Orbits Flashcards
Modality used to evaluate orbits
CT scan
Space defined as being outside the cone formed by the extraocular muscles
Extraconal space
Space defined as being inside the cone formed by the extraocular muscles
Intraconal space
Retinoblastoma is clinically presented as?
Leukokoria
Most common tumor of globe in childhood
Retinoblastoma
Most common cause of orbital calcification
Intraocular mass with calcifications
Types of retinablastoma based on number globes affected with other sites affected
Unilateral -75%
Bilateral -25%
Trilateral= bilateral + pinealoma
Quadrilateral= bilateral + pinealoma + 4th focus in suprasellar cistern
It is typical for retinablastoma
Orbital calcification
Primary orbital bone tumor that makes up 0.6-2.0% of all tumors of the orbit
Osteosarcoma of the orbit
It is an example of extraconal lesion
Osteosarcoma of the orbit
This can be seen on CT scan associated with aggressively occurring lesion
Sunburst appearance
Also known as end-stage eye. It is usually a result of several ocular insults
Phthisis bulbi
In the elderly population, phthisis bulbi is the most common cause of what?
Intraocular calcification
It drains blood from the superior and inferior ophthalmic veins
Cavernous sinus
Cavernous sinus is connected to the transverse sinus by what sinus?
Superior petrosal sinus
Cavernous sinus is connected to the jugular bulb by what sinus?
Inferior petrosal sinus
Pressure in the cavernous sinus is?
0mmHg
It is a fistulous connection between the internal carotid artery and cavernous sinus. This is most commonly secondary to trauma resulting to tear in the artery.
Caroticocavernous fistula
Pathogenesis of caroticocavernous fistula
Abnormal flow from the high pressure internal carotid artery onto the low pressure cavernous sinus. Because of increased pressure in the sinus, there is a REVERSAL of flow in the OPHTHALMIC VEINS, predominantly in the SUPERIOR OPHTHALMIC VEIN (resulting to proptosis and other clinical symptoms).
What is Huber’s maneuver?
Vertebral angiogram + carotid artery compression
Tool used in conjunction with coil embolization
Sapphire angioplasty balloon
Coil used in embolization
Guglielmi detachable coil
