Frequently Asked Questions

Does LASIK hurt?

Typically you experience little to no pain during the procedure as the eyes are completely anesthetized with numbing drops prior to treatment.

What does LASIK cost?

The cost of LASIK is determined by several variables, but two factors are generally recognized as the most important including 1) the technology utilized in treatment and 2) the training & experience of the surgeon. Discount laser centers typically utilize older or less advanced technology. At the Eye Institute, the price ranges from $1695/eye to $2595/eye depending on what is judged appropriate for you and your eyes. Excellent interest free financing plans are available.

How long is the recovery after LASIK?

Most people can return to normal functioning the next day after LASIK. Those who undergo PRK will typically return to normal functioning 3-7 days after treatment; however there is more variability with PRK than LASIK in healing time.

Will I need to have LASIK surgery done again?

Ten year data on LASIK and PRK indicates excellent vision stability over time. Those with stable vision prior to surgery are less likely to require additional surgery in the future. A small percentage of patients will require additional treatment.

What are the risks of LASIK?

Any surgical procedure will have risks. One reason for LASIK’s popularity is the low risk for complications such as loss of vision and the high probability of excellent vision. Our LASIK team will work to do an excellent job making sure you understand the potential risks, benefits and alternatives prior to surgery and that all of your questions are answered.

Why should I trust the Black Hills Regional Eye Institute?

The Eye Institute is the leading and most experienced provider of LASIK in the region. Dr. Khachikian is the region’s only fellowship trained refractive surgeon and Dr. Spencer has performed thousands of refractive procedures.

Can I see my local optometrist for any of my care?

We work with all eye care providers in the area and this often helps facilitate your care so you have less travel. We do ask you to come to our team of doctors for the surgery and the one-day follow up visit. All other appointments can typically be done with your local eye doctor.

How long does LASIK surgery take?

We ask you to plan on being at our clinic for 2 hours on the day of surgery. The surgery itself takes only 10-20 minutes and the laser time is typically between 15-60 seconds.

Will I need reading glasses after LASIK?

At a certain age (usually starting between age 40-50), if we correct both eyes for distance or far vision, than non-prescription reading glasses will be necessary for near vision. An alternative to this approach is monovision. Many of our patients desiring less dependence on reading glasses have success with monovision, which is a “blended” vision approach where one eye sees better for reading and one eye sees better for far vision. We have several methods of demonstrating this approach so you can “test drive” it prior to any surgery.

What does a LASIK exam cost?

The consultation to determine if you qualify for iLASIK is free!

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How long before surgery must I remove my contact lenses?

Daily soft lens wearers should leave out the lenses for seven days or longer before the pre-op exam and surgery. Extended wear (routinely sleep in lenses) or Toric lens wearers, should leave lenses out two weeks or longer before the pre-op exam and surgery. Hard or gas permeable lens wearers, should leave out lenses for four weeks or longer before the pre-op exam and surgery.

Do I absolutely have to be out of my contact lenses to determine if I'm a candidate for surgery?

If it is difficult for you to be out of your lenses, we can still complete your screening exam to determine if you are a candidate for surgery, however, you must remove the lenses prior to surgery as recommended.

Can I drive after my eyes are dilated during the pre-op exam?

If you do not think you would be comfortable driving after your eyes are dilated, you may want a driver. Most patients are comfortable driving as long as a pair of dark sunglasses are worn following the dilation.

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What should I plan for the day of my LASIK surgery?

You should plan for the following: 1) Have a driver. 2) Dress appropriately for 66-68 degrees in the Laser Surgery Suite. 3) Eat before you come to surgery. 4) DO NOT wear make-up, perfume, cologne, aftershave, or fragrant lotions. 5) Plan to be at our center for approximately 2 hours.

How long does the LASIK procedure take?

The procedure will take approximately 20-30 minutes. The actual laser time is 15-60 seconds. You will feel pressure, but typically not pain.

What happens before the surgery?

You will check-in for surgery about 1 hour before. At that time, we will review your post-op instructions, give you a valium for relaxation, and show you a video that explains each step. You will also be able to relax in our massage chair before your surgery.

When do I pay for my surgery?

Payment is expected the day of surgery. We accept cash, cashier’s check, Master Card, Visa, and Discover. Please visit the financing page to learn more about your options.

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What will my vision be like right after LASIK surgery?

Immediately after LASIK, you can expect foggy or "smoky" vision. You can also expect stinging, burning or foreign body sensation.

What should I do after my LASIK surgery?

It is best to go home and take a 2-3 hour nap. We also suggest you take extra strength Tylenol every 4-6 hours for discomfort.

What will be vision be like the night of my LASIK surgery?

Your vision will improve after you rest. You may use your eyes normally.

