PURPOSE:To determine whether corneal topical application of mitomycin-C (MMC) results in measurable plasma levels of systemic absorption. SETTING:Madigan Army Medical Center, Refractive Surgery Center, Fort Lewis, Washington, and Micro-Constants Laboratory, San Diego, California, USA. DESIGN:Case-control study. METHODS:The study comprised male and female active-duty soldiers having excimer laser photorefractive keratectomy with MMC. Patients who met inclusion criteria were asked to provide a blood sample immediately after being treated with MMC 0.2 mg/mL (0.02%) for 30 seconds. Human plasma samples were evaluated by liquid chromatography mass spectrometry to determine whether MMC was present. RESULTS:Thirty samples were submitted for evaluation. There was zero detection of MMC in the submitted samples. The quantifiable limit was greater than 10.0 ng/mL. All samples were below this. CONCLUSIONS:In this study of 30 patients with topical application of MMC for refractive surgery, there was no measurable evidence of systemic absorption. Although systemic absorption has been found with use in larger quantities, it was not known whether MMC toxicity concerns could be extrapolated to the refractive surgery population. This information allows counseling of patients on the extremely low likelihood of systemic absorption or toxicity following current techniques for refractive surgery. FINANCIAL DISCLOSURE:No author has a financial or proprietary interest in any material or method mentioned.