Subconjunctival sodium hyaluronate 2.3% in trabeculectomy: a prospective randomized clinical trial

Abstract

Purpose: To investigate the efficacy of subconjunctival sodium hyaluronate 2.3% in increasing the success rate of glaucoma filtering surgery and promoting filtering blebs with characteristics presumed to predict better success.

Design: Randomized controlled clinical trial.

Participants: Fifty-five patients scheduled for glaucoma surgery.

Intervention: Patients underwent routine trabeculectomy, with or without phacoemulsification and intraocular lens implantation. In the study group (n = 28), sodium hyaluronate 2.3% was injected between the scleral and conjunctival flaps at the conclusion of the surgery. In the control group (n = 27), balanced salt solution (BSS) was injected in the same fashion, in an unmasked design.

Main outcomes measures: Surgical success was defined as (1) a complete success if the intraocular pressure (IOP) was 21 mmHg or less without any antiglaucoma medication, and (2) a qualified success if the IOP was 21 mmHg or less, with or without antiglaucoma medication. Patients requiring additional surgery, including needling, or with IOP more than 21 mmHg, even when receiving antiglaucoma medications, were considered to have failed treatment. Success rates in both groups were compared using Kaplan-Meier survival curves and the log-rank test. The morphologic characteristics of the filtering blebs were evaluated using the Indiana Bleb Appearance Grading Scale. Other outcome measures were IOP, visual acuity, need for antiglaucoma medication, and any complications.

Results: Fifty-two patients completed the study (27 in the study group and 25 in the control group), with a mean follow-up of 12.3 months. Complete success rates were 77.8% for the study group and 84.0% for the control group 12 months after surgery (P>0.5); qualified success rates were 88.9% for the study group and 92.0% for the control group (P>0.6). Mean IOP decreased from 26.0+/-10.0 mmHg to 11.6+/-4.1 mmHg in the study eyes (P<0.001) and from 24.9+/-9.7 mmHg to 13.0+/-4.1 mmHg in the control eyes (P<0.001). Intraocular pressure measurements in both groups were similar at all visits (P>0.05). The study eyes had more diffuse blebs than the control eyes (62.5% > or =4 clock-hours vs. 22.7%; P = 0.012). Postoperative complications were similar in the study eyes (14.8%) and the control eyes (20.0%; P>0.6).

Conclusions: There was no difference in success rates in patients who received subconjunctival sodium hyaluronate 2.3% compared to BSS injections. Subconjunctival sodium hyaluronate 2.3% was associated with more diffuse blebs after filtering surgery.