What Are the Tests in a LASIK Eye Exam?

A LASIK eye exam will help determine if you're an ideal candidate for laser eye surgery. Woodhams Eye Clinic uses the most advanced diagnostic eye equipment to ensure that your procedure has the best possible outcome.

Refractive Error Diagnosis

First, the surgeons must determine what the level of your refractive error is — how much to reshape the cornea, which is essentially the same as determining what lenses to give you if you were getting a prescription for contacts or glasses. But while many optometrists would need to ask "Now which is better, one or two?" about a hundred times and use that to plan your treatment, the doctors at Woodhams will perform several additional tests to determine your candidacy for vision correction.

Woodhams Eye Clinic has a more sophisticated method: the EPIC-5100 Vision Diagnostic System. This technology can measure nearsightedness, farsightedness, and astigmatism as precisely as 1/8 of a diopter. All you have to do is look into the machine. While they often still fine tune patients' refractive error using the traditional method, the EPIC measurement provides a good starting point and minimizes the time required for your exam.

Wavefront (CustomVue)

In order to provide Wavefront-customized LASIK, first your eye must be thoroughly mapped. This is where the CustomVue system comes into the diagnostic process. It does more than simply measure the overall shape of your eye to determine what strength of correction is required; it measures the shape of the individual bumps and divots on the surface of your eye. These irregularities, known as higher order aberrations, cause a reduction in visual clarity without altering your refractive prescription. Regular LASIK, without Wavefront customization, has been shown to increase higher order aberrations. The Wavefront portion of the LASIK eye exam, like the EPIC refractive diagnosis, involves simply looking straight ahead while the computer records detailed images of your eye.

Optical Quality Analysis System (OQAS)

The Wavefront system maps your higher order aberrations; the OQAS measures their effects on your visual clarity. A patient can have no refractive error — be 20/20 — yet experience visual errors like halos and starbursts in low light or blurry segments of his visual field from early-stage cataracts. The OQAS measures the extent to which these aberrations affect your vision and is a particularly useful tool to measure your progress after surgery.

Optical Coherence Tomography (OCT)

The OCT section of your exam, like the other parts, involves looking straight ahead and is over in the time needed to take a simple photograph. In that split second, the OCT measures the surface of the back of your eye. The results of the OCT help the surgeon to predict if complications during LASIK are likely and also to diagnose diseases including glaucoma, macular edema, and diabetic retinopathy.

We also perform the standard tests for refracting and eye pressure and glare testing for patients over 50. The entire process of a LASIK eye exam, as thorough as it is, uses extremely advanced technology and is completely painless. A LASIK exam is a very thorough look at all aspects of your vision and ca take up to 2 hours or more, including your conversation with the doctor about your options.

For questions or comments, contact Woodhams Eye Clinic.