Flashcards in BCSC Plastics Deck (238)
Are capillary hemangiomas in children benign or malignant?
Benign, but may cause mass effect
When do capillary hemangiomas usually present?
birth to first few weeks of life, enlarging over first 6-12 months
What percent of capillary hemangiomas resolve within the first 4-5 years of life?
Is CVS a risk factor for capillary hemangioma?
How can MRI be used to distinguish capillary hemangiomas from other vascular malformations?
MRI will show fine vascular channels and high blood flow
What part of the orbit do capillary hemangiomas have a propensity for?
What are the major complications of capillary hemangiomas?
Amblyopia, strabismus, and anisometropia
What are possible treatments for capillary hemangiomas?
topical or systemic beta blockers, steroids, surgical excision
What is the most common benign neoplasm of the orbit in adults?
What is the histology of the cavernous hemangioma?
The lesions are encapsulated and composed of large cavernous spaces containing RBCs. The walls contain smooth muscle
Are arteriography and venography useful in evaluation of cavernous hemangiomas?
No, there is little communication with the systemic circulation
What is the management of cavernous hemangioma?
Surgical excision after imaging if there is compromise of ocular function
Are hemangioperictyomas common?
What is the histology of the hemangiopericytoma?
Plump pericytes surround a rich capillary network
When do lymphatic malformations (lymphangiomas) generally present?
Within the first decade of life in the orbit
What is the histology of the lymphatic malformation?
They generally contain both lymphatic and venous components and are characterized by large, serum-filled channels that are lined by flat endothelial cells
Are lymphatic malformations technically neoplasms?
No, because their endothelial cells do not proliferate
What are the features of lymphatic malformations on MRI?
multiple grape-like cystic lesions with fluid-fluid layering of the serum and red blood cells
How can a venous malformation be diagnosed?
With demonstration of engorgement on spiral CT during a Valsalva maneuver (decreasing venous return)
What is the management oforbital venous malformations?
Conservative, with surgical excision only if there is vision-threatening compressive optic neuropathy; embolization with coils may also be employed
What are arteriovenous fistulas?
acquired lesions caused by abnormal direct communication between an artery and a vein
What are the possible causes of an AV fistula?
Trauma or degeneration
What are the 2 forms of AV fistula?
Carotid cavernous fistula (typically occurs after a basal skull fracture) and Spontaneous Dural Cavernous Fistula (degenerative process in older pts with HTN and atherosclerosis)
Do carotid cavernous fistulas have high blood flow?
What are findings associated with carotid cavernous fistula?
Tortuous epibulbar vessels, audible bruit, pulsatile proptosis
How does a carotid cavernous fistula cause damage?
Bypass of the capillary network results in ocular ischemia; Direct passage of blood into the venous system results in venous outflow obstruction --> increased IOP, choroidal effusions, blood in Schlemm canal, nongranulomatous iritis, increased cavernous sinus pressure leading to CN III, IV, and VI palsies
How do Dural Cavernous Fistulas occur?
small meningeal arterial branches communicate with venous drainage
How does chronic red eye occur in Dural Cavernous Fistula?
Arterialization of the conjunctival vessels
How is embolization of AV fistulas usually accomplished?
endovascular transarterial route