PURPOSE
This brief review examines both basic science and
clinical studies to evaluate the potential impact on the health of the corneal
endothelium of mitomycin C (MMC) usage during photorefractive keratectomy
(PRK).
METHODS
The mechanism of action and consequences of MMC are
reviewed within the context of in vitro, animal, and clinical studies and a
hypothesis of how this vital cell layer responds to MMC at both the cellular
and clinical levels is formed.
RESULTS
Seven basic science studies were reviewed
demonstrating significant MMC toxicity to corneal endothelial cells. Of the
five clinical studies reviewed, three demonstrated no effect on corneal
endothelial density, whereas two studies found significant cell loss after MMC
usage.
CONCLUSIONS
Although all of the basic science studies
reviewed highlight the toxicity of MMC on the corneal endothelium, current
clinical studies are less conclusive. Given the corneal penetration of MMC and
the fragile nature of the corneal endothelium, additional follow-up studies are
needed to determine the long-term impact of MMC usage during PRK on the corneal
endothelium. [J Refract Surg. 2009;25:894-897.]
doi:10.3928/1081597X-20090617-10
AUTHORS
From the Department of Ophthalmology, UPMC Eye and Ear
Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pa.
This work was supported by National Institutes of Health
grants EY016415, EY009368, and P30-EY08098; a Research to Prevent Blindness
Medical Student Fellowship; and the Eye and Ear Foundation of Pittsburgh. Dr
Funderburgh is a Jules and Doris Stein Research to Prevent Blindness Professor.
The authors have no financial or proprietary interest in the
materials presented herein.
The authors thank Deepinder K. Dhaliwal, MD, for her
valuable advice in developing this study.
Correspondence: James L. Funderburgh, PhD, 203 Lothrop St,
UPMC Eye and Ear Institute, Rm 1011, Pittsburgh, PA 15213. Tel: 412.647.3853;
Fax: 412.647.5880; E-mail: jlfunder@pitt.edu
Received: March 6, 2009; Accepted: May 5, 2009
Posted online: June 22, 2009
