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Imaging of extraocular orbital pathology
BY : Ali Hekmatnia M.D
Imaging indications
• Ophthalmologist suspects pathology symptomatically or by sonography not exactly delineated
• In cases of trauma (e.g. foreign body, fractures)
• Posttreatment
Imaging modalities
• US
• CT – MDCT often working horse
• MRI
Imaging techniques CT
MDCT, axial, -/+ CM (depending on pathology), coronal/sagittal reconstructions, soft tissue/bone window level
MRIHeadcoil/surface coils, axial IR, axial T1wSE -/+ CM, coronal/sagittal T1wSE+CM+ FS, matrix 512x512, FOV ~20cm
- Axial and coronal images
- Axial 3mm sections
- Coronal 5mm sections- Coronal sections from the lateral
orbital rim to the posterior aspect of the
optic canals
(anterior clinoid or dorsum sellae)
CT Scan : TECHNIQUE
- Extraocular muscles , optic nerve
sheath , nasal complex ,vessels
and globes , Spread of processes
from surrounding structures
- Windowing : soft tissue as well as
bone-oriented window
Coronal images :
- Multiplanar capability , without ionizing radiation and
bony artifact(especially in the orbital apex,optic canal
and parasellar regions ) .Best soft tissue contrast.
- Protocol of MRI :
coronal and axial T1 and T2W images , coronal T1W
with fat saturation(before and after contrast injection )
MRI :
Anatomy of the Orbit Compartimental anatomy• Extraconal • Conal• Intraconal• Globe• Lacrimal gland
- Bony cavity , the globe, muscle cone,optic
nerve-sheath complex,lacrimal apparatus,orbital
fat,vascular and nerve structures,orbital septum
and lids
Orbital Anatomy :
Muscle Cone :- Superior,medial,lateral and inferior recti,Superior
and inferior obliques, Levator palpebrae superioris.
- Introconal space : Surgical problems
- Extraconal space : Medical management
- Globe : Cornea,lens,anterior chamber,vitreous,
retinal - scleral complex
Optic nerve sheath complex :
- Optic nerve , subarachnoid space , fluid
between dura and nerve , diameter of
complex (4-6mm)
Anatomy of the Orbit
• Intraorbital• ExtraconalConal• Intraconal• Globe
Anatomy of the OrbitCompartimental anatomy
• Intraorbital• Extraconal• Conal• Intraconal• Globe• Lacrimal gland
Supraorbital fissure
Infraorbital fissure and pterygopalatine fossa
Supraorbital fissure
Close relationship to PNS
Variant
Anatomy of the orbit
Muscles
Muscles
Anatomy of the orbit
Close relationship to vascular/nerval structures!!!
Orbita may be easily affected!!!
Anatomic regions
Fossapterygopalatina• Close relation
Orbit-PNS-Oropharynx
• Nerves III, IV, V, VI, VII
• Parasellarregion
Maxillary nerve Greater petrosal nerve
Pathology
• Inflammation orbital-extraorbital• Blastoma orbital-extraorbital
benign-malignant• Trauma• Foreign bodies•
Cave metallic foreign bodies NO MRI !!!
Inflammation
Inflammation of lidCT (Abscess)MRI (Phlegmone)
– Spread of infection from
ethmoid cells– Compression of optic nerve– Thrombosis
Harnsberger R:Head and Neck 2004
Subperiostal abscess CT
-Spread of infection from ethmoid cells
-Compression of optic nerve!!
-Thrombosis!!
