Before undergoing a LASIK surgery, there is a complete set of tests that are performed by the eye specialist on the patient. These tests are done to examine the eye health and vision of the patient and ensure that he is a suitable candidate to undergo LASIK eye surgery. The tests include an examination of the corneal composition, shape and thickness, the optics of eyes, tear production, intraocular pressure, pupil size, lubrication of the eyes and refraction. All these factors are considered for determining if a patient is suitable for undergoing LASIK. While the tests are performed by the eye specialist, he uses eye drops to dilate the patient’s eye, which allows him to examine the eyes more carefully. The eye drops cause a blurry vision for 4-6 hours. For the LASIK exam, it is suggested to not wear their contact lenses in the weeks before the tests to ensure that the eye specialist gets correct examination results before performing LASIK. Corneal Composition, Shape and Thickness A corneal examination is performed as a pre-operative LASIK eye exam to accurately measure the patient’s prevailing eye conditions. The cornea is your eye’s clear, protective outermost layer, which is a dome-shaped surface covering the front of the eye. The eye specialist will examine the outside and inside surfaces of the cornea. A device, known as a corneal topographer, is used to measure the curvature of the eye and create a map of the eye before the LASIK. This helps the eye specialist to determine specifications for the surgery. He will examine the overall thickness of corneal walls to determine corneal strength before LASIK and will also look for diseases or abnormalities of the cornea. A thin cornea can cause problems and thus make a patient non-eligible for LASIK. Here the doctor recommends other methods of vision correction for such patients. They are- Intraocular Pressure Another eye test is the examination of intraocular pressure to rule out any chances of glaucoma in the eyes of the patient. Glaucoma is a condition caused by increased pressure in the eyes that can possibly damage the optic nerve and vision. Glaucoma usually occurs when the fluid in the eyes cannot drain well, thus putting pressure on the optic nerve as a result. Hence, eye specialists will examine the patient for glaucoma before undergoing LASIK. Eye Lubrication Eye specialists test for the quality and quantity of tears to see if the patient will be at an increased risk of dryness in the eyes after LASIK. As a pre-operative LASIK test, the doctor examines tear production in the eyes. Tear production is essential for the cornea as they keep the eyes lubricated, prevent infection and help in healing wounds. Measurement of Pupil Measuring the pupil size is a crucial pre-operative LASIK test done by doctors. Certain patients with larger pupils can sometimes be at a risk for possible side effects such as glare or halos after the LASIK surgery. Refraction As a pre-operative LASIK test, the doctor examines the short-sight, long-sight and astigmatism. This test will accurately measure the prescription of the spectacles of the patient. In order to be eligible for LASIK eye surgery, the candidate must have a refractive error that has been stable for more than a year. ------CHANGE TO ATLEAST 6 MONTHS The doctor will examine the spectacles prescriptions and confirm this multiple times during the tests and the whole LASIK treatment. Discussion of Medical History and Lifestyle This step is not a test but a conversation between the doctor and the patient where the patient must inform his doctor of any pre-existing medical conditions that may be a possible threat to his vision after LASIK surgery. The doctor also discusses lifestyle changes and habits of the patient and gets to know his medical history, ongoing medication and prescriptions. All this helps the doctor in determining any risks that the patient may face after the LASIK surgery. These eye tests need to be passed by the candidate successfully in order to be eligible to undergo the LASIK eye surgery.