Actual behaviour of N-butyl-2-cyanoacrylate (histoacryl) in a blood vessel: a model of the varix.

BACKGROUND AND STUDY AIMS: Though many gastric varices are treated endoscopically with n-butyl-2-cyanoacrylate, its behavior in varices is not known precisely.

MATERIALS AND

METHODS

We created a varix model. A volume of 0.7 ml or 1.4 ml of 71.4 % n-butyl-2-cyanoacrylate, a tissue adhesive, was injected into vinyl tubes of 0.4, 0.6, 0.9, and 1.2 cm in diameter, which were filled with still blood or flowing blood. The tissue adhesive was also injected into the inferior vena cava or femoral vein of dogs.

RESULTS

N-butyl-2-cyanoacrylate was similarly polymerized in the vinyl tubes and the animal veins. A volume of 0.7 ml of the tissue adhesive could block all tubes up to 0.6 cm in diameter. A double quantity of the tissue adhesive could block tubes 0.9 and 1.2 cm in diameter, with flow velocities up to 10 cm/s and up to 5 cm/s, respectively. Some polymer masses were fragmented.

CONCLUSIONS

One rapid shot of the tissue adhesive can block a vessel 0.6 cm or less in diameter with fast flow velocity, and a vessel up to 1.2 cm in diameter with slow flow velocity. Fast blood flows in a larger diameter vessel and slow injection of the tissue adhesive may result in fragmentation. This model of the varix was useful for assessing the effect of tissue adhesive used to treat gastric varices.