Deep anterior lamellar keratoplasties by air dissection (DALK-AD) using the big bubble (BB) technique provides good visual outcomes in keratoconus treatment, reveals a study in Cornea.

Dr David Smadja et al., National Reference Centre for Keratoconus, Bordeaux University Hospital, France, performed 44 consecutive keratoplasties on 42 keratoconus patients between January 2008 to June 2010. The team analysed the outcomes of the DALK-AD that wasn't converted to penetrating keratoplasty and a learning curve was created to achieve DALK-AD using BB.

Of the DALK-AD procedures performed, 32 were successful and 12 were converted to penetrating keratoplasty during the surgical procedure. At 12 months follow-up mean best-corrected logarithm of the minimum angle of resolution visual acuity was 0.88 ± 0.14.

Best-corrected visual acuity of ≥20/30 was seen in 93.3% of patients and 100% achieved best-corrected visual acuity of ≥20/40. At six and twelve months follow-up the mean gain of visual acuity in logarithm of the minimum angle of resolution lines was 6.12 ± 3.97 and 6.94 ± 4.18, respectively.

The DALK-AD with BB is a safe and effective technique for the surgical treatment of keratoconus. However, surgeons will need a learning period to reduce intraoperative complications.

The abstract for this investigation can be found here .