Harnsberger R:Head and Neck 2004
Subperiostalabscess MRI
Dacryoadenitis
ORBITAL CELLULITIS IN A 13-YEAR-OLD BOY WITH EXTENSIVE RIGHT ETHMOID SINUS DISEASE
The inflammation involved the medial extraconal portions of the right orbitAxial CT scan shows lateral
displacementof the medial rectus muscle and infiltration ofthe extraconal fat (arrows)
Subperiosteal abscess in a 4-year-old girl with chronic right
ethmoid sinusitis
The inflammation involved the preseptal andextraconal portions of the medial right orbit. Axial CT scan shows the slightly displaced and thickened medial rectus muscle and a small focal fluid collection (arrow), which was confirmed as representing a subperiostealabscess
Orbital pseudotumor
Gross mass-like enlargement of the medial rectus muscle, with characteristic hypointense signal on T1W (a) and T2W (b) sequences. Moderate
heterogeneous enhancement is seen in the post gadolinium image (c)
Orbital pseudotumor (different patients)
Axial CECT shows a diffuse infiltrative right orbital mass involving the globe and causing marked proptosis
Diffuse enlargement of the lacrimal gland is seen with preservation of its shape
There is diffuse thickening of the bilateral medial and lateral rectus muscles including their tendinous insertion (arrows) which is typically spared in thyroid ophthalmopathy
Optic nerve neuritis (MS)
3T Orbital pseudotumorNo diffuse infiltration
Pseudo-inflammation
Endocrine orbitopathy CT
Graves disease / M. Basedow
Endocrine orbitopathy MR
Graves disease / M. Basedow
Endocrine orbitopathy 3T MRThickening and hyperintensity of medial and inferior rectus muscle
Small capillary hemangioma
3T MRLarge capillary hemangioma
Hemangiomatosis
3T MRLarge lymphatic-venousmalformation
LYMPHANGIOMA IN A 4-YEAR-OLD BOY WITH SUDDEN SUPRAORBITAL FULLNESS OF THE RIGHT EYE
Axial CT scan reveals a multilocular intraconal lymphangioma in the right orbit.
Lymphangioma in a patient who experienced sudden proptosis and
discolorationabout his right eye
Axial T2/W MR image demonstrates hemorrhage into a multilocular lymphangioma.The high-signal-intensity methemoglobin is layering anteriorly in each cyst.
VENOLYMPHATIC MALFORMATION
USG reveals a multiseptate cystic mass in the orbit MRI reveals a heterogeneous intraconal mass in the right orbit
displacing the optic nerve. Lesion is heterogeneous in signal intensity with a hyperintense area on T1W image (a) which shows blood-fluid level on T2W sequence (arrows) (b). There is only mild enhancement following contrast administration (c)
Blastoma/Tumor-like Bone
Lacrimal gland
Conus
(Globe)
Nerve
Fibrous dysplasia, Metastasis
Adenoma, Dermoid,pleomorphic Adenoma,Lymphoma
Grave`s, Hemangioma,Lymphoma, Schwannoma,Pseudotu
(Melanoma, Retinoblastoma)
Glioma, Meningeoma
P. Som Head and Neck Imaging 4th ed. 2003
Orbital pathologyPathology bony orbit
Fibrous dysplasia orbit
Blastoma
Melanoma lower lid
Dermoid
Fat
3T MRPleomorphic adenoma
Pleomorphic carcinoma with papilla infiltration (II)
Pleomorphic adenomaparotid gland
MALT-lymphoma lacrimal gland
Orbital lymphoma diffuse infiltration
Rhabdomyosarcoma
3T MRRhabdomyosarcomaM. rectus superior
Rhabdomyosarcoma
Cavernoushemangioma
Axial T1W and T2W MRI reveal an elongated lesion around the optic nerve which is hypointense on T1W and hyperintense on T2W sequence. Note the characteristic “club like” configuration of the lesion in the sagittal T2W
Orbital varix
Orbit Varix :
- Large , tortuous vein or a mass like confluence of
small veins may markedly enlarge with changes in
venous pressure (Valsalva ` maneuver)
ORBITAL VARIX
Axial CECT in a child with intermittent proptosis is almost normal. However, during valsalva maneuver the enhancing mass and the associated tortuous venous channels stand out causing significant proptosis
CAPILLARY HEMANGIOMAIN A 5-MONTH-OLD GIRL WITH DIFFUSELY DILATED CAPILLARIES AND CHEMOSIS OF THE EYELID
• Axial and sagittal Ti-weighted MR images demonstrate a capillary hemangioma superficially and preseptally about the left orbit.
• Several prominent vessels are noted within the mass.
CAPILLARY HEMANGIOMA
Axial CECT shows an intensely enhancing mass in the eyelid and extraconal space of the left orbit causing displacement of the globe
CAVERNOUS HEMANGIOMA IN A 16-YEAR OLD BOY
SAGITTAL T1/W MR IMAGE DEMONSTRATES AN INTRACONAL CAVERNOUS HEMANGIOMA POSTERIORLY(ARROW). CAVERNOUS HEMANGIOMAS MAY BE DIFFERENTIATED FROM LYMPHANGIOMA BECAUSE THEY ENHANCE GREATLY AFTER CONTRAST MATERIAL IS ADMINISTERED.
CAVERNOUS HEMANGIOMA
A homogenous well-defined intraconal mass is seen in the left orbit which is isointense on T1W , hyperintense on T2W sequence and reveals heterogeneous enhancement.
