The document discusses refractive surgery procedures for correcting vision, including LASIK, PRK, and lens implants. It describes how each procedure works to reshape the cornea and lens to reduce nearsightedness, farsightedness, and astigmatism. The risks are generally low but include infection, glare, and gradual refractive change over decades. The benefits are improved vision, though not necessarily perfect vision. Costs typically range from $1000 to $2500 per eye.

1. by
Gary Allen & Dona Do

4. 1) Retina
2) Cones & Rods
3) Fovea Centralis
4) Macular Plaque
5) Optic Nerve

7.  What is it?
 Who gets it?
 Why would you want
it?
 What are the risks?
 What are the
benefits?
 How expensive is it?

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

10.  Objects at distance are
blurry & difficult to see.
 Objects at proximity
more clearly defined.
 Corrected by Convex
lenses as shown on
diagram C & D

11.  Difficulty seeing clearly
at close distances
 Objects at a distance
more easily
discernable.
 Corrected by Convex
lenses as shown on
diagram A & B

12.  Irregular curvature of the eye (shaped more
like football than basketball)
 Light in different planes focuses at different
points

13.  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

14.  There are three types of surgery available
utilizing Laser, Incision procedures or intraocular
implants
 Laser: Incision
LASIK RK & AK
PRK Intraocular
LTK IOL

16.  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

17.  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.

18.  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

20.  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

21.  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.

23. 1) Must have had no
vision changes for
at least two years
2) No underlying
corneal abnormalities
3) No use of contact
lenses prior to surgery

24.  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.

25.  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