|This image shows cells being rapidly released through a
chemical reaction caused by the cold excimer laser used
for Lasik. Although not burned, the reaction can cause the
unpleasant smell of burning flesh.
conventional or wavefront custom Lasik, Bladeless Lasik, PRK, LASEK, Epi-Lasik,
laser eye surgery, patients often exclaim, "I can see!",
shortly followed by, "What was that smell?" The process of laser
eye surgery can cause the disconcerting smell of burning flesh.
The excimer laser is a "cold" laser and does not remove tissue with
heat. The concentrated light frequency disrupts the molecular bonds
that hold together the corneal cells. Without these bonds the cells escape in the form of a mushroom
cloud that looks similar to an atomic bomb.
As these cells rapidly move away from the cornea they strike
each other causing a minor heat buildup from friction. That buildup
can raise the temperature of the cornea to about 110°F (43°C), or
around 11°F (6°C) above normal body temperature and very close to
the water temperature of a nice warm hot tub. A second-degree burn
threshold is skin temperature raised to 175°F (79°C). A third-degree
burn threshold is skin temperature raised to 200°F (93°C).
Chemical Reaction, Not Heat
The smell, which is remarkably like the smell of burning flesh,
is from the chemical reaction of the laser on the cornea, not from
heat. Some surgeons use a special vacuum device surrounding the eye
that removes these cells throughout the procedure so the source
of the unpleasant smell is removed. Even if it is only a chemical
reaction via laser and not heat, nobody wants to experience what
smells like their eye burning.
Looking For Best Lasik Surgeon?
If you are ready to choose a doctor to be evaluated for conventional
or custom wavefront Lasik, Bladeless Lasik, PRK, or any refractive surgery procedure, we recommend you consider a doctor who has been evaluated and certified by the USAEyes nonprofit organization.
Locate a USAEyes Evaluated & Certified Lasik Doctor.
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