Morphologic analysis of the fibular nerve repaired with fibrin adhesive.

THE development of ultrafine surgical sutures with low tissue reactivity, more efficient optical equipment, and specialized microsurgical instrumentation has produced important advances in morphologic and functional recovery of peripheral nerves. Studies have shown that appropriate axonal apposition, minimal manipulation, and sustentation of nervous tissue can contribute to nerve regeneration. Surgical techniques constitute an important factor in the efficacy of peripheral nerve regeneration. The use of appropriate nerve anastomotic techniques (end-to-end or end-toside suture), preservation of the myelin layer that involves the neurons, application of synthetic or biologic materials to nerve stumps, and administration of growth agents to stimulate axons have been evaluated intensively for their role in promoting regeneration of peripheral nerves. Reduced tissue manipulation, attenuated inflammatory responses to sutures and neural repair without tension represent the basic conditions for successful morphologic and functional anastomosis of peripheral nerves. Several biologic adhesives, including fibrin adhesive, have been alternatively proposed for peripheral nerve anastomosis. Studies have shown that fibrin adhesive exerts hemostatic action and causes macrophage activation, producing several factors involved in angiogenesis, fibroblast and endothelium cell proliferation, and collagen synthesis. In contrast to fibrin, cyanoacrylate adhesives have shown low efficacy for peripheral nerve regeneration due to tissue lesions produced by the polymerization and exothermic reaction. However, the effects of fibrin adhesives on regeneration of anastomosed peripheral nerves are unknown. Using histologic methods, we compared axonal regeneration in rat fibular nerves submitted to end-to-side anastomosis using fibrin adhesive versus polyamide 9.0 suture.