LETS LEARN!

assalamualaikumwarahmatullah dan selamat sejahtera

picture 1: This is the picture of our eye with the muscle

as we all know, we have 6 ocular muscle

1. lateral rectus
2. medial rectus
3. superior rectus
4. inferior rectus
5. superior oblique rectus
6. inferior oblique rectus

all recti are innervated by different nerve

LR6 SO4 3

picture 2: The picture is about the action of each muscle

We have 5 basic eye movements which are Saccadic eye movement, Pursuit eye movement, Vergence eye movement, Reflex eye movement and Vestibulo-Ocular movements. 

1. Pursuit movement is the most smooth, slow and tracking movement of the eyes. Pursuit movement occurs under voluntary control only because it has to keep the image on the fovea of different positions. 
2. Saccadic eye movement is the rapid eye movement of the same direction which is conjugate movements. Saccadic movement can be voluntary and involuntary. Saccadic eye movement always used when scanning visual scene or reading. 
3. Examples of vergence eye movement are divergence and convergence. Divergence is used for looking at far object and convergence is always used for looking at near object. Vergence eye movement is disconjugate eye movement which the eyes are moving to the opposite direction. Vergence eye movement can be voluntary and involuntary. 
4. Reflex eye movements can be test by opto-kinetic, caloric stimulation and body rotation. Reflex eye movements will cause nystagmus. 
5. Vestibulo-ocular movements will produce rapid eye movements in the opposite direction of the head movements. Vestibulo-Ocular movements are reflective involuntary.

Action of each muscles

• Lateral rectus and medial rectus will only have primary action which is lateral rectus for abduction and medial rectus for adduction. 
• The primary action of superior rectus is elevation, the secondary action is incyclotortion and the tertiary action is adduction. 
• The primary action of inferior rectus is depression, the secondary action is excyclotortion and the tertiary action is adduction.  
• The primary action of superior oblique is incyclotortion, the secondary action is depression and the tertiary action is abduction. 
• The primary action of inferior oblique is excyclotortion, the secondary action is elevation and the tertiary action is abduction.

from far with love,

firdawaniruz