What Happens at the LASIK Pre-Operative Exam?
- Auto Kerato-Refractometry: We use the top-rated device to measure your eyes refraction and corneal curvatures.
- Orbscan® IIz Cornea Topography and Pachymetry: A digital scan system is used to evaluate and map the front (anterior surface), back (posterior surface), and thickness of the cornea. This is extremely important information since the refractive surgery alters the original shape of the cornea.
- Zywave® II Wavefront Aberrometer: To better understand your particular vision and any impairment you may have, especially at night, the Zyoptix™ system maps thousands of data points, giving your doctor a fully detailed, three dimensional picture of your cornea’s shape and characteristics.
- Galilei™ Dual Scheimpflug Analyzer: Another device used to evaluate and map your cornea. This high precision optical system also determines the probability of Keratoconus, an eye disease that thins the cornea that may be occuring.
- Pupil Measurement: An infrared device is used to determine the maximum pupil size in complete darkness. Knowing the maximum pupil size is necessary in order to minimize night glare or halos after LASIK. The Technolas 217z allows us to adjust for the size of your pupils.
- Evaluate Visual Acuity: Your vision will be checked with and without your glasses and a dry refraction (before dilation) will be performed. Refraction is when we use lenses to find your best corrected vision. An accurate measurement of your visual acuity is the single most important factor before you have a permanent alteration in your visual system. If you are a contact lens wearer, we are especially concerned that your cornea is stable. This can be one of the most common causes of problems with refractive surgery. If you are a contact lens wearer, we will require you to discontinue their use up to 6 weeks prior to your evaluation, depending on the type you wear.
- External Ocular Evaluation: Using a slit-lamp binocular microscope, the anterior (front) segment of the eye is evaluated for eye disease involving the lids, conjunctiva (the lining of your lid and eye), tear film, cornea, ocular lens and iris.
- Intraocular Pressure: Eye pressure is measured via applanation tonometry, which is more accurate than the “puff” tonometry. Your eye pressure reading will be changed by refractive surgery; therefore, we believe that this pre-operative measurement is critical to your future eye health.
- Eye Dominance: This test will determine which of your eyes are dominant, similar to handedness. If you are over 40 years of age, you may want to consider under-correction of your non-dominant eye, referred to as monovision. This mild difference in your vision can leave you with a visual system that can still see near and mid ranges without reading glasses. We will discuss this with you at your initial examination.
- Wet Refraction: Using drops to dilate the eye, a cycloplegic (class of drugs used to artificially dilate the pupil) refraction is done to find out if there are any refractive changes after dilation. Your treatment may be modified to account for these changes, should they occur.
- Intraocular Evaluation: This is an evaluation of the posterior segment of the eye (vitreous and retina) via binocular indirect ophthalmoscope. We use this exam to rule out possible retinal diseases. In general, nearsighted people have more risk of some retinal problems. These are best treated prior to refractive surgery to reduce the risk of retinal detachment in the future. LASIK itself, as shown in numerous studies, does not increase the risk of retinal detachment.
When the evaluation is complete, your eyes will remain dilated for four to eight hours. Your near vision will be hindered and you will be light sensitive. This is why we ask you to bring a good pair of sunglasses. If you do not have a pair of sunglasses we will provide you with a pair of slip-ins.