RESUMO
PURPOSE: To optimize the surgical technique for performing femtosecond laser-assisted keratoplasty (FLAK) using the IntraLase FS to cut both recipient and donor cornea buttons in eye bank globes. METHODS: FLAK was performed in six globes and six corneoscleral buttons for each of the following trephination patterns: top hat, mushroom, tongue-groove, and vertical. Manual trephination was performed as control. The wound integrity was tested in incisions closed with 8 sutures, 8 sutures with fibrin adhesive, and 16 sutures by measuring the intraocular pressure required to produce graft-host wound leakage (IOP(L)). Light microscopy (LM) and scanning electron microscopy (SEM) were performed to assess cut surface quality and graft-host interface regularity. RESULTS: Mushroom and top hat FLAK had significantly higher IOP(L) than vertical or manual trephination (p < 0.0001) for wounds closed with 16 sutures. There was no difference in IOP(L) between top hat, mushroom, and tongue-groove FLAK in wounds closed with 8 sutures with fibrin adhesive (p > 0.75). LM and SEM demonstrated cut surfaces with good quality and smooth edges. CONCLUSIONS: These preliminary studies show that FLAK produces precise trephination cuts of superior wound strength and stability to that of manual trephination. Adjuvant fibrin glue may further improve wound integrity.
Assuntos
Córnea/cirurgia , Ceratoplastia Penetrante/métodos , Terapia a Laser/métodos , Lasers de Excimer/uso terapêutico , Córnea/ultraestrutura , Bancos de Olhos , Adesivo Tecidual de Fibrina/uso terapêutico , Humanos , Pressão Intraocular/fisiologia , Microscopia Eletrônica de Varredura , Modelos Biológicos , Deiscência da Ferida Operatória/prevenção & controle , Técnicas de Sutura , Adesivos Teciduais/uso terapêutico , Cicatrização/fisiologiaRESUMO
PURPOSE OF REVIEW: To review current literature on overnight corneal reshaping and present this mode of vision correction in its current state. RECENT FINDINGS: Overnight corneal reshaping uses specially designed rigid gas-permeable contact lenses. It is effective in temporarily reducing or eliminating low to moderate myopia. This nonsurgical mode of vision correction allows for good unaided vision during waking hours. There are reports of young patients experiencing serious adverse events, particularly bacterial and Acanthamoeba keratitis while using these lenses, although incidence rates are unknown. SUMMARY: Overnight corneal reshaping is an alternative to refractive surgery and must continue to be studied and monitored to establish its safety.