Can I rub my eyes after surgery?

You may use your eyes normally after surgery, but you should not rub your eyes for about one week after surgery.

What will my vision be like the day after LASIK surgery?

Your eyes may feel slightly sore and vision may still be slightly blurry.

Can I work the day after my surgery?

We suggest that you plan to take the day off after your surgery. Your vision may still be slightly blurry and fluctuate some. If you must work though, you can do so.

What can I expect in the days following my LASIK surgery?

Your vision may fluctuate. You may also experience some light sensitivity and may have dimming of vision in the evenings and some halos at night. iLASIK increases the chance for excellent vision and has quicker healing than older types of LASIK surgery.

Do I have to wear goggles after surgery?

You will wear clear goggles while you are sleeping for the first week after surgery.

How often will I see my doctor after surgery?

You will see our surgeon one day after surgery. Your post-op care is for a period of one year after surgery and you can see your Optometrist or an Eye Institute doctor for these appointments. These visits will take place approximately one week, one month, three months, six months and one year after surgery.

Are there certain restrictions after my LASIK surgery?

Restrictions for the first week after surgery include: 1) No swimming or hot tubs. 2) No rubbing of eyes. 3) Stay out of oceans, lakes or rivers.

Will I use eye drops after surgery?

You will use an antibiotic and steroid eye drop after surgery for approximately one week. Specific instructions will be given the day of your procedure. We also recommend Restasis and Optive for eye lubrication following surgery.

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What is retinal pigment epithelium?

This is the pigment cell layer just outside the retina that nourishes retinal visual cells. It is firmly attached to underlying choroids and overlying retinal visual cells.

What is preretinal membrane?

This is abnormal tissue lining the inner retinal surface, tending to wrinkle it. It may be thin and transparent, or thick, fibrous and opaque.

What is preretinal?

This refers to the area immediately in front of the retina and behind the posterior vitreous face.

What is the posterior chamber?

This it the space between the back of the iris and the front face of the vitreous; filled with aqueous fluid.

What is the vitreous?

This is a transparent, colorless gelatinous mass that fills the rear two-thirds of the eyeball between the lens and the retina.

What is a visual pathway?

This is the complete course of nerve fibers originating from the retinal visual cells as they travel to the occipital cortex in the brain.

What is the uvea?

This is pigmented vascular layers of the eye (iris, ciliary body, choroids) which contain most of the intraocular blood vessels.

What is trabecular meshwork?

This is a mesh-like structure inside the eye at the iris-scleral junction of the anterior chamber angle. It filters aqueous fluid and controls its flow into the canal of Schlemm, prior to its leaving the anterior chamber.

What is tear film?

Tear film is liquid that bathes the cornea and conjunctiva. There are three layers: outer oily layer secreted by the meibomian glands, middle aqueous layer secreted by the lacrimal glands, and inner mucin layer produced by the conjunctival goblet cells.

What is the tear duct?

This tear drainage channel extends from the lacrimal sac to an opening in the mucous membrane of the nose.

What is the tear drainage system?

These orbital structures are for tear production and drainage. Tears (produced in lacrimal gland above the eyeball) flow across the corneal surface, drain into the upper and lower puncta (openings at inner eyelid margins), through the upper and lower canaliculi to the common canaliculus, into the tear sac, then through the nasolacrimal duct into the nose.

What is the scotoma?

This is the non-seeing area within the visual field that may occur with damage to the visual pathways or retina.

What is sclera?

This is the opaque, fibrous, protective outer layer of the eye (white of the eye) that is directly continuous with the cornea in front and with the sheath covering the optic nerve behind.

What is the retina?

The retina is light sensitive nerve tissue in the eye that converts images from the eye’s optical system into electrical impulses that are sent along the optic nerve to the brain, to interpret as vision. It forms a thin membranous lining of the rear two-thirds of the globe and consists of layers that include rods and cones; bipolar, amacrine, ganglion, horizontal and Muller cells; and all interconnecting nerve fibers.

What is the pupil dilator?

This is a smooth iris muscle that contracts to enlarge the papillary opening. It extends like wheel spokes from the papillary margin to the iris periphery.

What is the pupil?

It is a variable-sized black circular opening in the center of the iris that regulates the amount of light that enters the eye.

What is the punctum?

This is a tiny skin opening of the lacrimal canaliculus of each upper and lower eyelid, near the nose. It is the entrance to the tear drainage system and each punctum is surrounded by a small papilla of skin.

What is a photoreceptor?

Also known as rods and cones, these retinal cells convert light into electrical impulses for transmission of messages to the brain.

What is the optic nerve?

