Lecture 33: Eye Flashcards
- levator palpebrae superioris muscle
2.tarsal plate
3.cornea
4.conjunctiva
what is inner surface of eyelids lined with
conjunctivate. specialized mucous membrane. note: doesn;t cover cornea
tarsal plate
2 in image
cartilage forming the skeleton of eyelid.
provides insertion point for levator palpebrae superioris
sebaceous glands embedded in plates
levator palpebrae superioris nerve supply
CNIII and sympathetic fibres
cornea
anterior transparent part eyeball
- ciliary body
2.suspensory lig - pupil
4.cornea
5.iris
what are the 3 layers of eyeball from outside to inside
- Fibrous layer: made of fibrous tissue. Most of posterior part of fibrous layer (5/6) is made of dense irregular connective tissue = sclera. This layer is there to mechanically protect eyeball. Attachment site for E.O. muscles
* Anterior 1/6 of fibrous layer turns into clear/transparent layer=cornea. Clear due to Due to arrangement collagen fibres AND no blood vessel flowing into it- Vascular layer: posterior 5/6 is called choroid. Brings blood vessels to nourish retina
- Anteriorly divides into:
§ Ciliary body: made of smooth muscle fibres.
□ Attached to lens by suspensory ligaments- hold lens in place and change convexity of lens
§ Iris: made of smooth muscle fibres.
□ At center of iris= pupil
□ Fxn iris= expand or reduce size of pupil
- Anteriorly divides into:
- Nervous layer: posterior 3/4 is called retina. Loaded with photoreceptors convert light to nerve impulses
- Anterior 1/4 is pigmented epithelium. Covers ciliary body. Lines posterior surface iris.
§ Determines colour of eye
§ No pigment= blue eyes
Optic nerve (CNII) axons retina
- Anterior 1/4 is pigmented epithelium. Covers ciliary body. Lines posterior surface iris.
- Vascular layer: posterior 5/6 is called choroid. Brings blood vessels to nourish retina
fibrous layer of eyeball
- Fibrous layer: made of fibrous tissue. Most of posterior part of fibrous layer (5/6) is made of dense irregular connective tissue = sclera. This layer is there to mechanically protect eyeball. Attachment site for E.O. muscles
* Anterior 1/6 of fibrous layer turns into clear/transparent layer=cornea. Clear due to Due to arrangement collagen fibres AND no blood vessel flowing into it
vascular layer eyeball
=middle layer
- Vascular layer: posterior 5/6 is called choroid. Brings blood vessels to nourish retina
* Anteriorly divides into:
§ Ciliary body: made of smooth muscle fibres.
□ Attached to lens by suspensory ligaments- hold lens in place and change convexity of lens
§ Iris: made of smooth muscle fibres.
□ At center of iris= pupil
□ Fxn iris= expand or reduce size of pupil
nervous layer eyeball
=inner
- Nervous layer: posterior 3/4 is called retina. Loaded with photoreceptors convert light to nerve impulses
* Anterior 1/4 is pigmented epithelium. Covers ciliary body. Lines posterior surface iris.
§ Determines colour of eye
§ No pigment= blue eyes
Optic nerve (CNII) axons retina
is pupil dilated by symp or para?
symp! maximized light entry into eye
- macula lutea
- optic disk
- fovea centralis
blind spot
=optic disk
no PRs
macula lutea
“yellow spot”
at centre is fovea centralis- higest [PRs]
blood supply eye
choroid
what happens to lens when looking at near object
lens is super convex.
ciliary body contracts
suspensory ligaments are loose
PSN