Clinical Results of Deep Anterior Lamellar Keratoplasty in Treatment of Advanced Keratoconus; Big Bubble Technique
Purpose: To evaluate refractive results and complications of deep anterior lamellar keratoplasty (DALK) using Anwar's big bubble technique in advanced keratoconus.
Study Design: Quasi experimental study
Place and Duration of Study: Armed Forces Institute of Ophthalmology, Rawalpindi from November 2015 to December 216.
Material and Methods: Seventeen eyes of seventeen patients with advanced keratoconus who underwent DALK using Anwar's big bubble technique with1 year postoperative follow up were included in study. Uncorrected and Corrected Distant Visual Acuities (UDVA, CDVA, Snellen acuity converted to logMAR notation), Spherical Equivalent SE (Diopters D)], refractive Astigmatism [(Ast, D)], Slit lamp biomicroscopy and endothelial Cell Count (ECD) were recorded at baseline and at 1, 6 and 12 months postoperatively. Intra and postoperative complications were documented.
Results: The mean patient age was 26.29 ± 10.403 years including 12 males (76.47%) and 4 (23.53%) females. The mean baseline logMAR UDVA and CDVA were1.376 ± 0.286 and 1.211 ± 0.228, which significantly improved at all test points to final logMAR UDVA and CDVA of 0.964 ± 0.183 and 0.647 ± 0.279 at 1 year (p = 0.000, 0.000 respectively). Improvement in Ast was only significant at 1 year (p=.0.0) while changes in SE were not significant (p = .0.330). No significant ECD loss (p) or rejection was recorded at any postoperative exam.
Conclusion: DALK using Anwar’s big bubble technique has shown lesser complications in terms of endothelial rejection and endothelial cell loss with satisfactory refractive results in young keratoconus patients and we recommend it to be a preferred surgical technique over penetrating keratoplasty, despite its technical challenges and steep surgical learning curve.
Key words: DALK, Anwar's big bubble, refractive outcome, advanced keratoconus, Pakistani population