Jason B. Mueller, M.D.1 Lindell R. Gentry, M.D.2

Deborah L. Reede, M.D.3 Wendy R.K. Smoker, M.D.1

1University of Iowa Hospitals and Clinics, Iowa City, IA; 2University of Wisconsin Hospital and Clinics, Madison, WI; 3SUNY Downstate Medical Center, Brooklyn, NY

Doctor, What is Wrong with My Eye? Common and Uncommon Extra-ocular Lesions

A Case-Based TutorialeEdE-111

Financial Disclosure

Learning Objectives

• Learn the most common extra-ocular lesions of the orbit

• Become familiar with important, but less common orbital lesions that must also be considered in the differential diagnosis

• Learn the discriminating imaging features of these entities

Introduction

Case 1

Diagnosis?1. Dacryocystocele2. Dermoid cyst3. Lacrimal cyst4. Abscess

“Eyebrow mass”

• Represent ectodermal inclusion cysts.• Often contain primarily lipid, but may also

contain fluid and solid tissue, as in this case

• Most common location = superolateral orbit

• May produce mass effect on intraorbital contents and even cause bone remodeling

Case 2

Diagnosis?1. Perioptic meningioma2. Optic neuritis3. Optic nerve schwannoma4. Optic pathway glioma

(OPG)

22F with decreased vision OU

• 2/3 of all optic nerve tumors;3% of orbital tumors• OPGs : meningiomas = 4:1 • Present with proptosis and decreased visual acuity• Typically slow growing; >90% before age 20• Fusiform enlargement of the optic nerve with

variable enhancement• CSF is still visible within the ON sheath. There is

also posterior extension to the optic chiasm in this case

Case 2 continued

Of the following, this patient is most likely to have:1. Tuberous sclerosis2. Neurofibromatosis I3. Neurofibromatosis II4. Sturge-Weber

Syndrome

22F with decreased vision OU

• 10-35% of patients with optic gliomas have NF1

• Conversely, 15% of NF1 patients will have optic pathway gliomas

Case 3

Diagnosis?1. Meningioma2. Venous varix3. Cavernous malformation4. Abscess

44F with painless proptosis

Immediate post-contrast One hour delay

T1 pre-contrast T2• Most common adult intraconal lesion• Erroneously called “cavernous

hemangiomas”,--NOT true neoplasm • Present with painless proptosis that

slowly progresses. • T1=isointense ; T2=hyperintense +/-

hypointense fibrous pseudocapsule• Patchy CE on arterial phase, which

homogeneously fills in on delayed images

Cavernous Malformation companion case

• Phleboliths are not typical, but helpful when present

• Cavernous malformations require no treatment if asymptomatic

• Surgical resection is often curative if lesion is causing visual

• disturbances or significant mass effect

• Pseudocapsule facilitates removal of the lesion

T2

Immediate post Delay

Courtesy V Runge, MD

Case 4

Diagnosis?:1. Venous varix2. Orbital cellulitis3. Cavernous malformation4. Capillary hemangioma

6 month old with “eyelid swelling”

• AKA infantile hemangioma-most common orbital vascular TUMOR of infancy

• Growth phase (1-2 years); involutional phase (after 2 years); 50% involute by age 5.

• Steroid therapy is very effective and indicated for decreased vision/cosmesis.

• T1 isointense, T2 hyperintense• Homogeneous enhancement; flow voids

may be present

Case 5

Diagnosis?1. Venous varix2. Orbital cellulitis3. Cavernous

malformation4. Capillary hemangioma

Positional proptosis

• Result from dilation of orbital veins secondary to weakness of vessel wall

• Most common cause of spontaneous orbital hemorrhage.

• May be occult on imaging without provocative maneuvers. The abnormal veins become engorged during Valsalva or prone positioning

• Fluid-fluid levels may be present.• MR signal is variable on depending on the

age of blood products

Supine Prone

Case 6

Diagnosis?1. Carotid-cavernous fistula2. Orbital cellulitis3. Meningioma4. Lymphatic malformation

Progressive, painless proptosis

• Multilobulated, trans-spatial, enhancing mass composed of abnormal, dilated lymphatic channels

• Multiple fluid-fluid levels are characteristic • May hemorrhage rapid increase in size• Observation is the mainstay of treatment;

corticosteroids can be used for swelling/pain • Surgical resection difficult; high recurrence

rate

Case 7

Diagnosis?1. Carotid-cavernous

fistula (CCF)2. Orbital cellulitis3. Venous varix4. Venolymphatic

malformation

Chemosis, proptosis, and bruit

Ans. 1 Carotid-Cavernous Fistula

• Congested, hypervascular cavernous sinus

• Arterialized flow within the superior ophthalmic vein

• CCFs may be direct (trauma or ruptured cavernous ICA aneurysm) or indirect ( AVM or hypervascular tumor draining into the cavernous sinus)

• Worrisome signs of CCF include intracranial hemorrhage, cortical venous shunting, and rapid visual loss

Carotid-Cavernous Fistula

Most CCFs can be treated via an endovascular approach.

