Laser-Assisted In Situ Keratomileusis (LASIK) is a surgical procedure that uses a laser to correct common vision problems by reshaping the cornea, the transparent front surface of the eye. This reshaping alters how light rays focus onto the retina, improving visual clarity for conditions like nearsightedness, farsightedness, and astigmatism. Custom LASIK represents an evolution of this established technique, moving from a standardized correction to a highly personalized treatment plan tailored to the unique characteristics of each eye. This approach accounts for subtle imperfections that affect visual performance.
The Core Difference: Wavefront Technology
The defining feature of Custom LASIK is the use of wavefront technology, a system designed to create a detailed map of the eye’s entire optical system. This specialized measurement involves directing a light ray into the eye, which reflects off the retina and passes into an aberrometer device. The device analyzes how the light wave has been distorted by the eye’s shape, providing a “fingerprint” of the eye’s refractive errors.
This detailed analysis captures basic refractive errors, known as lower-order aberrations (myopia, hyperopia, and astigmatism). The wavefront map also identifies higher-order aberrations, which are complex imperfections in the eye’s optics that conventional prescriptions do not measure. Examples include coma, trefoil, and spherical aberration, which affect visual quality. Wavefront mapping provides precision up to 25 times greater than standard measurements, measuring correction in increments of 0.01 diopters. This data forms the unique digital blueprint that guides the laser treatment.
The Custom LASIK Procedure Explained
The Custom LASIK procedure begins with the creation of a thin flap in the corneal tissue. This flap is typically created using a femtosecond laser, which uses rapid pulses of light to separate tissue layers with high precision. The surgeon gently folds this flap back to expose the corneal bed.
The wavefront data is electronically transferred to an excimer laser system. This laser is programmed to follow the custom blueprint, vaporizing microscopic amounts of tissue to sculpt the cornea’s surface. The laser system uses eye-tracking technology to remain aligned with the eye’s position, ensuring the corrections are applied exactly as planned. The excimer laser corrects both the lower-order errors and the higher-order aberrations identified by the wavefront analysis. After sculpting is complete, the corneal flap is carefully repositioned, where it naturally adheres without the need for stitches.
Who Needs Custom LASIK?
Custom LASIK is designed for patients who seek the highest possible quality of vision. While traditional LASIK corrects basic refractive errors, it can sometimes induce or fail to correct existing higher-order aberrations. These aberrations are often responsible for visual complaints, even in patients who achieve 20/20 vision after standard surgery.
Patients with significant pre-existing higher-order aberrations benefit most from the custom procedure. Correcting these imperfections translates into a reduction in visual side effects such as glare, halos around lights, and starbursts, especially during low-light conditions or night driving. Custom LASIK enhances contrast sensitivity, leading to sharper, clearer vision across various lighting environments.