Originally Posted by rj23
According to wikipedia, damage to trochlear nerve causes weakness of the downward eye movement and subsequent double vision. the affected eye drifts upward relative to the normal eye. According to uworld it says the affected eye is looking towards the nose. which causes double vision. In reality damage to the trochlear nerve causes down and out movement of eye.
Question was a patient is suffering double vision while walking down the stairs. which nerve is damaged.
Can anybody explain what is this.
Trochlear supplies the superior oblique and the main action of this muscle is INTORSION,
next it also causes DEPRESSION in the ADDUCTED position
. So to test it you would ask the patient to look medially and down. The lesion of this muscle causes extorsion. Thats why when you will have trouble going down/reading and head with will be tilted away from the lesion side to fix extorsion.