Flashcards in BCSC Plastics Deck (238)
Are optic nerve gliomas benign or malignant?
They are benign in the first decade of life, but can be malignant if onset is in the adult male
What is the prognosis for malignant optic nerve gliomas?
Very poor -- usually death within 6-12 months even with treatment
What percent of optic nerve gliomas are associated with neurofibromatosis?
What are the clinical findings of optic nerve glioma?
gradual, painless, unilateral axial proptosis associated with loss of vision and an afferent pupillary defect
What is the gross pathology of the optic nerve glioma?
Smooth, fusiform intradural lesion
Where do optic nerve gliomas in patients with NF usually proliferate?
the subarachnoid space
What are the findings of optic nerve glioma on CT or MRI?
fusiform enlargement of the optic nerve with sterotypical kinking of the nerve
What are the possible treatment options for optic nerve glioma?
Observation only, surgical excision, radiation therapy, radiation therapy
Of what are neurofibromas composed?
proliferating Schwann cells within nerve sheaths with occasional axons, endoneural fibroblasts, and mucin
What are the two types of neurofibromas?
PlexiformNeurofibromas and Discrete Neurofibromas
Which type of neurofibroma (plexiform or discrete) is easier to excise surgically?
In which form of neurofibromatosis do plexiform neurofibromas usually occur?
What is the inheritance of NF 1?
autosomal dominant with incomplete penetrance
What are the clinical findings in NF 1?
Plexiform neurofibromas of the lateral aspect of the upper eyelid (S-shaped contour of lid), pulsating proptosis, optic nerve glioma
What are meningiomas?
Invasive tumors arising from the arachnoid villi
What are the findings of meningioma on neuroimaging?
diffuse tubular enlgargement of the optic nerve with contrast enhancement. On CT, calcification may be seen within the meningioma referred to as tram-tracking
What is the most common primary orbital malignancy of childhood?
What is the average age of onset of rhabdomyosarcoma?
What is the common clinical picture of rhabdomyosarcoma?
child with sudden onset, rapidly-progressive unilateral proptosis with discoloration of the eyelids; ptosis and strabismus may also be present
From what do rhabdomyosarcomas arise?
Undifferentiated pluripotential mesenchymal elements of the orbital soft tissues (not from the extraocular muscles)
What are the 4 categories of rhabdomyosarcoma?
Embryonal, Alveolar, Pleomorphic, Botryoid
What is the common management of rhabdomyosarcoma?
Biopsy via anterior orbitotomy, surgical excision if there is a pseudocapsule, chemo and radiation, possible exenteration
What is the most common form of rhabdomyosarcoma?
Which form of rhabdomyosarcoma has the worst prognosis?
Alveolar, 10-year survival rate 10%
Which form of rhabdomyosarcoma has the best prognosis?
Pleomorphic, 97% survival rate
What portion of orbital tumors are lymphoproliferative neoplasms?
What is the most common type of orbital lymphoproliferative disease?
Malignant non-Hodgkin B-cell lymphoma
What percent of orbital lymphomas are MALT lesions?
What percent of patients with orbital MALT will develop systemic disease at 10 years?