Preliminary investigation of a polyethylene glycol hydrogel "nerve glue"

The sciatic nerves of 29 rats were transected and repaired using two 10-0 nylon sutures and either PEG hydrogel or fibrin glue. After 10 weeks, contraction forces of the reinnervated muscles were evaluated and histological assessment of scar tissue performed.Muscle strength testing revealed the average ratio of experimental to control sides for the fibrin glue group was 0.75 and for the PEG hydrogel group was 0.72 (no significant difference). Longitudinal sections through the nerve repair site showed no significant difference in nerve diameter but did demonstrate a significant reduction in scar thickness in the PEG hydrogel group (p < 0.01).Though further study is necessary to fully evaluate, PEG hydrogel results in less scar tissue formation and equivalent muscle recovery as fibrin sealant when applied as a nerve glue in a rodent sciatic nerve repair model.The use of "surgical glues" to facilitate efficient nerve repairs is an appealing and popular concept. Autologous and commercially available fibrin sealants, such as Tisseel (Baxter Healthcare Corporation, Westlake Village, CA), are the most commonly used substances for this application. While this usage is supported by clinical and laboratory data [1-8], there are concerns regarding ultimate repair strength as well as scar generation [8-11]. Because of these concerns, we began investigating alternative "surgical glues" including polyethylene glycol (PEG) hydrogel (marketed as DuraSeal, Confluent Surgical, Inc., Waltham, MA).Like fibrin glues, DuraSeal is applied as two separate components: one is a water-soluble amine solution and the other is a multiarmed polyethylene glycol based solution. As these combine, cross-linking results in the rapid formation of a strong adherent gel like substance[12] which can be applied as a cocoon or cylinder around approximated nerve ends. Previously published biomechanical data demonstrated that the holding strength of DuraSeal when applied in this manner is equivalent to commer