Extraocular Muscle Actions & Clinical Testing
What about clinical testing of extraocular muscle function & associated nerve integrity?
Adduction (~51°), produced by the medial rectus, aligns the optical axis with the line of pull for the superior & inferior obliques muscles. In this position...
 - only the inferior oblique produces elevation 
 - only the superior oblique produces depression
Abduction (~23°), produced by the lateral rectus, aligns the optica axis with the line of pull for the superior & inferior rectus muscles. In this position...
 - only the superior rectus produces elevation
 - only the inferior rectus produces depression
Nerve Palsies:
 • CN Ill: ptosis, mydriasis, eye position "down & out"
 • CN IV: vertical or torsional diplopia
 • CN VI: inability to abduct eye

by Mikaela Stiver @MikaelaStiver

#Extraocular #Muscle #Actions #diagnosis #testing #ophthalmology