pseudotumor is unknown,
but there are some theories in the literature
Originally it was thought to be infectious in origin, with
historical reports occurring after viral illnesses.
Autoimmune pathogenesis was theorized because of a
strong association with and rheumatologic diseases.


Reports of circulating antibodies against extraocular muscle proteins
IgG4 Related Systemic Disease

Theory that links different inflammatory disorders that were
previously thought to be unrelated
IgG4 Related Systemic Disease (IgG4-RSD)


Systemic disease that is characterized by extensive IgG4positive plasma cells and T-lymphocyte infiltration of
various organs
Pancreatitis, sclerosing cholangitis, cholecystitis,
sialadenitis, retroperitoneal fibrosis, tubulointerstitial
nephritis, interstitial pneumonia, prostatitis, inflammatory
pseudotumor and lymphadenopathy, are all thought to be
IgG4-related


The prototype is IgG4-related sclerosing pancreatitis (also
known as autoimmune pancreatitis)
Disease usually responds well to steroid therapy
References






Yuen SJ, Rubin PA. Idiopathic orbital inflammation: distribution,
clinical features, and treatment outcome. Arch Ophthalmol
2003;121:491-9.
Lee et al. MR Imaging of Orbital Inflammatory Pseudotumors with
Extraorbital Extension.
Korean J Radiol. 2005 Apr-Jun; 6(2): 82–88.
Bencherif B, Zouaoui A, Chedid G, Kujas M, Van Effenterre R,
Marsault C. Intracranial extension of an idiopathic orbital
inflammatory pseudotumor. AJNR Am J Neuroradiol. 1993;14:181–
184.[PubMed]
Weber AL, Romo LV, Sabates NR. Pseudotumor of the orbit. Clinical,
pathologic, and radiologic evaluation. Radiol Clin North
Am. 1999;37:151–168. [PubMed]
Maksimovic O, Bethge WA, Pintoffl JP et-al. Marginal zone B-cell
non-Hodgkin's lymphoma of mucosa-associated lymphoid tissue
type: imaging findings. AJR Am J Roentgenol. 2008;191 (3): 921-30.
doi:10.2214/AJR.07.2629
Cheuk W. IgG4-related sclerosing disease: a critical appraisal of an
evolving clinicopathologic entity. Advances in Anatomic Pathology.
2010 Sep;17(5):303-32.