Revascularization of nerve grafts: an experimental study.

The time course of revascularization of grafted nerves, and the possible dependence of this revascularization on the length of the graft are two related questions that are addressed. Survival of Schwann cells in the nerve graft and a timely revascularization must be seen as a precondition for an optimal regeneration process. The revascularization process after different postoperative intervals is demonstrated in the sciatic nerve of rabbits by the use of microangiography, with Roentgen-positive water-soluble contrast medium. The third postoperative day is the earliest point in time for revascularization of the autologous graft from surrounding tissues. On the fourth postoperative day, a hyperemia with extension to all sides of the intraneural vessel system exists that still persists on the fifth and sixth days. In one experimental group, revascularization was allowed to occur only in a longitudinal direction. Revascularization under these conditions proved to be poor, slow, and obviously dependent on the length of the graft. Survival and subsequent function of free autologous nerve grafts may depend on the diameter of the grafts and the quality of the recipient site, but not on the length of the grafts, when timely revascularization from the surrounding tissues is present.