Arterialized superior ophthalmic vein

Post-coiling

Case 8

Diagnosis?1. Optic neuritis2. Optic nerve glioma3. Optic nerve infarction4. Perioptic meningioma

Diabetic, fever, abrupt vision loss OD

DWI

Ans. 3 Optic Nerve Infarction

• Note Rt ON diffusion restriction to the chiasm The nerve is also thickened and edematous

• Etiology of this patient’s symptoms was invasive fungal sinusitis (in this case mucormycosis), as evidenced by the extensive paranasal sinus disease

• Invasion of the ICA and its branches with resulting infarction is a known complication

DWI

Case 9

Diagnosis?:1. Metastases2. Thyroid associated

orbitopathy (TAO)3. Pseudotumor4. Sarcoidosis

Exophthalmos

Ans. 2 Thyroid Associated Orbitopathy

• Secondary to Grave’s disease • Most common orbital disorder and most

common cause of exophthalmos in adults.• Spindle-shaped enlargement and intense

enhancement of affected muscles• Distribution of extraocular muscles affected is

specific and remembered with the mnemonic “I’M SLO”; inferior, medial, superior, lateral recti, and obliques.

• Notice tendon sparing which is characteristic and a key distinguishing feature from pseudotumor.

Case 10

Diagnosis?:1. Metastases2. Thyroid associated

orbitopathy3. Pseudotumor4. Sarcoidosis

Acute, painful proptosis OS

Ans. 3 Pseudotumor

• Nongranulomatous idiopathic inflammatory disorder. Myositic (EOM) pattern (this case) is the most common

• Second most common orbital disorder after Grave’s disease; Acute, subacute, or chronic • Extraocular muscles become enlarged without a specific predilection, unlike TAO• Also unlike TAO, there is involvement of the muscle tendons • Treated with corticosteroids, to which there is usually a good response

Case 11

Diagnosis?1. Optic neuritis (ON)2. Optic nerve glioma3. Optic nerve infarction4. Perioptic meningioma

31F with acute decreased vision and pain OD

• Optic neuritis is an idiopathic autoimmune condition characterized by abrupt visual loss and orbital pain

• Corticosteroids accelerate initial recovery but do not alter long-term vision recovery

• Key imaging features include optic nerve enhancement, mild enlargement, and increased T2SI

Case 11 continued

What process is indicated by the yellow arrow?1. Chronic small vessel

ischemia2. Acute infarction3. Inactive demyelination4. Active demyelination

• ON is highly associated with multiple sclerosis (MS).• >50% of patients with ON develop MS, especially

women • MS plaques are demonstrated on the T2WI • Contrast enhancement demonstrated on the lower

image confirms that active demyelination is occurring

31F with acute decreased vision and pain OD

Case 12

Diagnosis?1. Optic neuritis2. Optic nerve glioma3. Optic nerve infarction4. Perioptic meningioma

Progressive, painless visual loss

Ans. 4 Perioptic Meningioma

• Typically present with slowly progressive, painless visual loss

• Marked T2 hypointensity, a characteristic feature• “Tram track” and circumferential intense,

homogeneous enhancement, also key findings. Note normal optic nerve

• Calcifications are present in up to 50% of cases often with “tram track” morphology as in bottom case (different patient)

Case 13

Diagnosis?1. Orbital cellulitis2. Uncomplicated

sinusitis3. Mucocele4. Subperiosteal

abscess

Fever, proptosis

• A complication of acute sinusitis, particularly ethmoid• Note opacification of maxillary sinus and ethmoid air cells, as well as dehiscence of the

lamina papyracea (often not present)• Abscess is seen as a rim-enhancing fluid collection abutting the medial orbital wall

displacing intraorbital contents. Note medial rectus myositis• Treatment consists of IV antibiotics and often surgical drainage, especially with

decreasing vision

Case 14

Diagnosis?1. Pseudotumor2. Thyroid associated

orbitopathy3. Metastasis4. Schwannoma

Former smoker, decreased “eye movement” OD

• Metastatic disease is favored in this case (note history!)

• Asymmetric involvement and lack of spindle-shaped EOM makes TAO less likely. Pseudotumor is typically accompanied by infiltration of orbital fat. A schwannoma should not be centered in an EOM.

