Deep Anterior Lamellar Keratoplasty versus Penetrating

To compare the outcomes of deep anterior lamellar keratoplasty (DALK) using the big-bubble technique with that of penetrating keratoplasty (PK) in patients with keratoconus.

This double-blind clinical trial included patients with moderate to advanced keratoconus and poor spectacle-corrected visual acuity or contact lens intolerance. Refractive errors, best corrected visual acuity (BCVA), contrast sensitivity function (CSF) and higher order aberrations (HOAs) were compared between the study groups.

Forty-two eyes underwent DALK while 35 eyes received PK. Mean patient age was 26.91±7.9 versus 30.89±10.3 years in the DALK and PK groups, respectively (P=0.06). Mean follow-up period was 19.0±7.9 months in the DALK and 24.6±3.5 months in the PK group (P=0.32). Mean postoperative spherical equivalent refractive error was -3.23±3.4 D in the DALK group versus -2.22±4.6 D in the PK group (P=0.28) and mean postoperative BCVA was 0.18±0.08 logMAR and 0.15±0.10 logMAR, respectively (P=0.12). There was no significant difference between the study groups in terms of CSF, total aberrations and HOAs.

DALK may be considered as an effective alternative to PK in patients with keratoconus.