Impact of 10% SF Gas Compared to 100% Air Tamponade in Descemet's Membrane Endothelial Keratoplasty.

PURPOSE

To compare the clinical outcomes following Descemet's membrane endothelial keratoplasty (DMEK) with 100% air tamponade versus 10% sulfur hexafluoride (SF) tamponade.

METHODS

Retrospective analysis of 108 consecutive DMEK cases subdivided by anterior chamber tamponade with 54 eyes receiving 10% SF and 54 eyes receiving 100% air injection. A post-hoc matched analysis revealed no statistically significant differences between the groups. The main outcome measurements were the complication rate, including intra- and postoperative complications and graft detachment rate requiring re-bubbling. Clinical outcome included best-corrected visual acuity (BCVA), endothelial cell count (ECC), and central corneal thickness (CCT) measured 1, 3, and 6 months after DMEK surgery.

RESULTS

The graft detachment rate with consecutive re-bubbling was 18.5% in the air group and 22.2% in the SF group (p = 0.2). Remaining small peripheral graft detachments with a clear cornea occurred more often in the 100% air group (air: 22.2%; 12/54, 6/12 inferior compared to SF: 7.4%; 4/54, 2/4 inferior; p = 0.06). The primary graft failure rate was comparable between the two groups. No complete graft detachment occurred. Outcome results for BCVA, ECC, and CCT at all follow-up time points were comparable between the two groups.

CONCLUSION

The clinical outcomes (including re-bubbling rate, primary graft failure rate, and endothelial cell loss) were comparable with 100% air versus 10% SF tamponade, whereas other studies suggest that a higher SF concentration (20%) may result in a lower re-bubbling rate.