Occulomotor nerve palsy causes all of the following EXCEPT: (A) Ptosis, (B) Mydriasis, (C) Upward and lateral detion of eyeball, (D) Pupillary reflex lost
Answer is C. Upward & lateral detion of eyeball doesn't happen in oculomotor nerve palsy. Oculomotor nerve (CN III) innervates all EOM except: Superior oblique (CN IV) & lateral rectus (CN VI) Paralysis of CN III results in: Ptosis (due to LPS involvement) Lateral & downward detion of eye (LR & SO are the only muscles intact, unopposed action) Dilatation of pupil (paralysis of sphincter pupilae muscle) Loss of accommodation reflex (paralysis of ciliary muscles)