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M Haider, A Mohandas, T Khairalsaeed, K Shah Detroit Medical Center/ Wayne State University eEdE#: eEdE-125 Disclosures • Authors • • • • Maera Haider – Nothing to disclose Aravind Mohandas – Nothing to disclose Tagwa Khairalseed – Nothing to disclose Kamran Shah – Nothing to disclose Objectives • Assessing normal globe positioning on imaging • Review various causes of exophthalmos with typical findings on CT and/or MR imaging. • Review etiologies of enophthalmos with typical imaging findings Measuring Orbital Position on Imaging • Perpendicular distance from the interzygomatic line (IZL) to the posterior margin of the globe • 14% greater upper limit of normal for African Americans 5-12.8mm for Caucasians with Measuring position ..contd • Less commonly used method: Globe protrusion anterior to the IZL on axial CT imaging at level of the lens • ≥ 21mm proptosis • Persons of African ancestry may have an upper limit of 14.5% higher than Caucasian counterparts • Clinically, the Hertel exophthalmometer most commonly used for measurements, however CT demonstrates better accuracy Exophthalmus - Causes • Most common cause: Thyroid orbitopathy • Infectious • preseptal vs orbital cellulitis • fungal • Inflammatory conditions • Pseudotumor • Vasculitis • Lacrimal gland disease • Orbital tumors • Vascular malformations • Varices • Carotid-cavernous fistulae Thyroid disease Exophthalmos • Most commonly occurs with Graves disease. Hashimotos is also an association • Usually bilateral and symmetric • Inflammation and hypertrophy of the EOM with sparing of tendinous insertion • Likelihood of muscle involvement: Inferior rectus > Medial rectus > Superior rectus > Lateral rectus • Increased orbital fat due to edema and inflammation reduced attenuation • Size of muscle correlates with severity of disease • May result in mass effect on optic nerve • On MR, EOM may appear T2 intense when actively inflamed; enhancement may or may not be present Thyroid disease Exophthalmos 72 yo man with long-standing history of Graves disease and thyroid orbitopathy now resulting in restrictive myopathy, underwent forced duction and medial rectus recession bilaterally Inferior Medial Superior Lateral Obliques Infection: Pre-septal & Orbital Cellulitis Exophthalmos • Accounts for majority of primary orbital disease • Presents with proptosis, painful ophthalmoplegia, reduced visual acuity • Source: contiguous spread from teeth, face, or paranasal sinuses • Most common: ethmoid sinus • Imaging findings on CT: • Loss of fat planes with stranding • Edema of surrounding soft tissue as well as intra-orbital structures • +/- abscess formation • MR imaging is rarely necessary. Will demonstrate high T2 and low T1 signal, diffusion restriction and peripheral enhancement in case of abscess • Complications: cavernous sinus thrombosis, meningitis, thrombosis of superior orbital vein, abscess formation, vision defects Orbital cellulitis 13yo girl with headache, fever, left eye Exophthalmos swelling greater than right, and AMS. Pre and post septal edema involving intra and extraconal regions with L>R proptosis Diffuse opacification and restricted diffusion of sphenoid & ethmoid sinuses indicating acute disease with purulent material T2WI T1WI enhanced T1WI Pachymeningeal enhancement around temporal and frontal convexities - meningitis Bilateral nonenhancing cavernous sinuses are hypointense on T1 and T2 with diffusion restriction indicating purulent material Lacrimal gland disease Exophthalmos • Lacrimal gland is composed of epithelial and lymphoid tissue, predisposing to corresponding pathologic processes • Bilateral disease • Inflammatory: sarcoidosis, histiocytosis • Malignancy: lymphoma, leukemia • Unilateral disease • Infection • Malignancy: primary or metastatic such as adenocarcinoma Lacrimal gland disease 48 yo man with right proptosis and pre-orbital swelling with blurry vision for past 3 years. Exophthalmos Asymmetric thickening and infiltration of right eyelid, preseptal soft tissue, lacrimal gland and mild enlargement of EOM Differentials include • Chronic adenitis with overlying cellulitis • Pseudotumor involving lacrimal gland and EOM • Lymphoma • Sarcoid thought unlikely due to unilaterality On biopsy of lacrimal gland: Non-caseating granuloma – sarcoidosis On body imaging, found to have pulmonary fibrosis but no lymphadenopathy or heaptosplenomegaly Orbital varices • Secondary: due to acquired increased flow • Atriovenous malformation • Carotid cavernous fistula (CCF) • Primary: congenital and confined to orbital cavity; rare • • • • • • Usually not symptomatic until 3rd decade of life ‘Intermittent’ proptosis or diplopia with Valsalva phenomenon/straining Thin walled and distensible Eventually may cause atrophy of orbital fat resulting in enophthalmos Diagnosis: Color flow sonogram, MRI and CECT – with and without Valsalva CT findings • Phleboliths (on non-contrast) • Ehancement of varix • MR will show T1 and T2 hypointensity when no thrombosis • Heterogenous hyperintensities when thrombosed Exophthalmos Carotid cavernous fistula 82 yo woman post MVA with nondisplaced C2 fracture, developed AMS day after event Significant flow related enhancement ICA shunting of cavernous sinuses, superior orbital veins and retro-clival venous plexus. Retro-orbital fat stranding is present. Cerebral angiogram performed with plan to embolize any Orbital congestion amenable lesion. Imaging revealedwith bilateral transected internal associated of segments with carotid arteries at petrocavernousenlargement and cavernous the EOM direct CC fistula. Determined too extensive for safe endovascular DWI and ADC: Extensive cerebral watershed distribution of infarctions treatment. secondary to hypoperfusion from the CCF. Made hospice, patient expired soon after. Left: Image from angiogram on the left demonstrates attenuated flow distal to the cavernous sinus Exophthalmos Sphenoid wing dysplasia Exophthalmos • High association with neurofibromatosis type 1 • Present in up to 10% of NF-1 • Diagnostic criteria for NF-1 • Imaging Findings: • • • • Absent or hypoplastic sphenoid wing Widened superior orbital fissure Expansion of middle crania fossa, often associated with arachnoid cysts Herniation of intracranial structures into the orbital cavity results in proptosis, and occasionally pulsating proptosis Sphenoid wing dysplasia 25 yo woman with known NF1 Enhancing soft tissue mass involving left temporalis muscle and periorbital structures infiltrating fat – consistent with plexiform neurofibroma Inferior herniation of temporal lobe. If Deformity of left middle cranial herniation occurs into the orbital cavity, it fossa secondary to sphenoid wing may result in pulsatile proptosis dysplasia and calcified proptosis Elongation of left globe axis Exophthalmos Orbital Pseudotumor • Usually unilateral in adults, bilateral in children • Diagnosis of exclusion • Can involve: extra-ocular muscles (most commonly), other retrobulbar structures, sclera, uvea, lacrimal glands • Findings: • Moderate diffuse irregular enlargement of structures with enhancement • Slight hyperintensity on T2 and STIR • Relative hypointensity to other orbital lesions suggests fibrosis • In chronic disease, decreased intensity suggests sclerotic variant and therefore worse prognosis • If only EOM involved, may resemble thyroid orbitopathy, however tendons are involved in case of pseudotumor and presentation is typically painful • Extensive differentials: sarcoidosis, systemic lupus erythematosus, dermatomyositis,rheumatoid arthritis, lymphoproliferative conditions, Wegener’s, cellulitis • Tolosa-Hunt is a variant that involves the cavernous sinus Pseudotumor T2 hyperintensity and enhancement showing edema and inflammatory infiltration extending along the right optic nerve sheath with involvement of the intraconal fat, medial and superior rectus muscles Exophthalmos T1WI Fat suppressed T1WI with contrast - axial T2WI 56 yo woman with 1 year history of proptosis and swelling. Negative work-up for inflammatory and malignant etiologies. Diagnosis: Idiopathic Orbital Inflammatory Syndrome Fat suppressed T1WI with contrast - coronal Orbital tumors Exophthalmos • Primary – intraconal vs extraconal • Nerve /sheath tumors – low T1 and high T2 signal typically with enhancement • Neurofibroma • Solitary – no association with NF-1, easily resectable. Undistinguishable from schwannoma on imaging. • Diffuse – may be associated with NF-1, extensive involvement of intraorbital structures may be present • Plexiform – pathognomonic for NF-1 • Schwannoma • Paraganglioma • Optic nerve glioma • Usually low grade, especially in children <5yrs, likely pilocytic, often bilateral • High grade in adults, likely glioblastoma multiforme or anaplastic • On MRI: fusiform enlargement of optic nerve; isointense on T1 and T2 when restricted to orbit, higher signal when involves optic chiasm • Meningioma • Circumferential thickening of nerve sheath with uniform enhancement. ‘Tram track’ sign with nonenhancing central nerve Orbital Tumors: continued • Primary contd • Mesenchymal • Cavernous hemangioma: most common benign orbital tumor. Well-delineated and enhancing on CECT, low signal on T1, high signal on T2. Rarely recur after resection • Lymphangioma: hemorrhage often hence