eye, orbit, and orbital Adnexa

nasocilary nerve branches and innervates

anterior and posterior ethomoidal nerves -- nasal cavity infratorchlear nerve (nasal dorsum and medial upper eyelid and eyeball)

aqueous chamber contains

anterior portion has iris = opens and closes eyelid = muscular diaphragm, iris seperates into anterior and posterior portion

chambers of globe

aqueous and virterous, seperated by lens

ptosis

both levator palprebrae superioris and superior tarsal muscle needed to keep eyes open, if you loose innervation to one = drooping of eyelid

V1 branches

lacrimal, frontal, nasociliary

lacrimal nerve innervates

lateral eyeball (sclera and cornea and upper lid) and lacrimal gland

eyelid elevators

levator palperae superioris superior tarsal muscle

ethmoidal foramina

on frontal bone ethmoidal nerves V1 ( nascociliary nerve) ethomidal arteris (opthalmic art)

blood supply to eye

ophthalmic and internal carotid arts

superior tarsal muscle

underneath levator palprebrae superioris and attached to tarsal plate (smooth muscle) innervated by sympathetic nerves lifts eyelid

bony orbit

7 bones, pear shaped roof: frontal bone floor: maxilla lateral wall: zygoma and greater wing of sphenoid medial wall: lacrimal, ethmoid (lamina papyracea, palatine

lateral rectus

ABduct (CN6)

medial rectus

ADduct

globe is ______ 23 degrees to direct the pupil in straight ahead position

ADducted

superior orbtial fissure

CN 3, 4 and 6 go through here and V1 and opthalmic veins

what's located in the wall of cavernous sinus and whats IN the sinus

CN 3, 4, V1, V2 are in WALL internal carotid and 6 are IN sinus

all sensory info from your cornea and sclear is from

V1 (opthamlic)

sensory nerves in orbit

V1, V2

accomdation

ability to look at infinity and then at 24 inches quickly 1) ADduction of eyeballs 2) miosis by sphincter pupillae (making pupils small) 3) relaztion of suspensory ligament of lens that results in lens rounding

tunic of globe

fibrous = sclera vascular = choroid neural layer = retina

obicularis occuli

closes the eyelid, inserts medially and laterally inervated by facial nerve (7)

basic tears

come from minor tarsal galnds, under the conjucvtiva used under normal conditions, under control of pterygopalantine ganglgion

ciliary muscles

contractoin of parasympathetic III = relaxation of suspensory ligs , lens rounding, near vision involved in accomadation

superior oblique

depress and ABduct (intorsion = med rotation) runs around the trochlea, fibers run posterior to insert on eyeball, inserts in the posterolateral aspect of gloe

inferior rectus

depresses and ADduction

iris contains what smooth muscles

dilar pupillae (sympath) constrictor pupillae (parasym)

inferior oblique

elevate and ABduct (extorision = lat rotation)

mvmts of eye

elevate, depress (up and down) ABduct (lateral) and ADduct (medial) intorsion (medial rotate) and extorsin (lateral rotate) used for focusing

superior rectus

elevates and ADduction occulomotor CN 3

ciliary body

extension of choroid makes and secfetes aqueous humor and drains them controls shape of lens via ciliary muscle

what occupies most of the orbital space?

fat, globe only 20%

lacrimal glands

function under stimulation (emotion or dirt), under control of pterygopalantine ganglgion

macula (fovea centralis)

geometric center of eye, where keen vision is generated

lacrimal gland innervation

greater petrosal branch (7) = preganglionic parasym pteygopaantine ganglgion = synapse then, zygomatic branch of V2 = postgang then to lacrimal gland

optic canal

in lesses wing wphenoid CN 2 comes out here and opthalmic arteries

V2 branches and innervations

infraorbital: skin lower eyelid, alveolar to teeth, upper lip and face zygomatic: skin cheek

inferior orbital fissure

infrorbital nerve (V2) zygomatic nerve (V2) alveolar nerves (V2) infraoritbal vein and art

cornea

modified epithelium convers anterior 1/6 of eye = refractive

levatator palprebrae superioris

most superior muscle in orbit (skeletal muscle) innervated by occulomotor CN III inserts into skin of eyelid lifts eyelid

CN 3 innervation of occulomotor muscles

nerve splits when it gets to rami, supeior ramus innervates the levator palpebrae and superior rectus, while inferior rectus goes to medial and inferior rectus and infrerior oblique

optic disk

neurovascular entrance to eyeball point of exit for ganglion cell axons leaving the eye. Because there are no rods or cones overlying the optic disc, it corresponds to a small physiological blind spot in each eye.

oculomotor parasympathetics

pregang: oculootor gang/synapse: ciliary post gang: short ciliary nerves smooth muslce of eye = constrictor pupillae

glaucoma inceases ---

pressure of aqueous chamber

annulus of Zinn ( tendinous ring)

ring forms origin for 5 of 6 extra oculuar muslce, all except inferior oblique (on maxilla) AND levator palpebrae

eyelid structures

skin conjuctiva (specialized epithelium on external eyelid) grayline conjugated sac orbital septum tarsal plate

tenon's capsule (bulbar fascia)

socket where globe site continuous with extra-ocular muscle fascia helps move prosthetic eyes

all extra occulmotor muscles innervated by CN 3 except

superior oblique (SO4) lateral rectus (LR6)

tear drainage system

superior puncta inferior puncta canaliculi nasolacrimal canal

branches of frontal nerve and innervations

supratrochlear (medial forhead) and supraorbital (lateral forehead)