LASIK glossary of terms D-H

D

Decentration: A risk of LASIK surgery that is caused when the laser is not lined up with the center of the pupil, which can lead to glare, double vision, and halos.

Descemet's membrane: Portion of the cornea that is located between the endothelium and stroma.

Diopter: The refractive area in the eye that decides whether the eye is near or far sighted.

Dry eye: When the eye is unable to naturally produce the amount of tears needed to keep it properly lubricated. This the number one complaint of those who have had LASIK surgery.

E

Ectasia: The thinning of the cornea

Emmetropia: An eye that has perfect vision

Endothelium: the inner layer of cells in the cornea

Episclera: Portion of the sclera of the eye that connects it to the conjunctiva

Epithelial ingrowth: A risk factor of LASIK surgery where epithelial cells develop under the LASIK flap.

Epithelium: The outer layer of cells in the cornea

Excimer laser: Ultraviolet laser that is utilized in refractive surgery for the removal of tissue from the cornea.

F

Farsightedness: An eye problem, that is also called hyperopia, where objects that are close are harder to see then objects that are far away.

Femtosecond laser: Laser usually used in LASIK surgery in replacement of a microkeratome mechanical blade. The laser gives off a fast paced burst of energy to remove corneal tissue without damaging the area around it.

Fovea: Portion of the retina that allows acute vision

G

Ghosts: Risk factor of LASIK surgery where images are distorted

Glare: Risk factor of LASIK surgery that makes lights have luster around them.

Glaucoma: Eye condition that is caused when the fluids of the eye do not properly drain away, causing pressure to build inside the eye and damaging the optic nerve. This leads to loss of peripheral vision and can affect people of any age.

H

Haloes: Risk factor of LASIK surgery that causes rings to be seen around lights.

Haze: When the cornea is clouded, and it is like looking through a dense fog or smoke.

Higher-order aberration: Vision problems beside nearsightedness, farsightedness, and astigmatism that glasses or contact lenses cannot help and occur in about 15% of cases. They go by mathematical sounding experssions.

Hyperopia: What is referred to as farsightedness, when objects far away can be seen but close objects are blurry.