• Note marked enlargement, enhancement, and hyperintense T2 signal of the inferior rectus muscle

Case 15

Diagnosis?:1. Optic neuritis2. Schwannoma3. Optic glioma4. Perioptic meningioma

Painless proptosis

Ans. 2 Schwannoma (V1)

• Relatively rare (1% of orbital tumors) • Benign and slow-growing painless proptosis• May be isolated or associated with NFII. Arise from

cranial nerves (excluding the optic nerve)• Fusiform to oval shape, iso to hypointense T1 signal

and hyperintense T2 signal; they avidly enhance uniformly

• Often displace the optic nerve (here inferomedially).• Note extension through the superior orbital fissure

into the cavernous sinus

Case 16Painless facial swelling; Diplopia on left lateral gaze

Diagnosis?1. Paget disease2. Ossifying fibroma3. Intraosseous

meningioma4. Fibrous dysplasia

Ans. 4 Fibrous dysplasia (FD)• Results when normal trabecular

bone is replaced by fibrous tissue and immature, woven bone.

• CT imaging findings include expanded bone with intact cortex and ground glass CT attenuation

• Classic MR features include hypointense T1 and T2SI and variable contrast enhancement.

• FD can be observed until there is functional impairment. Treatment consists of surgical excision, not usually attempted until after puberty

• Rarely, FD can undergo sarcomatous degeneration

Case 17

Diagnosis?1. Paget disease2. Ossifying fibroma3. Osteoma4. Meningioma

History withheld

Ans. 3 Orbital Roof Osteoma

• Mature, benign, slow-growing, osseous tumors.• Often asymptomatic and discovered incidentally.• Excision generally only required if mass effect • May be “ivory” and appear as dense, compacted

cortical bone, or “mature” with central marrow• This is an ivory osteoma: CT-marked uniform

hyperdensity; hypointensity on T1 and T2WIs. • Lesion displaces optic nerve inferolaterally Gardner syndrome must be excluded if a

patient is found to have multiple osteomas!

Case 18

Most likely diagnosis?:1. Langerhans cell histiocytosis (LCH) 2. Paget disease3. Intraosseous meningioma4. Fibrous dysplasia

Periorbital pain and swelling

Ans. 1 Langerhans Cell Histiocytosis (eosinophilic granuloma)

• Rare disorder characterized by the abnormal proliferation of Langerhans cells• Term eosinophilic granuloma is used for unifocal disease, as in this case. Two additional

syndromes, Hand-Schuller-Christian and Letterer-Siwe disease, refer to multifocal involvement within a single organ system and widespread multi-organ system disease, respectively

• Imaging includes “punched out” lytic lesions with associated homogeneous soft tissue mass, often creating a “beveled edge” appearance

• Orbital LCH is a risk factor for developing diabetes insipidus

Case 19

Diagnosis?1. Langerhans cell histiocytosis2. Neuroblastoma mets3. Intraosseous meningioma4. Fibrous dysplasia

“Raccoon eyes”, child with history of abdominal mass

• Frequently metastasizes to the skull. Although rare, bilateral metastases may produce “raccoon eyes” on physical exam

• Result in aggressive bony destruction. Extradural, intracalvarial extension can occur, as in this case.

• Avid contrast enhancement. There may also be significant mass effect on intraorbital contents, also present in this case

• Abdominal CT shows the primary tumor of heterogeneous density with calcification, typical of neuroblastoma

Ans. 2 Neuroblastoma Metastases

• Extra-ocular orbital lesions may present a diagnostic challenge to the radiologist, especially when atypical in appearance

• Careful inspection for characteristic distinguishing features will often lead to the correct diagnosis or significantly narrow the differential

• Consider both common and uncommon entities when faced with these cases

Summary

References

• Bahn RS. Graves' ophthalmopathy. N Engl J Med. 362(8):726-38, 2010.• Shams PN et al. Optic neuritis: a review. Int MS J. 16(3):82-9, 2009.• Smoker WR et al. Vascular lesions of the orbit: more than meets the eye. Radiographics.

28(1):185-204; quiz 325, 2008.• AnsariSA, Mafee MF. Orbital cavernous hemangioma: role of imaging. Neuroimaging Clin N Am.

2005; 15: 137–158.• Ruggieri M et al. Earliest clinical manifestations and natural history of neurofibromatosis type 2

(NF2) in childhood: a study of 24 patients. Neuropediatrics. 36(1):21-34, 2005.• Erly WK et al. Orbital histiocytosis X. AJNR Am J Neuroradiol. 16(6):1258-61, 1995.• Alexander AA et al. Paranasal sinus osteomas and Gardner's syndrome. Ann Otol Rhinol Laryngol.

116(9):658-62, 2007.

Contact Information

jason-b-mueller@uiowa.edu