Deep anterior lamellar keratoplasty techniques; predescemetic versus big bubble: Anterior segment optical coherence tomography study

To compare the visual and refractive outcomes and anterior segment optical coherence tomography (AS-OCT) findings of 2 different deep anterior lamellar keratoplasty (DALK) techniques in the treatment of advanced keratoconus with and without successful big bubble formation. In this retrospective comparative case series, data from 79 consecutive eyes of 69 patients who underwent either big bubble (group 1, n: 62) or manual DALK (group 2, n: 17) were analyzed. The visual and refractive results, keratometric values and residual stromal thickness were assessed. Patients were seen at 1, 3, 6 and 12 months after the procedure and 1 month after complete suture removal. A big bubble was successfully obtained in 62 eyes (78.5%; group 1) and manual dissection was performed in the 17 remaining eyes (21.5%; group 2). The final best spectacle-corrected visual acuity (BSCVA) was 0.38 logMAR and 0.55 logMAR in Group 1 and 2, respectively (P