Abstract

Background/aims: To evaluate the microscopic epithelial features seen with In Vivo Confocal Microscopy (IVCM) of bulbar conjunctiva in glaucomatous patients undergoing trabeculectomy with mitomycin C in order to elucidate modifications.

Methods: Fifteen eyes of 15 consecutive Caucasian patients affected with primary open angle glaucoma (POAG) undergoing trabeculectomy and 10 eyes of 10 glaucomatous patients (controls) under medical therapy were enrolled. Eyes were examined using digital confocal Laser-Scanning Microscope (HRT II Rostock Cornea Module) at baseline and after 6 weeks. Mean microcyst density (MMD: cysts/mm2) and microcyst area (MMA: µm2) were the main outcome measurements.

Results: Before surgery, mean intra-ocular pressure (IOP) was 25.1±3.2 mmHg. MMD and MMA were 22.4±11.9 and 4696.0±3608.1, respectively. After trabeculectomy, mean IOP was 16.1±1.7mmHg. A marked increase in both MMD and MMA, with values of 103.1±22.6 and 29489.3±12954.9, were respectively observed. In the control group at baseline, the mean IOP was 15.7±1.9mmHg and the microcysts parameters did not differ from eyes undergoing filtering surgery. After six weeks, IOP and microcysts parameters did not show significant modifications.

Conclusion: Conjunctival modifications were pre-existing to trabeculectomy since epithelial microcysts were demonstrable in glaucomatous eyes under medical therapy. The filtering procedure increased microcysts density and surface at the bleb site, indicating a marked post-surgical enhancement of aqueous filtration across conjunctiva.