Intraoperative sulfur hexafluoride versus air injection in eyes with formed type 2 bubble during deep anterior lamellar keratoplasty

Purpose To compare air and sulfur hexafluoride (SF6) as a tamponade agent in type 2 big bubble during deep anterior lamellar keratoplasty (DALK). Patients and methods This interventional case series study included eyes with type 2 bubble formed during DALK procedures done between May 2014 and December 2021. Cases were divided into two groups according to the tamponade agent injected at the end of the surgery. The first group was injected with air, and the second group was injected with SF6 in a nonexpansile concentration. The frequency of double anterior chamber (AC) and other postoperative data and complications were recorded. Results The study included 26 eyes, 12 in group 1 were injected with air, and 14 in group 2 were injected with SF6. Postoperative double AC was recorded in 83.3% of eyes in group 1 versus 7.1% of eyes in group 2. The χ 2 test revealed a significant association between using SF6 as tamponade at the end of the surgery and preventing a double AC postoperatively ( P <0.001). No significant differences in endothelial loss were noted between the two groups ( P =0.779). Conclusion In cases where lamellar corneal surgeons face type 2 big bubble during DALK, using SF6 at the end of the surgery may provide superior results than air in having clearer grafts and a more successful DALK surgery with much less incidence of double AC and less need for further interventions.