Monday, March 16, 2015

Extraocular Muscles Function and Innervation

Eye Movement Control Systems

Extraocular Muscles : Function

Superior Oblique muscle : can depress and abduct the eye from the neutral position. From the adducted position, it is the only muscle that can depress the eye

Inferior Oblique muscle : can elevate and abduct the eye from the neutral position.From the adducted position, it is the only muscle that can elevate the eye

Superior rectus muscle : can elevate and adduct the eye from neutral position. it is the only muscle that can elevate the eye from the abducted position

Inferior rectus muscle : can depress and adduct the eye from the neutral position. From the abducted position , it is the only muscle that can depress the eye.

The Lateral rectus muscle can abduct the eye.


Innervation:

Cranial Nerve III :

  • Medial rectus : adducts eye
  • Superior rectus : elevate, intorts, adducts eye
  • Inferior rectus  : depresses, extorts, adducts eye
  • Inferior Oblique: elevates, extorts, abducts eye

Cranial Nerve IV : 

  • Superior Oblique : depresses, intorts , abducts eye
Cranial Nerve VI : 

  • Lateral rectus: Abducts eye.