Photorefractive Keratectomy (PRK) is a type of refractive laser surgery that corrects vision by reshaping the cornea. This procedure uses an excimer laser to precisely remove microscopic amounts of tissue, altering the curvature to correct errors like nearsightedness, farsightedness, and astigmatism. Individuals seek PRK for a long-term solution to reduce or eliminate their dependence on glasses or contact lenses. Understanding the durability of the results requires separating the permanent tissue change from the natural aging of the eye.
The Permanent Nature of PRK Reshaping
The core change performed by PRK—the reshaping of the corneal tissue—is permanent and irreversible. The excimer laser ablates microscopic layers of the corneal stroma, and this physical alteration to the eye’s structure remains for life. After the initial healing phase, which typically takes three to six months for vision to become fully stable, the corrected corneal shape is generally maintained.
Studies following PRK patients for a decade or more show a high degree of refractive stability. Many individuals maintain excellent vision without correction for 10 to 20 years and often longer. The long-term durability is an advantage of the procedure, as the cornea does not revert to its original shape. For most patients, the corrected distance vision stays sharp and consistent for decades.
A small percentage of patients may experience a slight return of their original refractive error, known as regression. This usually happens in the first year due to the eye’s natural healing response. The corneal surface epithelium, which is removed for the procedure, regrows, and in rare cases, this healing process can cause minor shifts in the curvature.
Age-Related Vision Changes PRK Cannot Prevent
While the PRK correction to the cornea is stable, the eye continues to age naturally, leading to vision changes unrelated to the surgery’s success. These changes are physiological and affect everyone, including those who have never had laser vision correction. The two main age-related issues that can affect vision after PRK are presbyopia and the development of cataracts.
Presbyopia is the gradual loss of the eye’s ability to focus on close objects, which typically becomes noticeable around age 40 to 45. PRK corrects a focusing error on the cornea, but it does not affect the crystalline lens located behind the iris. With age, this natural lens becomes less flexible and harder, losing its ability to change shape for near focus.
The need for reading glasses for close-up tasks is a sign of presbyopia, not a sign that the PRK procedure has failed or worn off. Later in life, usually after age 60, the natural lens may also become cloudy, a condition known as a cataract. Cataracts cause vision to become hazy or muted, and this process is completely independent of the previous PRK procedure on the cornea.
Options for Addressing Future Vision Decline
When vision changes occur later in life, various options exist to address new focusing needs related to aging. If a minor refractive error returns years after surgery, a secondary PRK procedure, often called an enhancement, can be performed to fine-tune the result. This is a possibility for patients whose vision has drifted slightly.
The most common age-related issue, presbyopia, can be managed with simple non-surgical methods. These include using over-the-counter reading glasses or specialized multifocal contact lenses. Some individuals also choose a monovision adjustment during their initial PRK, where one eye is corrected for distance and the other is corrected for near vision.
Cataract formation can be safely treated with modern cataract surgery, which involves removing the cloudy lens and replacing it with an artificial intraocular lens (IOL). Having had PRK does not complicate the surgery itself. However, it requires the surgeon to use specialized calculations and advanced diagnostic tools to accurately determine the correct IOL power. This extra step ensures a precise outcome, allowing patients to achieve excellent visual clarity.