Fornix-Based Versus Limbal-Based Conjunctival Trabeculectomy Flaps for Glaucoma: Findings From a Cochrane Systematic Review

Abstract

PURPOSE To compare effectiveness of fornix- and limbal-based conjunctival flaps in trabeculectomy surgery. DESIGN Systematic review. METHODS Setting CENTRAL, MEDLINE, LILACS, ISRCTN registry, ClinicalTrials.gov, WHO, and ICTRP were searched to identify eligible randomized controlled trials (RCTs). Study Population RCTs in which benefits and complications of fornix- vs limbal-based trabeculectomy for glaucoma were compared in adult glaucoma patients. Observation Procedure We followed Cochrane methodology for data extraction. Main Outcome Measures Proportion of failed trabeculectomies at 24 months, defined as the need for repeat surgery or uncontrolled intraocular pressure (IOP) > 22 mm Hg, despite topical/systemic medications. RESULTS The review included 6 trials with a total of 361 participants, showing no difference in effectiveness between fornix-based vs limbal-based trabeculectomy surgery, although with a high level of uncertainty owing to low event rates. In the fornix-based and limbal-based surgery, mean IOP at 12 months was similar, with ranges of 12.5–15.5 mm Hg and 11.7–15.1 mm Hg, respectively. Mean difference was 0.44 mm Hg (95% CI −0.45 to 1.33) and 0.86 mm Hg (95% CI −0.52 to 2.24) at 12 and 24 months of follow-up, respectively. Mean number of postoperative glaucoma medications was similar between the 2 groups. Mean difference was 0.02 (95% CI −0.15 to 0.19) at 12 months. As far as postoperative complications, an increased risk of shallow anterior chamber was observed in the limbal-based group. CONCLUSION Similar efficacy of trabeculectomy surgery with respect to bleb failure or IOP control was observed in both types of conjunctival flap incisions. A significant difference was detected in the risk of postoperative shallow anterior chamber, which was increased in the limbal-based group.

Efficacy and Safety of Bevacizumab Combined with Mitomycin C or 5-Fluorouracil in Primary Trabeculectomy: A Meta-Analysis of Randomized Clinical Trials

“…However, the authors reported a higher risk of shallow anterior chamber in the limbal-based trabeculectomy group [30]. EI-Sayyad et al [31] also reported that efficacy, measured by IOP control and surgical success, was not significantly different.…”

Comparison of the Effect of Trabeculectomy in Controlling Intraocular Pressure in Pseudo-Exfoliaiton and Primary Open Angle Glaucoma Patients

“…As POAG and PEG groups compared in terms of intraocular pressure, cup-to-disc ratio, the number of antiglaucoma medication, there was no statistically significant difference between groups for both pre and postoperative period (p>0.05) Caprioli et al [9], reported that trabeculectomy has a visual function protecting effect resulting from reversal of the RGC functions in long-term, which is supported by electrophysiological studies. The success criteria following trabeculectomy are in a wide range in studies such as progression in visual field, loss in visual acuity or combination or both [10]. Parish et al [11], reported recovering effect of the RGC functions of the trabeculectomy in a study which is designed to compare the effect of medical and surgical treatment on the progression of the cup to disc ratio.…”

Retrospective Comparision of Trabeculectomy with Two Different Types of Conjunctival Flaps

“…This may be explained by the fact that we used MMC at a lower dose or for a shorter period of time in a small number of patients, particularly in limbus-based group and provided early intervention (steroids, needling, 5-FU) to patients who showed signs of encapsulation. Kuroda et al, compared surgical outcomes of limbal-based versus fornix-based trabeculectomy in 26 eyes with a history of ocular incisional surgery (cataract, trabeculectomy, trabeculectomy) which had conjunctival scars [38]. They couldn't find statistical difference between two methods in regard to the probability of success, the IOP value, and the number of glaucoma eye drops after trabeculectomy.…”

“…Al-Haddad et al, summarized 6 trials with a total of 361 participants comparing fornix-limbus based trabeculectomy in their review [38]. They noticed no difference in effectiveness between two trabeculectomy surgeries.…”