Photorefractive Keratectomy (PRK) is a laser eye surgery that precisely reshapes the cornea to correct refractive errors like nearsightedness, farsightedness, and astigmatism. Unlike LASIK, PRK involves removing the outermost layer of corneal tissue (the epithelium) before the laser treatment, rather than creating a flap. This difference leads to a distinct healing process and raises questions about the subsequent use of contact lenses.
Immediate Post-Operative Contact Lens Use
Directly following PRK surgery, a specialized therapeutic or “bandage” contact lens is placed on the eye, but it is not for vision correction. Its purpose is to act as a protective layer. Since the removal of the corneal epithelium creates a superficial wound, the bandage lens shields the eye against the mechanical shearing that occurs when the eyelids blink.
This protective lens manages post-operative discomfort and reduces pain during the initial healing phase. It also promotes the regeneration of new epithelial cells by creating a stable, moist environment. Patients typically wear this lens for three to seven days. The surgeon will remove the bandage lens during a follow-up appointment, and patients must never attempt to remove or reinsert it themselves.
Timeline for Wearing Corrective Contact Lenses
While the primary goal of PRK is to eliminate the need for corrective lenses, some patients may eventually wish to resume wearing contacts. The eye must achieve complete stability and healing before any new corrective lens fitting can be considered. The cornea’s curvature changes significantly during the procedure and continues to remodel over several months.
New contact lenses cannot be successfully fitted until the corneal topography has stabilized, which typically takes between three to six months post-surgery. Wearing standard corrective lenses too soon can interfere with healing and potentially increase the risk of complications, such as infection. Because the cornea is permanently reshaped, previous contact lens prescriptions and measurements are no longer accurate. A new comprehensive eye examination and specialized fitting are necessary to ensure the lens rests appropriately on the newly flattened central cornea.
Specialized Contact Lens Options Post-PRK
If PRK leaves a residual refractive error or minor corneal irregularities, standard soft contact lenses may not provide optimal vision or a comfortable fit. The central flattening of the cornea, the desired surgical outcome, makes it difficult for standard soft lenses to center correctly. In these situations, specialized contact lens options are necessary to achieve the best visual acuity.
Rigid Gas Permeable (RGP) Lenses
One specialized option is the Rigid Gas Permeable (RGP) lens. Made of a durable material, RGP lenses do not conform to the corneal shape. The RGP lens creates a smooth, regular refracting surface over the eye, using the tear film trapped underneath to neutralize surface irregularities.
Scleral Lenses
Another highly effective choice is the scleral lens. This is a larger-diameter RGP lens that completely vaults over the cornea and rests on the less sensitive white part of the eye, known as the sclera. Scleral lenses are beneficial for post-PRK corneas with slight surface aberrations, as they provide a stable fit and a fluid-filled reservoir that keeps the ocular surface hydrated.
These specialized designs are required because the shape of the post-surgical cornea differs significantly from a normal eye, often necessitating a non-standard lens design to ensure proper alignment. Consulting a contact lens specialist experienced in fitting post-refractive surgery eyes is crucial for determining the most appropriate lens type.