LAUSR

Post‐LASIK epithelial ingrowth (PLEI)‐ is uncommon but visually threatening complication of LASIK, with incidence ranging from 0%–3.9% in primary treatment cases to 10%– 20% in retreatment cases.[1] However, clinically significant PLEI requiring removal was noted in only 0.92%–3.2%.[1] Epithelial ingrowth occurs due to the implantation of basal epithelial cells under the flap, which is mechanically dragged during keratectomy by the microkeratome blade. It has also been stated that poor adherence of flap to the underlying stroma can cause epithelial cell migration.[2] Risk factors include trauma, intraocular surgeries, excessive instrumentation and interface manipulation, hyperopia, and increased patient age. Based on the location, clinical features, and severity, PLEI can be categorized into four grades using the Probst/Machat classification.[3] This classification serves as a useful aid for consistent and standardized grading/assessment and provides guidance on the treatment strategies. Early diagnosis and proper management are necessary to prevent visually threatening complications. The most common treatment is flap lifting and scraping of epithelium from the stromal bed and underside of the flap. However, a high recurrence rate of 44% was observed with this technique.[4] Thus, many adjunct techniques were used to prevent recurrence, such as the use of alcohol, mitomycin C, fibrin glue, phototherapeutic keratectomy, flap suturing, and amniotic membrane graft. In more severe cases, flap amputation and transepithelial topography‐guided ablation have been described. In less severe cases, Nd:YAG lasers have been used in an attempt to bypass a surgical approach. Lifting the flap has the disadvantage of nonuniform trauma to the flap edge, which can be sufficient to introduce epithelial cells beneath the flap or increase edema at the edge, coinciding with a higher incidence of epithelial ingrowth after enhancement compared to after initial LASIK. The disruption of ingrown epithelium via Nd:YAG laser using low energy (0.6 mJ on average) offers a safe and effective alternative to other treatments for epithelial ingrowth after LASIK treatment and enhancement.[5]