Wound healing in the cornea: a review of refractive surgery complications and new prospects for therapy.
OBJECTIVE
The corneal wound healing response is of particular relevance for refractive surgical procedures since it is a major determinant of efficacy and safety. The purpose of this review is to provide an overview of the healing response in refractive surgery procedures.


METHODS
Literature review.


RESULTS
LASIK and PRK are the most common refractive procedures; however, alternative techniques, including LASEK, PRK with mitomycin C, and Epi-LASIK, have been developed in an attempt to overcome common complications. Clinical outcomes and a number of common complications are directly related to the healing process and the unpredictable nature of the associated corneal cellular response. These complications include overcorrection, undercorrection, regression, corneal stroma opacification, and many other side effects that have their roots in the biologic response to surgery. The corneal epithelium, stroma, nerves, inflammatory cells, and lacrimal glands are the main tissues and organs involved in the wound healing response to corneal surgical procedures. Complex cellular interactions mediated by cytokines and growth factors occur among the cells of the cornea, resulting in a highly variable biologic response. Among the best characterized processes are keratocyte apoptosis, keratocyte necrosis, keratocyte proliferation, migration of inflammatory cells, and myofibroblast generation. These cellular interactions are involved in extracellular matrix reorganization, stromal remodeling, wound contraction, and several other responses to surgical injury.


CONCLUSIONS
A better understanding of the complete cascade of events involved in the corneal wound healing process and anomalies that lead to complications is critical to improve the efficacy and safety of refractive surgical procedures. Recent advances in understanding the biologic and molecular processes that contribute to the healing response bring hope that safe and effective pharmacologic modulators of the corneal wound healing response may soon be developed.
Netto
Marcelo V
MV
The Cole Eye Institute, The Cleveland Clinic Foundation, OH 44195, USA.
Mohan
Rajiv R
RR
Ambrósio
Renato
R
Hutcheon
Audrey E K
AE
Zieske
James D
JD
Wilson
Steven E
SE
D000818:Animals; D017209:Apoptosis; D003315:Cornea / Q000502:physiology*; D065306:Corneal Injuries; D006801:Humans; D007431:Intraoperative Complications; D020731:Keratomileusis, Laser In Situ; D054018:Lasers, Excimer; D018903:Photorefractive Keratectomy; D011183:Postoperative Complications; D012030:Refractive Errors / Q000503:physiopathology; D054140:Refractive Surgical Procedures; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology*