Photorefractive Keratectomy (PRK) is a vision correction procedure that uses a laser to reshape the cornea, improving focus. Unlike LASIK, PRK requires the complete removal of the cornea’s outermost layer, the epithelium, before the laser treatment. This results in a more extensive healing process. Following your surgeon’s guidance on protective eyewear is essential, as it directly influences both comfort and the long-term clarity of your vision.
Understanding Post-PRK Light Sensitivity
The high reactivity to light, known as photophobia, stems from the mechanics of the PRK procedure. Removing the corneal epithelium, the eye’s natural protective barrier, leaves the underlying corneal tissue (the stroma) temporarily exposed. This exposure triggers an acute wound healing response involving inflammation and heightened sensitivity in the corneal nerve endings.
This irritation causes the intense discomfort and light sensitivity experienced during the first few days after surgery. Epithelial regeneration, which takes three to five days, requires a calm environment, as bright light can exacerbate the inflammatory response and increase pain.
Guidelines for Protective Eyewear
Wearing protective eyewear indoors and outdoors serves two distinct purposes: preventing long-term damage and ensuring short-term comfort. Outdoors, UV-protective sunglasses are mandatory 100% of the time, even on overcast days. Exposure to ultraviolet (UV) radiation is directly linked to the risk of developing corneal haze, a clouding of the cornea that can impair vision. For the first several months, sunglasses should offer 100% UV-A and UV-B protection, often specified as UV 400.
Indoors, the requirement shifts to immediate comfort. While UV light is less of a concern, the temporary hypersensitivity of the healing cornea makes many forms of artificial light painful. Fluorescent lights, computer screens, and bright lamps can cause significant glare and discomfort during the acute recovery phase. Wearing tinted or dark sunglasses indoors during the first one to two weeks is recommended to manage this temporary light hypersensitivity, allowing you to function with less strain and pain until the initial inflammation subsides.
The Timeline of Recovery and Protection
The need for protective eyewear relates directly to the phases of post-operative healing. The acute phase (the first three to seven days) is the period of highest sensitivity and discomfort, making glasses mandatory both indoors and outdoors. Minimizing light exposure supports the critical process of epithelial regrowth during this time.
In the intermediate phase, typically covering weeks two through four, light sensitivity decreases significantly. While outdoor UV protection remains required, the need for indoor eyewear generally becomes optional, based on comfort with screens and artificial lighting. The long-term phase extends for the first six to twelve months after the procedure. Even if sensitivity has resolved, wearing high-quality UV-blocking sunglasses outdoors is necessary to mitigate the risk of corneal haze development triggered by UV exposure.