Dr. Crum the Orbit Flashcards
Imaging options of orbit?
CT MRI US plain films angiography
Plain films
mainly for screening for metallic foreign bodies prior to MRI
Terrible soft tissue detail
would wood or glass react in an MRI machine?
no
Why do we do ultrasound on the globe?
good for lesions or foreign bodies
poor penetration
Do plain films give radiation?
yes, small amounts
Why do we use angiography?
good for vascular malformation and tumors
invasive
time-consuming
Does angiography have radiation exposure?
yes
What is one of the causes of cataracts?
CT scans
What is CT used for?
versatile
excellent bony detail
calcifications
MRI have radiation exposure?
no, metal, pace makers, chlosterphobia
What is MRI good for?
better for optic nerve and tumors
poor temporal resolution
must screen for metallic foreign bodies
Infection: What is difference between periorbital cellulitis and preseptal cellulitis?
Preseptal cellulitis
limited to soft tissues ANTERIOR to the orbital septum
Orbital cellulitis
Postseptal infectious process
most commonly caused by paranasal sinusitis
etc… everything is bad on the list
what is the most common cause of exophthalmos?
autoimmune, lid retraction, proptosis, conjunctivitis
Graves ophthalmopathy
Hallmark of retinal detachment on axial MRI?
V shape appearance on the eye… Retina is infolded