Cavernous hemangiomas are not uncommon in children
Optic nerve meningeoma
Tram-track
Glioma II
3T MRGlioma II
LEFT ORBITAL PLEXIFORM NEUROFIBROMA IN A 10-MONTH-OLD BOY
Axial proton-weighted (a) and coronal Ti-weighted (b) MR images demonstrate extensive involvement of the left eyelid and extraconal region by a plexiform neurofibroma
Optic nerve gliomas
in a teenage girl with neurofibromatosis
Axial Ti-weighted (a) and T2-weighted (b) MR images show diffuse bilateral enlargement ofthe optic nerves by gliomas (arrows)
NF-1
Radiograph of the orbit (a) reveals the characteristic enlarged and “bare” left orbit in a child with NF1
Axial CECT shows the dysplastic left greater wing of sphenoid with anterior herniation of the temporal lobe and an ill-defined infiltrative mass in the temporal fossa invading the orbit suggestive of a plexiform neurofibroma
Multifocal meningioma in an 18-year-old male adolescent with
neurofibromatosis
Axial CT scan shows a calcified meningioma of the right optic nerve
Coronal T1/W MR image demonstrates bilateral isointense intraventricular meningiomas
BILATERAL OPTIC NERVE MENINGIOMAS IN A 15-YEAR-OLD GIRL WITH NO OTHER FINDINGS OF NEUROFIBROMATOSIS
Axial CT scan reveals bilateral calcified meningiomas ofthe optic sheath
Optic nerve glioma in a young boy without neurofibromatosis
Axial CT scan shows diffuse involvement of the right optic nerve by a glioma. Pediatric optic nerve gliomas are frequently associated with neurofibromatosis
Schwannoma III
Extraorbital pathology
Schwannoma V2 with elevationof rectus inf. muscle
Angiofibroma with orbital infiltration
SCC
TRAUMA CT
Le Fort II
Orbital floor-fx with herniation of fat
Hematoma
Orbital floor fracture, Motility disturbance
Foreign bodiesNo MRI metallic !!!
Foreign bodies extraconal intraorbital
Foreign bodies
Foreign body sclera
Foreign bodies
Perforatingintraocular fb
Take home points
• Remind anatomic situation• Imaging technique and characteristics and
localisation of pathology (intraorbital compartments)
• Involvement of adjacent structures• Careful analysis DIAGNOSIS
Intraocular disorders
Calcified retinoblastoma
Axial CT scan demonstrates a calcified mass in the left globe, accompanied by some increased attenuation of the vitreous.
Bilateral retinoblastoma
Coronal CT scan and T1-w axial MR image demonstrate bilateral calcified retinoblastomas
The increased signal intensity of the right globe is likely secondary to hemorrhage
The calcifications so prominent on the CT scan are poorly visualized on the MR image
Trilateral retinoblastoma
AXIAL CECT SHOWS BILATERAL INTRAOCULAR MASSES WITH CALCIFICATION
WITH A SEPARATE INTENSELY ENHANCING MASS IN THE PINEAL LOCATION
Medulloepithelioma
Persistent hyperplastic primary vitreous ( PHPV )in a 3-year-old boy
Axial contrast material-enhanced CT scan shows a coneshaped, noncalcified, central retrolental area of increased attenuation in the right eye
Coronal T2/W MR image better depicts this abnormality. The increased signal intensity in the right globe is due to hemorrhage
PHPV
Transverse color Doppler USG shows an echogenic retrolental structure with a vascular channel within, suggestive of PHPV
RETROLENTAL FIBROPLASIA WITH BILATERAL MEDIAL RETINAL DETACHMENTS IN AN 1 1-MONTH-OLD GIRL WITH BILATERAL LEUKOKORIA
The infant, born prematurely, had received oxygen therapy for respiratory distress syndrome. Axial CT scan clearly shows the high-attenuation detached retinas (arrows).
Sclerosing endophthalmitis
Axial CT scan shows a uniform increased attenuation throughout the right globe. The linear area of high attenuation seen in the middle to lateral aspects of the globe is a detached retina. A classic nematode infection was confirmed at the histopathologic analysis. The lack of a focal mass and of calcification helps differentiate sclerosing endophthalmitis from retinoblastoma.
