Deep anterior lamellar keratoplasty using the big-bubble technique for keratectasia after laser in situ keratomileusis
PURPOSE: To evaluate the efficacy of deep anterior lamellar keratoplasty (DALK) using the big-bubble technique to manage keratectasia after laser in situ keratomileusis (LASIK). SETTING: Ophthalmology Department and Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. METHODS: In this interventional case series, preoperative and postoperative data of patients who had post-LASIK ectasia and DALK using the Anwar big-bubble technique between April 2005 and May 2008 were compiled. Indications for keratoplasty were intolerance of rigid gas-permeable contact lenses or unacceptable corrected visual acuity. Preoperative and postoperative uncorrected (UDVA) and corrected (CDVA) distance visual acuities, spherical equivalent (SE) refractive error, mean keratometry, and keratometric astigmatism were compared. RESULTS: The study included 11 eyes of 10 patients (mean age 31.6 years +/- 7.4 [SD]). The mean follow-up was 20.2 +/- 6.5 months. The mean UDVA increased from 20/400 before DALK to 20/160 after DALK (P = .39) and the CDVA, from 20/160 to 20/40, respectively (P = .007). The increase in the mean SE refractive error was 1.94 diopters (D) (from -11.53 +/- 5.4 D to -13.47 +/- 10.5 D) (P = .34). The mean keratometry was 46.81 +/- 7.2 D preoperatively and 46.31 +/- 1.9 D postoperatively (P = .81) and the mean keratometric astigmatism, 4.75 +/- 2.6 D and 4.55 +/- 2.5 D, respectively (P = .81), showing little change in either parameter. CONCLUSION: Deep anterior lamellar keratoplasty using the big-bubble technique effectively restored corneal regularity and thus increased CDVA; however, a high refractive error should be expected postoperatively.