Lecture 17 - The Eye Flashcards
List the 7 bones of the orbit
- Frontal
- Ethmoid
- Lacrimal
- Maxilla
- Sphenoid
- Zygomatic
- Palatine
What is the area between the superior and inferior palpebrae (eyelids)?
Palpebral Fissure
Point where the upper and lower palpebrae meet
Lateral canthus and medial canthus
Small, fleshy, or glandular area medial of the eye
Lacrimal caruncle
Function of levator palpebrae superioris
Elevates and retracts the eyelid position, maintain eyelid position
What are the functions of lacrimal fluid? (2)
- Lubricates the eye surface
- Removes debris
List the 4 rectus muscles and their innervation
- Superior Rectus - CN III
- Inferior Rectus - CN III
- Lateral Rectus - CN VI
- Medial Rectus - CN III
List the two oblique muscles, their innervation, and action
- Superior Oblique - CN IV, elevate and abduct
- Inferior Oblique - CN III, depress and abduct
What are the three main layers of the eye ball
- Outer fibrous layer
- Middle vascular layer
- Inner neural layer
Components of the outer fibrous layer
- Cornea: Transparent layer that refracts light entering the eye
- Sclera: White outer layer, attachment site for extraocular muscles
Components of the middle vascular layer
- Iris: Coloured part of the eye, controls pupil size
- Ciliary Body: Produces aqueous humour and controls lens thickness
- Choroid: Layer of tissue and blood vessels that nourish the retina
Components of the inner neural layer
- Retina: Layer of photoreceptor cells that convert light to electric signals, send to brain via CN II
List the borders of the anterior cavity of the eye
- Cornea and lens
☆ lens divides the two cavities
List the borders of the anterior and posterior chambers of the anterior cavity of the eye
- Anterior Chamber - Between cornea and iris
- Posterior Chamber - Between iris and lens
Explain the concept of lens accomodation
Closer objects -> Lens thickens
Farther objects -> Lens flattens
☆Controlled by ciliary body