Coat’s disease
Color doppler USG shows a large retinal detachment with hypoechoic subretinal exudates
CT shows diffuse increase in the intraocular density
Orbital rhabdomyosarcoma in a young child
A large superior right orbital mass compressed and displaced the globe anteriorly and inferiorly. The mass is hypointense on the coronal T1/W image and hyperintense on the T2/W image
Orbital rhabdomyosarcoma
Axial CECT show a homogeneous multicompartmental soft tissue density mass causing orbital expansion and destruction of the medial orbital wall
Dermoid and Epidermoid cyst (different patients)
Axial CECT : A well-defined fat-containing lesion is seen near the outer canthus
Axial CECT : The large well-circumscribed cystic lesion at the inner canthus is suggestive of an epidermoid cyst. The adjacent bone is remodelled
Leukemic involvement of the orbit in a 6-month-old boy with acute lymphocytic leukemia
Axial CT scan shows preseptal swellingand involvement the left orbit, diffusescleral thickening with enhancement, and apoorly defined intraconal mass that envelopsthe optic nerve. There is resultant proptosis.
NEUROBLASTOMA IN A 14-YEAR-OLD BOY
Axial CT scan reveals diffuse sclerotic bone involvement from metastatic neuroblastoma. In addition, there is extraconal involvement about the right orbit with resultant proptosis.
Midline granuloma
Coronal CT scan demonstrates a midline mass with encroachment into the left orbit.
Langerhan’s cell histiocytosis
Axial CECT shows destruction of lateral orbital walls and the greater wing of the sphenoid bone on both sides with associated complex soft tissue mass encroaching on the orbits.
The skull radiograph in the same patient reveals multiple well-defined lytic lesions in the cranial vault with typical bevelled edges
Langerhans ‘cell Histiocytosis
( Orbital LCH )
1953 Lichtenstein
Bone or bone marrow lesions ( Overall incidence 23% )
Most commonly in frontal bone ( superior or superolateral wall
of orbit )
- An osteolytic lesion or multiple lesions
- Well defined or diffuse soft tissue mass , encroaching
lacrimal gland , lateral rectus or even the globe
CT and MRI findings :
Differential diagnosis :
- Rhabdomyosarcoma
- Juvenile fibrosarcoma
- Aggressive fibromatosis
- Lacrimal gland tumor
- Leukemic infiltration
- Metastasis ( Neuroblastoma , Wilm's , Ewing's)
Bilateral Anophthalmia
MICROPHTHALMOS IN A 13-YEAR-OLD BOY
CT scan shows the small right globe
The presence of the radiopaque lens differentiates microphthalmos from an orbital cyst
Sagittal T1/W MR image reveals a small cyst adjacent to the insertion of the optic nerve (arrow)
Microphthalmos and persistent hyperplastic primary vitreous (PHPV) are also present
Posterior optic coloboma in a 2-year-old girl with
seizures
Bilateral coloboma
Axial CECT shows defect of the right globe at the optic nerve head via which the vitreous projects posteriorly (arrow). The
left globe is small, with a retrobulbar (colobomatous) cyst (arrow) and dystrophic calcification at the site of coloboma
Duplication cyst
Congenital cystic eye
Axial CECT shows a large right orbital cyst with absence of the globe. Also note the microphthalmia with coloboma and dysplastic lens on the left side
Septo-optic dysplasia in a 22-month-old deaf, mute, and blind boy
Sagittal midline T1/W MR image demonstrates agenesis of the corpus callosum and a prominent anterior inferior recess ofthe third ventricle (arrow).
Axial T1/W MR image shows bilaterally small globes (left larger than the right), with hemorrhage in the left globe. Since no trauma had occurred, the presence of hemorrhage may indicate PHPV is present
Septo - optic dysplasia :
- A part of a spectrum of developmental and congenital brain
abnormalities
- Absence of the septum pellucidum and pituitary -
hypothalamic endocrine dysfunction and hypoplasia of the
optic nerves
Trigonocephalysecondary to metopic suture synostosis
Axial CT scan obtained at the level of the orbit roofs demonstrates a marked frontal and rbital asymmetry secondary to cranial synostosis
Apert syndrome in a 3-week-old boy
Anterior radiograph of the skull demonstrates the typical features ofApert syndrome
Axial CT scan demonstrates the proptosis and shallow orbits
Orbital encephalocele in a newborn
Axial CT scan demonstrates an encephalocele protruding throughthe left orbit. A left globe was not seen, although retinal remnants were found within the encephalocele atautopsy
Coronal CT scan demonstrates a prominent encephalocele that hasballooned inferiorly into the nasal cavity and medially into both orbits (arrows).
Metastatic disease :
- Most common primary tumor is breast , then lung
- In any part of the orbit , bone or soft tissue
- Findings may be subtle , with small focal areas
of thickening of the globe to large destructive lesion