There are several basic refractive errors that caused by an imperfectly shaped eyeball, cornea or lens:

Myopia — nearsightedness; only nearby objects are clear.

Hyperopia — farsightedness; only objects far away are clear.

Astigmatism — images are blurred at a distance and near.

There's also presbyopia — "aging eye." The condition usually occurs between ages 40 and 50, and can be corrected with bifocals or reading glasses.

Who is a good candidate for LASIK?

It needs a baseline evaluation by an eye doctor to determine if you are a good candidate and taking measurements since LASIK is not for everyone.

LASIK is not recommended for patients with diabetes, cataracts, glaucoma, rheumatoid arthritis, herpes infections of the eye, or lupus. In one of these cases it should be discussed with the surgeon.

At least 18 years old (21 for some lasers), as vision of people younger than 18 usually continues to change.

Pregnancy or nursing is contraindication for LASIK, as these conditions might change the measured refraction of the eye.

The doctor should know about medication that is taken such as accutane or oral prednisone.

Patient with more than 8 dioptre myopia, more than 6 dioptre hypermetropia and more than 5 dioptre of astigmatism are not a good candidate for the procedure.

Adequate corneal thickness is necessary for this procedure and will be checked by the doctor.

Several weeks before the baseline evaluation contact lenses should be taken off, because they change the shape of the cornea, and switch to glasses. If it will not be long enough it might cause wrong consequences at the evaluation, and the result after surgery will be poor vision.

There might be a several measurements for determine how much corneal tissue to remove a week after the first evaluation to make sure that there is no change, especially if RGP or hard lenses were worn.

Time for stop wearing before the first evaluation:

Soft contact lenses- 2 weeks

Toric soft lenses or rigid gas permeable (RGP) lenses­ - At least 3 weeks

Hard lenses - At least 4 weeks

After an eye exam the doctor determine the eye health to know what kind of vision correction is needed, and how much laser ablation is required.

The doctor will use instruments such as: a slit lamp (to look into the back of the eye for retinal problems), a refractor (to determine your prescription), and a tonometer (to determine intraocular pressure — to avoid glaucoma).

Usually, the doctor uses also a corneal topographer. It photographs the eye and creates a kind of "map" of the cornea. The topographer shows the irregularities of the cornea, since no one has a perfectly rounded cornea. The photographer will show steepness or flatness that the surgeon must correct. There is a new "wavefront" devices that shows precise map of the aberrations by sending waves through the eye.

The doctor should perform and discuss if you are a good candidate and what are the risks and benefits of the surgery or advice for another treatment.
The doctor should inform what will happen during and after the surgery and the responsibilities as a patient before, during and after the surgery.

The doctor will answer for any questions during this discussion and would give informational literature provided. 

The day before surgery

Using perfumes, lotions, creams and makeup should be stopped. Using these products may increase the risk of infection during and after surgery.

Transportation must be arranged on the surgery day, as it is impossible to drive after the surgery.

During Surgery

The surgery takes less than 15 minutes. The patient lies back in a reclining chair in an exam room containing the laser system and then the doctor makes sure the eye is positioned directly under the laser (One eye is operated on at a time). The laser system includes a large machine with a microscope attached to it and a computer screen.

Before the start of surgery, the surgeon will program the computer based on the measurements that had taken at the baseline evaluation.

The eye numbs with eye drops, and a “lid speculum” holds the eyelids open. A ring places on the eye and very high pressures will be applied to create suction to the cornea. It might cause pressure and some discomfort during this part of the procedure. The patient will be asked to stare at a light of the laser that will be positioned over his eye. This laser is not used to remove tissue from the cornea, it helps to keep the eye fixed on one spot once the laser comes on, there are lasers that equipped with a special tracking device that follows your eye even if it moves. The surgeon will mark where the flap should be placed. Then the microkeratome blade or the laser (depending on the surgeon's preference) will cut a flap in the cornea. The patient is able to see, but will experience fluctuating degrees of blurred vision during the rest of the procedure.

When the eye is in the correct position, the surgeon will start the laser. The computer controls the amount of laser energy delivered to the eye. The pulse of the laser makes a ticking sound. At this time there might be a smell like mildly acrid odor. The surgeon has full control of the laser and can turn it off at any time. After the pulses of laser energy vaporize the corneal tissue, the flap is put back into position.

If the patient has both eyes done the same day, the surgeon will do the other eye after a short period of time

After Surgery

As a protection, a shield should be placed over the eye at the end of the procedure, since no stitches are used to hold the flap in place. This shield prevents from rubbing the eye and putting pressure on the eye while sleeping (rubbing the eye could dislodge the flap), and to protect the eye from accidentally being hit or poked until the flap has healed.

Immediately after the procedure, the eye may burn, itch, or feel like there is something in it, most people feel no more than mild discomfort, and the surgeon may suggest a mild pain reliever. Both eyes may tear or water. The whites of the eye may look red or bloodshot, it may experience sensitivity to light, and the vision will probably be hazy or blurry, glare, starbursts or haloes around lights. It should improve within the first few days after surgery.

Until symptoms subside it will be better to take a few days off from work.

Any experience of pain, or other symptoms get worse instead of better the doctor should be informed immediately.

At the first postoperative visit, 24 to 48 hours after the surgery, the doctor will remove the eye shield, test the vision, and examine the eye. The doctor may give prescription for one or more types of eye drops to take at home to help prevent infection and/or inflammation. The doctor may also advise to use artificial tears to help lubricate the eye.

Contact lens is not allowed to wear at the operated eye, even if the vision is blurry.

To help prevent infection, it may need to wait for up to two weeks after surgery before using lotions, creams, or make-up around the eye. The doctor may advise to continue scrubbing eyelashes for a period of time after surgery.

Many doctors advise few of days of rest. They also recommend no strenuous exercise for up to a week, since this can traumatize the eye and affect healing. It is important to protect the eyes from anything that might get in them and from being hit or bumped, therefore, contact sports such as football, karate, boxing, etc. should not be attempted for at least 1 month after surgery, swimming should be avoided for 1-2 months.

After LASIK

With LASIK surgery, most people's vision improves right away, but some find that their vision gradually improves even more over the next few days or even weeks.

Some people may still need glasses or contact lenses following laser vision correction, though their prescription level will be much lower than before. if you hit your 40s, you may still need reading glasses or bifocal contact lenses. This is because of a condition called presbyopia, which begins to develop in most people when they're between the ages of 38 and 42.

Postoperative complications can include infection or night glare (starbursts or halos that are most noticeable when you're viewing lights at night, such as while you're driving). Rarely, people will experience improvement, then notice a gradual worsening of vision (called "regression"). If this happens, discuss it with your surgeon to determine if more surgery (called an enhancement or "touch-up") will be necessary.

LASIK Medical Centers in Israel

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