A Comparison of Various Vascularization-Perfusion Venous Nerve Grafts with Conventional Nerve Grafts in Rats

ABSTRACT

Peripheral nerves with defective segments can only be repaired using nerve grafts. Among the various nerve graft options, the outcome of vascularized grafts has been shown to be better, especially when used in the hypovascular and scarred recipient bed. The purpose of this study was to compare the regeneration capacities of various types of venous nerve grafts in a rat model. Forty adult male Wistar albino rats were divided into four groups. A 2-cm-long segment of femoral sheath was isolated from the surrounding tissue without disturbing the unity of the femoral sheath contents. Four different nerve graft models were applied: flow-through venous, arterialized venous, prefabricated venous, and conventional nerve graft (control). All nerve grafts were closed with silicone sheets. These neurovascular segments were reopened in postoperative week 10 to determine the viability of the grafted nerves and to assess the degree of nerve healing. Histopathologic examinations, morphometric analysis, and electrophysiological measurements were performed. The degree of nerve healing in the flow-through venous nerve grafts was similar to that observed in the arterialized nerve grafts. Prefabricated flow-through venous grafts were not as successful as flow-through venous grafts or arterialized nerve grafts. All of the vascularized nerve grafts showed better results than the conventional nerve grafts.

KEYWORDS

Venous nerve graft - peripheral nerve healing - vascularized nerve graft model

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