In surgery, to remove
Removal of tissue with the excimer laser
Area of tissue that is removed during laser surgery
Clearness or sharpness of vision
A defect of vision in which the image of an object is distorted, usually due to a football-shaped curvature of the cornea.
Automated Lamellar Keratoplasty (ALK)
A refractive surgery procedure for patients with high nearsightedness where a “pancake” of corneal tissue is removed with a microkeratome.
The transparent circular part of the front of the eyeball. It refracts the light entering the eye to focus it onto the retina.
A computer-generated map of the surface curvature of the cornea.
A diseased or scarred cornea is replaced with a healthy cornea.
Tthe measurement of refractive error; a negative diopter signifies an eye with myopia (nearsightedness), a positive diopter signifies an eye with hyperopia (farsightedness)
Layer of cells on the inside surface of the cornea
Outermost layer of cells of the cornea and the eye’s first defense against infection
Complication of refractive surgery in which scatter from bright light decreases vision
Complication of refractive surgery in which patient sees rings around lights due to optical imperfections in or in front of the eye
A Latin term meaning “in place” or not removed
The colored part of the eye; suspended behind the cornea and immediately in front of the lens
Surgical removal of corneal tissue
Surgical incision of the cornea
Inflammation of the cornea
Prefix indicating relationship to the cornea
Rare, inherited disorder characterized by an irregular corneal surface (cone-shaped) resulting in blurred and distorted images
Surgical reshaping of the cornea
Replacement of the cornea
Laser Correction of Nearsightedness
Vision is corrected or improved with an excimer laser, which uses a very thin beam of light of high energy to sculpt small amounts of tissue from the corneal surface, also called photorefractive keratectomy (PRK) or LASIK.
LASIK refers to Laser In Situ Keratomileusis. After a “pancake” of corneal tissue is prepared and folded back, the excimer laser is used to sculpt a small amount of corneal tissue to correct nearsightedness.
Part of the eye that changes shape, allowing the eye to focus at different distances
Instrument a surgeon uses to create the corneal flap in the uppermost layer of the cornea during the LASIK procedure
Purposeful adjustment of dominant eye for distance vision and the other for near vision
Surgeon’s adjustment to the laser’s computer calculation to further refine results
Complication of refractive surgery where the desired amount of correction exceeds attempted results
Phototherapeutic Keratectomy (PTK)
An excimer laser treatment for patients with diseases of the cornea, corneal dysfunction, abnormalities, or scarring.
Photorefractive Keratectomy (PRK)
Another term for laser correction of nearsightedness.
Procedure involving the removal of the surface layer of the cornea (epithelium) by gentle scraping and use of a computer controlled excimer laser to reshape the stroma
Age related inability to focus on near objects due to reduced elasticity of the lens; usually begins to surface between ages 40-45
Hole in the center of the iris that changes size in response to changes in lighting
Radial and Astigmatic Keratectomy (RK and AK)
Radial incisions on the surface of the cornea correct nearsightedness; arcuate incisions are used to correct astigmatism.
The change in the direction of light rays when they pass from one transparent medium to another of a different density. Errors in refraction occur when light rays do not come to a focus on the retina due to curvature of the cornea or lens, causing nearsightedness, farsightedness, or astigmatism.
Hyperopia, myopia and astigmatism
Layer of fine sensory tissue that lines the inside wall of the eye; captures images, much like film in a camera, and transforms images into electrical signals and sends to brain
A secondary refractive procedure performed after the initial one in an attempt to achieve better visual acuity
Tough, white, outer layer (coat) of the eyeball that , along with the cornea, protects the eyeball
The middle, thickest layer of tissue in the cornea
Complication of refractive surgery where the desired amount of correction is not fully achieved
Clearness of vision; ability to distinguish details and shapes