Photorefractive Keratectomy (PRK) is a type of laser eye surgery that reshapes the cornea to correct refractive errors. Unlike LASIK, PRK does not involve creating a corneal flap; instead, the outermost layer of the cornea is removed before the laser treatment. This procedure causes light sensitivity, known medically as photophobia, which is a common side effect during the initial recovery period. This intense discomfort often leads patients to question the necessity of wearing sunglasses indoors. This article addresses the reasons for temporary light sensitivity and guides managing indoor light during healing.
The Cause of Post-PRK Light Sensitivity
The intense photophobia experienced immediately following PRK is a direct consequence of the surgical technique. During the procedure, the corneal epithelium, the thin, protective outer layer, is deliberately removed to allow the laser access to the underlying tissue for reshaping. This removal temporarily exposes the highly sensitive corneal nerves.
The cornea is densely innervated, and without its protective layer, light stimulation causes heightened discomfort and pain. A bandage contact lens is placed on the eye immediately after the procedure to serve as a temporary shield and promote healing. However, this lens does not fully alleviate the sensitivity until the epithelial cells have regenerated and covered the treated area.
The epithelial layer typically begins to regrow within the first few days. Until this surface heals, even normal indoor lighting can feel overwhelming, leading to symptoms like excessive tearing and a strong aversion to light.
Navigating Indoor Light During Recovery
The short-term answer to wearing sunglasses indoors after PRK is yes, driven by the need for comfort and pain management. During the initial recovery phase—typically the first four to seven days—darkened glasses significantly reduce painful light stimulation. At this stage, the practice mitigates photophobia caused by exposed corneal nerves, rather than providing UV protection.
Specific indoor light sources can be particularly aggravating. Bright overhead fixtures, especially high-output fluorescent or modern LED bulbs, often feel too intense for the recovering eye. Even indirect sunlight streaming through windows can cause discomfort, making protection advisable when resting inside a bright room.
Prolonged exposure to screens, such as monitors, phones, and televisions, should be limited during this initial period. If screen use is unavoidable, wearing sunglasses or using anti-glare glasses helps reduce strain and discomfort. Patients should prioritize comfort and adhere to their ophthalmologist’s post-operative instructions, which may include continuous use of dark glasses.
Knowing When to Stop Wearing Indoor Sunglasses
The need for indoor sunglasses is temporary and will decrease as the corneal epithelium heals. The transition away from indoor protection usually begins after the first few days, as the corneal surface regenerates. The bandage contact lens is typically removed by the surgeon around day five to seven, which often marks a point of significant reduction in acute pain and light sensitivity.
Objective signs of readiness to discontinue indoor use include reduced excessive tearing and a noticeable decrease in discomfort when exposed to ambient room light. Patients often report comfortably tolerating standard indoor lighting for short periods without needing sunglasses. The ability to view a screen without immediate, painful aversion is another good indicator of progress.
This phase requires a gradual approach, based entirely on patient comfort and the surgeon’s clearance. The transition should involve slowly reintroducing the eyes to normal indoor light levels, rather than abruptly stopping sunglass use. Although the eyes may still be sensitive for several weeks, the acute necessity for indoor sunglasses resolves within the first week following the procedure.
Long-Term Necessity of UV Protection
While the need for indoor sunglasses fades as the cornea heals, dedicated UV protection outdoors becomes a permanent habit following PRK. Laser reshaping of the cornea makes the eye more susceptible to complications from ultraviolet (UV) radiation exposure. UV light is a known risk factor for corneal haze, a clouding that can impact vision quality.
To minimize the risk of this long-term complication, 100% UV-blocking sunglasses are required for all outdoor exposure indefinitely, regardless of the weather. This protective measure is important during the first year after PRK, as the cornea continues its healing and remodeling process. Even on cloudy days, a significant amount of UV radiation can penetrate the atmosphere and reach the eye, necessitating consistent use.
The difference in protection is clear: short-term indoor use is for light comfort, while long-term outdoor use is for tissue protection from damaging radiation. Patients should wear high-quality sunglasses that filter both UVA and UVB rays whenever they are outside. This commitment to lifelong outdoor UV protection helps maintain the visual results achieved with PRK.