This second cranial nerve is the largest sensory nerve of the eye and carries impulses for sight from the retina to the brain. It is composed of retinal nerve fibers that exit the eyeball through the optic disc, traverse the orbit, pass through the optic foramen into the cranial cavity, where they meet fibers from the other optic nerve at the optic chasm.

What is the nerve fiber layer?

This is the innermost retinal layer (closest to the vitreous). It contains axons from ganglion cells that follow a characteristic pattern toward the optic disc, where all fibers exit the eye as the optic nerve.

What is the meibomian gland?

This is an oil gland (one of a series) within eyelid tissue whose duct opens onto the eyelid margin just behind the gray line. Secretions supply the outer portion of the tear film, preventing rapid tear evaporation and tear overflow and providing tight eyelid closure.

What is the macula?

This is also known as “yellow spot”. It is a small central area of the retina surrounding the fovea and the area of acute central vision (used for reading and discriminating fine detail and color).

What is the lens capsule?

This elastic bag envelops the lens and helps control shape of lens for accommodation.

What is a crystalline lens?

This is the matural lens of the eye. It is a transparent, biconvex introcular tissue that helps bring rays of light to focus on the retina.

What is the lamella?

It is a layer of tissue; usually one of multiple similar layers, as in the corneal stroma.

What is the lacrimal sac?

This tear collecting structure is under the skin near the bridge of the nose. Tears enter from the common canaliculus and leave through the lacrimal duct in the nose.

What is a lacrimal gland?

This gland is an almond-shaped structure that produces tears. It is located at the upper outer region of the orbit, above the eyeball.

What is a lacrimal duct?

This is also known as the “tear duct”. It is a tear drainage channel that extends from the lacrimal sac to an opening in the mucous membrane of the nose.

What is the iris?

The iris is pigmented tissue lying behind the cornea that gives color to the eye and controls amount of light entering the eye by varying the size of the papillary opening. The iris is the most forward extension of the middle layer of the eye and it separates the anterior chamber from the posterior chamber.

What is the inferior rectus muscle?

This extraocular muscle is attached to the underside of the eyeball. It has three functions including depression (moves eye downward, especially when it is turned out); extorsion (rotates eye outward, especially on inward gaze), and adduction (inward eye movement).

What is the fovea?

This is the central pit in the macula that produces sharpest vision. It contains a high concentration of cones and no retinal blood vessels.

What is endothelium?

This is the single-cell layer of tissue lining the innermost surfaces of many organs, glands, and blood vessels. It also lines undersurface of the cornea, where it regulates corneal water content.

What is an eyelid?

This structure covers the front of the eye. Their function is to protect the eye, limit amount of light entering the pupil, and distribute tear film over the exposed corneal surface.

What is epithelium?

This is the membranous multicellular layer covering the internal and external surfaces of the body and its organs. In the eye, it covers the cornea, conjunctiva and eyelid.

What is the disc?

It is also know as “optic disc” or “optic nerve head” and is the ocular end of the optic nerve. The disc denotes the exit of retinal nerve fibers from the eye and entrance of blood vessels to the eye.

What is a dilated pupil?

This is an enlarged pupil, resulting from contraction of the dilator muscle or relaxation of the iris sphincter. It cccurs normally in dim illumination, or may be produced by certain drugs or result of blunt trauma.

What is the cornea?

The cornea is the transparent front part of the eye that covers the iris, pupil and anterior chamber and provides most of an eye’s optical power.

What is conjunctiva?

This is the transparent mucous membrane covering the outer surface of the eyeball (except the cornea) and inner surface of the eyelids, as one continuous membrane.

What is the choroid?

The choroid is the vascular (major blood vessel) layer of the eye lying between the retina and sclera. It provides nourishment to outer layers of the retina.

What is bowman’s membrane?

This is the corneal layer just under the epithelium and above the corneal stroma.

What is an A-scan test?

This is a type of ultrasound that uses very high frequency sound waves that are reflected by the ocular structures and converted into electrical impulses. An A-scan test is used for measuring the length of the eyeball prior to cataract surgery, to help determine the power of IOL to be implanted and also to help differentiate normal and abnormal eye tissue.

What is aqueous?

Aqueous is the clear, watery fluid that fills the space between the back surface of the cornea and the front surface of the vitreous, bathing the lens.

What is the anterior chamber?

This chamber is the fluid-filled space inside the eye between the iris and the innermost corneal surface.

What is the anterior capsule?

This is the front of the capsule enclosing the crystalline lens which lies in the posterior chamber just behind the iris.

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What is age-related macular degeneration (ARMD)?

ARMD is a condition that includes deterioration of the macula, resulting in a loss of sharp central vision. There are two types – dry and wet. This is the most common cause of decreased vision after age 50.

What is astigmatism?