heterogenous T1 and T2 signals with minimal enhancement • Hemangiopericytoma, rhabdomyosarcoma, fibrous histiocytoma • Rare: fibroma, fibrosarcoma, lipoma, leiomyoma etc • Secondary – contiguous spread from adjacent structures • Osteoma, ossifying fibroma, aneurysmal bone cyst • Metastasis • Represent 2.5 – 3.7% of all orbital tumors • Most common sources are breast, lung and prostate Orbital tumor – optic glioma Exophthalmos 2 yo boy with right proptosis and optic cupping on clinical examination Images on the right demonstrate a T2 hyperintense mass expanding the optic sheath with small amount of peripheral fluid preserved. Normal appearance of optic chiasm. T2WI Images on the left depict the marked optic edema in the right eye compared to the left. No other stigmata of NF1 were present in this patient. Pathology revealed: Pilocytic astrocytoma WHO grade 1 T1WI Sphenoid wing meningioma Exophthalmos 30 yo man with history of right sphenoid wing meningioma for which he underwent debulking and radiation therapy. Now with visual disturbance and proptosis MRI shows a large lobulated Remote post-operativeheterogenous craniotomy extraaxial mass in middle cranial fossa involving changes with extensivertsclerosis greater and hyperostosis of skull base and and lesser wing of sphenoid. Transcranial spread to sphenoid wing due to osseous right infratemporal fossa infiltration A large enhancing intra- and extracranial meningioma is visualized encroaching into the cavernous sinus, right superior and inferior orbital fissures. Crowding at the apex results in mass effect on optic nerve. Metastasis of Ovarian Origin Exophthalmos 61 yo woman with history of papillary serous ovarian cancer and worsening left eye pain with abnormal ophthalmologic exam MRI reveals an enhancing mass in muscle belly of left medial rectus. Focal enhancing mass also noted in superior rectus belly. The lateral and inferior rectus muscles, orbital fat, globes and optic nerves are unremarkable Metastasis of Nasopharyngeal Origin Exophthalmos 56 yo M with history of swelling and ulceration along roof of mouth. Found to have tumor along tongue and palatine tonsils as well as multiple neck nodes. PET/CT revealed FDG avid spots on nasopharynx. Underwent chemotherapy and radiation. Subsequent PET revealed progression of disease. Went on to develop headache and proptosis. Enhancement of the right temporalis on MR suggests further contiguous infiltration CT demonstrates a large infiltrating mass centered in the posterior right nasopharynx extending into the right orbital apex involving the medial and inferior orbit, along with extension to involve the sphenoid, right ethmoid and right maxillary sinuses Pseudoexophthalmos • Confounders to measurement of proptosis • Axial myopia: • Increased length of globe, unilateral or bilateral • Risk of retinal detachment • Congenital vs youth acquired vs adult onset • Buphthalmos: • Enlargement of globes without deformation or intraocular mass • Usually due to infantile glaucoma • Associated with neurofibromatosis type 1 • Shallow orbits: associated with multiple syndromes • Apert syndrome, Crouzon disease, Dubowitz syndrome, Edward and Patau syndromes, bone hyperostosis for eg. secondary to radiation injury Apert Syndrome • Rare; autosomal dominant and sporadic variants • Constellation of limb and skull malformations • Associated with CNS, GU and cardiac anomalies • Classic features: • Craniosyntosis • Facial hypoplasia • Syndactyly • Other features: • Harlequin eyes - elevation of the superolateral corner of the orbit • Hypertelorism – increased distance between the orbits Pseudo-exophthalmos Apert syndrome – 2 month old girl Pseudo-exophthalmos Hypertelorism is noted with bilateral harlequin appearance of the orbits. The shallow orbital cavity results in proptotic globes Imaging reveals increased craniocaudal dimension with bilateral shallow anterior cranial fossae and frontal bossing as well as bilateral croronal craniosynostosis. Enopthalmos: Causes • Most common cause: Trauma • Structural: • Maxillary sinus disease (silent sinus syndrome) • Bony defect (congenital, iatrogenic) • Fat atrophy • Age related or senile – bilateral and not uncommon • Systemic disease (lipodystrophy, scleroderma) • Post irradiation • Retraction • Metastasis (lung, gastric, scirrhous breast Ca) • Post-inflammatory Traumatic Enophthalmos Enophthalmos 53 yo M with history of left ‘proptosis’; imaged to evaluate for an orbital mass Upon CT imaging, discovered to have old fracture deformity of the right orbital floor and medial wall with herniation of orbital fat through the defect resulting in mild enopthalmos of right globe and relative