- Secreted by lacrimal gland & accessory lacrimal glands

- Supplies oxygen to the cornea

- Antimicrobial function

-Creates smooth optical surface

-washed debris away

-Secreted by Meibomian Glands & Glands of Zeis

-Retards evaporation of aqueous

-Lubricates eyelids

-Lowers surface tension of tear film. Draws water into tear film

-Secreted by Globet cells in conjunctiva

-Converts hydrophoic surface of cornea into a hydrophillic surface for better wet ability

Contains blood vessels called the minor circle of iris

-Contains the Iris Sphincter- Under Parasympathetic control

Two layers of epithelium

-Anterior layers is the dilator muscle: Under Sympathetic Control

Lies behind the lens, contains fibers (Zonules) that hold the lens in place

Aids in the accommodative (near focus) process

Bioconcave avascular transparent structure

Function: allows for accommodation which help focus images closer to observer

Found within the pupil, behind the iris

Gell like substace comprised of collagen fibers & glycoaminoglycans, supported by hyaluronic acid molecules

With aging, reduction in hyaluronic acid causes loss of support to the collagen

*Serves as shock absorber

Nourishes the retina

absorbs excess light that passes through the retina

-Lens loses elasticity

-Accommodative system fail to function

- S&S: decreased vision w/o corrective lenses. Hold objects away and they become clearer, keep in mind they could have near of far problems

Cloudy Vision

Increased IOP

Nausea & Vomiting

Aqueous humor in posterior chamber= pushes iris outward, inhibits outflow

Pupillary block - most common cause

Hyperopia

Medications: mostly sulfa derived

Tumors

Topical alpha agonist

Topical Beta Blockers

Carbonic Anhydrase Inhibitors

Prostaglandin analogs

Miotic agents (parasympathomimetics)

Recheck IOP hourly, Opthal consult STAT

Most common cause of acute reduction in vision because optic nerve dysfunction in 20-40 yo

-Usually affect 1 eye

-Painful rapid vision loss, especially eye movement

-Color vision changes (dyschromatopsia) more than visual

Sudden, Profound, painless, monocular vision loss

Prodrome of episodic amaurosis fugax

Retina -> pale, edematous, transparent

"cherry red spot" area of macula

Central Retinal Artery Occlusion CRAO

Retina: irreversible damage in 90 minutes or less of a total occluded vessel

Painless, loss of vision, monocular, rapid

Fundoscopic: optic disc edema, retinal hemmorrhages in all quadrants

"blood and thunder fundus", Cotton wool spots

Central retinal Vein Occlusion CROV

Causes venous stasis, edema, hemorrhage

-HTN retinopathy, DM retinopathy, leukemic retinopathy, papilledema, Retinopathy of anemia

Evaluation: eye exam, history, tonometry

Aspirin

Photocoagulation

Treat underlying medical disease/causes

Prognosis: variable

Patient focus: monthly check ups x 6 months

Giant Cell (temporal) Arteritis

Signs and Symptoms

Retinal Detachment

Causes: Degeneration (30%) Trauma (5-10%)

Temporary loss of vision in one eye/both eyes due to bloack of blood flow to the retina

"shade" or "curtain" coming down

can happen in seconds

Vitreous Hemmorrhage

blood int he vitreous space

Tx: bedrest, elevate head, avoid asprin

Iritis (AKA anterior uveitis, iridocyclitis)

Most commonly: idiopathic or autoimmune

Corneal Ulcer (AKA infectious keratitis)

Risks: contact lenses, trauma, dry eyes, lid abnorm

Common cause: Psuedomonas a. Staph a.

Staph epid. Strep. pneumo. H.flu M. Catarr

Age related (senile) MOST COMMON

Trauma

Toxic (steriods)

Intraocular Inflammation (uveitis)

Radiation

Intraocular tumor

DM

Hypocalcemia

Degenerative ocular disease (retinitis pigmentosa)

Trauma- Most common cause

Marfan Syndrome

Homocystinuria

Aquired Syphilis

High myopia

Decreased vision

Monocular diplopia

Quivering of iris (iridodonesis)

Quivering of lens (phacodonesis)

Marked astigmatism

AACG

Cataract

Asymmetry of the anterior chamber

Fam Hx: family disorder, trauma, systemic illness

Ocular exam: slit lamp, determine the direction of displacement

Tx: Opthal will treat

Bilateral optic disc edema

Causes: intracranial mass, impediment of cerebrospinal flow, idiopathic intracranial HTN

Symptoms: HA,N,V, vision loss associated with postural changes, pulsatile tinnitis, horizontal diplopia

Signs: optic disc edema, both eyes

Papilledema

CN 6 palsy

-Atherosclerotic/thrombotic occlusion (artery supplying the optic disc)

-Hemodynamic compromise: severe hypotension/blood loss

Droopu eyelid (ptosis)

Diplopia: if ptosis doesnt cover eye

HA or periorbital pain

Eye is turned down and out

Def. in eye movement

Dilated pupil

Inn superior Obilque (tilts and depresses the eye)

S&S: vertical/oblique diplopia occurs

objects appear tilted

eye does not depress well when abducted

Innervates lateral rectus muscle

S&S: horizontal diplopia

HA or periorbital pain

Esotropia

Abduction deficit

Involuntary movement of the eye

Composed of mixture: slow and fast movements

Eye slowly drifts in one direction (slow phase)

Quickly returns to original position (fast phase)

Drift occurs at equal speed in all phases

Smooth back & forth motion

Wernicke encephalopathy(MOST COMMON)

Nonphysiologic: Cannot be sustained for more than 30 sec (physiologic/normal= <30sec)

Nystagmus

Eyes move in opposite direction of head turn

Associated with neurosyphilis

Pupil is small

Responds slowly or not at all

Accommodation & convergence is retained

No reaction to light

dilated pupil

Reacts poorly to light, better to accomodation

Usually unilateral

Most often seen in women

Associated with loss of DTR's

Viral etiology, inflammatory process

Confirming Dx: dilute solution of pilocarpine, adies will constrict, normal pupils won't

Injury to the sympathetic nerves of the face

Ptosis (ipsilateral)

Pupilary Miosis (constricted pupil)

Facial anhydrosis

Afferent Pupillary Defect (APD)

Nerve pathways dysfunction: failure to properly transmit messages

Light is shone in the abnormal eye, pupil of the affected eye paradoxically dilates