This results in the inability of an eye to focus sharply (at an distance), usually resulting from a spoon-like (toric) shape of the normally spherical corneal surface. Instead of being uniformly refracted by all corneal meridians, light rays entering the eye are bent unequally, which prevents formation of a sharp focus on the retina. Slight uncorrected astigmatism may not cause symptoms, but a large amount may result in significant blurring.

What is a cataract?

A cataract causes opacity or cloudiness of the crystalline lens, which may prevent a clear image from forming on the retina. Surgical removal of the lens may be necessary if visual loss becomes significant, with lost optical power replaced by an intraocular lens.

What is farsightedness?

This is also known as “hyperopia”. It is a focusing defect created by an underpowered eye, one that has insufficient refractive power relative to its front-to-back length. Light rays from a distant object enter the eye and strike the retina before they are fully focused. Farsighted people can see clearly in the distance but only if they use more focusing effort than those who have normally powered eyes; close-up vision may be blurred because it requires even more focusing effort.

What is glaucoma?

Glaucoma is a group of diseases characterized by increased intraocular pressure resulting in damage to the optic nerve and retinal nerve fibers. It is characterized by typical visual field defects and increased size of optic cup. It is a common cause of preventable vision loss and may be treated by prescription drugs or surgery.

What is LASIK?

LASIK is the abbreviation for Laser in Situ Keratomileusis. It is a method of reshaping the cornea to change its optical power. After a flap of cornea is cut with an automated microkeratome and folded back, a computer-programmed excimer laser reshapes (sculpts) the exposed surface of corneal tissue, and the flap is replaced without suturing. LASIK corrects myopia, hyperopia, astigmatism.

What is nearsightedness?

This is also known as “myopia.” A focusing defect created by an overpowered eye, one that has too much optical power for its length. Light rays coming from a distant object are brought to a focus before reaching the retina. Nearsighted people see close-up objects clearly but distance vision is blurry.

What is an ophthalmologist?

This is a physician specializing in diagnosis and treatment of refractive, medical and surgical problems related to eye diseases and disorders.

What is presbyopia?

This is diminished power of accommodation arising from loss of elasticity of the crystalline lens and/or loss of ciliary muscle function, as occurs with aging. It usually becomes significant after age 45 and may also be caused by diseases such as hypothyroidism or glaucoma.

What is a retinal detachment?

This is a separation of the retina from the underlying pigment epithelium. It is almost always caused by a leaking retinal tear, which allows fluid to pass from the vitreous into the sub-retinal space. A detachment disrupts visual cell structure and thus markedly disturbs vision, often requiring immediate surgical repair.

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What is optic neuritis?

This is an Inflammation of the optic nerve and may accompany a demyelinating disease such as multiple sclerosis or infections from the meninges, orbital tissues, or paranasal sinuses. It is characterized by rapid onset of decreased vision and, usually, discomfort with eye movement and a central visual field defect.

What is optic neuropathy?

This is a non-inflammatory abnormality or degeneration of the optic nerve.

What is recurrent corneal erosion?

This is an episodic, periodic loss of the outer layer of the cornea (epithelium) due to its failure to adhere properly to Bowman’s membrane.

What is a retinal hole?

This is a tear through retinal tissue which usually is caused by a tug or traction by the vitreous which may leak, causing a retinal detachment. A retinal break may be created intentionally, as during retinal transposition surgery, and later closed.

What is a retinal ischemia?

It is an abnormal reduction of the retinal blood supply from varying degrees of blood vessel blockage. This may result in retinal edema, cotton-wool spots, microaneurysms, venous engorgement, and neovascularization.

What is retinitis?

This is an inflammation of the retina.

What is retinitis pigmentosa?

This is progressive retinal degeneration in both eyes. Night blindness, usually in childhood, is followed by loss of peripheral vision, progressing over many years to tunnel vision and finally blindness.

What is retinopathy?

This is any non-inflammatory degenerative disease of the retina.

What is retinopathy of prematurity (ROP)?

This is a series of destructive retinal changes that may develop after prolonged life-sustaining oxygen therapy is given to premature infants. In the active stage, findings include dilated, tortuous peripheral blood vessels, retinal hemorrhages, and abnormal newly formed blood vessels. ROP sometimes regresses and other times a peripheral fibrous scar forms that detaches the retina, resulting in vision loss or blindness.

What is a vitreous hemorrhage?

This is blood in the vitreous which may result from blunt eye trauma, blood leakage from neovascularization, vitreous detachment, or retinal tear.

What is neovascularization?

This is the formation of new abnormal blood vessels, usually in or under the retina or on the iris surface. It may develop in diabetic retinopathy, blockage of the central retinal vein, macular degeneration, sickle cell retinopathy, or retinopathy of prematurity.

What is nonproliferative retinopathy?

