LASIK and High-Altitude Mountaineering: What the Evidence Shows

High-altitude environments place unique physiological stress on the human body, including the eyes. Hypobaric hypoxia, increased ultraviolet (UV) exposure, cold, wind, and extreme dryness can all affect visual function. As a result, climbers and outdoor athletes often ask whether undergoing LASIK is safe for high-altitude mountaineering.

A persistent myth suggests that LASIK patients may lose vision or go blind at altitude. Current scientific evidence does not support this claim.

Does LASIK Increase the Risk of Vision Loss at High Altitude?

No. There are zero documented cases of permanent vision loss caused by high altitude in patients who have undergone LASIK.

Multiple studies and case reports evaluating climbers, pilots, and high-altitude travelers demonstrate that LASIK-treated eyes remain structurally stable and functionally safe in hypoxic environments.

Key Findings from the Literature

• Studies evaluating climbers with LASIK-treated eyes have shown no permanent changes in visual acuity or ocular health with ascent.

• In a study of 12 mountaineers with prior LASIK, no visual changes were detected across varying altitudes, despite known environmental stressors such as dryness and cold.

• Case reports of climbers ascending Mount Everest describe stable or perfect vision at extreme altitude. A small number of climbers reported mild visual blurring, which resolved completely with descent.

• When visual changes occur, they are temporary and reversible, most commonly described as a mild myopic shift.

When Can Visual Changes Occur?

Rare cases of transient visual changes have been reported only in the early postoperative period, typically within 8–14 weeks after LASIK. These changes appear to correlate with:

• Extreme altitude exposure

• Prolonged hypoxia

• Reduced peripheral oxygen saturation

Importantly, all reported visual changes resolved after descent, with no long-term consequences. For this reason, patients are generally advised to allow adequate healing time before undertaking high-altitude expeditions.

LASIK vs. Older Refractive Procedures

LASIK demonstrates significantly greater refractive stability at altitude compared to older procedures such as radial keratotomy (RK). RK is known to cause unpredictable refractive shifts in hypoxic conditions, whereas LASIK maintains corneal integrity and optical stability.

Professional Guidelines

The Wilderness Medical Society states that:

There are no specific restrictions or mitigation strategies required for individuals who have undergone LASIK and plan to travel to high altitude.

Patients should simply be aware that environmental factors at altitude can affect all eyes—regardless of refractive surgery history—and take routine precautions such as UV protection and lubrication.

Practical Considerations for Mountaineers

For climbers and outdoor athletes, LASIK may offer practical advantages:

• Elimination of contact lens intolerance in cold, dry, windy environments

• Reduced risk of contact lens–related infection

• Improved visual reliability during technical climbing, skiing, and expeditions

Bottom Line

LASIK is safe for high-altitude mountaineering, trekking, skiing, and expedition travel once healing is complete.
There is no evidence that LASIK increases the risk of permanent vision loss at altitude. Any reported visual fluctuations are rare, temporary, and fully reversible.

For active individuals who rely on dependable vision in extreme environments, refractive surgery can be both a safe and performance-enhancing option.