Docstoc

Eye

Document Sample
Eye Powered By Docstoc
					Eye

Layers

       1. Connective tissue layer:
             a. Cornea (anterior)
             b. Sclera (posterior)

              Organization – 5 Layers:

                  1.   Epithelium
                  2.   Bowman’s layer
                  3.   Stroma
                  4.   Descement’s membrane
                  5.   Endothelium

              Difference between Cornea and Sclera -> Sclera white – Cornea transparent because the
              collagen fibers in the Cornea are perfectly parallel. The border between the Cornea and
              the Sclera is called Limbus (lat. border)

       2. Vascular layer – Uvea (gr. Grape):
             a. Iris
             b. Ciliary body
             c. Choroid
       3. Neural tissue
             a. Retina
                       i. Rods and cones
                      ii. Bipolar cells – Horizontal cells interdispersed
                     iii. Ganglion cells

Organization:

Anterior Segment:

              1. Anterior Chamber between Cornea and Iris
              2. Posterior Chamber between Iris and ciliary body

Posterior Segment:

          Vitreous chamber with vitreous body/humor (jelly like at birth)

Lens

          1. Capsule
          2. Cortex
          3. Nucleus

          Lens connected to ciliary body by zonulae / zonules

Muscles:

4 Rectus muscles:
        1.   Superior rectus
        2.   Inferior rectus
        3.   Medial rectus
        4.   Lateral rectus

2 oblique muscles:

        1. Superior oblique
        2. Inferior oblique

Origin: All rectus muscles and superior oblique arise from a fibrous ring surrounding the optic nerve
called the Annulus of Zinn. Inferior oblique arises from floor of orbit

Insertion: All insert on the Sclera.

Innervations: All muscles except the Superior oblique and lateral rectus are innervated by the
Oculomotor nerve (CN III) the superior oblique is innervated by Trochlear nerve (CN IV) the Lateral
rectus is innervated by the Abducent nerve (CN VI)

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:3
posted:11/11/2012
language:Unknown
pages:2