[Forms of an in vivo polymerization product, n-butyl-2-cyanoacrylate, within the gastric wall].

The in vivo morphology of sclerosants, n-butyl-2-cyanoacrylate (Histoacryl; referred hereinafter to briefly as HA) polymer formed within the gastric wall was investigated in an animal experiment. The results indicate that HA polymer formed after local injection of HA into the stomach wall with deliberate avoidance of contact with blood got scattered in an arboroid pattern, suggesting thus that when HA is injected into the gastric mucosa at an extravascular site, the resulting polymer is likely to get scattered and miss the target site. Polymerization products that were formed after injection of HA alone were deep purple, dense, firm, rounded in shape and lesser in adverse histologic influence upon the walls of stomach. On the other hand, those formed by injection of HA with Lipiodol were large-sized, light brown and oval-shaped ones with more irregular margins and less distinct boundaries as compared to those seen after injection of HA alone. These results of the study led us to conclude that at the present time it would seem wise to limit the use of HA for this particular therapeutic purpose only to those cases of bleeding gastric varices.