These are retinal changes associated with early diabetic retinopathy. Common retinal findings include microaneurysms, “dot and blot” hemorrhages, hard exudates, and dilation of retinal veins.

What is neuroretinopathy?

This is a non-inflammatory retinal abnormality occurring near the optic nerve.

What is neuroretinitis?

This is an inflammation of the retina near the optic nerve.

What is a macular pucker?

This is a retinal wrinkling in the macular area caused by contraction of the transparent membrane lying on the retinal surface.

What is macular edema?

This retinal swelling and cyst formation in the macular area usually results in temporary decrease in vision, though may be permanent. It frequently occurs to some extent after cataract surgery.

What is keratitis?

This is a corneal inflammation, characterized by loss of luster and transparency, and cellular infiltration.

What is an exudate?

This is a protein or fatty fluid that leaks from blood vessels into the surrounding tissue or spaces.

What is dry eye syndrome?

This corneal and conjunctival dryness is due to deficient tear production and can cause foreign body sensation, burning eyes, filamentary keratitis, and erosion of the conjunctival and corneal epithelium.

What is drusen?

These tiny, white hyaline deposits on Bruch’s membrane (of the retinal pigment epithelium) are common after age 60 and sometimes an early sign of macular degeneration.

What is a dislocated lens?

This is a partial or complete displacement of the crystalline lens from its normal position caused by broken or absent zonules.

What is diffuse lamellar deratitis (DLK)?

This is also known as “Sands of Sahara” and is a superficial clouding of the cornea under a corneal flap, with a granular-looking interface (between the surfaces), due to inflammation. It is a complication of LASIK that is usually reversible.

What is a cupped disc?

This abnormal enlargement of the optic cup (depression in center of optic disc) is most commonly due to prolonged increase in intraocular pressure.

What is a cotton-wool spot?

This “fluffy-looking” white deposit (resembles tufts of cotton) within the retinal nerve fiber layer represents small patches of retina that have lost their blood supply from vessel obstruction. It may be associated with hypertensive and diabetic retinopathies and certain collagen vascular diseases. These spots gradually disappear without treatment, leaving some functional loss.

What is a corneal ulcer?

This is an area of epithelial tissue loss from the corneal surface. It is associated with inflammatory cells in the cornea and anterior chamber.

What is conjunctivitis?

This is also known as “pink eye.” It is an inflammation of the conjunctiva and characterized by discharge, grittiness, redness and swelling.

What is a chalazion?

This is an inflammed lump in a meibomian gland (in the eyelid). Inflammation usually subsides, but may need surgical removal.

What is uveitis?

This is an Inflammation of any of the structures of the uvea: iris, ciliary body, or choroid.

What is proliferative diabetic retinopathy?

This is a retinal disease that includes abnormal growth of new blood vessels (neovascularization) and fibrous tissue. It usually develops because of insufficient oxygenation of retinal tissues in diabetes and leads to hemorrhage, retinal traction and detachment, and visual loss.

What is open-angle glaucoma?

This is the most common type of glaucoma. There is a gradual increase in resistance to normal outflow of aqueous from the eye despite an apparently open anterior chamber angle. If untreated, it results in gradual, painless, irreversible loss of vision.

What is fuchs’ dystrophy?

This is a progressive corneal disorder characterized by hyaline endothelial outgrowths on Descemet’s membrane, a cloudy waterlogged cornea, painful epithelial blisters, and reduced vision.

What is diabetic retinopathy?

This is a series of progressive retinal changes accompanying long-standing diabetes mellitus. Early stage is background retinopathy (non-proliferative) and may advance to proliferative retinopathy, which includes the growth of abnormal new blood vessels (neovascularization) and accompanying fibrous tissue.

What is choroidal neovascularization (CNV)?

CNV is the abnormal formation of new blood vessels in the choroids.

What is angle-closure glaucoma?

Angle-Closure Glaucoma is a rise in intraocular pressure, when aqueous fluid behind the iris cannot pass through the pupil and pushes the iris forward, preventing aqueous drainage through the angle. This occurs in patients who have anatomically narrow anterior chamber angles.

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What is a posterior capsulotomy?

This is an opening in the rear lens capsule when it has become opacified after previous cataract surgery. This is usually made with a YAG laser.

What is a corneal flap?

This is a thin layer of corneal tissue created by a microkeratome. It is part of a LASIK procedure.

What is a retrobulbar injection?

This is an injection (of a drug) behind the eyeball, into the center of the muscle cone. It is usually for anesthesia and akinesia (immobilization) of the eye.

What is retinotomy?

This is a retinal incision used for internal fluid drainage, relaxing scars, retinal translocation, or gaining access to subretinal membranes.

What is punctal occlusion?

