C. Douglas Phillips MD FACR Director of Head and Neck Imaging Weill Cornell Medical College/NewYork-Presbyterian Hospital

Transcription

1 C. Douglas Phillips MD FACR Director of Head and Neck Imaging Weill Cornell Medical College/NewYork-Presbyterian Hospital

2 Disclosures Neither I nor any family members have any pertinent financial relations of note regarding material in this presentation Special thanks to Dr. Deborah Shatzkes for case material and ideas

3 The Orbit Brief Anatomy Orbital Trauma Orbital Infectious/Inflammatory Disease IOIS (orbital pseudotumor) Orbital cellulitis Vascular Lesions of the Orbit CCF Venous or lymphatic malformations Differential diagnoses of orbital disease

4 Bony Orbit and Foramina

5 Major Anatomic Compartments Globe Optic nerve and sheath Extraocular Muscles Lacrimal Gland Intraconal vs. Extraconal Compartment Preseptal vs. Postseptal Compartment

6 Globe and Optic Nerve Globe Divided into anterior and posterior segments by lens Optic nerve and sheath Orbital (tortuous) Intracanalicular Intracranial or intracisternal

7 Intraconal Compartment 4 rectus muscles and fibrous septa make up muscle cone Extraocular muscles originate from common tendinous ring (annulus of Zinn) in orbital apex Contains optic nerve, vessels, CN III, IV and VI and retrobulbar fat

8 Extraconal Compartment Outside muscle cone Between bony orbit and rectus muscles Contains lacrimal gland and fat

9 Globe Medial rectus Optic nerve Lateral rectus Ophthalmic artery Anterior clinoid Carotid artery

10 Orbital Apex Anterior clinoid process Optic nerves Sphenoid sinus (air filled) Superior orbital fissure

11 Lacrimal Sac Nasolacrimal apparatus has close relationship with ethmoid air-cells Nasolacrimal duct Drains into inferior meatus Protected by bony canal Normally may be opacified with fluid or contain air

12 Orbital Trauma Fractures involving orbit are common and can be urgent Thin section CT with MPR is necessary to depict and detail these fractures Soft tissue injuries are often overlooked but can be more serious

13 Retinal versus Choroidal Detachment Retinal Choroidal

14 Retinal versus Choroidal Detachment Retinal Choroidal

15 S/P assault w/ blunt and sharp instruments, multiple stab wounds: ruptured globe, retinal detachment

16 Fall w/ eye injury: choroidal detachment + hemorrhage, vitreal hemorrhage, dislocated cataract lens

17 Orbital Fracture with Orbital Hematoma Must review soft tissue windows

18 Orbital Infectious/Inflammatory Diseases Infections of orbit 60% of primary orbital disease Often complication of sinusitis Superficial tissues most commonly Extraconal and preseptal Can extend and involve intraconal soft tissues and/or CNS Immunocompromised hosts remember fungal disease

19 Orbital Inflammatory Disease Wide range of immunologic conditions may affect orbit Remember orbital involvement with systemic immunologic diseases Cross-reactivity of many immune complexes with orbital structures

20 Stages of Orbital Cellulitis Inflammatory edema/pre-septal cellulitis Post-septal disease Subperiosteal phlegmon/abscess Orbital cellulitis Orbital abscess Ophthalmic vein and cavernous sinus thrombosis

21 Pre-septal Orbital Cellulitis Erythema, pain, conjunctivitis, blurred vision 80% <10 years of age Staph/Strep are common organisms Imaging: CT with contrast indicated in patients with unreliable physical exam due to age or signs of post-septal involvement MR if accessible

22 Orbital Cellulitis Extension from periorbital structures or preseptal infection Mortality/morbidity very low Pre-ATBX: 17% mortality, 20% blind in affected eye Now estimated <1% Complications arise from progressive disease Subperiosteal/orbital abscess (7-9%) Ophthalmic vein/cavernous sinus thrombosis (50% mortality) Intracranial abscess

23 Pre-septal Orbital Cellulitis

24 Post-septal Orbital Cellulitis

25 Pre- and Post-Septal Orbital Cellulitis

26 Invasive Fungal Sinusitis Orbital Abscess

27 Invasive Fungal Sinusitis Orbital Abscess

28 Orbital Inflammatory Conditions Primary considerations Idiopathic orbital inflammatory disease (IOID), or orbital pseudotumor Thyroid orbitopathy Mixed, collagen-vascular diseases, and other orbital inflammatory conditions Sjogren s, sarcoid, etc. Granulomatosis with polyangiitis (Wegener s)

29 Orbital Pseudotumor Most common intraorbital mass lesion in adults Inflammation of ANY orbital structure of unknown cause Fat - 76% Muscles - 57% Optic nerve - 38% Uvea/sclera - 33% Lacrimal gland - 5% Two types: Tumefactive (diffuse) and myositic Tends towards transcompartment involvement

30 IOID or Orbital Pseudotumor Tumefactive pseudotumor Over 2/3rds of cases Infiltrating more common than focal disease 75% retrobulbar, with or without muscle cone involvement Myositic pseudotumor Second most common pattern Unilateral involvement Involves tendinous insertions

31 IOID or Orbital Pseudotumor Imaging Distinguish tumefactive type from neoplasia Distinguish pseudotumor from thyroid orbitopathy CT Intense enhancement of conal/intraconal lesions Involvement of muscle tendons MRI Lesions are hypo- to isointense to fat on T2 (other neoplasia often hyperintense to fat on T2) Intense enhancement NB: Can look like ANYTHING!

