Evaluation of the effect of preoperative corneal curvature on the successful formation of the big bubble formation in deep anterior lamellar keratoplasty for keratoconus

Background New approaches have been created to raise the chances of achieving big bubble (BB) in deep anterior lamellar keratoplasty (DALK); however, the BB formation is still uncertain in all cases. Other factors likely contribute to the success of bubble formation. Aim To evaluate the effect of preoperative curvature of the cornea on the success of BB formation in DALK for keratoconus. Design A prospective, comparative, nonrandomized study. Patients and methods The study was performed on 50 keratoconus patients. We compared the data of 25 patients who had successful type-1 bubble formation versus another 25 patients in whom the bubble formation failed. Both groups were compared regarding the keratometric readings recorded from the preoperative pentacam. Results The analysis showed statistically significant lower K1, K2, and Km values in the group where BB has been successfully achieved. We also found that lower K1 value was the only significant studied factor after the multivariate analysis. Conclusion Keratoconus patients with preoperative flatter corneas have slightly higher chances for successful BB formation during DALK surgery.