The importance of the apposition of the submucosal intestinal layers for primary wound healing of intestinal anastomosis.

This study was undertaken to examine the importance of the apposition of the submucosal layers in healing of the intestinal anastomosis. On 18 mongrel dogs, weighing between 8 and 15 kilograms, four anastomoses were performed on the small intestine. Two with a conventional anastomosis and two with rings of polyester-polyethyleneterephtalate, containing small Ticonal magnets. The force between the rings with the magnets varied from 0-3 newton between, respectively, 15 millimeters and zero millimeter distance. After three to four days, the rings cut through and disappeared from the anastomosis. Morphologic and microangiographic studies, undertaken at ten days, revealed that, in instances of good submucosal apposition, direct bridging of the defect in the submucosal layer was seen with rapid restoration of the villous epithelium and an undisturbed vascular pattern in the anastomotic area. This we called primary intestinal healing. In instances of bad submucosal apposition, we saw indirect bridging of the submucosal layer defect by smaller and longer strands of newly synthesized collagen tissue in the outer intestinal layers with a collateral circulation from the submucosal plexus to the arterial plexuses in these layers. In all instances, an epithelial defect still persisted at ten days. This type of wound healing we called secondary intestinal healing. The results showed that, with the magnetic rings, a significantly better apposition of the intestinal layers was achieved.