This heat cautery or diathermy is applied to the lacrimal punctum in the eyelid to seal it. It can reduce tear drainage in patients who have insufficient tears or dry eyes.

What is photodynamic therapy (PDT)?

This is a two-step technique for treating neovascularization (abnormal blood vessels) associated with age-related macular degeneration (AMD). First, a dye that concentrates in neovascular blood vessels is injected into an arm vein. A few minutes later, those blood vessels are treated with a laser to close them off. Treatment often needs to be repeated.

What is an ablation?

This is a removal or destruction of tissue with x-ray radiation, light or laser energy.

What is a vitrectomy?

It is the removal of vitreous, blood, and/or membranes from the eye with a needle-like cutting device that has suction and fluid injection capabilities.

What is transpupillary thermotherapy (TTT)?

This is a technique of combining an injectible dye that concentrates in certain tissues followed by treatment with an infrared diode laser that heats the targeted tissue. It is used for treating small choroidal melanomas.

What is a trabeculotomy?

This is an incision into the trabeculum to increase aqueous drainage from an eye with glaucoma.

What is trabeculoplasty?

This is a application of a laser beam to selectively burn the trabecular meshwork area, to lower intraocular pressure. It is used for treating open-angle glaucoma.

What is a trabeculectomy?

This is a removal of part of the trabecular meshwork to increase outflow of aqueous from the eye; type of filtering procedure used in treatment of glaucoma.

What is selective laser trabeculoplasty (SLT)?

SLT makes small burns in the trabecular meshwork with a laser, to lower intraocular pressure. It is for treating open-angle and neovascular glaucoma.

What is a scleral buckle?

This technique is used in repairing a retinal detachment; material (usually silicone rubber) is sutured onto the sclera to indent (or buckle) it inward, applying localized pressure over the retina, to help seal a tear or reduce vitreous traction.

What is refractometry?

This objective testing is done to determine the combination of spheres and cylinders that will optically correct an eye without determining what prescription a patient will accept subjectively.

What is refractive surgery?

This is any surgical procedure to change the eye’s refractive error. It can reduce or eliminate the need for eyeglass or contact lens correction.

What is radial keratotomy (RK)?

This is a method of flattening the central cornea with 4-8 spoke-like (radial) incisions in the corneal periphery. It reduces the cornea’s optical power.

What is phototherapeutic keratectomy (PTK)?

PTK is a type of refractive surgery that uses an excimer laser to remove corneal tissue, to smooth an irregular surface, or remove corneal scars.

What is photorefractive keratectomy (PRK)?

PRK is a type of refractive surgery that uses a computer-controlled excimer laser to reshape the corneal curvature after the surface layer of the cornea is removed by gentle scraping. It corrects myopia and hyperopia.

What is phacoemulsification?

This is the use of ultrasonic vibration to break up a cataract into small fragments and emulsify (liquid) them, making them easier to suction out of the eye.

What is laser thermal keratoplasty (LTK)?

LTK is a method of reshaping the cornea to change its optical power. Heat is applied to the cornea with a laser to shrink the stroma, steepening the corneal curvature.

What is laser iridotomy?

This is the use of a laser light beam to burn a hole through the iris near its base. It is used for controlling eye pressure in angle-closure glaucoma.

What is keratotomy?

It is any incision into the cornea.

What is keratoplasty?

This is surgery on the cornea; usually refers to a corneal graft procedure (replacing scarred or diseased cornea with clear corneal tissue from a donor).

What is keratomileusis?

This refers to any lamellar refractive corneal surgical procedure that reshapes a portion of the corneal stroma to correct refractive errors. It is also a method of flattening the cornea to correct high myopia; a disc of cornea is shaved off, quickly frozen, lathe-ground to produce a more flattened optical lenticule, then returned to its original position; no longer used.

What is keratoconus?

This is a degenerative corneal disease affecting vision. It is characterized by generalized thinning and cone-shaped protrusion of the central cornea, usually in both eyes. This becomes apparent during 2nd decade of life, is hereditary, and can result in a corneal transplant.

What is Keratectomy?

This is the removal of corneal tissue.

What is an iridotomy?

A puncture-like opening made through the iris without removal of any iris tissue. It allows aqueous to drain freely from the posterior chamber to the anterior chamber.

What is an iridectomy?

It is a removal of a portion of iris tissue.

What is enucleation?

This is the removal of the eyeball, leaving eye muscles and remaining orbital contents intact.

What is an enhancement?

This is a surgical fine-tuning of an earlier procedure some time later, usually after some loss of refractive correction.

What is a corneal transplant?

A corneal transplant replaces scarred or diseased cornea with clear corneal tissue from a donor.

What is conductive keratoplasty (CK)?

