Real-Life Communication
You are an ophthalmologist at a laser surgery eye center. A patient,
Violet, has been wearing contact lenses for years and is interested in possibly
getting laser surgery on her eyes. Like many, she is nervous about the procedure.
You examine Violet and determine that she is a suitable candidate
for laser surgery. Next you talk to her, explain the procedure, and try to
help her decide whether or not she wants to proceed.
Read the description
of laser surgery below. Then answer Violet's questions at the end.
Laser
surgery treats vision problems such as near-sightedness, far-sightedness and
astigmatism. It uses a computer-controlled excimer laser, a form of ultraviolet
laser that generates almost no heat.
Prior to surgery the patient
is given special eye drops that numb the eye. During the surgery a device
called a speculum holds the eyelid open.
The beam of cool laser light
is used to carefully reshape a thin layer of the cornea. The laser is very
precise -- it has up to .25 microns of accuracy. By comparison, a human hair
is about 50 microns thick. The removal of corneal tissue with laser pulses
flattens the curvature of the cornea and improves the eye's ability to focus.
Because these pulses "dissolve" the molecular bonds of the corneal
tissue without generating any heat, nearby tissues are not damaged. The structural
integrity of the cornea is also protected.
Laser surgery patients
who wear contact lenses are asked to not wear them for several days prior
to the surgery. Following the procedure, you will be asked to keep your eyes
closed for several hours and to use eye drops. There is typically a follow-up
appointment the day after the surgery, and several more after that. These
allow the doctor to check how well your eyes are healing.
Since 1988,
more than four million excimer procedures have been performed worldwide.
(Excerpted
from Dr. Stuart Landay's website with permission)
These
are the questions that Violet asks you:
- Can laser surgery correct my astigmatism?
- How does the computer reshape the eye?
- When I think of lasers, I think of heat. Is the laser hot?