32 IOID or Orbital Pseudotumor

33 IOID or Orbital Pseudotumor

34 IOID or Orbital Pseudotumor

35 IOID or Orbital Pseudotumor

36 Myositic IOID Orbital Pseudotumor Following Steroids

37 Orbital Pseudotumor same diagnosis, different species

38 Granulomatosis with Polyangiitis (Wegener s) Note sinus disease!

39 Optic Neuritis Optic nerve inflammation due to: Demyelination (MS) Infections: Lyme disease, TB, syphilis Viral: HIV, HBV, herpes, CMV 50% of patients diagnosed with MS Long term severe vision loss in 20% Triad of symptoms: loss of vision, eye pain, dyschromatopsia; 70% unilateral

40 Optic Neuritis

41 Optic Neuritis Intracranial WM Lesions

42 Orbital Vascular Lesions Cavernous hemangioma (orbital venous malformation) is most common orbital mass in adults Emergent presentation may be seen with a limited number of orbital vascular lesions

43 Orbital Venous Malformation (Cavernous Hemangioma) Most common orbital vascular lesion in adult Classic imaging appearance in most cases 80% intraconal - usually retrobulbar CT Homogeneous, slightly hyperdense (microcalcifications) Usually marked homogeneous enhancement MR Isointense to muscle on T1 Hyperintense on T2 Patchy enhancement that may progressively opacify

44 Cavernous Hemangioma

45 Cavernous Hemangioma Immediate Post Contrast One hour Post Contrast

46 Carotid Cavernous Fistula Communication between ICA and cavernous sinus Indirect CCF AV shunting via multiple dural arteries Usually spontaneous Most often in middle-aged women Rare secondary to vascular tumor Direct CCF Post-traumatic (arterial laceration) Rupture of cavernous carotid aneurysm

47 Carotid Cavernous Fistula Pulsatile exophthalmos, chemosis, bruit Imaging findings Dilatation of SOV Exophthalmos with enlargement of EOM Abnormal contour (bulging) of CS CT and MR typically diagnostic CTA/MRA superior in depiction Catheter angiography for morphology and treatment

48 Observations Bulging wall of cavernous sinus Too many flow voids in cavernous sinus Dilated ipsilateral SOV

49

50 Catheter Angiography Indirect CCF

51 Direct CCF Post-Traumatic

52 Orbital Varices Supine Hanging Head

53 Lymphatic Malformations Lymphocytes may proliferate during viral infections and cause worsening proptosis Hemorrhage, either spontaneous or secondary to minor trauma, is common Results in chocolate cysts Sudden proptosis, rare optic nerve compression

54 Orbital Lymphatic Malformation

55 Orbital Lymphatic Malformation

56 Orbital Lymphatic Malformation

57 Orbital Disease: Patterns Lesion of bony orbit that involves orbit Enlargement of the extraocular muscles Retrobulbar mass Retrobulbar infiltrate

58 Lesion of Bony Orbit

59 Child Adult Mets (neuroblastoma, sarcomas) Leukemia/lymphoma Rhabdomyosarcoma Histiocytosis Fibro-osseous lesion Expansile PNS process Mets (lung, breast, melanoma, renal) Multiple myeloma Meningioma Leukemia/lymphoma Fibro-osseous lesion Expansile PNS process

60 Enlargement of Extraocular Muscles

61 EOM Enlargement Thyroid orbitopathy Idiopathic Orbital Inflammatory Syndrome (pseudotumor) Metastatic disease Infection Lymphoproliferative disease Vascular lesions

62 Retrobulbar Mass

63 Retrobulbar Masses Hemangioma Lymphangioma Met Lymphoproliferative disease Hematoma Schwannoma/neurof ibroma Rhabdomyosarcoma Chloroma Hemangiopericytoma Meningioma Optic n. lesions Epidermoid/dermoid/ Teratoma

64 Retrobulbar Infiltrate

65 Orbital Infiltrative Processes Infection Hemorrhage Lymphoproliferative disease Pseudotumor Sarcoid Wegeners Metastatic Disease CCF/SOV thrombosis Thyroid orbitopathy

66 Narrowing Your DDx Know clinical setting Know patient s age