Surface ablation over LASIK flaps.

摘要

One of the challenges facing refractive surgeons is how to best approach patients who have previously undergone LASIK, and now return for additional refractive surgery. Surgeons have reported that LASIK flaps can be lifted years after surgery. However, some flaps can be extremely challenging to lift. Other patients may be poor candidates for flap-lift enhancements because of the thin residual stromal beds, as additional laser treatment to the bed could potentially lead to post-LASIK ectasia. Although there were many situations where surface ablation to enhance previous LASIK would have been a great option for patients, this procedure was not considered safe in the late 1990s. Dr Fransisco Carones looked at the possibility of performing photo-refractive keratectomy (PRK) enhancements for myopic regression after LASIK, and found very good visual results at the 1 month postoperative visit.1 However, at 3 months, 14 of 17 patients in his study experienced loss of best-corrected visual acuity because of late-onset corneal haze. After this study, the concept of PRK to enhance LASIK was considered taboo, and the message at major refractive surgery meetings was "Don't zap the flap" because of the elevated risk of late onset corneal