# Blocking Air in the Filtering Bleb: Effects on Graft Adhesion After Descemet’s Stripping Automated Endothelial Keratoplasty

## TL;DR

This study examines how using blocking air in a filtering bleb affects graft adhesion and eye pressure after a specific type of corneal transplant surgery.

## Contribution

The study introduces a novel evaluation of blocking air's impact on graft adhesion and intraocular pressure in DSAEK patients with prior trabeculectomy.

## Key findings

- Graft detachment rates were higher when blocking air was used in the filtering bleb.
- Intraocular pressure was significantly lower in the blocking air group before and after surgery.
- Blocking air in the filtering bleb did not significantly affect graft detachment rates between subgroups.

## Abstract

Background: To evaluate the outcome of Descemet’s stripping automated endothelial keratoplasty (DSAEK) with “blocking air” in the filtering bleb in patients with previous trabeculectomy.

Methods: In total, 299 eyes in 283 patients who underwent DSAEK were retrospectively reviewed. Endothelial graft adhesion, intraocular pressure (IOP), and air volume in the anterior chamber with (group A) or without (group B) a filtering bleb were compared between the groups. Group A was divided into two subgroups according to the presence (group A1) or absence (group A2) of air in the filtering bleb; the same three factors were compared between the subgroups.

Results: The graft detachment rate was significantly higher in group A (14.3%) than in group B (6.5%) (p = 0.04). IOP was significantly lower in group A than in group B before surgery (p = 0.01), at the end of surgery (p = 0.04), at three hours (p < 0.001), and one week postoperatively (p = 0.02). The graft detachment rate did not significantly differ between groups A1 and A2. There were no differences in IOP at each follow-up time, whereas there was a statistically significant increase in IOP from the preoperative measurement to the end of surgery in group A1 (21.0±7.0 mmHg) compared with group A2 (14.2±8.6 mmHg) (p = 0.02).

Conclusions: The presence of blocking air in the filtering bleb helps ensure increased IOP during the early postoperative period but had no significant effect on graft detachment rates.