Which procedure is considered less likely to cause permanent vision change?

LASEK (Laser-Assisted Sub-Epithelial Keratectomy) is considered less likely to cause permanent vision change primarily due to its unique procedural approach. LASEK involves using a diluted alcohol solution to loosen the epithelial layer of the cornea, which is then gently pushed aside. After the laser reshapes the corneal tissue beneath, the epithelial layer is repositioned, allowing it to heal naturally without complete removal. This preservation of the epithelial cells helps maintain the cornea’s structural integrity, leading to a potentially lower risk of long-term complications and permanent changes in vision when compared to other techniques.

In contrast, surgeries like LASIK, PRK, and SMILE involve more significant alterations to the corneal structure. LASIK and SMILE reshape the cornea with the removal of more substantial amounts of corneal tissue, while PRK removes the epithelium entirely before reshaping the underlying stroma. These processes can increase the risk of complications that might lead to permanent vision changes, such as corneal haze or irregularities in corneal healing.