Comparison of conjunctival pedicle flap to corneal fixation strength achieved by Tisseel® fibrin glue, ethyl cyanoacrylate adhesive, ReSure® hydrogel sealant, and conventional suturing with 8-0 VICRYL® ophthalmic suture

Abstract

Objective To determine and compare the fixation strength of conjunctival pedicle flaps to cornea achieved via conventional ophthalmic suture and three different adhesive compounds. Animals Studied Ex vivo porcine globes. Procedures Following a 6 mm wide 500-micron-restricted depth lamellar keratectomy, conjunctival pedicle flaps were secured to the keratectomy site with either 8-0 VICRYL (R) suture or one of three adhesive products, including Tisseel (R) bioadhesive, ReSure (R) synthetic adhesive, or ethyl cyanoacrylate adhesive (n = 10 per surgical group). Adhesive application protocol varied by product based upon adhesive biocompatibility. Corneoconjunctival tissues were then harvested, clamped in a tensile testing device, and loaded at a rate of 1 mm/s under video surveillance until the point of failure. Peak load was determined for each test and used to compare fixation strength between samples. Results Forty conjunctival flaps were performed, with 6 omitted from evaluation due to dehiscence prior to tensile testing. Of the 34 flaps analyzed, 10 were secured with suture, 10 with cyanoacrylate, 8 with ReSure (R), and 6 with Tisseel (R). Flaps secured with suture withstood significantly higher applied tensile force compared with cyanoacrylate (p = .02474), ReSure (R) (p = .00000), and Tisseel (R) (p = .00002). Flaps secured with cyanoacrylate withstood significantly greater force than those secured with ReSure (R) and Tisseel (R) (p = .01194 and 0.01798, respectively). There was no significant difference in fixation strength between ReSure (R) and Tisseel (R) glue (p = .95675). Conclusions Conjunctival pedicle flap fixation using 8-0 VICRYL (R) suture fixation was able to withstand significantly greater maximum tensile force compared to ReSure (R), Tisseel (R), or cyanoacrylate adhesives. Fixation strength achieved with cyanoacrylate adhesive was significantly greater than that achieved with ReSure (R) or Tisseel (R).