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The visual outcome and complications in deep anterior lamellar keratoplasty for keratoconus

Objective The aim of this study was to evaluate visual outcomes and complications of deep anterior lamellar keratoplasty (DALK) using the big-bubble technique in patients with keratoconus. Background Keratoconus is a bilateral noninflammatory corneal thinning disorder leading to protrusion, distortion, and scarring of the cornea. Treatment options are glasses, hard contact lenses, cross-linking, intracorneal segment insertion, refractive surgery, or keratoplasty. DALK can be a better choice to manage cases of moderate and some cases of severe keratoconus without deep scarring and severe thinning. Participants and methods This interventional study was carried out on 47 eyes of 46 patients who presented with moderate to advanced keratoconus for DALK from December 2012 to June 2014 with a mean follow-up of 12 months. The best spectacle-corrected visual acuity, the refractive status, and intraoperative and postoperative complications were evaluated. Results Thirty-seven procedures (78.7%) were completed with big-bubble formation, and six patients (12.8%) required manual intrastromal dissection. Intraoperative microperforations occurred in four cases (8.5%). The mean preoperative uncorrected visual acuity was 0.036 ± 0.017 and the final best spectacle-corrected visual acuity at 1 year had a mean value of 0.38 (P < 0.001). The postoperative mean spherical equivalent refractive error and astigmatism were − 4.9 ± 2.6 and − 3.9 ± 1.6 D, respectively. Main complications encountered included loosening of the stitches in 11 cases (23.4%), vascularization of the stitches in three cases (6.4%), double anterior chamber in two cases (4.3%), Urrets-Zavalia syndrome in one case (2.1%), stromal rejection in one case (2.1%), and suture abscess in one case (2.1%). Conclusion DALK using the big-bubble technique appears to be a safe and effective procedure in patients with keratoconus. Postoperative myopic astigmatism is observed in most of the cases.