Ck is a refractive surgery procedure that uses radiofrequency (RF) energy, instead of a laser, to reshape the cornea. CK modifies the curvature of the cornea, making it steeper and therefore improving vision. It is recommended for patients that are farsighted.

What is a clear lens extraction?

This is the removal of the eye’s clear natural lens to correct high myopia. In addition, an intraocular lens or a multifocal intraocular lens may be implanted to supplement the refractive correction.

What is astigmatic keratotomy (AK)?

AK surgery is a method of reshaping the cornea to correct astigmatism. Small incisions are placed in the cornea to flatten the corneal shape.

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What is a bifocal?

These type of eyeglasses incorporate two different powers in each lens, usually for near and distance corrections.

What is base curve?

This is the central curvature of the back surface of a contact lens (central posterior curve) or the posterior surface (when corrective cylinder is ground on the front surface) of a spectacle lens.

What is a prism lens?

This wedge-shaped, transparent medium bends light rays toward its base and does not focus.

What is a plus cylinder lens?

This lens has no optical power in one meridian (axis) and maximum plus-power in the perpendicular direction.

What is a plano lens?

This lens has no focusing power, neither plus or minus.

What is a multifocal lens?

This eyeglass lens incorporates more than one optical power to permit focusing at different distances.

What is an intraocular lens (IOL)?

This is a plastic lens that may be surgically implanted to replace the eye’s natural lens.

What is a bandage lens?

This soft contact lens has no refractive power and is used for protecting damaged or irregular corneal surfaces.

What is a trifocal?

This eyeglass lens incorporates three lenses of different powers. The main portion is usually focused for distance at about 20 feet, the center segment for about 2 feet, and the lower segment for near at about 14 inches.

What is a toric lens?

This lens has a cylindrical component and is used for correcting an astigmatic refractive error.

What is a soft contact lens?

This hydrophilic (water-absorbing) small plastic disc is used for correcting a refractive error or protecting a damaged corneal surface. It rests on the cornea; more comfortable than a hard contact lens.

What is a phakic intraocular lens?

This is a plastic lens that may be surgically implanted (placed either in front of or behind the iris) to work with the eye’s natural lens, to correct high refractive errors. Younger patients retain accommodative ability of their natural lens.

What is a hard contact lens?

This is a rigid plastic lens that floats on the corneal tear film.

What is a gas permeable lens?

This is a rigid plastic contact lens that allows oxygen and carbon dioxide penetration.

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What is an argon laser?

This laser is filled with argon gas and used for placing minute burns to destroy bits of iris, retina, abnormal blood vessels, tumors, etc.

What is a YAG laser?

This is a laser that produces a short pulsed, high energy light beam to cut, perforate, or fragment tissue. It sometimes is used following cataract surgery.

What is a femtosecond laser?

This laser can be used as a microkeratome, to make corneal flaps in refractive surgery.

What is an excimer laser?

This is a cold laser (filled with argon-fluoride gas) used in refractive surgery procedures such as PRK and LASIK to reshape the cornea. It is controlled by a computer and the laser emits a pulsating ultraviolet light that can ablate (vaporize) corneal tissue to a precise depth and area to produce a given optical correction, without heating it or surrounding tissues. This results in a smooth surface that heals rapidly with minimal scarring.

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What is pachymetry?

This is a test for measuring corneal thickness.

What is a prothesis?

This is a cosmetic “false eye” replacement for a removed (enucleated) eye. A plexiglas shell is painted to resemble a natural eye that fits into the conjunctival sac under the eyelids and over a buried implant.

What is a punctal plug?

This plastic material is inserted into the punctum to prevent normal tear drainage and to preserve tears for helping keep the cornea and conjunctiva moist.

What is vertex distance?

This is the distance from the front surface of an eye to the back surface of an eyeglass lens.

What is a keratometer?

This is used for measuring corneal curvature (K-readings) and for detecting and measuring corneal astigmatism.

What is a keratome?

This is any instrument used for cutting the cornea. The simplest type has a flat triangular blade.

What is a gonioscope?

This is a specialized contact lens used for examining anterior chamber angle structures.

What is a cycloplegic refraction?

This is an assessment of an eye’s refractive error after lens accommodation has been paralyzed with cycloplegic eyedrops (to eliminate variability in optical power caused by a contracting lens).

What is best-corrected visual acuity (BCVA)?

This is vision obtained with best possible lens correction.

What is acuity measurement?

This is a measurement of an eye’s ability to distinguish object details and shape. It is assessed by the smallest identifiable object that can be seen at a specified distance.

What is wavefront analysis?

This is for photorefractive surgery and evaluates image-forming rays of light coming from an eye so as to direct a computer-controlled laser to reshape the corneal surface for an accurate optical correction.

What is visual acuity?

