Phototherapeutic Keratectomy for the Treatment of Corneal Opacities After Epidemic Keratoconjunctivitis

Abstract

To assess visual results and compare methods of measuring central corneal thickness (CCT) and corneal opacity thickness (COT) in patients with corneal opacities induced by epidemic keratoconjunctivitis (EKC) and treated with phototherapeutic keratectomy (PTK) using low-dose mitomycin C (MMC). Prospective consecutive case series. Patients with chronic adenoviral corneal opacity underwent transepithelial PTK with MMC 0.002% for 1 minute. The presence of photophobia, the best spectacle-corrected visual acuity (BSCVA), and the contrast sensitivity were evaluated. CCT measurements were obtained with ultrasound pachymeter (US), ultrasound biomicroscopy (UBM), Scheimpflug tomography (Pentacam Oculus), and optical coherence tomography (OCT Visante). COT measurements were obtained with UBM, Pentacam, and OCT. Thirty-one eyes of 23 patients, comprising 15 women (65.2%) and 8 men (34.8%), mean age 41.8 years, were enrolled in the study. Duration of visual disturbance was 19.1 ± 14 months. The number of patients with photophobia was reduced from 100% to 29% after surgery. BSCVA improved 2 or more lines in 78% of the patients at 12 months. A hyperopic shift of 1.52 ± 0.91 diopters was achieved. Contrast sensitivity improved in both photopic and mesopic conditions. For each of the instruments, the CCT postoperative mean was significantly smaller than the preoperative measurement (P < .0001) and COT values were significantly reduced in comparison to the preoperative values (P < .001). Improvements in photophobia, BSCVA, and contrast sensitivity were observed in patients treated using excimer laser PTK with low-dose MMC for subepithelial infiltrates.