Disorders 1 Flashcards
dermoid cyst (choristoma)
arises from dermal elements (neural crest)
MC orbital mass in childhood
lined by keratinizing dpi with dermal appendages
usually near SUPEROTEMPORAL quad
can lead to bony erosion and rupture can lead to severe inflammation
CT: well circumscribed with bony molding
TX: remove, en bloc
Epidermoid Cyst
ONLY epidermis, NO dermal appendages
filled with keratin
rupture = acute inflammatory process
Lipodermoid
solid tumor, beneath conj over lateral surface of glove
hard to excise; can look like prolapsed orbital fat, prolapsed lacrimal gland or lymphoma
Teratoma
rare, cystic tumor arises from >2 germinal layers (ectoderm + endoderm and/or mesoderm)
capilalry hemangioma
MC benign tumor
starts first few weeks of life, increases over first 6-12 months, regression by 5-8 yo
superior nasal quadrant of orbit and medial upper eyelid
F > M
diffuse unencapsulated irregular mass of plump endothelial cells/small vascular channels
s/s: strawberry nevus, when in orbit can look blue and with proptosis
CT: well circumscribed lesion
TX: obs, propanolol
Complications: high output CHF with multiple hemangiomas; respiratory compromise with subglottic ones
strabismus/amblyopia
Kassabach- Merrit syndrome
consumptive coagulopathy, platelet trapping, leads to thrombocytopenia and cardiac failure; 30% mortality
unencapsulated cysts
capillary hemangioma
lymphangioma
lymphangioma
rare, lymphatic filled choristoma
superonasal
eyelids, conj, deeper orbital tissues
waxes and wanes; does NOT involute
acute pain, proptosis, bluish hue to overlying lid, can hemorrhage into channels (chocolate cyst)
path: lymph filled vascular channels lined with endothelium
CT/MRI: infiltrative pattern
TX: obs, rarely surgical b/c hard to completely excise and can recur
Albright Syndrome
polyostotic fibrous dysplasia (multiple bones involved); short stature, premature closure of epiphyssis, precocious puberty, hyperpigmented macules
cavernous hemangioma
MC benign tumor in adults
slow porgressive proptosis
can induce hyperopia
CT: well demarcated, ENCAPSULATED intraconal mass
path: lesion filled with flood filled cavernous spaces, lined by endothelial cells
MRI: hypointense to fat on T1 weighted images, hyperintense to fat and equivalent to vitreous on T2 weighted images
hemangiopericytoma
rare tumor, abnl pericytes surround blood vessels
middle aged women
can METASTASIZE to lung, bone, and liver
slowly progressive proptosis, can be painful
CT: well circumscribed, encapsulated mass
Tx: COMPLETE removal
Schwannoma
encapulated
no malignant potential
can be painful
superior orbit
can grow along ANY peripheral or cranial nerve (MC = CN 8)
rarely associated with NF
path: S-100 stain (stains everything of neural crest origin)
Antoni A: spindle cells arranged in interlacing cords, whorls, or palisades, have verocay bodies
Antoni B: loose, myxoid, stellatTe cells with a mucoid stroma
CT: well circumscribed, fusiform mass
TX: complete surgical excision, can recur
optic nerve sheath meningioma
MC women
increased incidence in NF paitnets
from arachnoid cells in meninges
have decreased VA/color vision, visual field loss, proptosis, disc edema or pallor
path: sheets of cells or whorls, psammoma bodies (calcified) in the center
CT: tram track enhancement
TX: obs, surgery to prevent involvement of optic nerve/chiasm
spencer’s triad
optociliary shunts, optic atrophy, optic nerve mengioma
sphenoid wing meningioma
MC tumor to spread to orbit from intracranial spac
s/s: temporal fullness, proptosis, lid edema
CT: hyperostosis/calcification
Tx: obs/excise
Lymphoid tumor
abnl proliferation of lymphoid tissue make up 20% of all orbital tumors 90% are non Hodgkins B-cell are conjunctival/lacrimal gland lesions painLESS proptosis MUST have workup for systemic lymphoma