by Gary Allen & Dona Do

1) Retina

2) Cones & Rods

3) Fovea Centralis

4) Macular Plaque

5) Optic Nerve

What is it? Who gets it? Why would you

want it? What are the risks? What are the

benefits? How expensive is

it?

Refractive surgery is the correcting of a refractive error by changing the shape of the cornea with surgery.

Objects at distance are blurry & difficult to see.

Objects at proximity more clearly defined.

Corrected by Convex lenses as shown on diagram C & D

Difficulty seeing clearly at close distances

Objects at a distance more easily discernable.

Corrected by Convex lenses as shown on diagram A & B

Irregular curvature of the eye (shaped more like football than basketball)

Light in different planes focuses at different points

Flattening the cornea decreases myopia Increasing the steepness of the cornea

decreases Hyperopia Making the cornea more spherical

decreases Astigmatism All of these are correctable to some greater

or lesser degree through refractive surgeries

There are three types of surgery available utilizing Laser, Incision procedures or intraocular implants

Laser: Incision LASIK RK & AK PRK Intraocular LTK IOL

A flap is cut in the anterior cornea A laser is applied to the stroma underneath The flap is then replaced Pro- can treat large refractive errors shorter

healing time than PRK Local anesthetic (out patient procedure) Con-cost price ranges from $2,500-$1,000

Central Epithelium is Removed Laser is applied to bowman’s membrane Local anesthetic used 30 seconds of laser exposure Pro- can treat large refractive errors Con- greater laser exposure longer healing

time than LASIK.

Less common procedure LTK treats mild far-sightedness and also

provides a means of treating presbyopia (age-induced farsightedness)

Uses heat to steepen cornea Pro- lower incidence of complications for

LTK than with LASIK, with less than 1% adverse events

Con- only used to treat mild presbyopia

RK= Radial keratotomy for myopia AK= Astigmatic keratotomy for astigmatism Incisions in cornea heal causing reshaping

of eye Pro-can be done in poorer countries Con- higher risk of complications, less

effective, obsolete

Phakic Intraocular lenses Implanted into eye without removing the

natural lens Refractive lens-ectomy Natural lens is removed from eye and

replaced with intraocular lens PRO- for high myopia and cataracts Con- cost upwards of $1500 per eye.

1) Must have had no vision changes for at least two years

2) No underlying corneal

abnormalities3) No use of

contact lenses prior to surgery

Some anti-inflammatory medications are required

Possibility of infection based on procedure

Sunglasses outside are recommended for the first two weeks

Eye rubbing can cause damage

Some problems with glare can be noticed

Vision can be improved to 20/20 or greater but there is no guarantee of perfect vision.

Over time the corneal shape can gradually change requiring the need of glasses for reading this usually happens to candidates over 40-50 years of age.

What is it?

Who gets it? Why would you want

it?

What are the risks?

What are the benefits?

How expensive is it?

The evolution in correction of vision

Any one who fits criteria & wants better vision

Very small 0.1-0.9% have some form of complications

Benefits include improved vision to greater or lesser degree.

Prices Range $1000-$2500 per eye