exophthalmos of left globe. Minimal left globe proptosis due to abundant orbital fat without enlargement of lacrimal gland or EOM Silent Sinus Syndrome Enophthalmos • Severe maxillary sinusitis centripetal collapse aka atelectasis of sinus walls enophthalmos and hypoglobus (downward displacement of globe) • Often no history of sinusitis present • Always unilateral • Pathophysiology: negative pressure in the maxillary sinus due to resorption of secretions with concomitant sinus obstruction Silent Sinus Syndrome Enophthalmos Increased volume of orbital cavity with bowing of the orbital floor. Often the floor is thinned, and less frequently, can be absent Relative posterior displacement of globe Complete opacification of left maxillary sinus with reduced volume Bony defects - enophthalmos Enophthalmos • Most commonly, absence of greater wing of the sphenoid bone • Associated with neurofibromatosis type 1 • May also be present with epidermoid cyst, orbital varices, or iatrogenic • Complication: herniation of temporal lobe through the defect resulting in pulsatile enophthalmos • Imaging: complete or partial absence of GWS; widened superior orbital fissure; varices; associated optic glioma or plexiform neurofibroma • Pagets disease: enophthalmos is a rare manifestation – progressive bilateral receding globes due to bone remodeling Lipodystrophies Enophthalmos • Total vs partial vs localized • Enophthalmos most commonly occurs with partial dystrophy • Associations include Sjogren’s, lupus erythematosus, dermatomyositis • Most commonly, HIV-associated lipodystrophy – can result in severe atrophy of facial subcutaneous fat enophthalmos. Thought to be related to treatment rather than the disease • Post-irradiation resulting in fat atrophy later in life, most commonly post treatment for retinoblastoma or rhabdomyosarcoma as a child Traction secondary to Metastasis Enophthalmos • 7-24% of orbital metastasis results in enophthalmos rather than exophthalmos • Most commonly secondary to metastatic scirrhous breast carcinoma • Decreased ocular motility due to muscle infiltration • Desmoplasia, fibrosis, fat atrophy enophthalmos • Biopsy recommended even when known hx of carcinoma for treatment planning • Poor prognosis Metastatic Scirrhous Breast Carcinoma Tends to localize to the EOM and intra as well as extra conal fat as demonstrated. Presents in an irregular and diffuse fashion, extending along fascial planes When bone is involved, breast cancer tends to be more destructive than hyperostotic. This patient demonstrated both lytic and sclerotic regions in the calvaria Enophthalmos Restrictive muscle conditions Enophthalmos • Duane retraction syndrome is most common restrictive condition, however resultant enophthalmos is rare • Congential EOM fibrosis: rare, non-progressive, usually bilateral, usually familial. • Acquired retraction syndromes: rare, usually post-trauma Pseudoenophthalmos • Contralateral exophthalmos - Approx 50% of time unilateral enopthalmos initially results in investigation for ‘ contralateral exophthalmos’ • Micropthalmos • Facial asymmetry • Ptosis (eg. with Horner syndrome) References • Dollfus H and Verloes A. Dysmorphology and the Orbital Region: A Practical Clinical Approach. Surv Ophthalmol 49 (6) November–December 2004. 547-561. • de Juan, Jr E, Hurley DP, Sapira JD. Racial Differences in Normal Values of Proptosis. Arch Intern Med 1980; 140: 12301231. • Lloyd GAS. The Radiological Investigation of Proptosis. Br J Radiol 1970; 43: 1-18. • Fidor-Mikita E and Krupski W. Computed tomography imaging of orbits in thyroid orbitopathy. Journal of Pre-Clinical and Clinical Research, Vol 2, No 1: 59-63. • Ozgen A and Ariyurek M. Normative Measurements of Orbital Structures Using CT. AJR: 170, April 1998: 1093-1096. • Lee JS, Lim DW, Lee SH, Oum BS, Kim HJ, Lee HJ. Normative measurements of Korean orbital structures revealed by computerized tomography. Acta Ophthalmol Scand 2001; 79: 197–200. • Hilal SK, Trokel SL. Computerized tomography of the orbit using thin sections. Semin Roentgenol 1977; 12:137-147. • Sheikh M, Abalkhail S, Doi SA, Al-Shoumer KA. Normal measurement of orbital structures: implications for the assessment of Graves' ophthalmopathy. • Hira NK, Lipham WJ and Marciniak MM. Silent sinus syndrome. Optometry: Vol 75, No 9, September 2004, 589-594.Nontraumatic enophthalmos: a review Paul A. Athanasiov, Venkatesh C. Prabhakaran and Dinesh Selva • Athanasiov PA, Prabhakaran VC, Selva D. Non-traumatic enophthalmos: a review. Acta Ophthalmol. 2008 Jun;86(4):35664. • Garrity JA, Henderson JW. Henderson's Orbital Tumors, 4e. Lippincott Williams & Wilkins. (2007) ISBN:0781738695 The End.