Test 4: Eye Flashcards
(45 cards)
Duct System
Runs under eyelid
produces tears
Lacrimal Punctum
Drains into lacrimal sac
Nasolacrimal Duct
Drains into inferior meatus of nasal cavity
Orbital Axis
23 degrees from midline/optic or visual axis
-can align orbital and optic axis but only one eye at a time
Tear Pathway
1) Duct System
2) Lacrimal Punctum
3) Lacrimal Canaliculus
4) Lacrimal Sac
5) Nasolacrimal Duct
6) Inferior Meatus in Nasal Cavity
7) Sinuses
8) Swallowed
Optic Canal
Optic Nerve (CN2) and ophthalmic artery goes through
Superior Orbital Fissure
1) Contains nerves and vessels other than optic nerve and ophthalmic artery
- supply face and orbit
2) Nerves/vessels–>Supraorbital Notch–>Forehead
Inferior Orbital Fissure
1) Continous
- posteriorly w/ ptergyopalatine fossa
- inferiorly w/ infra temporal fossa
2) Maxillary Division of Trigeminal Nerve (CN5) runs through the floor
- part passes through infraorbital sulcus–>Infraorbital foramen–>Face
Orbit
1) Protected Laterally by frontal and zygomatic bones
Para Nasal Sinuses
1) Separated from orbit by thin plates of bone
Orbicularis Oculi Muscle
1) Encircles the eye and in eyelid
2) Open/closes eye
Tarsal Plates
1) Superior & Inferior
2) Protective Function
- Contain Meibomian Glands (AKA tarsal glands)-secrete oily substance/lipids that lubricates the lid margins so eyelids don’t stick together
- prevents tears from overflowing onto the face
Conjuctiva
1) Thin translucent mucous membrane
2) Palpebral Conjuctiva
- lines inner surface of eyelids
- reflected at fornices (superior and inferior)
- attached to tarsal plates
- vascular
3) Ocular Conjuctiva
- loosely attached to sclera
- Translucent & Avascular so sclera is visible
- over cornea- only consists of epithelium layer
Conjucvitis
1) AKA pink eye
2) inflammation of conductive
3) Bacterial
- Treatable w/ antibiotics and steroids
4) Viral
- Has to run its course
- Tx: Steroid
Bulbar Fascia
1) AKA Tenon’s Capsule
2) Thin fibrous capsule that convers eye
- optic nerve (posterior) to corneal-scleral junction (Anterior)
- anchors eye to CT
3) Pierced by tendons of extra ocular Muscles
- forms sheath around muscle
Superior Tarsal Muscle
1) Smooth Muscle
2) Under control of sympathetics
- K/0=relax->Drooping eyelid=PTOSIS (Horners Syndrome)
Levator Papebrae Superioris Muscle
1) Skeletal Muscle
2) Attaches to superior tarsal plate
Medial/Lateral Palpebral Ligament
1) Helps anchor the tarsal plates within orbit
2) Attaches:
- medially to lacrimal and maxillary bones
- laterally to zygomatic bones
Extraoccular Muscles
1) Superior Oblique Muscle
2) Inferior Oblique Muscle
3) Levator Palpebrae Superioris Muscle
4) Superior Rectus Muscle
5) Medial Rectus Muscle
6) Inferior Rectus Muscle
7) Lateral Rectus Muscle
8) Pulley (Trochlea)
- idk if this is muscle
Superior Oblique Muscle
1) Extraocular Muscle
2) Innervates lateral side of eye
3) loops through Pulley (Trochlea)
4) Contracts- rotate eye
Inferior Oblique Muscle
1) Extraocular Muscle
2) Innervates Lateral Side of eye
3) Contracts-rotate eye
Tunics of eye
1) External Fibrous Tunic
- Cornea & Sclera
2) Middle Vascular Tunic
- Choroid, Ciliary Body, Iris
3) Internal Nervous Tunic
- Retina
Lens
1) Biconvex Disc
2_ Bends light as it passes through
3) 1 cm diameter
4) Enclosed in capsule
5) Attached to ciliary body by suspensory ligaments (AKA zonular Fibers)
-contraction of ciliary musculature (Parasympathetic)=relax suspensory ligaments
-becomes more convex (Round)
-resutls in more refractive power for near vision
6) Accommodation
-altering the convexity/shape of lens to bring object into focus
Accommodation
1) Alter the convexity/shape of lens to bring object into focus