Photorefractive keratectomy with mitomycin C after deep anterior lamellar keratoplasty for keratoconus.
OBJECTIVE
To evaluate the safety and efficacy of photorefractive keratectomy (PRK) with intraoperative mitomycin C (MMC) after deep anterior lamellar keratoplasty (DALK) for keratoconus.


METHODS
This was a prospective, noncomparative single-surgeon study. Eyes with compound myopic astigmatism after DALK with a spherical equivalent (SE) between -3 and -10 D were treated by PRK. After ablation, MMC 0.2 mg/mL was placed on the stromal bed for 45 seconds. A 6% undercorrection was planned.


RESULTS
The study was completed on 10 eyes of 10 patients. The preoperative mean SE was -4.98 +/- 1.75 (SD) D. At 10 months after surgery, the mean SE was 0.28 +/- 0.61 D, and the mean defocus equivalent was 1.08 +/- 0.58 D. Postoperatively, 9 eyes were within 2 D, 6 were within 1 D, and 1 eye was within 0.5 D of defocus equivalent. The preoperative mean best spectacle-corrected visual acuity (BSCVA) was 0.68 +/- 0.15 D, and at 10 months it was 0.78 +/- 0.13 D. The 95% confidence interval for the mean difference of pre- and postoperative BSCVA was 0.02-0.17 (P < 0.05). No lines of BSCVA were lost. The mean postoperative uncorrected visual acuity was 0.55 +/- 0.1. The safety index was 1.15, and the efficacy index was 0.81. Corneal haze was grade 0 in 8 eyes and grade 0.5 in 2 eyes. Mean epithelialization time was 4.1 +/- 0.99 days. Preoperative mean endothelial cell density was 2320 +/- 184 cells/mm(2), and at 10 months it was 2284 +/- 175 cells/mm(2).


CONCLUSIONS
PRK with MMC can safely and effectively correct myopia and regular myopic astigmatism after DALK. Undercorrection should be planned to compensate for the overcorrecting effect of MMC.
Leccisotti
Antonio
A
Ophthalmic Surgery Unit, Casa di Cura Rugani, Siena, Italy. leccisotti@libero.it
D000328:Adult; D000477:Alkylating Agents / Q000008:administration & dosage*; D001251:Astigmatism / Q000188:drug therapy / Q000601:surgery / Q000628:therapy*; D002452:Cell Count; D003131:Combined Modality Therapy; D019781:Corneal Topography; D016039:Corneal Transplantation; D004728:Endothelium, Corneal / Q000473:pathology; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000601:surgery*; D054018:Lasers, Excimer; D008297:Male; D016685:Mitomycin / Q000008:administration & dosage*; D009216:Myopia / Q000188:drug therapy / Q000601:surgery / Q000628:therapy*; D018903:Photorefractive Keratectomy / Q000379:methods*; D011446:Prospective Studies; D014792:Visual Acuity
D000477:Alkylating Agents; D016685:Mitomycin