This is an assessment of the eye’s ability to distinguish object details and shape, using the smallest identifiable object that can be seen at a specified distance (usually 20 feet or 16 inches).

What is uncorrected visual acuity (UCVA)?

This is vision obtained without using an optical aid.

What is an ultrasound?

This evaluates transmission of high frequency sound waves into the eye, which are reflected by the ocular tissues and displayed on a screen so that internal structures can be visualized. It permits intraocular distance measurements and aids in diagnosis of eye and orbital problems.

What is a tonopen?

This is the trade name of compact electronic tonometer that provides a digital reading of intraocular pressure

What is tonometry?

This is a measurement of intraocular pressure in millimeters of mercury.

What is a tonometer?

This is a device that measures intraocular pressure.

What is tonography?

This determines how fast intraocular pressure is reduced by pressure on the eye and is based on how easily fluid can be forced out of the eye by pressing on the cornea with a fixed weight.

What is tear breakup time?

This is a test for tear function. When the time interval between a blink and the development of a dry spot in the pre-corneal tear film is less than 10 seconds, it is abnormal. A spot is visible after fluorescein staining, especially with the cobalt blue beam on the slit lamp.

What is a speculum?

This is used for holding the eyelids apart, to give better access to the eyeball during a surgical procedure.

What is the snellen chart?

This chart is used for assessing visual acuity. It contains rows of letters, numbers, or symbols in standardized graded sizes, with a designated distance at which each row should be legible to a normal eye. It is usually tested at 20 feet.

What is a slit lamp?

This table-top microscope is used for examining the eye and allows cornea, lens and otherwise clear fluids and membranes to be see in layer-by-layer detail. This lamp has a low magnifying power with a light source that projects a rectangular beam that can be changed in size and focus. It is one of the most important ophthalmic instruments.

What is a schirmer test?

This test is for measuring tear production. Filter paper strips are placed in lower fornix. If topical anesthetic is used, the test measures basic secretion of the accessory glands; if not tearing comes from lacrimal glands (reflex tearing).

What is retinoscopy?

This is a test that measures an eye’s refractive error by using a retinoscope.

What is a retinoscope?

This hand-held device is for measuring an eye’s refractive error with no response required from the patient. Light is projected into the eye, and the movements of the light reflection from the eye are neutralized (eliminated) with lenses.

What is a pupillometer?

A pupillometer is used for measuring the distance from the center of the pupil to the center of the bridge of the nose for fitting spectacles.

What is a phoropter?

This is a refraction device that incorporates a series of spherical and cylindrical lenses, with prisms, occluders and pinholes. It is used to determine an eye’s optical correction.

What is a pachymeter?

This instrument is used for measuring corneal thickness or anterior chamber depth, using the optical principle of split images.

What is ophthalmoscopy?

This is the use of an ophthalmoscope to examine the internal structures of the eye, especially the fundus (rear surface of the eye).

What is an ophthalmoscope?

This illuminated instrument is used for visualizing the interior of the eye. A direct ophthalmoscope provides a magnified (15x) upright view with a small field of view and consists of a bright light source and incorporated focusing lenses. An indirect ophthalmoscope creates an inverted, magnified (3x) image of the fundus projected in front of the eye, with a wide field of view and consists of a bright light source and a hand-held high-plus lens.

What is a manifest refraction?

This presentation of a series of test lenses in graded powers is done to determine which corrective lenses provide the sharpest, clearest vision.

What is a microkeratome?

This cutting device is designed somewhat like a carpenter’s plane and used for dissecting (shaving) a precise thickness of tissue from the corneal surface.

What is a low-vision aid?

It is a high-powered plus lens and telescope with high magnification to help patients who have poor vision.

What is a lid speculum?

This is used for holding the eyelids open and apart for examination or surgery.

What is a lensometer?

This instrument is used for determining the refractive power of an eyeglass or contact lens.

What is a K-reading?

K-reading is a corneal curvature measurement obtained with a keratometer. Unequal measurements indicate astigmatism.

What is keratometry?

Keratometry obtains corneal curvature measurements with a keratometer. Unequal meridional powers indicate astigmatism.

What is a jones test?

This test is done to evaluate tear drainage system function. It also measures the time for fluorescein dye to appear inside the nose after being dropped onto the cornea.

What is hand movement?

This is the patient’s ability to see movement of a waving hand at a specified distance, usually 1 ft. or less and is used when vision loss is too profound for counting fingers.

What is gonioscopy?

This is an examination of the anterior chamber angle structures through a specialized contact lens, with a slit lamp or hand-held microscope.

What is a fundus camera?

This camera is used for taking pictures of the retina and inner lining of the eye, particularly the posterior pole.

What is fundoscopy?

This is a fundus examination with an ophthalmoscope.

What is fluorescein